How the Amish Keep Food Cold Without Electricity | Boring History

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Hey there, you tired little 
sigmas. 

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I know my content helps you 
sleep quickly, so let's snuggle 

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up and let me tell you a story 
here tonight. 

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Where preservation doesn't 
require a power chord, where the

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rhythm of seasons dictates the 
contents of your pantry, and 

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where a block of ice represents 
not just cold but community. 

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We're stepping into the lives of
the Amish, whose methods for 

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keeping food fresh stretch back 
centuries, blending ingenuity 

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with tradition in ways that 
might surprise you. 

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So settle in, get comfortable, 
and let's explore how an entire 

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culture stays fed without ever 
flipping a switch. 

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So if you are new to the channel
or returning, liking the video 

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and commenting significantly 
helps us out. 

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Also, please let me know where 
you are listening in from and 

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what time it is for you. 
Now get comfortable and let's 

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begin. 
You wake before dawn in an Amish

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farmhouse, and the first thing 
you notice is what you don't 

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hear. 
There's no mechanical hum 

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vibrating through the 
floorboards, no compressor 

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cycling on in the corner of the 
kitchen, and no ambient 

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electrical buzz that modern life
has trained your ears to ignore.

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Instead, you hear the actual 
sounds of morning, a rooster 

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clearing his throat in the barn,
the settling creak of wood beams

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cooling from yesterday's warmth,
and your own breathing. 

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In the darkness. 
You pad barefoot across wide 

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plank floors that still hold a 
whisper of coolness from the 

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night. 
The kitchen reveals itself 

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gradually as your eyes adjust, 
taking shape not from overhead 

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fluorescence but from the pale 
blue suggestion of dawn pressing

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against the windows. 
Everything here works on 

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principles that predate Edison's
laboratories. 

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The stove runs on propane. 
It's pilot like a tiny 

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constellation in the darkness. 
The lamps use compressed gas 

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that hisses softly when you turn
the valve, and somewhere deep in

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the earth beneath your feet sits
a chamber carved from clay and 

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stone, where tonight's dinner 
waits in perpetual twilight. 

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Your hand finds the cool metal 
handle of what looks like a 

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compact refrigerator, but when 
you open it, the light that 

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appears isn't electric but 
chemical, a simple glow produced

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by the refrigeration process 
itself. 

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This is a gas powered 
refrigerator, a technology that 

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sounds impossible until you 
remember that cold is simply the

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absence of heat, and heat can be
manipulated in more ways than 

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one. 
The unit uses ammonia, hydrogen,

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and water in a continuous cycle,
creating cold through 

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evaporation and condensation 
rather than the electrical 

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compression. 
It's quieter than it's electric 

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cousin, just an occasional 
gurgle as liquids change states,

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doing their molecular dance. 
Inside you find glass jars of 

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milk, their cream rising in 
thick plugs at the top because 

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nobody here homogenizes 
anything. 

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There's a ceramic crock of 
butter, firm enough to hold its 

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shape but soft enough to spread 
easily on fresh bread. 

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A covered dish holds last 
night's chicken, the fat 

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congealed into savoury Jelly 
around the meat. 

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Everything sits arranged with 
the precision of someone who 

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understands that cold air sinks 
and warm air rises, that proper 

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placement matters when your 
cooling system runs on 

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absorption rather than forced 
convection. 

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But this gas refrigerator is 
actually the newest technology 

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in this kitchen, installed 
perhaps 20 years ago after 

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considerable debate within the 
community. 

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The real story of Amish food 
preservation lies deeper, 

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colder, and considerably older. 
It's written in the architecture

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of the land itself, in holes dug
into hillsides and stones 

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stacked with purpose. 
To understand how the Artemis 

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keep food cold without 
electricity, you need to 

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understand that they're not 
rejecting modern convenience so 

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much as embracing ancient wisdom
that never needed improvement in

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the 1st place. 
You grab a sweater from a peg by

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the door, because even in 
summer, where you're about to go

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remains locked in permanent 
October. 

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The path outside leads around 
the side of the house, past herb

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garden, still wet with dew, to a
door set almost flush with a 

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gentle slope in the yard. 
This isn't the entrance to a 

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storm shelter or a coal bin. 
This is where winter lives year 

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round, where the earth itself 
becomes a refrigerator, and 

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where gravity and geology 
conspire to keep things fresh. 

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This is the root cellar, and 
it's about to teach you things 

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about temperature that no 
appliance manual ever could. 

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The door opens with a wooden 
groan, exhaling cool air that 

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smells like minerals and 
darkness, like the inside of a 

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cave where bears sleep through 
blizzards. 

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You descend steps carved from 
packed earth, your hand trailing

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along a Stonewall that feels 
damp but not wet, cool but not 

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cold, alive in ways that 
concrete never manages. 

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Each step down brings a 
perceptible temperature drop, as

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if you're descending through 
layers of atmosphere, moving 

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from one microclimate to 
another. 

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At the bottom, perhaps 12 feet 
below the surface, you find 

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yourself in a room that 
shouldn't exist according to 

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everything modern life taught 
you about food storage. 

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There's no insulation in the 
contemporary sense, no vapour 

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barriers or thermal breaks. 
The walls are simply stacked 

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stone, fitted together with the 
patience of someone who 

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understood the air gaps matter, 
that every space between rocks 

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serves as a buffer zone. 
The floor is packed, Earth 

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slightly damp, completing a 
circuit with the walls and 

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ceiling that maintains A 
remarkably consistent 

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temperature, somewhere between 
45 and 55°F. 

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This consistency exists because 
you're now below the frost line,

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in the zone where seasonal 
temperature swings barely 

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register. 
While the world above bakes or 

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freezes, this chamber remains 
locked in perpetual autumn. 

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The earth's own mass acts as a 
thermal battery, absorbing heat 

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in summer and releasing it in 
winter, creating a stable 

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environment that your ancestors 
understood intuitively. 

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They might not have known the 
thermodynamics, but they knew 

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that potatoes stored here in 
October would still be firm in 

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March, that apples would keep 
their crunch until spring mud 

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season, and that the earth was 
the original refrigerator and 

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required no maintenance plan. 
The shells reveal themselves as 

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your eyes adjust to the dim 
light filtering down the 

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stairway. 
Wooden boards rest on stone 

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supports, each shelf 
strategically positioned 

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according to principles of 
temperature stratification. 

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The lowest shelves, where the 
coldest air pools, hold root 

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vegetables that tolerate near 
freezing conditions. 

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Carrots packed in sand, beets 
nestled in sawdust and turnips 

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wrapped in newspaper. 
These storage methods aren't 

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quaint affectations, but 
practical solutions to moisture 

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management. 
The sand and sawdust prevent the

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vegetables from touching each 
other while maintaining ideal 

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humidity, stopping both 
desiccation and rot. 

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Middle shelves hold glass jars 
of preserved goods. 

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Pickles floating in cloudy 
brine, Applesauce the colour of 

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sunset and green beans packed 
with dill heads that look like 

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tiny fireworks frozen mid 
explosion, These jars represent 

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summer captured and held 
hostage, prevented from spoiling

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by carefully calibrated acidity 
and the absence of air. 

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Canning is its own form of cold 
storage when you think about it,

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creating an environment so 
hostile to bacteria that food 

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remains suspended in time, 
waiting patiently to be 

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remembered and consumed months 
after its harvest. 

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The highest shelves, where 
temperatures climb closer to 

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60°, hold items that prefer less
aggressive cooling. 

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Winter squash with their thick 
skins that protect sweet orange 

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flesh, onions braided together 
like rope, and garlic bulbs that

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fill the air with their pungent 
promise. 

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Up here, near the ceiling, the 
air moves slightly, stirred by 

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convection currents that flow 
down the stairs, across the 

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floor, and back up again in an 
endless loop. 

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This circulation isn't designed 
so much as allowed, the natural 

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consequence of opening a cool 
chamber to warmer air above. 

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But what makes this root cellar 
remarkable isn't just its 

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function, but also its 
redundancy and its passive 

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nature. 
Nothing needs to be plugged in 

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or turned on. 
No compressor will fail at 

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midnight during a heat wave. 
No power outage will leave you 

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mourning your lost groceries. 
The root cellar simply exists, 

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doing what it's done for 
centuries, asking nothing but 

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occasional attention and respect
for its principles. 

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It's the ultimate set it and 
forget it appliance, installed 

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by previous generations and 
maintained by the simple act of 

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closing the door when you're 
finished retrieving your 

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turnips. 
The root seller solves the 

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problem of modest cooling, but 
what about actual freezing? 

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What happens when you need ice, 
rather than just coolness and 

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preservation requires 
temperatures that make frost 

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feathers across surfaces. 
For that, you need to travel 

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backward in time to winter 
itself, or more specifically, to

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the moment when winter was 
something you could harvest and 

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store, when frozen water became 
currency and a planning tool. 

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Walk with me now to the Ice 
House, that peculiar structure 

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that sits 100 yards from the 
main house. 

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Built into the north side of a 
hill where sunshine fears to 

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tread even in summer, this 
building looks like an oversized

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shed from the outside, but it's 
construction reveals obsessive 

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attention to insulation. 
Double walls create a six inch 

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gap filled with sawdust that's 
been packed tight as insulation.

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The roof sports 2 layers with an
air gap between them, and the 

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door fits into its frame like a 
watchmaker's masterpiece, with 

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wool weather stripping that 
keeps warm air out more 

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effectively than any modern 
refrigerator seal. 

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Inside, even in July, the 
temperature hovers just above 

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freezing. 
The air carries A mineralized 

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coldness that makes your breath 
visible, that tightens the skin 

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on your arms and raises every 
hair in salute. 

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Stacked from floor to ceiling, 
separated by layers of straw, 

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sit blocks of ice harvested 5 
months ago when the pond was a 

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solid sheet and the world was 
frozen solid. 

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These blocks, each roughly 2 
feet square and 18 inches thick,

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represent a winter's day of 
communal labour, of men and 

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horses and sores working in 
concert to capture cold for 

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future use. 
The ice harvest was a January 

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ritual timed precisely for that 
window, after the pond had 

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frozen at least 12 inches thick 
but before snow accumulated 

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heavily enough to insulate the 
ice and slow its thickening. 

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You would have seen the entire 
community gather on a Saturday 

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morning when breath frosted 
beards and children stamped 

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their feet against cold that 
penetrated boot leather. 

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Someone would have scored the 
ice with a horse drawn plow 

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fitted with metal teeth, 
creating a grid of lines that 

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marked where blocks should be 
cut. 

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Then the soaring would begin, 
men working in pairs with long 2

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handled saws that sang through 
ice with a distinctive grinding 

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shriek. 
Each block, once freed from its 

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brothers, would be guided 
towards shore using Pike poles, 

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then hoisted onto a wooden slide
where it would be loaded onto a 

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wagon and transported to the ice
house. 

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The loading required 
choreography worthy of a ballet 

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company. 
Too much haste and blocks would 

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crack. 
Too much delay and they'd begin 

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freezing together. 
Too little sawdust between 

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layers and they'd fuse into one 
massive, unusable block. 

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Over the months the work 
generated a peculiar warmth 

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despite sub freezing 
temperatures, the kind of heat 

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that comes from exertion rather 
than environment. 

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So men would shed coats and work
in shirtsleeves while their 

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breath created private weather 
systems around their heads. 

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The physics of ice house storage
are brutally simple but 

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deceptively effective. 
Ice wants to melt, but melting 

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requires heat energy. 
The sawdust insulation slows 

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heat transfer to a crawl, and 
the blocks themselves create 

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their own cooling zone that 
resists warming as outer layers 

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slowly melt over months. 
They refreeze slightly each 

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night, creating a self sealing 
barrier. 

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Meltwater drains away through 
the floor into a carefully 

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engineered runoff system, 
preventing the remaining ice 

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from sitting in water that would
accelerate melting. 

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By late summer, you might have 
lost 40% of your harvest to 

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melting, but 60% of a January 
crop still means frozen storage 

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capacity through September. 
This ice serves multiple 

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purposes beyond just chilling 
food. 

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Cream destined to become ice 
cream gets packed in wooden 

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buckets surrounded by ice and 
rock salt, the salt lowering the

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freezing point and creating 
temperatures below 32°. 

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Meat can be kept for days rather
than hours when buried in ice, 

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and butter stays firm even when 
the thermometer pushes 90° 

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outside. 
The ice house essentially 

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00:13:15,000 --> 00:13:18,720
extends winter on demand, 
letting you summon cold whenever

232
00:13:18,720 --> 00:13:22,280
necessary, proof that you can 
indeed save the weather for 

233
00:13:22,280 --> 00:13:25,080
later if you plan ahead. 
But perhaps the most elegant 

234
00:13:25,080 --> 00:13:28,200
solution to food preservation 
sits where water emerges from 

235
00:13:28,200 --> 00:13:31,000
the earth itself. 
In structures built around 

236
00:13:31,000 --> 00:13:34,360
springs that flow year round 
with water that never varies 

237
00:13:34,360 --> 00:13:38,520
more than a few degrees from 
it's constant 54° temperature, 

238
00:13:39,360 --> 00:13:42,040
the spring house combines 
running water with careful 

239
00:13:42,040 --> 00:13:45,120
architecture to create a cooling
system that operates 

240
00:13:45,120 --> 00:13:48,760
continuously without any input 
beyond gravity and geology. 

241
00:13:49,120 --> 00:13:53,600
Picture a small stone building, 
maybe 10 feet by 12, built 

242
00:13:53,600 --> 00:13:58,120
directly over a natural spring, 
the water emerges from the 

243
00:13:58,120 --> 00:14:00,560
ground. 
Inside, the structure flows 

244
00:14:00,560 --> 00:14:04,320
through a shallow channel carved
from stone and exits through an 

245
00:14:04,320 --> 00:14:08,440
opening in the wall downhill. 
The building's walls are thick 

246
00:14:08,440 --> 00:14:12,240
stone, 2 feet or more, and the 
roof is heavily insulated with 

247
00:14:12,240 --> 00:14:15,800
sod or slate. 
Small windows near the roof line

248
00:14:15,800 --> 00:14:18,440
allow air circulation but 
prevent direct sunlight from 

249
00:14:18,440 --> 00:14:21,560
entering. 
The door faces north and is 

250
00:14:21,560 --> 00:14:24,960
typically double layered with an
air gap between, creating an 

251
00:14:24,960 --> 00:14:27,640
airlock that maintains the cool 
interior temperature. 

252
00:14:27,960 --> 00:14:30,920
Inside, the spring channel 
dominates the floor plan. 

253
00:14:31,560 --> 00:14:33,920
This isn't a stream you'd step 
across casually. 

254
00:14:34,240 --> 00:14:38,320
It's maybe 2 feet wide and eight
inches deep, flowing with gentle

255
00:14:38,320 --> 00:14:41,560
insistence. 
The water stays crystal clear 

256
00:14:41,560 --> 00:14:44,680
because spring water emerges 
filtered through layers of sand 

257
00:14:44,680 --> 00:14:48,240
and rock, stripped of sediment 
and organic material. 

258
00:14:48,920 --> 00:14:52,760
More importantly, it stays cold,
drawing its temperature from the

259
00:14:52,760 --> 00:14:57,520
aquifer 50 or 100 feet below, 
where seasonal variations never 

260
00:14:57,520 --> 00:15:00,200
penetrate. 
Along both sides of the channel 

261
00:15:00,200 --> 00:15:03,200
sit stone platforms where Crocs 
and jars are placed. 

262
00:15:03,920 --> 00:15:07,160
Milk Crocs, still warm from the 
morning milking, are set 

263
00:15:07,160 --> 00:15:10,160
directly into the water, which 
immediately begins stealing 

264
00:15:10,160 --> 00:15:12,920
their heat. 
The flowing water carries that 

265
00:15:12,920 --> 00:15:16,240
heat away downstream, preventing
any temperature build up that 

266
00:15:16,240 --> 00:15:20,040
would occur in Stillwater. 
Within an hour, milk that left 

267
00:15:20,040 --> 00:15:25,200
the cow at 98° has dropped to 
60°, extending its freshness 

268
00:15:25,200 --> 00:15:28,680
from hours to days. 
By evening, it's down to the 

269
00:15:28,680 --> 00:15:32,320
springs, ambient temperature 
cold enough that cream rises 

270
00:15:32,320 --> 00:15:35,280
slowly and bacteria reproduction
slows to a crawl. 

271
00:15:35,640 --> 00:15:38,960
Butter Crocs sit on the slightly
higher platforms, not in the 

272
00:15:38,960 --> 00:15:41,720
water but close enough that 
evaporative cooling from the 

273
00:15:41,720 --> 00:15:45,800
stream creates a microclimate 
10° cooler than the surrounding 

274
00:15:45,800 --> 00:15:49,040
air. 
Eggs rest in wire baskets that 

275
00:15:49,040 --> 00:15:52,760
hang in the water. 
Flow kept cool but not cold, 

276
00:15:53,240 --> 00:15:56,320
preserved in that sweet spot 
where there last weeks instead 

277
00:15:56,320 --> 00:15:59,000
of days. 
Covered dishes containing 

278
00:15:59,000 --> 00:16:02,560
leftovers line the shelves above
the water, benefiting from the 

279
00:16:02,560 --> 00:16:04,440
general coolness without getting
damp. 

280
00:16:04,880 --> 00:16:07,360
The spring house operates on 
principles that modern 

281
00:16:07,360 --> 00:16:10,360
refrigeration engineers would 
recognise but execute with 

282
00:16:10,360 --> 00:16:15,000
mechanical complexity. 
Cool air, being denser than warm

283
00:16:15,000 --> 00:16:18,160
air, flows downward and pulls in
the lower spaces. 

284
00:16:18,800 --> 00:16:22,640
The spring water continuously 
generates cool air as it flows, 

285
00:16:22,960 --> 00:16:26,240
and that air stays low, trapped 
by the building's design. 

286
00:16:27,080 --> 00:16:30,480
Warm air enters through the high
windows and exits the same way, 

287
00:16:30,880 --> 00:16:33,960
prevented from descending by the
cold air cushion below. 

288
00:16:34,720 --> 00:16:37,960
This creates stratification, 
with the coldest zone right at 

289
00:16:37,960 --> 00:16:41,680
water level where the milk Crocs
sit, slightly warmer zones at 

290
00:16:41,680 --> 00:16:44,800
shelf height, and the warmest 
air near the ceiling, where 

291
00:16:44,800 --> 00:16:47,920
nothing perishable is stored. 
What makes the Spring House 

292
00:16:47,920 --> 00:16:51,320
remarkable is its responsiveness
to external conditions. 

293
00:16:52,080 --> 00:16:55,720
On hot summer days, when you 
need cooling, most people visit 

294
00:16:55,720 --> 00:16:58,520
the Spring house more 
frequently, opening the door and

295
00:16:58,520 --> 00:17:00,640
disturbing the temperature 
stratification. 

296
00:17:01,120 --> 00:17:05,520
But each opening also introduces
warm air that the spring water 

297
00:17:05,520 --> 00:17:09,160
immediately begins cooling, and 
the increased air circulation 

298
00:17:09,160 --> 00:17:11,480
actually improves the system's 
efficiency. 

299
00:17:12,079 --> 00:17:15,800
In winter, when cooling is less 
critical, the Spring House sees 

300
00:17:15,800 --> 00:17:19,040
less traffic and the building's 
thermal mass prevents the 

301
00:17:19,040 --> 00:17:22,160
interior from freezing. 
Even when January drives 

302
00:17:22,160 --> 00:17:26,119
temperatures below 0 outside, 
the water that flows out of the 

303
00:17:26,119 --> 00:17:29,440
spring house doesn't go to waste
downstream. 

304
00:17:29,680 --> 00:17:32,360
It might water livestock or 
irrigate a garden. 

305
00:17:32,800 --> 00:17:35,680
It's work is never done, despite
having already served as 

306
00:17:35,680 --> 00:17:39,320
refrigerant. 
This multiple use philosophy 

307
00:17:39,320 --> 00:17:41,360
pervades Amish food 
preservation. 

308
00:17:41,760 --> 00:17:44,360
Nothing exists for a single 
purpose when it conserves 

309
00:17:44,360 --> 00:17:47,200
several. 
An energy, whether human, 

310
00:17:47,400 --> 00:17:50,880
animal, or natural, is always 
asked to pull double duty 

311
00:17:50,880 --> 00:17:53,880
whenever possible. 
Back in the kitchen, the gas 

312
00:17:53,880 --> 00:17:56,920
refrigerator deserves a closer 
look because it represents A 

313
00:17:56,920 --> 00:18:00,080
fascinating compromise between 
modern convenience and 

314
00:18:00,080 --> 00:18:04,480
traditional principles approved 
by most Amish communities. 

315
00:18:04,480 --> 00:18:07,720
Because it doesn't connect to 
the electrical grid, the gas 

316
00:18:07,720 --> 00:18:10,360
refrigerator operates on 
principles that would seem like 

317
00:18:10,360 --> 00:18:12,720
magic if they weren't just 
clever chemistry. 

318
00:18:13,040 --> 00:18:16,320
The absorption refrigeration 
cycle sounds complicated but 

319
00:18:16,320 --> 00:18:20,640
follows a beautiful logic. 
Inside the sealed system, 

320
00:18:20,920 --> 00:18:24,000
ammonia dissolves in water to 
create a solution that gets 

321
00:18:24,000 --> 00:18:28,200
heated by a small gas flame no 
bigger than what you'd see on a 

322
00:18:28,200 --> 00:18:31,720
water heater pilot light. 
This heating separates the 

323
00:18:31,720 --> 00:18:35,360
ammonia from the water, and the 
gaseous ammonia rises to a 

324
00:18:35,360 --> 00:18:38,720
condenser at the top of the 
unit, where it cools back into 

325
00:18:38,720 --> 00:18:41,280
liquid, releasing heat in the 
process. 

326
00:18:42,120 --> 00:18:45,600
That liquid ammonia then flows 
to an evaporator coil inside the

327
00:18:45,600 --> 00:18:49,480
refrigerator compartment, where 
it meets hydrogen gas in a low 

328
00:18:49,480 --> 00:18:51,640
pressure environment. 
Here's where it gets 

329
00:18:51,640 --> 00:18:54,480
interesting. 
The hydrogen doesn't participate

330
00:18:54,480 --> 00:18:57,640
in cooling directly, but lowers 
the partial pressure of the 

331
00:18:57,640 --> 00:19:00,520
ammonia, which allows the 
ammonia to evaporate at low 

332
00:19:00,520 --> 00:19:03,680
temperatures. 
This evaporation absorbs heat 

333
00:19:03,680 --> 00:19:07,360
from inside the refrigerator, 
which is just a fancy way of 

334
00:19:07,360 --> 00:19:11,520
saying it creates cold. 
The ammonia gas then flows to an

335
00:19:11,520 --> 00:19:14,960
absorber where it meets water 
again, dissolves back into 

336
00:19:14,960 --> 00:19:18,400
solution, and the cycle 
continues indefinitely as long 

337
00:19:18,400 --> 00:19:20,320
as that tiny flame keeps 
burning. 

338
00:19:20,720 --> 00:19:24,280
The beauty of this system is its
lack of moving parts, no 

339
00:19:24,280 --> 00:19:27,680
compressor cycling on and off, 
no fan motors pushing air 

340
00:19:27,680 --> 00:19:31,000
around, and no electronic 
controls deciding when to 

341
00:19:31,000 --> 00:19:33,840
defrost. 
The refrigerator runs 

342
00:19:33,840 --> 00:19:37,720
continuously at its own pace, 
creating cold through heat in a 

343
00:19:37,720 --> 00:19:40,160
paradox that nonetheless works 
perfectly well. 

344
00:19:41,200 --> 00:19:43,920
The only maintenance it requires
is occasional cleaning of the 

345
00:19:43,920 --> 00:19:47,280
burner and a yearly check to 
ensure the flue isn't blocked. 

346
00:19:47,960 --> 00:19:51,840
Otherwise, it simply operates 
year after year, consuming a 

347
00:19:51,840 --> 00:19:55,200
gallon of propane every week or 
two, depending on ambient 

348
00:19:55,200 --> 00:19:58,000
temperature and how often the 
door opens. 

349
00:19:58,320 --> 00:20:00,480
The interior looks familiar to 
anyone who's opened a 

350
00:20:00,480 --> 00:20:04,520
refrigerator, shelves and door 
storage, a small freezer 

351
00:20:04,520 --> 00:20:07,520
compartment and crisper drawers 
for vegetables. 

352
00:20:08,240 --> 00:20:11,440
But the cooling isn't uniform 
like an electric model. 

353
00:20:12,040 --> 00:20:15,400
The freezer sits at the top, 
where the evaporator coil runs 

354
00:20:15,400 --> 00:20:18,040
coldest. 
And temperature increases 

355
00:20:18,040 --> 00:20:21,680
gradually toward the bottom. 
This means you need to store 

356
00:20:21,680 --> 00:20:24,720
things strategically. 
Milk on the top shelf where it 

357
00:20:24,720 --> 00:20:28,560
stays coldest, vegetables in the
bottom drawers where they won't 

358
00:20:28,560 --> 00:20:31,840
freeze, and leftovers in the 
middle zones according to their 

359
00:20:31,840 --> 00:20:35,280
sensitivity to temperature. 
This temperature gradient isn't 

360
00:20:35,280 --> 00:20:37,600
a flaw, but a feature if you 
understand it. 

361
00:20:38,440 --> 00:20:40,800
Different foods have different 
optimal storage. 

362
00:20:40,800 --> 00:20:43,480
Temperatures in a single 
temperature environment is 

363
00:20:43,520 --> 00:20:46,400
actually a compromise that suits
nothing perfectly. 

364
00:20:47,160 --> 00:20:51,840
Eggs keep best around 45°, just 
barely cool enough to slow 

365
00:20:51,840 --> 00:20:54,960
bacteria, but not so cold that 
flavours mute. 

366
00:20:55,640 --> 00:21:00,240
Milk wants 38°, cold enough to 
suppress spoilage but not so 

367
00:21:00,240 --> 00:21:04,960
cold it freezes. 
Leafy greens prefer 32° with 

368
00:21:04,960 --> 00:21:08,400
high humidity, while root 
vegetables like it slightly 

369
00:21:08,400 --> 00:21:11,840
warmer and drier. 
The gas refrigerator's natural 

370
00:21:11,840 --> 00:21:15,280
temperature stratification lets 
you find the right zone for each

371
00:21:15,280 --> 00:21:17,600
food. 
If you understand the map, most 

372
00:21:17,600 --> 00:21:20,400
Amish families who use gas 
refrigerators treat them as 

373
00:21:20,400 --> 00:21:23,480
supplements to their traditional
storage methods rather than 

374
00:21:23,480 --> 00:21:26,760
replacements. 
The refrigerator handles daily 

375
00:21:26,760 --> 00:21:29,960
use items and foods that don't 
store well in root Cellars or 

376
00:21:29,960 --> 00:21:35,360
spring houses, fresh milk, 
butter, eggs, leftovers and 

377
00:21:35,360 --> 00:21:37,320
produce that's been cut or 
prepared. 

378
00:21:38,080 --> 00:21:42,200
Meanwhile, the bulk storage of 
preserved goods, root vegetables

379
00:21:42,200 --> 00:21:46,280
and seasonal harvests still 
happens in those older, passive 

380
00:21:46,280 --> 00:21:49,400
systems that don't require fuel 
or maintenance. 

381
00:21:49,920 --> 00:21:52,760
This layered approach to food 
storage demonstrates a principle

382
00:21:52,760 --> 00:21:56,040
worth noting. 
Sometimes the best technology is

383
00:21:56,040 --> 00:21:59,480
several technologies working 
together, each handling what it 

384
00:21:59,480 --> 00:22:02,120
does best. 
On an August afternoon, when the

385
00:22:02,120 --> 00:22:05,880
garden reaches its productive 
zenith, the kitchen transforms 

386
00:22:05,880 --> 00:22:08,960
into something between a 
laboratory and a factory, a 

387
00:22:08,960 --> 00:22:13,320
space dedicated to the ancient 
art of making food immortal 

388
00:22:13,320 --> 00:22:16,600
through heat, acid and sealed 
glass. 

389
00:22:17,280 --> 00:22:21,360
Canning day has arrived, that 
marathon session where bushels 

390
00:22:21,360 --> 00:22:25,320
of tomatoes or beans or Peaches 
get processed into shelf stable 

391
00:22:25,320 --> 00:22:28,760
jars that will feed the family. 
When snow covers the garden, the

392
00:22:28,760 --> 00:22:32,360
process begins with washing. 
So much washing that your hands 

393
00:22:32,360 --> 00:22:36,600
prune and the sink overflows 
with discarded stems and leaves.

394
00:22:37,120 --> 00:22:41,680
Tomatoes pile in bowls, their 
skins taut and glossy, still 

395
00:22:41,680 --> 00:22:44,040
warm from the garden where they 
were picked at dawn. 

396
00:22:45,000 --> 00:22:48,760
The variety matters here. 
Paste tomatoes with their thick 

397
00:22:48,760 --> 00:22:52,920
walls and minimal seeds, bred 
specifically for canning because

398
00:22:52,920 --> 00:22:56,200
they break down into the perfect
consistency for sauce. 

399
00:22:56,960 --> 00:23:00,400
Slicing tomatoes with their 
juicy interiors wouldn't work as

400
00:23:00,400 --> 00:23:03,760
well, creating too much liquid 
and not enough body. 

401
00:23:04,120 --> 00:23:07,680
The stove holds multiple pots in
various stages of the process. 

402
00:23:08,200 --> 00:23:12,520
One large pot sterilises jars in
boiling water, keeping them hot 

403
00:23:12,520 --> 00:23:15,160
until the moment they're filled 
so the glass won't crack from 

404
00:23:15,160 --> 00:23:18,600
thermal shock. 
Another pot contains the actual 

405
00:23:18,600 --> 00:23:22,240
food being canned tomatoes 
cooking down with a bit of salt 

406
00:23:22,240 --> 00:23:25,920
and maybe a leaf of basil, their
skin slipping off in the heat to

407
00:23:25,920 --> 00:23:30,400
be scooped away and added to the
compost bucket. 1/3 pot holds 

408
00:23:30,400 --> 00:23:33,720
the jar lids in hot water, 
softening the rubber sealing 

409
00:23:33,720 --> 00:23:36,320
compound that will create an 
airtight bond when everything 

410
00:23:36,320 --> 00:23:38,680
cools. 
The filling requires steady 

411
00:23:38,680 --> 00:23:42,560
hands and attention to detail. 
Each jar gets packed full, 

412
00:23:42,840 --> 00:23:45,200
leaving only 1/4 inch of 
headspace at the top. 

413
00:23:45,720 --> 00:23:48,600
Too much space and bacteria 
might survive in the air pocket,

414
00:23:49,000 --> 00:23:52,640
Too little and the jar might not
seal properly as its contents 

415
00:23:52,640 --> 00:23:56,920
expand during processing. 
A clean towel wipes each rim 

416
00:23:56,920 --> 00:24:00,240
because even a tiny smear of 
food can prevent a proper seal. 

417
00:24:01,000 --> 00:24:05,240
The lids go on firmly but not 
obsessively tight, just enough 

418
00:24:05,240 --> 00:24:07,880
to hold them in place while 
allowing air to escape during 

419
00:24:07,880 --> 00:24:10,240
processing. 
Then comes the water bath. 

420
00:24:10,400 --> 00:24:13,720
Assuming these are high acid 
foods like tomatoes or Pickles, 

421
00:24:14,280 --> 00:24:17,040
the jars go into a huge pot with
a rack on the bottom. 

422
00:24:17,040 --> 00:24:18,800
To prevent direct contact with 
heat. 

423
00:24:19,600 --> 00:24:22,800
Water must cover the jars by at 
least an inch, and then the 

424
00:24:22,800 --> 00:24:26,400
whole assembly gets brought to a
boil and maintained there for 

425
00:24:26,400 --> 00:24:28,160
however long the recipe 
specifies. 

426
00:24:28,600 --> 00:24:32,760
Maybe 25 minutes for quart jars 
of tomatoes, 45 minutes for 

427
00:24:32,760 --> 00:24:37,000
larger jars, or longer if you're
at an altitude where water boils

428
00:24:37,000 --> 00:24:39,840
at lower temperatures. 
During processing, pressure 

429
00:24:39,840 --> 00:24:43,160
inside the jars builds as 
contents heat and expand, 

430
00:24:43,480 --> 00:24:47,120
forcing air out past the lids. 
When you remove the jars and 

431
00:24:47,120 --> 00:24:49,920
they begin cooling, that 
pressure drops as contents 

432
00:24:49,920 --> 00:24:53,480
contract, but now the lids are 
seated tightly against the rim. 

433
00:24:53,760 --> 00:24:56,840
The resulting vacuum sucks the 
lid down with enough force that 

434
00:24:56,840 --> 00:25:00,400
you hear it's seal, a 
distinctive ping or pop that 

435
00:25:00,400 --> 00:25:04,280
signals success. 
A sealed jar can sit on a shell 

436
00:25:04,280 --> 00:25:08,120
for a year or more, its contents
protected from air and bacteria 

437
00:25:08,120 --> 00:25:10,520
by nothing more than heat 
treatment and the absence of 

438
00:25:10,520 --> 00:25:13,320
oxygen. 
Low acid foods like green beans 

439
00:25:13,320 --> 00:25:16,200
or corn require more aggressive 
processing because they can 

440
00:25:16,200 --> 00:25:19,520
harbour Botulism spores that 
survive boiling temperatures. 

441
00:25:20,560 --> 00:25:23,840
For these you need a pressure 
canner, A specialized pot that 

442
00:25:23,840 --> 00:25:28,080
can raise internal temperatures 
to 240° by trapping steam and 

443
00:25:28,080 --> 00:25:30,960
building pressure. 
The pressure canner sits on the 

444
00:25:30,960 --> 00:25:34,720
stove like a small bomb, it's 
gauge requiring constant 

445
00:25:34,720 --> 00:25:37,440
monitoring to maintain precisely
the right pressure. 

446
00:25:37,960 --> 00:25:41,560
Too little and the food won't 
reach sterilization temperature,

447
00:25:42,080 --> 00:25:45,720
Too much and you risk either a 
failed seal or, in extreme 

448
00:25:45,720 --> 00:25:49,040
cases, an explosion of glass and
vegetables across your kitchen. 

449
00:25:49,440 --> 00:25:52,520
The canning pantry fills 
gradually over summer and fall, 

450
00:25:52,920 --> 00:25:56,640
jars accumulating like library 
books until shelves grown under 

451
00:25:56,640 --> 00:25:58,960
the weight. 
There's a satisfaction in 

452
00:25:58,960 --> 00:26:02,000
looking at those preserved 
goods, knowing that February's 

453
00:26:02,000 --> 00:26:05,200
dinner is already prepared and 
waiting, that the garden's 

454
00:26:05,200 --> 00:26:07,960
bounty wasn't lost to the 
compost heat but captured at 

455
00:26:07,960 --> 00:26:11,840
peak ripeness. 
Each jar represents not just 

456
00:26:11,840 --> 00:26:16,600
food but time and labour, a 
choice to prepare for seasons 

457
00:26:16,600 --> 00:26:20,480
ahead, to value self-sufficiency
over convenience. 

458
00:26:20,800 --> 00:26:25,040
Canning predates refrigeration 
by centuries and remains viable 

459
00:26:25,040 --> 00:26:27,920
precisely because it doesn't 
depend on continuous energy 

460
00:26:27,920 --> 00:26:31,720
input. 
Once processed and sealed, jars 

461
00:26:31,720 --> 00:26:35,200
need nothing but a cool, dark 
storage space. 

462
00:26:35,720 --> 00:26:39,720
No electricity means no power 
bills and no risk of spoilage 

463
00:26:39,720 --> 00:26:43,520
from mechanical failure. 
The only enemy is time itself, 

464
00:26:43,800 --> 00:26:47,200
which gradually degrades quality
even in sealed jars. 

465
00:26:47,720 --> 00:26:51,400
But properly canned goods remain
safe for years, even if their 

466
00:26:51,400 --> 00:26:54,040
peak flavour might fade after 
the first year. 

467
00:26:54,360 --> 00:26:57,600
The architecture of an Amish 
home reveals cooling strategies 

468
00:26:57,600 --> 00:27:01,400
built into the structure itself,
passive designs that work with 

469
00:27:01,400 --> 00:27:05,920
climate rather than against it. 
These aren't afterthoughts, but 

470
00:27:05,920 --> 00:27:08,920
fundamental principles that 
shape how the building meets the

471
00:27:08,920 --> 00:27:12,000
world, creating comfortable 
interior temperatures through 

472
00:27:12,000 --> 00:27:15,440
positioning materials and 
airflow management. 

473
00:27:15,760 --> 00:27:19,920
Start with orientation. 
The long axis of the house runs 

474
00:27:19,920 --> 00:27:23,920
east West, presenting A narrow 
face to the summer sun's path. 

475
00:27:24,600 --> 00:27:28,280
This minimises solar gain during
the hottest part of the day when

476
00:27:28,280 --> 00:27:30,720
the sun tracks high across the 
southern sky. 

477
00:27:31,720 --> 00:27:35,760
Large windows face North and 
South rather than east and West,

478
00:27:36,240 --> 00:27:39,240
allowing light without the harsh
direct sun that would heat 

479
00:27:39,240 --> 00:27:42,880
interior spaces. 
The South facing windows get 

480
00:27:42,880 --> 00:27:47,440
shaded by deep overhangs, 
calibrated to let in winter sun 

481
00:27:47,680 --> 00:27:51,800
when it tracks low, but blocks 
summer sun when it climbs high. 

482
00:27:52,480 --> 00:27:56,400
This passive solar design costs 
nothing to operate and never 

483
00:27:56,400 --> 00:27:58,520
requires maintenance beyond 
cleaning windows. 

484
00:27:58,520 --> 00:28:01,200
Occasionally. 
The walls themselves are thick, 

485
00:28:01,360 --> 00:28:05,040
often 18 inches or more. 
Combining traditional framing 

486
00:28:05,040 --> 00:28:09,200
with substantial insulation, 
this thermal mass slows heat 

487
00:28:09,200 --> 00:28:13,400
transfer in both directions, 
keeping cool interior air from 

488
00:28:13,400 --> 00:28:16,720
escaping on hot days and 
preventing outside heat from 

489
00:28:16,720 --> 00:28:20,240
penetrating easily. 
The materials matter, too. 

490
00:28:20,720 --> 00:28:24,240
Plaster over lath creates a 
denser, more massive interior 

491
00:28:24,240 --> 00:28:27,920
surface than modern drywall, and
that mass stores coolness from 

492
00:28:27,920 --> 00:28:30,960
night air and releases it 
gradually through the day. 

493
00:28:32,160 --> 00:28:35,800
You can feel this effect if you 
visit at mid afternoon, when 

494
00:28:35,800 --> 00:28:40,600
outside temperatures push 90° 
but interior walls remain cool 

495
00:28:40,600 --> 00:28:43,680
to the touch, still holding onto
the memory of dawn. 

496
00:28:43,960 --> 00:28:47,680
Windows open in strategic pairs 
to create cross ventilation that

497
00:28:47,680 --> 00:28:51,040
pulls air through the house. 
A window near the floor on the 

498
00:28:51,040 --> 00:28:54,680
north side emits cool air that 
sinks naturally, while a window 

499
00:28:54,680 --> 00:28:57,280
near the ceiling on the South 
side exhaust warm air that 

500
00:28:57,280 --> 00:28:59,920
rises. 
This isn't random chance but 

501
00:28:59,920 --> 00:29:03,280
deliberate design, creating a 
convective current that 

502
00:29:03,280 --> 00:29:07,800
continuously refreshes interior 
air without fans or blowers. 

503
00:29:08,880 --> 00:29:11,840
On summer nights, every window 
in the house might open, 

504
00:29:12,280 --> 00:29:15,280
allowing cool evening air to 
flush out the day's accumulated 

505
00:29:15,280 --> 00:29:18,960
heat. 
By morning, the house interior 

506
00:29:18,960 --> 00:29:23,320
sits 10 or 15° cooler than it 
will be by evening, and closing 

507
00:29:23,320 --> 00:29:27,280
windows before the day heats up 
traps that coolness inside The 

508
00:29:27,280 --> 00:29:29,880
basement provides additional 
cooling through it's contact 

509
00:29:29,880 --> 00:29:31,800
with stable subsurface 
temperatures. 

510
00:29:32,440 --> 00:29:35,320
In traditional design, the 
kitchen often included a summer 

511
00:29:35,320 --> 00:29:38,480
kitchen in the basement, where 
cooking could happen without 

512
00:29:38,480 --> 00:29:42,360
heating the main living spaces. 
Bread could be baked, meals 

513
00:29:42,360 --> 00:29:46,000
prepared, and preserves 
processed in a space that never 

514
00:29:46,000 --> 00:29:50,480
exceeded 70°, even when the 
thermometer outside climbed past

515
00:29:50,480 --> 00:29:53,880
90. 
This vertical separation of 

516
00:29:53,880 --> 00:29:57,160
function based on temperature is
brilliant in its simplicity. 

517
00:29:57,600 --> 00:30:01,040
Hot activities happen when 
natural coolness exists and 

518
00:30:01,040 --> 00:30:04,640
living spaces stay comfortable. 
Porches wrap around multiple 

519
00:30:04,640 --> 00:30:08,000
sides of the house, creating 
shaded buffer zones that prevent

520
00:30:08,000 --> 00:30:10,480
direct sun from hitting walls 
and windows. 

521
00:30:11,200 --> 00:30:14,240
These porches serve as outdoor 
rooms where much of summer life 

522
00:30:14,240 --> 00:30:17,680
happens, providing comfortable 
spaces without requiring the 

523
00:30:17,680 --> 00:30:19,520
main house to accommodate 
gatherings. 

524
00:30:19,520 --> 00:30:23,840
During heat, the porch roof, 
typically 6 to 8 feet deep, 

525
00:30:24,160 --> 00:30:28,440
casts shadows that move with the
sun, keeping walls cool during 

526
00:30:28,440 --> 00:30:32,120
the hottest hours. 
Come evening, families gather on

527
00:30:32,120 --> 00:30:35,360
these porches to catch breezes 
and escape residual heat from 

528
00:30:35,360 --> 00:30:39,240
cooking, talking until darkness 
brings mosquitoes and sends 

529
00:30:39,240 --> 00:30:42,440
everyone inside to beds 
positioned near open windows. 

530
00:30:42,800 --> 00:30:46,160
The attic plays a crucial role 
in the thermal system, despite 

531
00:30:46,160 --> 00:30:47,960
being the hottest space in the 
house. 

532
00:30:48,760 --> 00:30:51,760
Good attic ventilation, 
typically Gable vents at each 

533
00:30:51,760 --> 00:30:55,880
end combined with soffit vents 
under the eaves, allows hot air 

534
00:30:55,880 --> 00:30:59,560
to escape rather than radiating 
down through ceilings into 

535
00:30:59,560 --> 00:31:02,840
living spaces. 
Some homes include whole house 

536
00:31:02,840 --> 00:31:06,400
fans in the ceiling of the top 
floor hallway, human powered 

537
00:31:06,400 --> 00:31:10,040
fans with pulleys that can be 
operated to exhaust attic heat 

538
00:31:10,480 --> 00:31:12,600
and pull cool air up from the 
basement. 

539
00:31:13,480 --> 00:31:17,080
This creates a chimney effect, 
moving air through the entire 

540
00:31:17,080 --> 00:31:21,360
house in a cleansing circulation
that requires no electricity, 

541
00:31:21,760 --> 00:31:24,120
just someone willing to pull a 
rope for a few minutes. 

542
00:31:24,520 --> 00:31:27,560
Paint colours contribute too, 
though the Amish typically avoid

543
00:31:27,560 --> 00:31:30,280
bright colours for cultural 
reasons rather than thermal 

544
00:31:30,280 --> 00:31:32,880
management. 
White or light coloured 

545
00:31:32,880 --> 00:31:36,120
exteriors reflect solar 
radiation instead of absorbing 

546
00:31:36,120 --> 00:31:39,640
it, keeping surface temperatures
lower than dark colours would. 

547
00:31:40,320 --> 00:31:44,160
Metal roofs common on Amish 
buildings reflect considerable 

548
00:31:44,160 --> 00:31:48,400
heat and shed it quickly once 
the sun drops, unlike asphalt 

549
00:31:48,400 --> 00:31:51,600
shingles that store heat and 
radiate it for hours after 

550
00:31:51,600 --> 00:31:54,040
sunset. 
Understanding Amish food 

551
00:31:54,040 --> 00:31:57,160
preservation means recognizing 
that their entire approach 

552
00:31:57,160 --> 00:31:59,800
follows seasonal rhythms rather 
than fighting them. 

553
00:32:00,520 --> 00:32:02,800
The calendar dictates what's 
available and what needs 

554
00:32:02,800 --> 00:32:06,520
preserving, creating a yearly 
cycle where each season's work 

555
00:32:06,520 --> 00:32:09,920
prepares for the next. 
Spring arrives with a paradox. 

556
00:32:10,240 --> 00:32:13,200
The root cellar is getting low 
just as fresh food becomes 

557
00:32:13,200 --> 00:32:16,440
available again. 
Those potatoes planted last 

558
00:32:16,440 --> 00:32:19,840
April and stored in October, are
sprouting eyes by March, and 

559
00:32:19,840 --> 00:32:22,240
though they're still edible, 
they're past their prime. 

560
00:32:22,600 --> 00:32:27,640
But spring brings early greens, 
lettuce, spinach and radishes 

561
00:32:28,080 --> 00:32:30,680
that need no preservation 
because they'll be eaten within 

562
00:32:30,680 --> 00:32:34,320
days of harvest. 
Spring also means baby animals, 

563
00:32:34,760 --> 00:32:37,720
which means fresh milk is 
suddenly abundant after winter's

564
00:32:37,720 --> 00:32:40,960
reduced production. 
This milk becomes butter and 

565
00:32:40,960 --> 00:32:45,040
cheese, preserved dairy products
that extend freshness from days 

566
00:32:45,040 --> 00:32:47,600
to months. 
Summer is preservation's busy 

567
00:32:47,600 --> 00:32:51,520
season, a marathon of activity 
when the garden explodes with 

568
00:32:51,520 --> 00:32:54,600
productivity. 
June brings strawberries that 

569
00:32:54,600 --> 00:32:58,680
must be jammed or frozen quickly
because they spoil within days. 

570
00:32:59,200 --> 00:33:03,200
July means cucumbers turning 
into Pickles, a transformation 

571
00:33:03,200 --> 00:33:05,520
that happens in Crocs on the 
kitchen counter. 

572
00:33:05,920 --> 00:33:09,880
A salt and time convert fresh 
vegetables into tangy preserved 

573
00:33:09,880 --> 00:33:13,040
ones. 
August is tomato season, 

574
00:33:13,440 --> 00:33:16,600
requiring all day canning 
sessions that leave you smelling

575
00:33:16,600 --> 00:33:19,680
like a pizza kitchen but 
yielding dozens of jars that 

576
00:33:19,680 --> 00:33:21,600
will make winter pasta sauce 
possible. 

577
00:33:22,600 --> 00:33:24,400
September brings the apple 
harvest. 

578
00:33:24,880 --> 00:33:28,120
Some varieties are for immediate
eating, while others are 

579
00:33:28,120 --> 00:33:31,520
specifically grown for storage. 
Because they're thick skins and 

580
00:33:31,520 --> 00:33:34,520
dense flesh, let them last until
spring in the root cellar. 

581
00:33:34,960 --> 00:33:37,400
Each preservation method gets 
matched to the food's 

582
00:33:37,400 --> 00:33:40,960
characteristics. 
Watery vegetables like cucumbers

583
00:33:40,960 --> 00:33:43,480
and green beans are better than 
they freeze because their 

584
00:33:43,480 --> 00:33:45,840
texture would be destroyed by 
ice crystals. 

585
00:33:46,440 --> 00:33:49,480
Berries freeze beautifully but 
make terrible canned goods 

586
00:33:49,480 --> 00:33:51,600
because the processing turns 
them to mush. 

587
00:33:52,280 --> 00:33:55,040
Apples can be dried into 
leathery rings that store 

588
00:33:55,040 --> 00:33:59,240
indefinitely, but pears become 
grainy when dried and work 

589
00:33:59,240 --> 00:34:03,080
better canned or fresh. 
Learning these matches takes 

590
00:34:03,080 --> 00:34:06,200
years of experience and 
generations of accumulated 

591
00:34:06,200 --> 00:34:09,440
knowledge about which techniques
work with which foods. 

592
00:34:09,679 --> 00:34:12,440
Fall is the storing season, when
the root cellar receives its 

593
00:34:12,440 --> 00:34:15,560
winter stock. 
Potatoes get dug after the first

594
00:34:15,560 --> 00:34:19,440
light frost kills the vines, but
before hard freezes damage the 

595
00:34:19,440 --> 00:34:21,920
tubers. 
They're left to dry in the field

596
00:34:21,920 --> 00:34:25,280
for a few hours, so dirt falls 
away easily, Then stored in 

597
00:34:25,280 --> 00:34:29,520
wooden boxes where air can 
circulate, carrots, beets, 

598
00:34:29,520 --> 00:34:33,520
turnips and parsnips can stay in
the ground until needed. 

599
00:34:34,120 --> 00:34:37,920
Soil is the perfect storage 
medium, but many get dug and 

600
00:34:37,920 --> 00:34:40,280
stored to avoid having to 
harvest in snow. 

601
00:34:41,159 --> 00:34:44,239
Winter squash get cured for two 
weeks at warm temperatures to 

602
00:34:44,239 --> 00:34:47,480
harden their skins before moving
to cool storage, where they'll 

603
00:34:47,480 --> 00:34:50,320
last through March. 
Winter means living off stored 

604
00:34:50,320 --> 00:34:53,520
goods and understanding scarcity
in ways that modern life has 

605
00:34:53,520 --> 00:34:56,440
forgotten. 
By February, the food available 

606
00:34:56,440 --> 00:34:58,400
is what you planned for months 
earlier. 

607
00:34:58,920 --> 00:35:02,440
If you didn't can enough 
tomatoes or Pickles, well, you 

608
00:35:02,440 --> 00:35:04,240
don't eat them until summer 
returns. 

609
00:35:04,600 --> 00:35:08,360
This isn't hardship but reality,
a natural consequence of 

610
00:35:08,360 --> 00:35:10,640
seasonal eating that creates 
anticipation. 

611
00:35:11,280 --> 00:35:13,760
The first strawberry of June 
tastes better when you haven't 

612
00:35:13,760 --> 00:35:15,440
eaten one since the previous 
June. 

613
00:35:16,080 --> 00:35:18,520
Fresh corn in August feels 
special when you've been eating 

614
00:35:18,520 --> 00:35:21,720
dried beans all winter. 
This seasonal rhythm creates a 

615
00:35:21,720 --> 00:35:24,960
different relationship with food
than what supermarkets offer. 

616
00:35:25,680 --> 00:35:28,520
You can't eat whatever you want 
whenever you want it, but you 

617
00:35:28,520 --> 00:35:32,560
also experience food at its peak
right after harvest, when 

618
00:35:32,560 --> 00:35:36,400
flavours are most intense. 
Modern preservation techniques 

619
00:35:36,400 --> 00:35:40,640
like canning and freezing are 
improvements on older methods, 

620
00:35:41,000 --> 00:35:43,720
but there's still improvements 
within a seasonal framework. 

621
00:35:43,720 --> 00:35:47,520
Rather than attempts to 
eliminate seasons entirely, the 

622
00:35:47,560 --> 00:35:50,960
Akhmish accept that tomatoes 
have a season, that fresh milk 

623
00:35:50,960 --> 00:35:54,280
production drops in winter, and 
that some foods simply aren't 

624
00:35:54,280 --> 00:35:57,640
available year round without 
heroic efforts they choose not 

625
00:35:57,640 --> 00:35:59,840
to make. 
The rhythm also creates 

626
00:35:59,840 --> 00:36:03,680
anticipation and variety. 
Just when you're tired of winter

627
00:36:03,680 --> 00:36:07,840
squash, spring greens arrive. 
Just when you're overwhelmed by 

628
00:36:07,840 --> 00:36:11,600
summer tomatoes, they stop 
producing and fall apples begin.

629
00:36:12,680 --> 00:36:15,960
This variety comes not from 
importing foods from different 

630
00:36:15,960 --> 00:36:19,240
climates, but from accepting 
what each season offers. 

631
00:36:19,840 --> 00:36:23,440
It's a less monotonous diet than
eating the same globally sourced

632
00:36:23,440 --> 00:36:27,000
foods year round, even if it's 
less immediately convenient. 

633
00:36:27,320 --> 00:36:30,440
Preserving food without 
electricity requires knowledge 

634
00:36:30,440 --> 00:36:33,800
that must be preserved just as 
carefully as the food itself. 

635
00:36:34,720 --> 00:36:37,720
This knowledge passes through 
generations, not through written

636
00:36:37,720 --> 00:36:41,920
instructions, but through 
experience, through watching and

637
00:36:41,920 --> 00:36:45,760
doing, and through the 
accumulated wisdom of success 

638
00:36:45,760 --> 00:36:49,080
and failure over decades. 
The young woman learns canning 

639
00:36:49,080 --> 00:36:52,800
from her mother, starting with 
simple recipes like applesauce 

640
00:36:52,800 --> 00:36:56,440
that forgive minor errors and 
graduating to more complex 

641
00:36:56,440 --> 00:37:00,200
preserves that require precise 
timing and temperature control. 

642
00:37:00,920 --> 00:37:03,720
She learns that you can tell 
when Jelly is done by how it 

643
00:37:03,720 --> 00:37:06,480
sheets off a spoon, that the 
temperature of the boiling 

644
00:37:06,480 --> 00:37:09,600
mixture matters but the visual 
cues matter more, and that 

645
00:37:09,600 --> 00:37:13,440
recipes are guidelines but 
experience is the real teacher. 

646
00:37:14,280 --> 00:37:17,280
These lessons can't be reduced 
to written instructions because 

647
00:37:17,280 --> 00:37:21,440
so much depends on variables 
that change the pectin content 

648
00:37:21,440 --> 00:37:25,400
of your particular apples, the 
humidity on canning day, and the

649
00:37:25,400 --> 00:37:28,360
exact heat distribution in your 
particular stove. 

650
00:37:28,800 --> 00:37:31,640
A young man learns rice 
harvesting from his father and 

651
00:37:31,640 --> 00:37:35,760
uncles, discovering through cold
hands and aching back how to saw

652
00:37:35,800 --> 00:37:39,280
blocks that are uniform enough 
to stack efficiently but not so 

653
00:37:39,280 --> 00:37:41,320
perfect that the effort wastes 
time. 

654
00:37:41,880 --> 00:37:43,960
He learns that ice quality 
matters. 

655
00:37:44,360 --> 00:37:47,400
Clear ice from the centre of the
pond stores better than cloudy 

656
00:37:47,400 --> 00:37:50,600
ice from near shore, that 
rushing the harvest because a 

657
00:37:50,600 --> 00:37:54,600
warm spell threatens can result 
in blocks too thin to last 

658
00:37:54,600 --> 00:37:57,760
through summer, and that the 
sawdust used for insulation 

659
00:37:57,760 --> 00:38:01,840
needs to be dry or it will 
compress and lose its insulating

660
00:38:01,840 --> 00:38:03,920
value. 
The knowledge includes 

661
00:38:03,920 --> 00:38:08,320
understanding failure modes, how
to recognise when a jar hasn't 

662
00:38:08,320 --> 00:38:12,480
sealed properly and needs 
reprocessing, what spoiled food 

663
00:38:12,480 --> 00:38:14,760
smells like before you've 
actually opened the jar and 

664
00:38:14,760 --> 00:38:18,920
exposed yourself to danger, how 
to tell if a potato in the root 

665
00:38:18,920 --> 00:38:22,800
cellar has started rotting and 
needs removing before it spreads

666
00:38:22,800 --> 00:38:26,080
to its neighbors. 
These negative lessons are as 

667
00:38:26,080 --> 00:38:30,040
important as positive ones 
because food preservation when 

668
00:38:30,040 --> 00:38:33,480
it fails can create food 
poisoning that kills. 

669
00:38:33,760 --> 00:38:36,600
Some knowledge is empirical 
rather than theoretical. 

670
00:38:37,200 --> 00:38:40,200
Nobody needs to know that 
Botulism spores can survive 

671
00:38:40,200 --> 00:38:43,840
boiling temperatures but die at 
240°. 

672
00:38:44,400 --> 00:38:47,440
They just need to know that low 
acid foods require pressure 

673
00:38:47,440 --> 00:38:49,440
canning rather than water bath 
canning. 

674
00:38:50,320 --> 00:38:52,720
Nobody needs to understand 
evaporative cooling 

675
00:38:52,720 --> 00:38:55,320
thermodynamics to use a spring 
house effectively. 

676
00:38:55,720 --> 00:38:59,040
They just need to know that milk
Crocs go in the water and butter

677
00:38:59,040 --> 00:39:02,800
Crocs go above it. 
The theory is interesting, but 

678
00:39:02,800 --> 00:39:05,960
the practice is what keeps food 
safe and family fed. 

679
00:39:06,280 --> 00:39:09,480
This knowledge also includes 
seasonal timing that's specific 

680
00:39:09,480 --> 00:39:12,640
to local climate. 
When to plant potatoes so they 

681
00:39:12,640 --> 00:39:15,960
mature before the 1st frost but 
late enough that they're not 

682
00:39:15,960 --> 00:39:18,000
sitting in soil. 
During the hottest part of 

683
00:39:18,000 --> 00:39:20,920
summer. 
When various apple varieties 

684
00:39:20,920 --> 00:39:24,360
ripen and which ones store well 
versus which ones should be 

685
00:39:24,360 --> 00:39:27,800
eaten fresh. 
When to expect the spring to run

686
00:39:27,800 --> 00:39:31,200
coldest, Usually April, When 
snowmelt still drains 

687
00:39:31,200 --> 00:39:35,760
underground, versus when it 
warms slightly late summer when 

688
00:39:35,760 --> 00:39:38,920
the aquifer has been warmed by 
months of precipitation. 

689
00:39:39,640 --> 00:39:43,480
These micro local details matter
enormously, but aren't written 

690
00:39:43,480 --> 00:39:45,920
in books. 
They're learned through years of

691
00:39:45,920 --> 00:39:48,200
observation and pass through 
conversation. 

692
00:39:48,520 --> 00:39:51,360
The knowledge system also 
includes community wisdom about 

693
00:39:51,360 --> 00:39:54,880
what works and what doesn't. 
If someone experiments with a 

694
00:39:54,880 --> 00:39:58,200
new preservation technique and 
it works brilliantly, that 

695
00:39:58,200 --> 00:40:00,800
information spreads through 
social networks. 

696
00:40:01,240 --> 00:40:03,720
Similarly, if someone tries 
something that fails 

697
00:40:03,720 --> 00:40:06,960
spectacularly, that becomes 
community knowledge too. 

698
00:40:07,600 --> 00:40:11,320
This collective learning speeds 
adaptation and prevents repeated

699
00:40:11,320 --> 00:40:13,600
mistakes. 
It's a form of cultural 

700
00:40:13,600 --> 00:40:16,880
evolution where successful 
techniques persist and 

701
00:40:16,880 --> 00:40:21,360
unsuccessful ones get abandoned 
or without any formal research 

702
00:40:21,360 --> 00:40:23,640
program or Extension Service 
guidance. 

703
00:40:23,960 --> 00:40:27,840
Interestingly, modern technology
hasn't completely eliminated 

704
00:40:27,840 --> 00:40:31,160
this traditional knowledge. 
Even among the Amish, gas 

705
00:40:31,160 --> 00:40:33,800
refrigerators still benefit from
traditional placement 

706
00:40:33,800 --> 00:40:36,720
strategies. 
Don't put them near heat sources

707
00:40:37,040 --> 00:40:39,960
and do allow air circulation 
around the cooling coils. 

708
00:40:40,520 --> 00:40:44,120
Root sellers still need periodic
checking for rot and proper 

709
00:40:44,120 --> 00:40:47,680
humidity management. 
Spring houses still require 

710
00:40:47,680 --> 00:40:50,600
maintenance of water channels 
and structural integrity. 

711
00:40:51,280 --> 00:40:54,360
The technology may have improved
in some areas, but the 

712
00:40:54,360 --> 00:40:57,960
underlying principles remain 
constant and understanding those

713
00:40:57,960 --> 00:41:00,800
principles matters more than 
understanding the specific 

714
00:41:00,800 --> 00:41:03,280
tools. 
As you stand here in this Amish 

715
00:41:03,280 --> 00:41:07,200
kitchen, dawn now fully arrived 
and the world waking around you,

716
00:41:07,920 --> 00:41:10,960
you might wonder what lessons 
translate from this life to your

717
00:41:10,960 --> 00:41:13,480
own. 
You're probably not going to dig

718
00:41:13,480 --> 00:41:16,160
a root cellar or harvest ice 
from a pond. 

719
00:41:16,840 --> 00:41:20,080
But the principles underlying 
these practices aren't strictly 

720
00:41:20,080 --> 00:41:22,840
about technology. 
They're about understanding 

721
00:41:22,840 --> 00:41:26,080
systems, planning ahead, and 
accepting limits. 

722
00:41:26,480 --> 00:41:29,000
The most obvious lesson is 
redundancy. 

723
00:41:29,680 --> 00:41:32,360
The Amish don't depend on a 
single preservation method, but 

724
00:41:32,360 --> 00:41:36,320
layer multiple approaches. 
Root Cellars for bulk storage, 

725
00:41:36,640 --> 00:41:40,560
spring houses for daily use 
items, ice houses for actual 

726
00:41:40,560 --> 00:41:44,880
freezing, canning for long term 
shelf stable goods, and gas 

727
00:41:44,880 --> 00:41:49,600
refrigerators for convenience. 
If one system fails, others 

728
00:41:49,600 --> 00:41:52,440
continue working. 
Compare this to modern 

729
00:41:52,440 --> 00:41:55,600
dependence on electric 
refrigeration, where a power 

730
00:41:55,600 --> 00:41:58,240
outage or mechanical failure 
means potentially losing 

731
00:41:58,240 --> 00:42:01,360
everything perishable. 
The Amish approach, while more 

732
00:42:01,360 --> 00:42:04,320
labour intensive, is also more 
resilient against individual 

733
00:42:04,320 --> 00:42:06,840
failures. 
Another lesson is the value of 

734
00:42:06,840 --> 00:42:10,160
passive systems. 
Root Cellars and spring houses 

735
00:42:10,160 --> 00:42:14,200
require no ongoing energy input.
Once built, they function 

736
00:42:14,200 --> 00:42:17,840
indefinitely without fuel or 
electricity, maintained only by 

737
00:42:17,840 --> 00:42:20,000
occasional cleaning and 
structural repairs. 

738
00:42:20,920 --> 00:42:24,480
Modern life tends toward active 
systems that solve problems 

739
00:42:24,480 --> 00:42:28,040
through continuous energy 
application, air conditioning, 

740
00:42:28,320 --> 00:42:32,600
refrigeration, and heating, all 
of which stop working the moment

741
00:42:32,600 --> 00:42:36,040
power fails. 
Passive systems continue 

742
00:42:36,040 --> 00:42:39,000
functioning regardless of 
external circumstances, 

743
00:42:39,440 --> 00:42:42,480
providing a baseline of 
performance that isn't dependent

744
00:42:42,480 --> 00:42:44,560
on supply chains or 
infrastructure. 

745
00:42:44,960 --> 00:42:47,520
The seasonal eating pattern 
enforced by traditional 

746
00:42:47,520 --> 00:42:49,880
preservation methods also offers
lessons. 

747
00:42:50,560 --> 00:42:53,680
Modern supermarkets provide year
round access to produce 

748
00:42:53,680 --> 00:42:57,200
regardless of season, which 
seems like pure gain until you 

749
00:42:57,200 --> 00:43:02,040
consider the costs, energy for 
transportation and storage, loss

750
00:43:02,040 --> 00:43:05,280
of flavour from early harvesting
to survive shipping, and 

751
00:43:05,280 --> 00:43:07,840
disconnection from local growing
patterns. 

752
00:43:08,560 --> 00:43:12,240
Eating seasonally doesn't 
require going full Amish, but it

753
00:43:12,240 --> 00:43:15,720
can mean prioritizing local 
foods during their peak season, 

754
00:43:16,080 --> 00:43:19,880
preserving some of that bounty 
for offseason use, and accepting

755
00:43:19,880 --> 00:43:22,600
that some foods are seasonal 
treats rather than everyday 

756
00:43:22,600 --> 00:43:24,880
staples. 
The knowledge preservation 

757
00:43:24,880 --> 00:43:27,680
aspect raises questions about 
skill maintenance in an 

758
00:43:27,680 --> 00:43:31,200
automated world. 
As convenience technologies 

759
00:43:31,200 --> 00:43:34,800
handle more tasks, the knowledge
of how to do things manually 

760
00:43:34,840 --> 00:43:37,800
atrophies. 
You might not need to know how 

761
00:43:37,800 --> 00:43:40,880
to can tomatoes until the day 
you want to preserve your garden

762
00:43:40,880 --> 00:43:44,440
harvest, and by then you've lost
access to the grandmother who 

763
00:43:44,440 --> 00:43:47,720
could have taught you. 
The Amish maintain these skills 

764
00:43:47,720 --> 00:43:51,400
through continuous practice, but
that practice only happens 

765
00:43:51,400 --> 00:43:53,360
because their lifestyle requires
it. 

766
00:43:53,920 --> 00:43:57,280
For the rest of us, maintaining 
traditional skills means making 

767
00:43:57,280 --> 00:44:01,120
deliberate choices to learn and 
practice them despite not 

768
00:44:01,120 --> 00:44:04,280
needing them for survival. 
The community aspect of 

769
00:44:04,280 --> 00:44:07,240
traditional preservation also 
translates beyond the Amish 

770
00:44:07,240 --> 00:44:10,440
context. 
Ice harvesting and large scale 

771
00:44:10,440 --> 00:44:14,520
canning aren't solo activities, 
but community events that build 

772
00:44:14,520 --> 00:44:16,680
social bonds while accomplishing
work. 

773
00:44:17,520 --> 00:44:20,600
Modern life's convenience often 
comes with isolation. 

774
00:44:21,240 --> 00:44:24,000
You can feed yourself entirely 
without ever interacting with 

775
00:44:24,000 --> 00:44:27,080
neighbors or sharing labour. 
There's nothing wrong with 

776
00:44:27,080 --> 00:44:30,800
convenience, but recognizing 
what's lost might inspire 

777
00:44:30,800 --> 00:44:33,760
finding other ways to build 
community connections. 

778
00:44:34,120 --> 00:44:37,280
The architectural lessons about 
passive cooling applied directly

779
00:44:37,280 --> 00:44:40,520
to modern construction. 
Houses can be oriented to 

780
00:44:40,520 --> 00:44:44,840
minimize solar gain, designed 
for cross ventilation, and built

781
00:44:44,840 --> 00:44:47,600
with thermal mass that moderates
temperature swings. 

782
00:44:48,400 --> 00:44:50,960
These principles work regardless
of whether you have air 

783
00:44:50,960 --> 00:44:53,480
conditioning. 
They simply make climate control

784
00:44:53,480 --> 00:44:55,480
easier and less energy 
intensive. 

785
00:44:56,160 --> 00:44:58,600
Modern building codes often 
ignore these traditional 

786
00:44:58,600 --> 00:45:01,640
principles in favour of 
mechanical systems, but there's 

787
00:45:01,640 --> 00:45:05,200
no reason you can't have both. 
Perhaps the deepest lesson is 

788
00:45:05,200 --> 00:45:08,800
about accepting constraints. 
The Amish choose limits that 

789
00:45:08,800 --> 00:45:10,760
might seem arbitrary from 
outside. 

790
00:45:11,120 --> 00:45:13,360
No electricity, no cars, no 
Internet. 

791
00:45:13,880 --> 00:45:16,800
But within those constraints, 
they've developed sophisticated 

792
00:45:16,800 --> 00:45:20,680
solutions to practical problems.
Modern life tends toward 

793
00:45:20,680 --> 00:45:24,200
eliminating constraints through 
technology, assuming that more 

794
00:45:24,200 --> 00:45:27,000
options and greater convenience 
are always improvements. 

795
00:45:27,520 --> 00:45:30,880
The Akhmish example suggests 
that sometimes constraints force

796
00:45:30,880 --> 00:45:34,800
creativity and build resilience 
in ways that unlimited options 

797
00:45:34,800 --> 00:45:37,120
don't. 
You'll notice that none of this 

798
00:45:37,120 --> 00:45:40,960
is actually about refrigeration.
Food preservation is the visible

799
00:45:40,960 --> 00:45:43,920
practice, but the underlying 
patterns are about living 

800
00:45:43,920 --> 00:45:48,040
deliberately, planning ahead, 
maintaining skills, building 

801
00:45:48,040 --> 00:45:50,760
community and understanding 
systems. 

802
00:45:51,760 --> 00:45:54,760
These principles apply whether 
you're storing potatoes in a 

803
00:45:54,760 --> 00:45:58,280
root cellar or organising your 
life in a city apartment. 

804
00:45:59,000 --> 00:46:03,080
The specific techniques might 
not transfer, but the mindset 

805
00:46:03,080 --> 00:46:06,280
does. 
Before we finish, let's sit with

806
00:46:06,280 --> 00:46:10,440
one uncomfortable thought. 
Modern refrigeration, for all 

807
00:46:10,440 --> 00:46:14,640
it's convenience, is fragile. 
Your refrigerator depends on 

808
00:46:14,640 --> 00:46:18,200
electricity flowing reliably, on
supply chains delivering 

809
00:46:18,200 --> 00:46:21,600
replacement parts, and on repair
technicians understanding 

810
00:46:21,600 --> 00:46:25,040
complex systems. 
When hurricanes knockout power 

811
00:46:25,040 --> 00:46:28,440
or ice storms down transmission 
lines, the weakness becomes 

812
00:46:28,440 --> 00:46:32,240
obvious. 
Food spoils, freezes thaw, and 

813
00:46:32,240 --> 00:46:35,320
suddenly those old preservation 
methods don't seem quite so 

814
00:46:35,320 --> 00:46:37,400
quaint. 
The Amish approach to food 

815
00:46:37,400 --> 00:46:39,960
preservation is resilient 
precisely because it doesn't 

816
00:46:39,960 --> 00:46:42,000
depend on infrastructure that 
can fail. 

817
00:46:42,480 --> 00:46:46,280
Earth doesn't stop being cool. 
Underground springs don't stop 

818
00:46:46,280 --> 00:46:49,160
flowing. 
Ice, once harvested, stays 

819
00:46:49,160 --> 00:46:51,960
frozen. 
If properly stored, canned goods

820
00:46:51,960 --> 00:46:54,680
remain safe on shelves. 
The techniques are 

821
00:46:54,680 --> 00:46:57,800
decentralised. 
Each household maintains its own

822
00:46:57,800 --> 00:47:01,080
systems rather than depending on
electrical grids that serve 

823
00:47:01,080 --> 00:47:04,520
thousands. 
This decentralisation means that

824
00:47:04,520 --> 00:47:07,160
problems can be local rather 
than catastrophic. 

825
00:47:07,560 --> 00:47:10,320
Consider what happens when your 
refrigerator breaks. 

826
00:47:11,080 --> 00:47:14,840
You call a repair service, wait 
days or weeks for parts, 

827
00:47:15,280 --> 00:47:19,400
possibly lose food if the timing
is bad, and pay several $100 for

828
00:47:19,400 --> 00:47:22,000
the fix. 
When an Amish root seller has a 

829
00:47:22,000 --> 00:47:25,640
problem, maybe a door seal fails
or drainage backs up. 

830
00:47:26,200 --> 00:47:31,120
The fix involves basic carpentry
or simple excavation skills that

831
00:47:31,120 --> 00:47:33,080
household members already 
possess. 

832
00:47:33,960 --> 00:47:36,880
The repair cost is measured in 
hours of labour rather than 

833
00:47:36,880 --> 00:47:39,560
speciality parts shipped from 
distant factories. 

834
00:47:39,920 --> 00:47:42,920
This resilience also applies to 
economic disruption. 

835
00:47:43,640 --> 00:47:46,480
If energy costs spike 
dramatically, modern 

836
00:47:46,480 --> 00:47:48,920
refrigeration becomes expensive 
to operate. 

837
00:47:49,480 --> 00:47:52,760
If your income drops and you 
can't afford the electricity 

838
00:47:52,760 --> 00:47:55,960
bill, that expensive 
refrigerator becomes a non 

839
00:47:55,960 --> 00:47:59,400
functional box. 
Traditional methods have minimal

840
00:47:59,400 --> 00:48:02,680
ongoing costs. 
No power bills, no maintenance 

841
00:48:02,680 --> 00:48:05,600
contracts, just occasional 
labour that you provide 

842
00:48:05,600 --> 00:48:08,160
yourself. 
In economic terms, they're 

843
00:48:08,160 --> 00:48:12,320
capital expenses rather than 
operating expenses, and once the

844
00:48:12,320 --> 00:48:15,040
initial investment is made, the 
ongoing burden nearly 

845
00:48:15,040 --> 00:48:17,400
disappears. 
The knowledge required for 

846
00:48:17,400 --> 00:48:20,560
traditional preservation is also
more resilient than dependence 

847
00:48:20,560 --> 00:48:23,720
on specialists. 
When you know how to can 

848
00:48:23,720 --> 00:48:26,920
vegetables or manage a root 
seller, you're not dependent on 

849
00:48:26,920 --> 00:48:29,080
experts being available and 
affordable. 

850
00:48:29,600 --> 00:48:32,760
The knowledge can be shared 
freely without patent concerns 

851
00:48:32,760 --> 00:48:36,440
or proprietary restrictions. 
It can be practised at a small 

852
00:48:36,440 --> 00:48:39,200
scale without requiring 
industrial infrastructure. 

853
00:48:39,800 --> 00:48:43,920
This makes it remarkably 
democratic, available to anyone 

854
00:48:43,920 --> 00:48:47,080
willing to invest the time to 
learn and the labour to execute.

855
00:48:47,560 --> 00:48:50,360
There's also resilience in the 
simplicity of the systems. 

856
00:48:50,960 --> 00:48:53,520
A root cellar has fewer points 
of failure than a modern 

857
00:48:53,520 --> 00:48:56,160
refrigerator. 
There's no compressor to burn 

858
00:48:56,160 --> 00:49:00,320
out, no electronic controls to 
malfunction and no refrigerant 

859
00:49:00,320 --> 00:49:03,160
to leak. 
The worst that typically happens

860
00:49:03,160 --> 00:49:05,720
is you need to re stack some 
stone or repair a door. 

861
00:49:06,320 --> 00:49:09,120
Compare this to modern 
appliances, where a failed 

862
00:49:09,120 --> 00:49:11,640
circuit board might mean 
replacing the entire unit 

863
00:49:11,920 --> 00:49:14,040
because repairs cost more than 
replacement. 

864
00:49:14,400 --> 00:49:16,960
This isn't an argument that 
everyone should abandoned modern

865
00:49:16,960 --> 00:49:19,640
refrigeration and dig root 
Cellars in their backyards. 

866
00:49:20,200 --> 00:49:22,880
Modern life has different 
requirements and constraints 

867
00:49:22,880 --> 00:49:26,600
than Amish life, and trying to 
copy their methods exactly would

868
00:49:26,600 --> 00:49:29,920
be impractical for most people. 
But understanding that 

869
00:49:29,920 --> 00:49:33,160
alternatives exist, that there 
are multiple ways to solve food 

870
00:49:33,160 --> 00:49:36,760
preservation problems, provides 
a kind of mental resilience, 

871
00:49:36,800 --> 00:49:41,200
even if you never act on it. 
Knowing you could, if necessary,

872
00:49:41,440 --> 00:49:43,800
preserve food without 
electricity makes you less 

873
00:49:43,800 --> 00:49:47,160
dependent and more confident, 
even if you never actually need 

874
00:49:47,160 --> 00:49:49,360
to do it. 
The kitchen has warmed as 

875
00:49:49,360 --> 00:49:52,480
morning progressed and the 
sounds of the day have fully 

876
00:49:52,480 --> 00:49:55,080
arrived. 
Chickens complaining in their 

877
00:49:55,080 --> 00:49:59,600
run, horses shifting in their 
stalls, and distant voices of 

878
00:49:59,600 --> 00:50:01,440
family members starting their 
work. 

879
00:50:02,320 --> 00:50:05,480
You've witnessed an alternative 
to modern food preservation. 

880
00:50:05,840 --> 00:50:09,000
Not better or worse, but 
different, optimised for 

881
00:50:09,000 --> 00:50:10,800
different values and 
constraints. 

882
00:50:11,160 --> 00:50:14,000
The Amish keep food cold without
electricity through a 

883
00:50:14,000 --> 00:50:17,200
combination of old techniques 
and careful adaptation. 

884
00:50:17,800 --> 00:50:20,320
Root Cellars that use Earth's 
stable temperature. 

885
00:50:20,640 --> 00:50:23,080
Spring houses that harness 
flowing water. 

886
00:50:23,520 --> 00:50:26,000
Ice houses that store winter for
summer use. 

887
00:50:26,400 --> 00:50:29,440
Gas refrigerators that avoid 
electrical grids. 

888
00:50:29,840 --> 00:50:32,000
Canning that makes food shelf 
stable. 

889
00:50:32,280 --> 00:50:35,240
An architectural design that 
keeps living spaces cool. 

890
00:50:36,240 --> 00:50:39,520
None of these techniques are 
particularly complex, but their 

891
00:50:39,520 --> 00:50:42,400
effective use requires 
knowledge, planning and labour 

892
00:50:42,400 --> 00:50:44,920
that modern life has largely 
automated away. 

893
00:50:45,280 --> 00:50:47,720
What makes these methods 
remarkable isn't their 

894
00:50:47,720 --> 00:50:50,920
quaintness, but their resilience
and sustainability. 

895
00:50:51,560 --> 00:50:54,480
They work independently of 
infrastructure that can fail, 

896
00:50:54,800 --> 00:50:58,000
they require minimal ongoing 
energy input, and they can be 

897
00:50:58,000 --> 00:51:01,440
maintained with basic skills 
rather than specialised 

898
00:51:01,440 --> 00:51:04,600
expertise. 
In an era increasingly concerned

899
00:51:04,600 --> 00:51:08,760
with grid reliability, energy 
costs and environmental impact, 

900
00:51:09,280 --> 00:51:12,560
there's something quietly 
revolutionary about systems that

901
00:51:12,560 --> 00:51:17,840
simply work year after year, 
asking nothing but attention and

902
00:51:17,840 --> 00:51:20,040
respect. 
As you prepare to leave this 

903
00:51:20,040 --> 00:51:23,240
kitchen and return to your 
electrically powered life, you 

904
00:51:23,240 --> 00:51:26,600
carry new knowledge about cold 
that it can be harvested from 

905
00:51:26,600 --> 00:51:30,000
winter and stored for summer. 
That earth itself is a 

906
00:51:30,000 --> 00:51:33,520
refrigerator if you dig deep 
enough, that flowing water 

907
00:51:33,520 --> 00:51:37,560
continuously creates coolness, 
and that food can be preserved 

908
00:51:37,560 --> 00:51:41,200
in dozens of ways that don't 
require continuous energy input.

909
00:51:42,200 --> 00:51:44,960
Whether you ever use this 
knowledge practically or simply 

910
00:51:44,960 --> 00:51:47,800
hold it as interesting 
background information, you now 

911
00:51:47,800 --> 00:51:50,760
understand that the particular 
solutions modern life chose 

912
00:51:50,760 --> 00:51:52,480
aren't the only possible 
solutions. 

913
00:51:52,800 --> 00:51:55,400
And sometimes the old ways 
persist because they work 

914
00:51:55,400 --> 00:51:58,080
remarkably well. 
The Amish aren't preserving 

915
00:51:58,080 --> 00:52:01,200
these techniques out of 
nostalgia or stubbornness, but 

916
00:52:01,200 --> 00:52:03,640
because they've chosen a 
different set of trade-offs, 

917
00:52:04,000 --> 00:52:08,000
valuing self-sufficiency, 
community, and independence from

918
00:52:08,000 --> 00:52:10,080
infrastructure over convenience 
and ease. 

919
00:52:10,960 --> 00:52:14,600
Their choices aren't available 
or desirable for everyone, but 

920
00:52:14,600 --> 00:52:17,840
they demonstrate that 
alternatives exist, that 

921
00:52:17,840 --> 00:52:20,920
technology isn't a one way 
ratchet where newer is always 

922
00:52:20,920 --> 00:52:25,320
better, and that sometimes the 
most sophisticated solution is 

923
00:52:25,320 --> 00:52:28,720
the one that works reliably with
minimal fuss for centuries. 

924
00:52:28,960 --> 00:52:32,560
So tonight, when you open your 
electric refrigerator and cool 

925
00:52:32,560 --> 00:52:35,920
air washes over your face, maybe
you'll think about the root 

926
00:52:35,920 --> 00:52:39,400
cellar dug into a hillside, the 
spring running cold through a 

927
00:52:39,400 --> 00:52:43,520
stone building, the ice blocks 
cut from frozen ponds, and the 

928
00:52:43,520 --> 00:52:46,480
gas refrigerator quietly 
absorbing heat through 

929
00:52:46,480 --> 00:52:49,360
chemistry. 
And maybe you'll appreciate that

930
00:52:49,360 --> 00:52:52,960
we live in a time when we can 
choose between many solutions to

931
00:52:52,960 --> 00:52:56,240
the same problem, when both 
ancient wisdom and modern 

932
00:52:56,240 --> 00:52:59,760
convenience are available, and 
when you can harvest cold from 

933
00:52:59,760 --> 00:53:02,200
the earth or summon it at the 
touch of a button. 

934
00:53:02,960 --> 00:53:05,640
Both work, both have their 
place. 

935
00:53:06,080 --> 00:53:09,600
And knowing both exist makes you
richer than knowing only one. 

936
00:53:09,920 --> 00:53:14,240
Sleep well, knowing that 
somewhere tonight, food stays 

937
00:53:14,240 --> 00:53:18,520
fresh in the earth's embrace, 
cooled by stone and water and 

938
00:53:18,520 --> 00:53:22,040
ice, preserved by methods that 
predate our grandparents. 

939
00:53:22,040 --> 00:53:26,440
Grandparents quietly working as 
they have for centuries, asking 

940
00:53:26,440 --> 00:53:28,840
nothing but what the land freely
provides. 

941
00:53:34,440 --> 00:53:36,880
Imagine nothing. 
Not darkness. 

942
00:53:37,280 --> 00:53:39,480
Darkness requires something to 
be dark. 

943
00:53:39,880 --> 00:53:43,320
Not silence. 
Silence requires space for sound

944
00:53:43,320 --> 00:53:46,520
to not fill. 
Just nothing. 

945
00:53:47,320 --> 00:53:51,880
And then, approximately 4.6 
billion years ago, in a rather 

946
00:53:51,880 --> 00:53:55,120
ordinary corner of an 
unremarkable Galaxy, a cloud of 

947
00:53:55,120 --> 00:53:57,920
dust and gas decided to do 
something interesting. 

948
00:53:58,240 --> 00:54:01,520
This wasn't a dramatic moment 
with cosmic fireworks and 

949
00:54:01,520 --> 00:54:05,160
celestial fanfare. 
It was more like watching cream 

950
00:54:05,160 --> 00:54:09,320
slowly swirl into coffee, except
the coffee was hydrogen and 

951
00:54:09,320 --> 00:54:13,200
helium, the cream was various 
elements forged in the bellies 

952
00:54:13,200 --> 00:54:16,680
of dead stars, and the whole 
thing was happening in the 

953
00:54:16,720 --> 00:54:20,880
absolute zero of space. 
The cloud began to collapse 

954
00:54:20,880 --> 00:54:25,120
under its own gravity, spinning 
faster as it contracted the way 

955
00:54:25,120 --> 00:54:28,240
an ice skater spins faster when 
pulling in their arms. 

956
00:54:28,680 --> 00:54:32,680
At the centre of this spinning 
cloud, material accumulated and 

957
00:54:32,680 --> 00:54:35,320
compressed until the pressure 
and temperature became so 

958
00:54:35,320 --> 00:54:39,200
intense that hydrogen atoms 
began fusing into helium. 

959
00:54:40,360 --> 00:54:44,720
Our sun flickered to life, not 
with a bang, but with a gradual 

960
00:54:44,720 --> 00:54:48,400
brightening, like someone slowly
turning up a dimmer switch. 

961
00:54:48,400 --> 00:54:51,440
Over the course of several 
million years around this 

962
00:54:51,440 --> 00:54:55,080
newborn star, the remaining dust
and gas continue to orbit, 

963
00:54:55,520 --> 00:54:59,040
occasionally bumping into other 
particles sticking together. 

964
00:54:59,040 --> 00:55:02,680
Through simple physics and 
patient accumulation, these 

965
00:55:02,680 --> 00:55:06,600
cosmic dust bunners grew larger,
their gravity pulling in a more 

966
00:55:06,600 --> 00:55:10,360
material, creating bodies that 
would eventually become planets.

967
00:55:11,000 --> 00:55:14,720
This process was less like 
construction and more like very 

968
00:55:14,720 --> 00:55:19,840
slow, very violent pottery, with
collisions serving as the 

969
00:55:19,840 --> 00:55:24,120
Potter's wheel about 4.54 
billion years ago, give or take 

970
00:55:24,120 --> 00:55:27,040
50 million years. 
Because geological dating isn't 

971
00:55:27,040 --> 00:55:30,480
an exact science at these 
scales, one of these 

972
00:55:30,480 --> 00:55:33,640
protoplanets had grown large 
enough to warrant its own name. 

973
00:55:34,160 --> 00:55:37,560
We call it Earth, though it bore
absolutely no resemblance to the

974
00:55:37,560 --> 00:55:39,080
planet you're sitting on right 
now. 

975
00:55:39,880 --> 00:55:43,640
Imagine taking everything lovely
about Earth, the blue oceans, 

976
00:55:43,640 --> 00:55:47,240
green forests and breathable 
atmosphere, and replacing it 

977
00:55:47,240 --> 00:55:50,240
with a ball of molten rock 
spinning through the void like 

978
00:55:50,240 --> 00:55:52,960
an angry ember. 
The young Earth was hot. 

979
00:55:53,760 --> 00:55:58,640
Not summer afternoon hot, not 
even surface of the sun hot, but

980
00:55:58,640 --> 00:56:01,640
hot enough to melt rock. 
Which is saying something. 

981
00:56:02,400 --> 00:56:07,680
The surface was covered in magma
oceans, vast expanses of liquid 

982
00:56:07,680 --> 00:56:11,120
rock that glowed red and orange 
like some hellish lava lamps 

983
00:56:11,120 --> 00:56:13,320
stretching from horizon to 
horizon. 

984
00:56:14,200 --> 00:56:17,800
The atmosphere, such as it was, 
consisted primarily of vaporized

985
00:56:17,800 --> 00:56:21,480
rock, some hydrogen, and various
gases that would have been 

986
00:56:21,480 --> 00:56:25,280
immediately fatal to any living 
thing had any living things 

987
00:56:25,280 --> 00:56:28,840
existed to be killed by them. 
This was a period of intense 

988
00:56:28,840 --> 00:56:32,840
bombardment when asteroids and 
comets pelted the young planet 

989
00:56:32,840 --> 00:56:37,040
with the regularity of rain. 
Each impact added mass, heat, 

990
00:56:37,040 --> 00:56:40,480
and occasionally interesting new
chemical compounds. 

991
00:56:41,080 --> 00:56:44,200
The larger impacts were 
spectacular events that would 

992
00:56:44,200 --> 00:56:47,800
have vaporized entire oceans if 
oceans had existed. 

993
00:56:48,640 --> 00:56:51,880
Fortunately, no one was around 
to worry about property values. 

994
00:56:52,240 --> 00:56:56,880
Then, roughly 4.5 billion years 
ago, something significant 

995
00:56:56,880 --> 00:56:59,720
happened. 
Another protoplanet, about the 

996
00:56:59,720 --> 00:57:03,160
size of Mars, was travelling on 
an orbital path that intersected

997
00:57:03,160 --> 00:57:05,680
with Earth's. 
The collision that followed was,

998
00:57:05,680 --> 00:57:08,680
by any measure, the most 
important traffic accident in 

999
00:57:08,680 --> 00:57:12,360
planetary history. 
The impact was so catastrophic 

1000
00:57:12,360 --> 00:57:16,320
that it vaporized the impactor 
and ejected enormous amounts of 

1001
00:57:16,320 --> 00:57:19,200
material from both bodies into 
orbit around Earth. 

1002
00:57:19,600 --> 00:57:23,160
This debris ring spinning around
the traumatized planet gradually

1003
00:57:23,160 --> 00:57:26,640
coalesced into our moon. 
Over millions of years, 

1004
00:57:26,640 --> 00:57:29,280
countless particles came 
together through the same 

1005
00:57:29,280 --> 00:57:32,680
patient gravitational processes 
that had formed Earth itself, 

1006
00:57:33,320 --> 00:57:36,240
creating a companion that would 
profoundly influence life on 

1007
00:57:36,240 --> 00:57:39,520
Earth in ways neither body could
have anticipated. 

1008
00:57:39,920 --> 00:57:42,360
The moon's formation had another
crucial effect. 

1009
00:57:42,880 --> 00:57:46,800
It stabilised Earth's rotation. 
Without this celestial 

1010
00:57:46,800 --> 00:57:50,640
companion, Earth would wobble 
chaotically on its axis like a 

1011
00:57:50,640 --> 00:57:54,600
spinning top, losing momentum, 
making consistent climate 

1012
00:57:54,600 --> 00:57:57,720
patterns nearly impossible. 
The moon, through its 

1013
00:57:57,720 --> 00:58:00,800
gravitational influence, gave 
Earth the steady rotation that 

1014
00:58:00,800 --> 00:58:04,080
would eventually allow for 
predictable seasons, though it 

1015
00:58:04,080 --> 00:58:07,120
would be billions of years 
before anything existed to 

1016
00:58:07,120 --> 00:58:10,640
appreciate spring or autumn. 
As the bombardment gradually 

1017
00:58:10,640 --> 00:58:14,520
decreased and the surface began 
to cool, the character of Earth 

1018
00:58:14,520 --> 00:58:18,280
started to change. 
Instead of a uniform sphere of 

1019
00:58:18,280 --> 00:58:21,640
molten rock, differentiation 
began to occur. 

1020
00:58:22,360 --> 00:58:26,160
Heavier elements like iron and 
nickel sank toward the centre, 

1021
00:58:26,560 --> 00:58:31,320
creating Earth's dense core. 
Lighter materials rose toward 

1022
00:58:31,320 --> 00:58:34,160
the surface, forming the 
beginnings of what would 

1023
00:58:34,160 --> 00:58:38,400
eventually become the crust. 
It was like watching a cosmic 

1024
00:58:38,400 --> 00:58:42,600
separation similar to oil and 
vinegar settling in salad 

1025
00:58:42,600 --> 00:58:45,120
dressing, except on a planetary 
scale. 

1026
00:58:45,120 --> 00:58:48,080
And over millions of years, the 
cooling continued. 

1027
00:58:48,480 --> 00:58:51,280
The cooling is relative when 
discussing something that starts

1028
00:58:51,280 --> 00:58:54,920
as molten rock that the surface 
temperature dropped below the 

1029
00:58:54,920 --> 00:58:57,760
melting point of various 
minerals, allowing the first 

1030
00:58:57,760 --> 00:59:02,480
solid crust to form. 
This crust was thin, unstable, 

1031
00:59:02,720 --> 00:59:05,560
and constantly recycled by the 
convection currents in the 

1032
00:59:05,560 --> 00:59:10,560
mantle below, but it represented
something genuinely new, solid 

1033
00:59:10,560 --> 00:59:12,720
ground. 
Yet the planet remained 

1034
00:59:12,720 --> 00:59:16,480
profoundly inhospitable. 
The atmosphere was thick with 

1035
00:59:16,480 --> 00:59:20,600
carbon dioxide and water vapour,
creating a greenhouse effect 

1036
00:59:20,600 --> 00:59:23,280
that kept surface temperatures 
at levels that would have felt 

1037
00:59:23,280 --> 00:59:26,720
comfortable only to the molten 
rock that still occasionally 

1038
00:59:26,720 --> 00:59:29,360
breached the surface through 
volcanic activity. 

1039
00:59:30,480 --> 00:59:34,640
Lightning storms of incredible 
violence split the sky, caused 

1040
00:59:34,640 --> 00:59:37,360
by the interaction of volcanic 
gases and atmospheric 

1041
00:59:37,360 --> 00:59:41,280
turbulence. 
The landscape was barren, dark 

1042
00:59:41,560 --> 00:59:45,040
and dotted with active volcanoes
that regularly resurfaced the 

1043
00:59:45,040 --> 00:59:48,480
thin crust with fresh lava. 
But within this violence, 

1044
00:59:48,480 --> 00:59:50,240
something remarkable was 
occurring. 

1045
00:59:50,720 --> 00:59:54,200
The volcanic activity that made 
the surface so hostile was also 

1046
00:59:54,200 --> 00:59:57,080
releasing water vapour that had 
been locked in the planet's 

1047
00:59:57,080 --> 00:59:59,920
interior. 
This water vapour rose into the 

1048
00:59:59,920 --> 01:00:02,720
atmosphere, gradually 
accumulating until the 

1049
01:00:02,720 --> 01:00:04,640
atmosphere became saturated with
it. 

1050
01:00:05,120 --> 01:00:09,000
Like a sponge that can hold no 
more liquid, the stage was being

1051
01:00:09,000 --> 01:00:11,960
set for the next great 
transformation, though it would 

1052
01:00:11,960 --> 01:00:16,000
require patience, the kind of 
patience that only geology 

1053
01:00:16,000 --> 01:00:18,480
possesses. 
Picture the moment when Earth's 

1054
01:00:18,480 --> 01:00:21,680
atmosphere finally cooled enough
for something magical to happen.

1055
01:00:23,000 --> 01:00:26,120
After millions of years of 
accumulation, the water vapour 

1056
01:00:26,120 --> 01:00:28,400
in the atmosphere reached a 
critical threshold. 

1057
01:00:29,080 --> 01:00:32,480
For the first time in planetary 
history, the surface temperature

1058
01:00:32,480 --> 01:00:35,080
dropped below the boiling point 
of water at atmospheric 

1059
01:00:35,080 --> 01:00:38,320
pressure. 
What happened next was quite 

1060
01:00:38,320 --> 01:00:41,360
literally the longest rainstorm 
in Earth's history. 

1061
01:00:41,720 --> 01:00:44,960
It rained and it rained and it 
rained some more. 

1062
01:00:45,320 --> 01:00:48,480
This wasn't a spring shower or 
even a monsoon season. 

1063
01:00:49,120 --> 01:00:51,240
This was a rain event that 
lasted. 

1064
01:00:51,600 --> 01:00:54,960
And here's where geology's sense
of time becomes almost comical. 

1065
01:00:55,520 --> 01:00:59,680
Possibly thousands of years. 
Imagine setting your watch for 

1066
01:00:59,680 --> 01:01:02,440
the beginning of recorded human 
history and watching it rain 

1067
01:01:02,440 --> 01:01:05,520
constantly until today. 
That gives you a sense of the 

1068
01:01:05,520 --> 01:01:09,200
scale we're discussing. 
The water fell on rocks so hot 

1069
01:01:09,200 --> 01:01:12,240
it instantly vaporized, shooting
back into the atmosphere of 

1070
01:01:12,240 --> 01:01:14,720
steam. 
But each time this happened, the

1071
01:01:14,720 --> 01:01:18,040
rock cooled slightly. 
Eventually, after countless 

1072
01:01:18,040 --> 01:01:22,200
cycles of rain, evaporation, and
more rain, the surface 

1073
01:01:22,200 --> 01:01:24,600
temperature dropped enough for 
water to remain liquid. 

1074
01:01:25,400 --> 01:01:29,680
The first puddles formed, then 
pools, then seas, and finally 

1075
01:01:29,680 --> 01:01:32,880
vast oceans that covered much of
the planet's surface. 

1076
01:01:33,280 --> 01:01:36,600
These early oceans were nothing 
like the sparkling blue waters 

1077
01:01:36,600 --> 01:01:40,800
you might visit on vacation. 
They were hot, perhaps close to 

1078
01:01:40,800 --> 01:01:42,720
the boiling point in many 
places. 

1079
01:01:43,320 --> 01:01:46,520
They were acidic and rich in 
dissolved minerals and gases 

1080
01:01:46,520 --> 01:01:50,440
from volcanic activity. 
The water was likely greenish 

1081
01:01:50,440 --> 01:01:54,360
brown or grey, coloured by 
dissolved iron and other metals.

1082
01:01:55,160 --> 01:01:58,160
If you could somehow have stood 
on the shore of this primordial 

1083
01:01:58,160 --> 01:02:01,480
ocean, you would have seen a 
scene from a science fiction 

1084
01:02:01,480 --> 01:02:04,800
nightmare. 
Steaming waters under a thick 

1085
01:02:04,800 --> 01:02:08,760
orange grey atmosphere, with 
volcanic islands dotting the 

1086
01:02:08,760 --> 01:02:12,880
horizon and lightning constantly
illuminating the clouds. 

1087
01:02:13,200 --> 01:02:16,240
Yet these hostile waters were 
paradoxically preparing to 

1088
01:02:16,240 --> 01:02:18,440
become the birth place of all 
life on Earth. 

1089
01:02:19,080 --> 01:02:22,680
The ocean served as a vast 
chemical laboratory, mixing 

1090
01:02:22,680 --> 01:02:25,480
minerals from the rocks with 
gases from the atmosphere and 

1091
01:02:25,480 --> 01:02:29,600
energy from volcanic vents, 
lightning, and the fierce 

1092
01:02:29,600 --> 01:02:32,880
ultraviolet radiation that 
penetrated the early atmosphere.

1093
01:02:33,560 --> 01:02:37,160
In tide pools and near 
hydrothermal vents, complex 

1094
01:02:37,160 --> 01:02:39,320
chemical reactions began to 
occur. 

1095
01:02:39,640 --> 01:02:43,040
The early Earth had no oxygen in
its atmosphere, at least not 

1096
01:02:43,040 --> 01:02:47,160
molecular oxygen as we know it. 
This would have been immediately

1097
01:02:47,160 --> 01:02:50,680
fatal to most modern organisms, 
but it created perfect 

1098
01:02:50,680 --> 01:02:53,560
conditions for the chemistry 
that would eventually lead to 

1099
01:02:53,560 --> 01:02:57,000
life. 
Without oxygen to break down 

1100
01:02:57,000 --> 01:03:00,520
organic molecules, complex 
carbon compounds could 

1101
01:03:00,520 --> 01:03:03,440
accumulate and interact in ways 
that wouldn't be possible in 

1102
01:03:03,440 --> 01:03:07,120
today's oxidizing atmosphere. 
Water itself was the crucial 

1103
01:03:07,120 --> 01:03:10,400
ingredient. 
Water is an extraordinary 

1104
01:03:10,400 --> 01:03:14,640
solvent, capable of dissolving 
and transporting A remarkable 

1105
01:03:14,640 --> 01:03:18,920
range of chemical compounds. 
It facilitates reactions that 

1106
01:03:18,920 --> 01:03:22,200
would be impossible in dry 
conditions, it's unique 

1107
01:03:22,200 --> 01:03:26,600
properties expanding when 
frozen, having high surface 

1108
01:03:26,600 --> 01:03:30,360
tension. 
Being most dense at 4°C rather 

1109
01:03:30,360 --> 01:03:34,880
than at its freezing point would
prove essential for life, though

1110
01:03:34,880 --> 01:03:37,480
this wouldn't become apparent 
for hundreds of millions of 

1111
01:03:37,480 --> 01:03:40,360
years. 
The formation of stable oceans 

1112
01:03:40,360 --> 01:03:43,640
marked another crucial 
development, the water cycle. 

1113
01:03:44,400 --> 01:03:48,400
Water evaporated from the 
oceans, formed clouds, fellas 

1114
01:03:48,400 --> 01:03:51,920
rain on the continents, and 
flowed back to the seas through 

1115
01:03:51,920 --> 01:03:55,240
rivers and streams. 
This cycle would eventually 

1116
01:03:55,240 --> 01:03:58,040
become one of Earth's most 
important processes for 

1117
01:03:58,040 --> 01:04:02,280
distributing heat, shaping the 
landscape, and creating diverse 

1118
01:04:02,280 --> 01:04:04,200
environments where life could 
thrive. 

1119
01:04:04,600 --> 01:04:07,360
But the early Earth's surface 
was still dramatically different

1120
01:04:07,360 --> 01:04:10,080
from today. 
There were no continents as we 

1121
01:04:10,080 --> 01:04:13,960
understand them, no vast land 
masses with diverse geography. 

1122
01:04:14,520 --> 01:04:18,520
Instead, volcanic islands and 
small proto continents rose 

1123
01:04:18,520 --> 01:04:21,920
above the ocean surface, 
constantly being reshaped by 

1124
01:04:21,920 --> 01:04:25,600
ongoing volcanic activity and 
the earliest forms of plate 

1125
01:04:25,600 --> 01:04:28,680
tectonics. 
These land masses were barren 

1126
01:04:28,680 --> 01:04:32,920
rock, weathering slowly under 
the assault of acidic rain and 

1127
01:04:32,920 --> 01:04:35,840
being ground down by the 
mechanical action of waves and 

1128
01:04:35,840 --> 01:04:38,560
temperature changes. 
This weathering process was 

1129
01:04:38,560 --> 01:04:42,160
crucial for what came next. 
As rocks broke down, they 

1130
01:04:42,160 --> 01:04:45,480
released minerals into the 
oceans, enriching the chemical 

1131
01:04:45,480 --> 01:04:49,160
soup that filled Earth's seas. 
Essential elements like 

1132
01:04:49,160 --> 01:04:53,240
phosphorus, sulphur, and various
trace metals dissolved into the 

1133
01:04:53,240 --> 01:04:56,200
water, creating the diverse 
chemical environment that life 

1134
01:04:56,200 --> 01:04:59,360
would eventually require. 
The sea floor during this period

1135
01:04:59,360 --> 01:05:04,040
was a landscape of extremes. 
Hydrothermal vents punctured the

1136
01:05:04,040 --> 01:05:08,000
ocean floor, releasing super 
heated water rich in dissolved 

1137
01:05:08,000 --> 01:05:12,080
minerals and gases. 
Around these vents, chemical 

1138
01:05:12,080 --> 01:05:15,440
gradients created zones where 
different reactions could occur.

1139
01:05:16,160 --> 01:05:19,640
Some scientists believe these 
vents, where hot, mineral rich 

1140
01:05:19,640 --> 01:05:23,760
water mixed with cooler seawater
may have provided the energy and

1141
01:05:23,760 --> 01:05:26,800
chemical conditions necessary 
for the first living things to 

1142
01:05:26,800 --> 01:05:29,120
emerge. 
The atmosphere was gradually 

1143
01:05:29,120 --> 01:05:32,920
changing as well as carbon 
dioxide dissolved in the oceans 

1144
01:05:32,920 --> 01:05:35,600
and reacted with minerals to 
form carbonate rocks. 

1145
01:05:36,120 --> 01:05:39,320
Atmospheric CO2 levels slowly 
decreased. 

1146
01:05:39,920 --> 01:05:42,920
This gradually reduced the 
greenhouse effect, allowing 

1147
01:05:42,920 --> 01:05:46,680
temperatures to cool further. 
It was a negative feedback loop 

1148
01:05:46,680 --> 01:05:49,160
that would eventually help 
stabilize Earth's climate, 

1149
01:05:49,800 --> 01:05:52,840
though eventually means over 
hundreds of millions of years. 

1150
01:05:53,200 --> 01:05:56,360
During this era, the moon was 
much closer to Earth than it is 

1151
01:05:56,360 --> 01:05:59,320
today, perhaps half its current 
distance. 

1152
01:06:00,040 --> 01:06:03,920
This proximity created tides of 
almost unimaginable power. 

1153
01:06:04,640 --> 01:06:07,920
Twice daily, the ocean would 
surge and retreat across vast 

1154
01:06:07,920 --> 01:06:11,760
stretches of shoreline, driven 
by gravitational forces far 

1155
01:06:11,760 --> 01:06:15,840
stronger than today's tides. 
These powerful tides created 

1156
01:06:15,840 --> 01:06:19,160
dynamic transitional zones 
between ocean and land 

1157
01:06:19,560 --> 01:06:23,320
environments where water, air 
and rock constantly interacted. 

1158
01:06:23,760 --> 01:06:26,600
These tidal zones may have been 
crucibles for early chemical 

1159
01:06:26,600 --> 01:06:29,640
evolution. 
The repeated cycles of wetting 

1160
01:06:29,640 --> 01:06:33,320
and drying and heating and 
cooling created conditions where

1161
01:06:33,320 --> 01:06:37,720
complex molecules could form, 
concentrate and interact in ways

1162
01:06:37,720 --> 01:06:40,000
that might not occur in open 
water. 

1163
01:06:40,880 --> 01:06:44,400
In the pools left behind by 
retreating tides, organic 

1164
01:06:44,400 --> 01:06:47,720
compounds could accumulate and 
undergo reactions driven by 

1165
01:06:47,720 --> 01:06:51,920
sunlight, heat from nearby 
volcanic activity, and the 

1166
01:06:51,920 --> 01:06:55,120
simple mechanics of evaporation 
and concentration. 

1167
01:06:55,480 --> 01:06:59,520
The stage was set. 
Earth now had stable oceans, a 

1168
01:06:59,520 --> 01:07:03,720
recycling water cycle, diverse 
chemical environments, and 

1169
01:07:03,720 --> 01:07:07,760
energy sources ranging from 
volcanic heat to ultraviolet 

1170
01:07:07,760 --> 01:07:11,800
radiation. 
In the cosmic sense, the planet 

1171
01:07:11,800 --> 01:07:15,440
was ready for its most important
transition from a world of 

1172
01:07:15,440 --> 01:07:19,160
chemistry to a world of biology.
Though no one was waiting and 

1173
01:07:19,160 --> 01:07:22,000
nothing was planned, the 
conditions were right for 

1174
01:07:22,000 --> 01:07:25,560
something unprecedented in the 
known universe, the emergence of

1175
01:07:25,560 --> 01:07:29,360
life somewhere around 3.8 to 4 
billion years ago. 

1176
01:07:30,000 --> 01:07:32,640
And please forgive the 
imprecision, but we're trying to

1177
01:07:32,640 --> 01:07:35,720
date events that left barely a 
chemical whisper in the rocks. 

1178
01:07:36,080 --> 01:07:40,360
Something extraordinary happened
in some warm pool, or near some 

1179
01:07:40,360 --> 01:07:43,880
hydrothermal vent, or in some 
other environment we might never

1180
01:07:43,880 --> 01:07:48,240
definitively identify. 
Chemistry became biology. 

1181
01:07:48,600 --> 01:07:51,400
We need to be honest here. 
We don't know exactly how this 

1182
01:07:51,400 --> 01:07:54,240
happened. 
Scientists have proposed various

1183
01:07:54,240 --> 01:07:59,000
scenarios, the primordial soup 
hypothesis, the metabolism first

1184
01:07:59,000 --> 01:08:03,400
theory, and the RNA world 
concept, but the truth is that 

1185
01:08:03,400 --> 01:08:06,480
the origin of life remains one 
of science's most fascinating 

1186
01:08:06,480 --> 01:08:10,240
unsolved mysteries. 
What we do know is that at some 

1187
01:08:10,240 --> 01:08:13,200
point, chemical systems began to
do something they hadn't done 

1188
01:08:13,200 --> 01:08:15,400
before. 
They began to reproduce 

1189
01:08:15,400 --> 01:08:18,279
themselves. 
Imagine the first living thing, 

1190
01:08:18,279 --> 01:08:21,279
if we can even call it that. 
It wasn't a cell as we'd 

1191
01:08:21,279 --> 01:08:24,880
recognise 1 today, with all the 
complex machinery that even the 

1192
01:08:24,880 --> 01:08:28,520
simplest modern bacteria 
possess, it was probably 

1193
01:08:28,520 --> 01:08:32,720
something much simpler, perhaps 
just a self replicating molecule

1194
01:08:33,040 --> 01:08:36,200
enclosed in some kind of 
membrane that separated it from 

1195
01:08:36,200 --> 01:08:40,279
its environment. 
This humble beginning, this 

1196
01:08:40,279 --> 01:08:43,880
first tentative step from 
chemistry to biology, was 

1197
01:08:43,880 --> 01:08:46,960
arguably the most important 
moment in Earth's history. 

1198
01:08:47,359 --> 01:08:50,399
These first life forms, whatever
they were, would have been 

1199
01:08:50,399 --> 01:08:53,120
extraordinarily simple by modern
standards. 

1200
01:08:53,600 --> 01:08:57,240
They didn't photosynthesize, 
didn't respirate oxygen, which 

1201
01:08:57,240 --> 01:09:00,520
didn't exist in the atmosphere 
anyway, and probably didn't do 

1202
01:09:00,520 --> 01:09:03,319
much of anything except the bare
minimum required to maintain 

1203
01:09:03,319 --> 01:09:05,600
their existence and occasionally
reproduce. 

1204
01:09:06,319 --> 01:09:09,680
Yet they possess something that 
no mere chemical reaction has 

1205
01:09:10,200 --> 01:09:12,920
the ability to pass information 
to their descendants. 

1206
01:09:13,319 --> 01:09:17,479
Life, even in its most primitive
form, involves information. 

1207
01:09:18,200 --> 01:09:21,920
The first living things carried 
instructions, probably in the 

1208
01:09:21,920 --> 01:09:25,800
form of RNA or something RNA 
like that determined their 

1209
01:09:25,800 --> 01:09:29,000
structure and function. 
When they reproduced, they 

1210
01:09:29,000 --> 01:09:32,680
copied these instructions, and 
occasionally the copying process

1211
01:09:32,680 --> 01:09:36,000
introduced errors. 
Most errors were harmful, 

1212
01:09:36,319 --> 01:09:39,319
causing the offspring to 
function poorly or not at all, 

1213
01:09:40,040 --> 01:09:43,720
but occasionally, purely by 
chance, an error would produce 

1214
01:09:43,720 --> 01:09:46,160
something that worked slightly 
better under the existing 

1215
01:09:46,160 --> 01:09:49,479
conditions. 
This is evolution in its purest 

1216
01:09:49,479 --> 01:09:53,960
form, random variation combined 
with non random selection. 

1217
01:09:54,520 --> 01:09:57,240
The organisms that functioned 
better in their environment were

1218
01:09:57,240 --> 01:10:00,360
more likely to survive and 
reproduce, passing their 

1219
01:10:00,360 --> 01:10:03,280
advantageous characteristics to 
their descendants. 

1220
01:10:03,920 --> 01:10:07,200
Over millions of years, this 
simple process would transform 

1221
01:10:07,200 --> 01:10:11,480
simple replicating molecules 
into the astonishing diversity 

1222
01:10:11,480 --> 01:10:14,680
of life we see today. 
The early biosphere, if we can 

1223
01:10:14,680 --> 01:10:17,000
call it that, was entirely 
microbial. 

1224
01:10:17,720 --> 01:10:20,560
For more than a billion years, 
Earth was a planet of 

1225
01:10:20,560 --> 01:10:24,600
microscopic organisms living in 
the oceans, in rocks, and 

1226
01:10:24,600 --> 01:10:27,280
possibly in the thin film of 
moisture that occasionally 

1227
01:10:27,280 --> 01:10:30,600
covered land surfaces. 
These organisms were all 

1228
01:10:30,600 --> 01:10:34,840
prokaryotes, cells without a 
nucleus or other membrane bound 

1229
01:10:34,840 --> 01:10:37,280
organelles. 
They were simpler than any 

1230
01:10:37,280 --> 01:10:41,160
modern cell, yet they were 
alive, metabolising, reproducing

1231
01:10:41,160 --> 01:10:43,400
and slowly imperceptible 
changing. 

1232
01:10:43,760 --> 01:10:46,920
These early microbes developed 
various strategies for obtaining

1233
01:10:46,920 --> 01:10:49,760
energy. 
Some probably fed on organic 

1234
01:10:49,760 --> 01:10:52,720
molecules that formed through 
non biological chemical 

1235
01:10:52,720 --> 01:10:55,800
reactions. 
Others might have used chemical 

1236
01:10:55,800 --> 01:10:59,240
gradients around hydrothermal 
vents to power their metabolism.

1237
01:10:59,800 --> 01:11:02,680
Still others developed the 
ability to use sunlight to drive

1238
01:11:02,680 --> 01:11:06,280
chemical reactions, though these
early forms of photosynthesis 

1239
01:11:06,280 --> 01:11:08,840
were quite different from the 
oxygen producing version we're 

1240
01:11:08,840 --> 01:11:11,840
familiar with today. 
The ocean during this era would 

1241
01:11:11,840 --> 01:11:14,720
have looked alien. 
To modernize, the water had a 

1242
01:11:14,720 --> 01:11:18,320
distinctly different colour, 
perhaps greenish brown from 

1243
01:11:18,320 --> 01:11:21,600
dissolved iron, or tinged with 
other colours from various 

1244
01:11:21,600 --> 01:11:24,880
dissolved minerals. 
The atmosphere above was still 

1245
01:11:24,880 --> 01:11:29,280
dominated by carbon dioxide, 
nitrogen and water vapour, with 

1246
01:11:29,280 --> 01:11:32,920
little or no oxygen. 
Ultraviolet radiation from the 

1247
01:11:32,920 --> 01:11:36,560
sun beat down on the surface 
with an intensity that would be 

1248
01:11:36,560 --> 01:11:40,680
lethal to most modern organisms,
since there was no ozone layer 

1249
01:11:40,680 --> 01:11:43,840
to filter it out. 
Yet life persisted and gradually

1250
01:11:43,840 --> 01:11:48,000
became more sophisticated. 
Somewhere around 3.5 billion 

1251
01:11:48,000 --> 01:11:51,000
years ago, microbes began 
building structures called 

1252
01:11:51,000 --> 01:11:56,440
stromatolites, layered mounds of
sediment and microbial mats that

1253
01:11:56,440 --> 01:11:59,520
we can still see fossilized in 
rocks of appropriate age. 

1254
01:12:00,280 --> 01:12:03,560
These stromatolites were among 
our best evidence for early life

1255
01:12:03,960 --> 01:12:08,120
preserved communities of 
microorganisms that grew, died, 

1256
01:12:08,400 --> 01:12:12,120
and were covered by sediment, 
only to be colonised by new 

1257
01:12:12,120 --> 01:12:14,960
generations of microbes that 
repeated the process. 

1258
01:12:15,240 --> 01:12:19,360
If you'd visited A stromatolite 
covered shore 3.5 billion years 

1259
01:12:19,360 --> 01:12:23,320
ago, you might have seen low, 
rounded mounds rising from the 

1260
01:12:23,320 --> 01:12:26,560
shallow water, their surfaces 
covered with a greenish or 

1261
01:12:26,560 --> 01:12:29,880
brownish slime. 
Maps of microbes living in 

1262
01:12:29,880 --> 01:12:33,680
communities, each species 
occupying its preferred depth 

1263
01:12:33,680 --> 01:12:37,240
based on its tolerance for 
light, oxygen, and various 

1264
01:12:37,240 --> 01:12:40,560
chemical compounds. 
These were Earth's first 

1265
01:12:40,560 --> 01:12:44,720
ecosystems, communities of 
organisms interacting with each 

1266
01:12:44,720 --> 01:12:48,000
other and their environment in 
ways that transformed both. 

1267
01:12:48,400 --> 01:12:50,840
The development of 
photosynthesis was a crucial 

1268
01:12:50,840 --> 01:12:54,040
milestone, though it happened 
gradually and in stages. 

1269
01:12:54,800 --> 01:12:58,560
Early photosynthetic organisms 
used hydrogen sulphide or other 

1270
01:12:58,560 --> 01:13:01,400
compounds as an electron source 
rather than water. 

1271
01:13:02,080 --> 01:13:05,320
They produce sulphur or other 
byproducts rather than oxygen. 

1272
01:13:06,000 --> 01:13:09,720
These organisms could harvest 
energy from sunlight, using it 

1273
01:13:09,720 --> 01:13:12,880
to convert carbon dioxide into 
organic compounds. 

1274
01:13:13,520 --> 01:13:16,440
It was a neat trick that gave 
photosynthetic organisms a 

1275
01:13:16,440 --> 01:13:20,440
significant advantage over those
that relied on chemical energy 

1276
01:13:20,440 --> 01:13:24,240
sources. 
But then, probably around 2.7 to

1277
01:13:24,240 --> 01:13:28,200
2.5 billion years ago, something
revolutionary occurred. 

1278
01:13:28,880 --> 01:13:31,880
Some microbes, probably 
ancestors of modern 

1279
01:13:31,880 --> 01:13:35,440
cyanobacteria, evolved the 
ability to use water as an 

1280
01:13:35,440 --> 01:13:37,600
electron source for 
photosynthesis. 

1281
01:13:38,320 --> 01:13:41,480
This was a genuine innovation 
because water is abundant, 

1282
01:13:42,040 --> 01:13:45,680
unlike hydrogen sulphide, which 
is limited to specific 

1283
01:13:45,680 --> 01:13:47,960
environments like hydrothermal 
vents. 

1284
01:13:48,440 --> 01:13:50,960
There was just one small problem
with this new form of 

1285
01:13:50,960 --> 01:13:54,240
photosynthesis. 
It produced oxygen as a waste 

1286
01:13:54,240 --> 01:13:57,000
product. 
Oxygen is wonderful stuff if 

1287
01:13:57,000 --> 01:13:59,160
you're an Organism that has 
evolved to use it. 

1288
01:13:59,600 --> 01:14:03,200
It's extraordinarily reactive, 
which makes it perfect for 

1289
01:14:03,200 --> 01:14:05,920
extracting energy from food 
molecules efficiently. 

1290
01:14:06,400 --> 01:14:08,520
Aerobic metabolism. 
Respiration. 

1291
01:14:08,520 --> 01:14:12,600
Using oxygen yields far more 
energy per glucose molecule than

1292
01:14:12,600 --> 01:14:14,600
any form of anaerobic 
metabolism. 

1293
01:14:15,000 --> 01:14:18,720
It's the difference between 
getting 15 miles per gallon and 

1294
01:14:18,720 --> 01:14:22,040
getting 50. 
But oxygen is terrible stuff if 

1295
01:14:22,040 --> 01:14:24,920
you're an Organism that evolved 
in an oxygen free world. 

1296
01:14:25,520 --> 01:14:28,640
The same reactivity that makes 
oxygen useful for energy 

1297
01:14:28,640 --> 01:14:31,080
production also makes it 
dangerous. 

1298
01:14:31,760 --> 01:14:35,600
Oxygen attacks organic 
molecules, breaking them down, 

1299
01:14:35,960 --> 01:14:39,560
causing what we'd now recognise 
as oxidative stress. 

1300
01:14:40,600 --> 01:14:43,280
To the microbes that had lived 
for billions of years in an 

1301
01:14:43,280 --> 01:14:46,520
oxygen free world, the 
appearance of oxygen in their 

1302
01:14:46,520 --> 01:14:49,680
environment was something 
between a catastrophe and an 

1303
01:14:49,680 --> 01:14:52,240
apocalypse. 
As oxygen producing 

1304
01:14:52,240 --> 01:14:56,080
cyanobacteria spread across the 
oceans, they began pumping 

1305
01:14:56,080 --> 01:15:00,560
oxygen into the water. 
Initially this oxygen reacted 

1306
01:15:00,560 --> 01:15:04,320
with dissolved iron, forming 
rust that precipitated out of 

1307
01:15:04,320 --> 01:15:07,000
the water and sank to the ocean 
floor. 

1308
01:15:08,040 --> 01:15:11,600
Today, we mine these ancient 
deposits as banded iron 

1309
01:15:11,600 --> 01:15:15,360
formations, alternating layers 
of iron oxide and other 

1310
01:15:15,360 --> 01:15:18,080
sediments that record the 
gradually increasing oxygen 

1311
01:15:18,080 --> 01:15:22,000
levels in Earth's oceans. 
They're basically fossil rust, 

1312
01:15:22,480 --> 01:15:25,080
and they represent one of the 
largest ore deposits on the 

1313
01:15:25,080 --> 01:15:27,440
planet. 
This process continued for 

1314
01:15:27,440 --> 01:15:31,720
hundreds of millions of years. 
The oceans accumulated oxygen 

1315
01:15:31,720 --> 01:15:35,280
while the atmosphere remained 
relatively oxygen free, because 

1316
01:15:35,280 --> 01:15:38,280
any oxygen that reached the 
atmosphere quickly reacted with 

1317
01:15:38,280 --> 01:15:42,080
methane and other gases. 
But eventually, around 2.4 

1318
01:15:42,080 --> 01:15:46,320
billion years ago, the sinks for
oxygen became saturated, the 

1319
01:15:46,320 --> 01:15:50,280
iron in the oceans had all 
rusted, the atmospheric methane 

1320
01:15:50,280 --> 01:15:54,000
had all oxidized, and oxygen 
began to accumulate in the 

1321
01:15:54,000 --> 01:15:56,760
atmosphere itself. 
This event, called the Great 

1322
01:15:56,760 --> 01:16:00,280
Oxidation Event, was possibly 
the most dramatic change in 

1323
01:16:00,280 --> 01:16:02,600
Earth's environment since the 
planet formed. 

1324
01:16:03,240 --> 01:16:06,000
It was also, from the 
perspective of most existing 

1325
01:16:06,000 --> 01:16:08,600
life forms, a mass extinction 
event. 

1326
01:16:09,240 --> 01:16:13,000
Organisms that couldn't tolerate
oxygen retreated to oxygen free 

1327
01:16:13,000 --> 01:16:18,160
environments, deep sediments, 
hydrothermal vents and the guts 

1328
01:16:18,160 --> 01:16:21,760
of other organisms. 
Many probably went extinct 

1329
01:16:21,760 --> 01:16:24,200
entirely. 
But the appearance of oxygen 

1330
01:16:24,200 --> 01:16:28,200
also created opportunities. 
Some organisms evolved ways to 

1331
01:16:28,200 --> 01:16:31,600
tolerate oxygen. 
A few even learnt to use it, 

1332
01:16:32,040 --> 01:16:35,320
developing aerobic metabolism 
that could extract far more 

1333
01:16:35,320 --> 01:16:38,480
energy from food molecules than 
their anaerobic cousins. 

1334
01:16:39,440 --> 01:16:43,000
These oxygen using organisms had
a significant advantage. 

1335
01:16:43,600 --> 01:16:46,960
More energy meant they could 
grow faster, reproduce more 

1336
01:16:46,960 --> 01:16:49,720
quickly and colonise more 
environments. 

1337
01:16:50,120 --> 01:16:53,040
The accumulation of oxygen had 
another profound effect. 

1338
01:16:53,560 --> 01:16:58,520
It created the ozone layer. 
Ozone O3 forms when ultraviolet 

1339
01:16:58,520 --> 01:17:00,960
radiation splits oxygen 
molecules. 

1340
01:17:01,320 --> 01:17:05,920
O2 and the resulting free oxygen
atoms combined with other oxygen

1341
01:17:05,920 --> 01:17:09,400
molecules, this ozone 
concentrated in the upper 

1342
01:17:09,400 --> 01:17:12,840
atmosphere, where it absorbed 
ultraviolet radiation that had 

1343
01:17:12,840 --> 01:17:14,560
previously reached Earth's 
surface. 

1344
01:17:15,200 --> 01:17:18,840
The ozone layer effectively gave
Earth a sunscreen, protecting 

1345
01:17:18,840 --> 01:17:21,960
surface dwelling organisms from 
the genetic damage caused by 

1346
01:17:21,960 --> 01:17:25,120
intense UV radiation. 
But then something strange 

1347
01:17:25,120 --> 01:17:28,840
happened. 
Around 2.4 billion years ago, 

1348
01:17:29,200 --> 01:17:32,360
shortly after oxygen began 
accumulating in the atmosphere, 

1349
01:17:33,000 --> 01:17:36,160
Earth experienced what 
geologists call the Huronian 

1350
01:17:36,160 --> 01:17:42,320
glaciation, the 1st and possibly
longest of several snowball 

1351
01:17:42,400 --> 01:17:45,440
Earth events. 
For hundreds of millions of 

1352
01:17:45,440 --> 01:17:48,680
years, ice may have covered most
or all of Earth's surface from 

1353
01:17:48,680 --> 01:17:51,520
pole to pole, extending even to 
the equator. 

1354
01:17:51,880 --> 01:17:54,560
How does a planet that had been 
warm enough for liquid ocean 

1355
01:17:54,560 --> 01:17:57,800
suddenly freeze solid? 
The culprit was probably the 

1356
01:17:57,800 --> 01:18:01,760
Great Oxidation Event itself. 
Remember all that methane in the

1357
01:18:01,760 --> 01:18:04,640
atmosphere? 
Methane is a powerful greenhouse

1358
01:18:04,640 --> 01:18:07,440
gas. 
When oxygen reacted with and 

1359
01:18:07,440 --> 01:18:10,840
removed atmospheric methane, it 
dramatically reduced the 

1360
01:18:10,840 --> 01:18:14,160
greenhouse effect. 
Without methane trapping heat, 

1361
01:18:14,520 --> 01:18:17,800
Earth's temperature plummeted. 
The transition to an ice covered

1362
01:18:17,800 --> 01:18:20,880
world probably happened 
gradually, but it was driven by 

1363
01:18:20,880 --> 01:18:22,760
a powerful positive feedback 
loop. 

1364
01:18:23,840 --> 01:18:27,600
As ice and snow covered more of 
Earth's surface, they reflected 

1365
01:18:27,600 --> 01:18:31,680
more sunlight back into space. 
This cooling lead to more ice 

1366
01:18:31,680 --> 01:18:35,320
formation, which reflected more 
sunlight, leading to more 

1367
01:18:35,320 --> 01:18:38,360
cooling, and so on. 
Eventually, Earth may have 

1368
01:18:38,360 --> 01:18:43,080
become completely frozen, a 
giant cosmic snowball orbiting 

1369
01:18:43,080 --> 01:18:45,440
the sun. 
You might reasonably ask how 

1370
01:18:45,440 --> 01:18:48,440
life survived this deep freeze. 
The answer involves a 

1371
01:18:48,440 --> 01:18:52,120
combination of refudes and 
remarkable microbial resilience.

1372
01:18:52,640 --> 01:18:56,600
Life probably persisted near 
hydrothermal vents, in volcanic 

1373
01:18:56,600 --> 01:18:59,960
Hot Springs, and possibly in 
pockets of liquid water. 

1374
01:18:59,960 --> 01:19:03,200
Under the ice. 
Microbes can survive remarkably 

1375
01:19:03,200 --> 01:19:06,880
hostile conditions when they 
need to, entering dormant States

1376
01:19:06,880 --> 01:19:09,320
and waiting out unfavourable 
periods. 

1377
01:19:09,640 --> 01:19:12,080
The end of Snowball Earth 
required another feedback 

1378
01:19:12,080 --> 01:19:15,480
mechanism. 
Volcanic activity continued even

1379
01:19:15,480 --> 01:19:18,960
under the ice, steadily pumping 
carbon dioxide into the 

1380
01:19:18,960 --> 01:19:21,840
atmosphere. 
Normally, this CO2 would be 

1381
01:19:21,840 --> 01:19:26,040
removed by weathering of rocks 
and dissolved in the oceans, but

1382
01:19:26,040 --> 01:19:29,360
with Earth's surface frozen, 
these processes essentially 

1383
01:19:29,360 --> 01:19:33,040
stopped. 
CO2 accumulated for millions of 

1384
01:19:33,040 --> 01:19:35,760
years until the greenhouse 
effect became strong enough to 

1385
01:19:35,760 --> 01:19:39,280
begin melting the ice. 
Once melting started, the same 

1386
01:19:39,280 --> 01:19:41,920
feedback loop that had frozen 
the planet now worked in 

1387
01:19:41,920 --> 01:19:44,880
reverse. 
Less ice meant less reflection 

1388
01:19:44,880 --> 01:19:47,880
of sunlight, which meant 
warming, which meant more 

1389
01:19:47,880 --> 01:19:52,400
melting, and so on. 
The transition from Snowball 

1390
01:19:52,400 --> 01:19:55,000
Earth to greenhouse conditions 
might have been relatively 

1391
01:19:55,000 --> 01:19:59,000
rapid, perhaps only a few 1000 
years, which is the blink of an 

1392
01:19:59,000 --> 01:20:02,600
eye in geological terms. 
When the ice melted, it revealed

1393
01:20:02,600 --> 01:20:05,800
a planet transformed. 
The long freeze had been a 

1394
01:20:05,800 --> 01:20:09,680
severe test, and many lineages 
probably didn't survive, but 

1395
01:20:09,680 --> 01:20:12,840
those that did emerged into a 
world with new possibilities. 

1396
01:20:13,480 --> 01:20:16,960
The stage was being set for the 
next great evolutionary 

1397
01:20:16,960 --> 01:20:21,560
innovation, the complex cell. 
For more than 2 billion years 

1398
01:20:21,560 --> 01:20:24,400
afterlife first appeared, Earth 
remained a planet of 

1399
01:20:24,400 --> 01:20:27,400
prokaryotes. 
Simple cells without internal 

1400
01:20:27,400 --> 01:20:30,400
membrane bound structures. 
These cells accomplished 

1401
01:20:30,400 --> 01:20:34,560
remarkable things, developing 
photosynthesis, nitrogen 

1402
01:20:34,560 --> 01:20:38,840
fixation, and various forms of 
metabolism, but they remained 

1403
01:20:38,840 --> 01:20:41,000
fundamentally simple in their 
architecture. 

1404
01:20:41,360 --> 01:20:44,520
Then, somewhere around 2 billion
years ago, something 

1405
01:20:44,520 --> 01:20:48,240
unprecedented happened. 
A larger prokaryote engulfed a 

1406
01:20:48,240 --> 01:20:52,560
smaller one, perhaps intending 
to digest it for food, but 

1407
01:20:52,560 --> 01:20:55,840
instead of being digested, the 
smaller cell survived inside the

1408
01:20:55,840 --> 01:20:58,280
larger one. 
The two cells began A 

1409
01:20:58,280 --> 01:21:00,520
partnership that would transform
life on Earth. 

1410
01:21:00,960 --> 01:21:04,920
This process, called 
endosymbiosis, created the first

1411
01:21:04,920 --> 01:21:09,080
eukaryotic cells, cells with a 
nucleus and other membrane bound

1412
01:21:09,080 --> 01:21:12,120
organelles. 
The engulfed cell became the 

1413
01:21:12,120 --> 01:21:16,880
mitochondrion, the powerhouse of
the cell responsible for aerobic

1414
01:21:16,880 --> 01:21:19,480
respiration. 
This partnership was 

1415
01:21:19,480 --> 01:21:22,840
spectacularly successful because
it combined the larger cells 

1416
01:21:22,840 --> 01:21:26,040
ability to move and acquire 
resources with the smaller cells

1417
01:21:26,040 --> 01:21:28,880
efficient oxygen based 
metabolism. 

1418
01:21:29,240 --> 01:21:32,040
Later, some of these early 
eukaryotes engulfed 

1419
01:21:32,040 --> 01:21:36,240
photosynthetic cyanobacteria 
which became chloroplasts. 

1420
01:21:36,880 --> 01:21:40,240
This second endosymbiotic event 
created the first algae and 

1421
01:21:40,480 --> 01:21:43,600
eventually led to all 
photosynthetic eukaryotes, 

1422
01:21:44,000 --> 01:21:47,080
including the plants that would 
eventually colonise land. 

1423
01:21:47,560 --> 01:21:50,560
The eukaryotic cell was like 
upgrading from a studio 

1424
01:21:50,560 --> 01:21:53,880
apartment to a mansion with 
multiple specialised rooms. 

1425
01:21:54,440 --> 01:21:56,640
Mitochondria handled energy 
production. 

1426
01:21:57,040 --> 01:22:00,160
The nucleus protected genetic 
material and controlled gene 

1427
01:22:00,160 --> 01:22:02,880
expression. 
Various other organelles 

1428
01:22:02,880 --> 01:22:06,720
specialised in protein 
synthesis, waste processing and 

1429
01:22:06,720 --> 01:22:09,840
other functions. 
This specialisation allowed 

1430
01:22:09,840 --> 01:22:13,240
eukaryotes to become much more 
complex than their prokaryotic 

1431
01:22:13,240 --> 01:22:16,120
ancestors. 
With this new complexity came 

1432
01:22:16,120 --> 01:22:19,320
new possibilities. 
Eukaryotic cells could be 

1433
01:22:19,320 --> 01:22:23,080
larger, sometimes much larger, 
than prokaryotes. 

1434
01:22:23,560 --> 01:22:26,200
They could develop new 
structures and capabilities. 

1435
01:22:26,720 --> 01:22:29,400
And, crucially, they could 
eventually do something 

1436
01:22:29,400 --> 01:22:32,440
prokaryotes couldn't. 
They could aggregate into 

1437
01:22:32,440 --> 01:22:35,920
multicellular organisms, where 
different cells specialised in 

1438
01:22:35,920 --> 01:22:38,680
different functions. 
The first multicellular 

1439
01:22:38,680 --> 01:22:42,560
eukaryotes probably appeared 
around 1.5 to 2 billion years 

1440
01:22:42,560 --> 01:22:45,240
ago, though the exact timing is 
debated. 

1441
01:22:45,880 --> 01:22:49,040
These early multicellular forms 
were simple, perhaps just 

1442
01:22:49,040 --> 01:22:52,280
clusters of similar cells that 
offered advantages like increase

1443
01:22:52,280 --> 01:22:55,000
size and some protection from 
predators. 

1444
01:22:55,560 --> 01:22:58,880
But they represented a new 
strategy for life, one that 

1445
01:22:58,880 --> 01:23:02,440
would eventually lead to all the
complex organisms we see today. 

1446
01:23:02,840 --> 01:23:06,480
For a long time, possibly a 
billion years or more, these 

1447
01:23:06,480 --> 01:23:10,000
early multicellular organisms 
remained relatively simple. 

1448
01:23:10,720 --> 01:23:13,920
Life during this era, sometimes 
called the boring billion, 

1449
01:23:14,320 --> 01:23:16,320
proceeded without dramatic 
changes. 

1450
01:23:16,840 --> 01:23:20,000
Stromatolites still dominated 
coastal environments. 

1451
01:23:20,360 --> 01:23:23,160
The oceans contained various 
prokaryotes and simple 

1452
01:23:23,160 --> 01:23:26,960
eukaryotes. 
Life existed, evolved, and 

1453
01:23:26,960 --> 01:23:30,280
diversified, but nothing 
particularly revolutionary was 

1454
01:23:30,280 --> 01:23:35,360
happening. 
Then, around 720 to 635,000,000 

1455
01:23:35,360 --> 01:23:39,280
years ago, Earth experienced 
another series of Snowball Earth

1456
01:23:39,280 --> 01:23:43,000
events, the Sturtean and 
Marineoan glaciations. 

1457
01:23:43,600 --> 01:23:47,320
Once again, ice may have covered
most or all of the planet's 

1458
01:23:47,320 --> 01:23:50,280
surface. 
These freezes were severe enough

1459
01:23:50,280 --> 01:23:53,760
that geologists find evidence of
glacial deposits at tropical 

1460
01:23:53,760 --> 01:23:57,840
latitudes, suggesting ice 
existed even at the equator. 

1461
01:23:58,200 --> 01:24:01,200
These dramatic climate swings 
may have driven evolutionary 

1462
01:24:01,200 --> 01:24:04,240
innovation by creating extreme 
selective pressure. 

1463
01:24:04,920 --> 01:24:08,320
Organisms that could survive 
rapid environmental changes, 

1464
01:24:08,640 --> 01:24:12,120
that had flexible metabolisms, 
or that could enter dormant 

1465
01:24:12,120 --> 01:24:16,920
states had better survival odds.
When the ice finally melted, as 

1466
01:24:16,920 --> 01:24:20,600
it always did thanks to the 
build up of volcanic CO2, life 

1467
01:24:20,600 --> 01:24:23,280
rebounded into a world of new 
opportunities. 

1468
01:24:23,640 --> 01:24:26,800
And then, almost immediately 
after the last Snowball Earth 

1469
01:24:26,800 --> 01:24:30,360
event, something remarkable 
appeared in the fossil record. 

1470
01:24:30,920 --> 01:24:35,400
The Ediacran biota. 
Named after the Ediacra Hills in

1471
01:24:35,400 --> 01:24:39,240
Australia where they were first 
discovered, these organisms were

1472
01:24:39,240 --> 01:24:43,320
Earth's first large, complex, 
multicellular creatures. 

1473
01:24:43,720 --> 01:24:46,920
The Ediacran organisms were 
strange by modern standards. 

1474
01:24:47,400 --> 01:24:51,120
Many resembled quilted air 
mattresses with bodies divided 

1475
01:24:51,120 --> 01:24:55,120
into repeated segments. 
Some look like fronds, others 

1476
01:24:55,120 --> 01:24:58,560
like discs, and still others 
like 3 sided frisbees. 

1477
01:24:59,440 --> 01:25:03,560
Most were soft bodied, lacking 
the hard shells or skeletons 

1478
01:25:03,560 --> 01:25:07,080
that would become common later. 
They lived on or in the sea 

1479
01:25:07,080 --> 01:25:09,800
floor, possibly feeding by 
absorbing nutrients from the 

1480
01:25:09,800 --> 01:25:13,360
water or perhaps hosting 
photosynthetic symbionts. 

1481
01:25:13,760 --> 01:25:16,960
For about 40 million years, 
these odd creatures dominated 

1482
01:25:16,960 --> 01:25:20,440
the sea floor, representing 
Earth's first experiment with 

1483
01:25:20,440 --> 01:25:24,840
large, complex body forms. 
They ranged in size from a few 

1484
01:25:24,840 --> 01:25:29,120
centimetres to over a meter in 
length, absolutely enormous 

1485
01:25:29,120 --> 01:25:32,400
compared to anything that had 
existed before then. 

1486
01:25:32,720 --> 01:25:37,240
Around 541 million years ago, 
most Ediacron organisms 

1487
01:25:37,240 --> 01:25:39,000
disappeared from the fossil 
record. 

1488
01:25:39,880 --> 01:25:43,240
What caused their decline? 
The answer may be related to the

1489
01:25:43,240 --> 01:25:46,440
next great revolution in the 
history of life, the Cambrian 

1490
01:25:46,440 --> 01:25:49,200
explosion. 
If you could take a time machine

1491
01:25:49,200 --> 01:25:53,600
back to the early Cambrian 
period, about 541 million years 

1492
01:25:53,600 --> 01:25:57,960
ago, and put on a diving suit to
explore the sea floor, you'd 

1493
01:25:57,960 --> 01:26:00,520
witness one of the most 
spectacular displays of 

1494
01:26:00,560 --> 01:26:02,840
evolutionary innovation in 
Earth's history. 

1495
01:26:03,760 --> 01:26:08,200
Within a relatively brief 
period, perhaps 20 to 25,000,000

1496
01:26:08,200 --> 01:26:11,960
years, which is briefed by 
geological standards, life 

1497
01:26:11,960 --> 01:26:16,480
exploded into a bewildering 
array of new forms, many of them

1498
01:26:16,480 --> 01:26:19,720
completely unlike anything that 
had existed before. 

1499
01:26:20,080 --> 01:26:23,560
This was the Cambrian explosion,
and it marked the appearance of 

1500
01:26:23,560 --> 01:26:26,400
almost all the major animal 
phyla we see today. 

1501
01:26:27,080 --> 01:26:32,040
Arthropods, mollusks, 
echinoderms, cordates and worms 

1502
01:26:32,040 --> 01:26:35,160
of various sorts all appeared in
the Cambrian seas within a 

1503
01:26:35,160 --> 01:26:38,440
relatively short time window. 
It was as if life had been 

1504
01:26:38,440 --> 01:26:42,280
experimenting for billions of 
years and suddenly decided to 

1505
01:26:42,280 --> 01:26:44,960
try every possible body plan all
at once. 

1506
01:26:45,280 --> 01:26:47,760
What triggered this explosion of
diversity? 

1507
01:26:48,360 --> 01:26:51,000
The answer probably involves 
multiple factors coming 

1508
01:26:51,000 --> 01:26:53,680
together. 
Oxygen levels had risen to the 

1509
01:26:53,680 --> 01:26:56,640
point where active mobile 
animals could be supported. 

1510
01:26:57,280 --> 01:27:00,480
The evolution of predation 
created an evolutionary arms 

1511
01:27:00,480 --> 01:27:04,200
race where prey animals evolved 
defences and predators evolved 

1512
01:27:04,200 --> 01:27:09,000
ways to overcome those defences.
The development of hard parts, 

1513
01:27:09,240 --> 01:27:15,320
shells, spines, teeth provided 
both protection and new tools, 

1514
01:27:15,680 --> 01:27:19,240
while also making animals much 
more likely to fossilize, giving

1515
01:27:19,240 --> 01:27:22,800
us a better fossil record. 
The Cambrian seas were dominated

1516
01:27:22,800 --> 01:27:25,560
by arthropods, particularly 
trilobites. 

1517
01:27:26,320 --> 01:27:29,400
These creatures, distant 
relatives of modern insects and 

1518
01:27:29,400 --> 01:27:34,200
crustaceans, had segmented 
bodies, jointed legs, and hard 

1519
01:27:34,200 --> 01:27:37,160
exoskeletons. 
They could walk along the sea 

1520
01:27:37,160 --> 01:27:40,960
floor, swim in the water column 
and filter, feed or hunt for 

1521
01:27:40,960 --> 01:27:44,760
food. 
Trilobites were spectacularly 

1522
01:27:44,760 --> 01:27:48,480
successful, diversifying into 
thousands of species that 

1523
01:27:48,480 --> 01:27:51,000
occupied almost every marine 
environment. 

1524
01:27:51,360 --> 01:27:54,640
But the Cambrian seas also 
hosted stranger creatures. 

1525
01:27:55,240 --> 01:27:59,760
Anomalacaris, whose name means 
abnormal shrimp, was one of the 

1526
01:27:59,760 --> 01:28:03,760
Cambrian's top predators, with 
grasping appendages for catching

1527
01:28:03,760 --> 01:28:06,840
prey and a circular mouth lined 
with plates. 

1528
01:28:07,600 --> 01:28:11,840
Upper Binia had Five Eyes and 
proboscis with a grasping tip 

1529
01:28:11,840 --> 01:28:13,960
that it used to catch smaller 
animals. 

1530
01:28:14,680 --> 01:28:17,600
Hallucigenia was so bizarre when
first discovered that 

1531
01:28:17,600 --> 01:28:21,000
palaeontologists couldn't tell 
which end was the head or which 

1532
01:28:21,000 --> 01:28:24,120
side was up. 
It had spines on one side and 

1533
01:28:24,120 --> 01:28:27,000
legs on the other. 
These weird Cambrian creatures 

1534
01:28:27,000 --> 01:28:29,880
lived in a world that was alien 
by modern standards. 

1535
01:28:30,440 --> 01:28:34,200
The continents were barren rock.
Not a single plant or animal 

1536
01:28:34,200 --> 01:28:38,160
lived on land, yet the oceans 
were rich with life but 

1537
01:28:38,160 --> 01:28:41,640
different from today's oceans. 
There were no fish yet, no 

1538
01:28:41,640 --> 01:28:45,360
sharks, no whales. 
The largest predators were 

1539
01:28:45,360 --> 01:28:48,160
arthropods and odd creatures 
like a nomalocharis. 

1540
01:28:48,600 --> 01:28:51,480
But among the many strange 
creatures of the Cambrian, one 

1541
01:28:51,480 --> 01:28:54,760
group would prove particularly 
significant, the cordates, 

1542
01:28:55,080 --> 01:28:59,480
animals with a stiffening rod 
notochord running down their 

1543
01:28:59,480 --> 01:29:02,840
backs. 
Early cordates like Picaya and I

1544
01:29:02,840 --> 01:29:06,760
quiched this were small fish 
like creatures that swam through

1545
01:29:06,760 --> 01:29:10,000
the Cambrian seas. 
They weren't impressive compared

1546
01:29:10,000 --> 01:29:13,920
to the armoured trilobites or 
the grasping anomalacaridids. 

1547
01:29:14,560 --> 01:29:18,000
Yet they carried within their 
body plan the basic architecture

1548
01:29:18,000 --> 01:29:22,120
that would eventually give rise 
to fish, amphibians, reptiles, 

1549
01:29:22,120 --> 01:29:24,840
birds, mammals and eventually 
you. 

1550
01:29:25,400 --> 01:29:28,400
The Cambrian period established 
patterns that would shape life 

1551
01:29:28,400 --> 01:29:32,400
for the next half billion years.
Predator prey relationships 

1552
01:29:32,400 --> 01:29:36,160
drove evolutionary innovation. 
Hard parts became the norm, 

1553
01:29:36,480 --> 01:29:38,280
providing protection and 
structure. 

1554
01:29:39,480 --> 01:29:43,560
Animals developed increasingly 
sophisticated sensory systems. 

1555
01:29:44,040 --> 01:29:47,560
Eyes became common, allowing 
creatures to see their prey or 

1556
01:29:47,560 --> 01:29:52,040
spot predators from a distance. 
The basic body plans of modern 

1557
01:29:52,040 --> 01:29:55,280
animals were established, 
creating templates that would be

1558
01:29:55,280 --> 01:29:58,160
modified and adapted for 
countless different 

1559
01:29:58,160 --> 01:30:00,800
environments. 
As the Cambrian gave way to the 

1560
01:30:00,800 --> 01:30:05,120
All Division period around 485 
million years ago, life 

1561
01:30:05,120 --> 01:30:09,240
continued to diversify. 
The first true fish appeared 

1562
01:30:09,680 --> 01:30:13,160
jawless creatures that filtered 
food from the water or scraped 

1563
01:30:13,160 --> 01:30:17,040
it off rocks. 
Cephalopods, relatives of modern

1564
01:30:17,040 --> 01:30:21,280
squid and octopuses, evolved 
into efficient predators, some 

1565
01:30:21,280 --> 01:30:25,240
with straight shells. 
Meters long reefs built by 

1566
01:30:25,240 --> 01:30:29,240
various organisms began to 
dominate shallow seas, creating 

1567
01:30:29,240 --> 01:30:32,480
complex habitats that supported 
diverse communities. 

1568
01:30:32,800 --> 01:30:34,840
But life remained entirely 
aquatic. 

1569
01:30:35,480 --> 01:30:38,680
The land was still barren, 
waiting for the organisms that 

1570
01:30:38,680 --> 01:30:42,960
would eventually colonise it. 
That transition was coming, but 

1571
01:30:42,960 --> 01:30:46,000
it would require some of the 
most dramatic adaptations in the

1572
01:30:46,000 --> 01:30:49,240
history of life. 
Stand on a Silurian seashore 

1573
01:30:49,240 --> 01:30:53,280
around 440 million years ago and
you'd see a stark contrast 

1574
01:30:53,280 --> 01:30:57,080
between 2 worlds. 
Behind you, The ocean teamed 

1575
01:30:57,080 --> 01:31:02,440
with life, fish, arthropods, 
mollusks and a chinoderms all 

1576
01:31:02,440 --> 01:31:05,640
going about their business in 
the water before you stretched 

1577
01:31:05,640 --> 01:31:09,360
the land. 
Rocky, barren, lifeless, the 

1578
01:31:09,360 --> 01:31:12,880
most advanced terrestrial 
ecosystem consisted of microbial

1579
01:31:12,880 --> 01:31:16,480
mats in wet areas and possibly 
some lichens beginning to 

1580
01:31:16,480 --> 01:31:20,320
colonise the rocks. 
There were no trees, no grass, 

1581
01:31:20,640 --> 01:31:25,480
no flowers, no insects, no birds
and no mammals. 

1582
01:31:25,880 --> 01:31:27,880
Just bare rock weathering under 
the sun. 

1583
01:31:28,240 --> 01:31:31,200
But in the shallow waters and 
tidal zones, something 

1584
01:31:31,200 --> 01:31:34,920
revolutionary was beginning. 
Plants descended from green 

1585
01:31:34,920 --> 01:31:37,600
algae were starting to venture 
onto land. 

1586
01:31:38,320 --> 01:31:41,480
This wasn't a sudden conquest, 
but a gradual process that 

1587
01:31:41,480 --> 01:31:46,400
probably took millions of years.
The first land plants were tiny,

1588
01:31:46,880 --> 01:31:50,360
perhaps only a few centimetres 
tall, and they required very 

1589
01:31:50,360 --> 01:31:54,400
moist conditions. 
They had no true roots, leaves 

1590
01:31:54,400 --> 01:31:58,640
or stems as we'd recognise them 
today, just simple structures 

1591
01:31:58,640 --> 01:32:02,400
that barely qualified as plants.
The challenge of living on land 

1592
01:32:02,400 --> 01:32:05,680
was immense. 
In the water, organisms are 

1593
01:32:05,680 --> 01:32:09,480
supported by buoyancy, 
surrounded by moisture and 

1594
01:32:09,480 --> 01:32:11,640
protected from temperature 
extremes. 

1595
01:32:12,280 --> 01:32:16,600
On land, gravity pulls harder, 
the air is dry, temperatures 

1596
01:32:16,600 --> 01:32:20,680
fluctuate wildly and UV 
radiation is more intense. 

1597
01:32:21,320 --> 01:32:24,560
To survive on land, organisms 
needed to solve all these 

1598
01:32:24,560 --> 01:32:27,840
problems simultaneously. 
Early land plants developed 

1599
01:32:27,840 --> 01:32:31,600
several crucial innovations. 
They evolved a waxy coating 

1600
01:32:31,600 --> 01:32:33,800
called a cuticle to prevent 
water loss. 

1601
01:32:34,480 --> 01:32:37,920
They developed simple conducting
tissues to transport water from 

1602
01:32:37,920 --> 01:32:39,800
the ground to their growing 
tips. 

1603
01:32:40,440 --> 01:32:43,600
They formed associations with 
fungi that help them extract 

1604
01:32:43,600 --> 01:32:46,920
nutrients from the thin soils 
developing on weathered rock. 

1605
01:32:47,840 --> 01:32:51,760
These plant fungal partnerships,
called mycorrhizye, were so 

1606
01:32:51,760 --> 01:32:55,360
successful that they persist in 
most modern plants today. 

1607
01:32:55,800 --> 01:33:00,760
By the Devonian period, around 
420 million years ago, land 

1608
01:33:00,760 --> 01:33:02,760
plants had diversified 
dramatically. 

1609
01:33:03,240 --> 01:33:06,360
Some developed true roots that 
could penetrate deeper into the 

1610
01:33:06,360 --> 01:33:09,880
soil, anchoring larger plants 
and accessing more water. 

1611
01:33:10,800 --> 01:33:15,240
Others evolved vascular tissue, 
specialised cells for conducting

1612
01:33:15,240 --> 01:33:18,320
water and nutrients that allowed
them to grow taller. 

1613
01:33:19,320 --> 01:33:23,120
The race for sunlight had begun,
and plants responded by reaching

1614
01:33:23,120 --> 01:33:25,360
upward. 
The first forests appeared 

1615
01:33:25,360 --> 01:33:28,120
during the Middle Devonian, 
though they would have looked 

1616
01:33:28,120 --> 01:33:31,560
alien to modern eyes. 
They were dominated by tree 

1617
01:33:31,560 --> 01:33:36,160
size, club mosses, horse tails, 
and ferns, groups that today are

1618
01:33:36,160 --> 01:33:39,400
mostly small plants. 
These early trees could reach 

1619
01:33:39,400 --> 01:33:43,000
heights of over 30 meters, 
creating the first complex 

1620
01:33:43,000 --> 01:33:46,640
terrestrial ecosystems. 
Their roots broke up rock, 

1621
01:33:46,920 --> 01:33:49,520
accelerating weathering and soil
formation. 

1622
01:33:50,320 --> 01:33:53,520
When they died and fell, they 
created habitats for other 

1623
01:33:53,520 --> 01:33:55,960
organisms. 
Life was transforming the 

1624
01:33:55,960 --> 01:33:59,360
landscape, but plants didn't 
colonize land alone. 

1625
01:33:59,680 --> 01:34:02,640
They were followed or perhaps 
accompanied by animals. 

1626
01:34:03,480 --> 01:34:06,400
The first terrestrial animals 
were probably arthropods, 

1627
01:34:06,680 --> 01:34:10,440
millipedes, and centipedes, and 
possibly early arachnids. 

1628
01:34:11,160 --> 01:34:14,440
These creatures likely began as 
coastal or semi aquatic 

1629
01:34:14,440 --> 01:34:17,520
organisms that gradually adapted
to terrestrial life. 

1630
01:34:18,240 --> 01:34:22,040
They had advantages for land 
living, their exoskeletons 

1631
01:34:22,040 --> 01:34:25,720
provided structural support and 
protection from drying, and 

1632
01:34:25,720 --> 01:34:28,480
their jointed legs worked well 
for walking on irregular 

1633
01:34:28,480 --> 01:34:31,120
surfaces. 
By the late Devonian, around 

1634
01:34:31,120 --> 01:34:35,680
375,000,000 years ago, insects 
had appeared and were beginning 

1635
01:34:35,680 --> 01:34:39,520
to diversify. 
Some evolved wings, becoming the

1636
01:34:39,520 --> 01:34:42,040
first animals capable of powered
flight. 

1637
01:34:42,640 --> 01:34:46,000
This innovation opened new 
dimensions of terrestrial space,

1638
01:34:46,400 --> 01:34:50,480
allowing insects to disperse 
widely, escape predators and 

1639
01:34:50,720 --> 01:34:54,760
eventually pollinate plants. 
But the most dramatic transition

1640
01:34:54,760 --> 01:34:58,320
to land was being made by a 
group of fish in the shallow 

1641
01:34:58,320 --> 01:35:00,440
waters and swamps of the 
Devonian. 

1642
01:35:00,840 --> 01:35:05,200
Some fish had evolved muscular 
lobed fins that could support 

1643
01:35:05,200 --> 01:35:08,440
their weight and lungs that 
could extract oxygen from air. 

1644
01:35:09,080 --> 01:35:12,240
These lobe finned fish could 
haul themselves out of the water

1645
01:35:12,240 --> 01:35:15,680
and move across land, possibly 
to reach new water bodies or 

1646
01:35:15,680 --> 01:35:18,520
escape predators. 
Creatures like Tiktaalik 

1647
01:35:18,520 --> 01:35:21,120
represented an intermediate 
stage between fish and 

1648
01:35:21,120 --> 01:35:25,840
tetrapods, 4 legged vertebrates.
They had fins with bones that 

1649
01:35:25,840 --> 01:35:28,440
corresponded to our upper arm, 
forearm, and something 

1650
01:35:28,440 --> 01:35:32,000
resembling a wrist. 
They had lungs and gills, a 

1651
01:35:32,000 --> 01:35:34,600
Flathead that could support the 
weight when out of water, and a 

1652
01:35:34,600 --> 01:35:38,040
flexible neck. 
Tiktaalik could do push ups with

1653
01:35:38,040 --> 01:35:41,600
its front fins, lifting its head
above water to breathe air or 

1654
01:35:41,600 --> 01:35:44,280
look around. 
Over millions of years, these 

1655
01:35:44,280 --> 01:35:48,200
fish like creatures gave rise to
true tetrapods, animals with 

1656
01:35:48,200 --> 01:35:52,000
four limbs rather than fins. 
Early tetrapods like a 

1657
01:35:52,000 --> 01:35:55,440
Canthostiga still spent most of 
their time in water, but they 

1658
01:35:55,440 --> 01:35:59,360
had digits, fingers and toes 
rather than fin rays. 

1659
01:36:00,000 --> 01:36:02,760
They represented A commitment to
the new lifestyle that land 

1660
01:36:02,760 --> 01:36:05,600
offered, even though they 
weren't yet fully terrestrial. 

1661
01:36:05,920 --> 01:36:10,040
By the Carboniferous period, 
around 350 million years ago, 

1662
01:36:10,040 --> 01:36:12,520
tetrapods had fully transitioned
to land. 

1663
01:36:13,320 --> 01:36:17,280
Amphibians diversified into 
numerous forms, from small 

1664
01:36:17,280 --> 01:36:19,640
salamander like creatures to 
massive beasts. 

1665
01:36:19,640 --> 01:36:24,040
Several metres long, these early
amphibians still required water 

1666
01:36:24,040 --> 01:36:26,880
for reproduction. 
Their eggs had no shell and 

1667
01:36:26,880 --> 01:36:30,280
would dry out in air, but they 
could live entirely on land as 

1668
01:36:30,280 --> 01:36:32,520
adults. 
The Carboniferous world would 

1669
01:36:32,520 --> 01:36:34,280
have been a strange place to 
visit. 

1670
01:36:34,960 --> 01:36:38,560
The forests were dominated by 
enormous club mosses and horse 

1671
01:36:38,560 --> 01:36:42,000
tails, creating swampy 
environments where dead plant 

1672
01:36:42,000 --> 01:36:44,720
material accumulated faster than
it could decay. 

1673
01:36:45,640 --> 01:36:47,960
This plant material would 
eventually become the coal 

1674
01:36:47,960 --> 01:36:51,120
deposits that gave the 
Carboniferous its name and 

1675
01:36:51,120 --> 01:36:52,920
powered the Industrial 
Revolution. 

1676
01:36:52,920 --> 01:36:56,720
Hundreds of millions of years 
later, insects thrived in these 

1677
01:36:56,720 --> 01:36:59,960
forests, growing to sizes that 
seem impossible today. 

1678
01:37:00,680 --> 01:37:05,080
Dragonflies with wingspans of 70
centimetres, about the size of a

1679
01:37:05,080 --> 01:37:08,880
hawk, haunted smaller insects 
through the forest canopy. 

1680
01:37:09,440 --> 01:37:12,880
Millipedes over 2 metres long 
crawled through the leaf litter.

1681
01:37:13,640 --> 01:37:16,640
The high oxygen content of the 
Carboniferous atmosphere, 

1682
01:37:17,080 --> 01:37:22,120
perhaps 35% compared to today's 
21%, allowed these arthropods to

1683
01:37:22,120 --> 01:37:24,560
reach sizes that their 
respiratory systems couldn't 

1684
01:37:24,560 --> 01:37:27,600
support in today's atmosphere. 
But the most significant 

1685
01:37:27,640 --> 01:37:30,400
evolutionary innovation of this 
era was happening quietly 

1686
01:37:30,400 --> 01:37:34,080
amongst certain amphibians. 
Some lineages were developing 

1687
01:37:34,080 --> 01:37:37,760
eggs with shells, eggs that 
could be laid on land rather 

1688
01:37:37,760 --> 01:37:41,560
than in water. 
This amniotic egg, with its 

1689
01:37:41,560 --> 01:37:45,640
protective shell and internal 
membrane, freed vertebrates from

1690
01:37:45,640 --> 01:37:48,080
their dependence on water for 
reproduction. 

1691
01:37:48,800 --> 01:37:52,000
The animals that developed this 
innovation would give rise to 

1692
01:37:52,000 --> 01:37:56,320
all reptiles, birds and mammals.
As the Carboniferous gave way to

1693
01:37:56,320 --> 01:38:00,680
the Permian period around 299 
million years ago, Earth entered

1694
01:38:00,680 --> 01:38:03,840
a new phase. 
The continents, which had been 

1695
01:38:03,840 --> 01:38:06,400
scattered during earlier 
periods, were gradually 

1696
01:38:06,400 --> 01:38:09,320
colliding to form a 
supercontinent called Pangaea, 

1697
01:38:09,760 --> 01:38:14,520
Greek for all Earth. 
This massive landmass stretched 

1698
01:38:14,520 --> 01:38:17,960
from pole to pole, surrounded by
a single vast ocean called 

1699
01:38:17,960 --> 01:38:20,760
Panthelassa. 
The formation of Pangaea had 

1700
01:38:20,760 --> 01:38:22,920
profound effects on climate and 
life. 

1701
01:38:23,560 --> 01:38:26,760
With one giant continent, the 
interior regions were far from 

1702
01:38:26,760 --> 01:38:31,040
any ocean, creating extensive 
deserts with extreme temperature

1703
01:38:31,040 --> 01:38:33,800
ranges. 
Coastal regions experienced 

1704
01:38:33,800 --> 01:38:37,320
monsoon patterns with wet and 
dry seasons of unusual 

1705
01:38:37,320 --> 01:38:40,480
intensity. 
The climate overall was becoming

1706
01:38:40,480 --> 01:38:44,320
drier and more seasonal. 
Amniotes, animals with shelled 

1707
01:38:44,320 --> 01:38:47,080
eggs, diversified into two main 
groups. 

1708
01:38:47,960 --> 01:38:51,080
The synapsids, which would 
eventually give rise to mammals,

1709
01:38:51,400 --> 01:38:54,360
became the dominant large land 
animals of the Permian. 

1710
01:38:55,160 --> 01:38:59,920
Many were spectacular creatures.
Demetrodon, often mistakenly 

1711
01:38:59,920 --> 01:39:03,800
called a dinosaur, had a huge 
sail on its back that probably 

1712
01:39:03,800 --> 01:39:05,640
helped regulate its body 
temperature. 

1713
01:39:06,320 --> 01:39:08,880
Their apsids evolved 
increasingly mammal like 

1714
01:39:08,880 --> 01:39:12,480
features, including 
differentiated teeth, more 

1715
01:39:12,480 --> 01:39:15,800
efficient locomotion, and 
possibly even whiskers and body 

1716
01:39:15,800 --> 01:39:18,520
hair in some species. 
The other major group, the 

1717
01:39:18,520 --> 01:39:22,200
soropsids, included all modern 
reptiles and would eventually 

1718
01:39:22,200 --> 01:39:24,080
give rise to dinosaurs and 
birds. 

1719
01:39:24,840 --> 01:39:27,480
These creatures were exploring 
different solutions to the 

1720
01:39:27,480 --> 01:39:30,840
challenges of terrestrial life, 
particularly the problem of 

1721
01:39:30,840 --> 01:39:33,720
regulating body temperature 
without the constant presence of

1722
01:39:33,720 --> 01:39:37,880
water for cooling. 
But then 252,000,000 years ago, 

1723
01:39:38,320 --> 01:39:41,560
Earth experienced the most 
catastrophic extinction event in

1724
01:39:41,560 --> 01:39:45,920
its history, the Permian 
Triassic extinction, sometimes 

1725
01:39:45,920 --> 01:39:48,960
called the Great Dying. 
Over a period that might have 

1726
01:39:48,960 --> 01:39:52,200
lasted from 10s of thousands to 
hundreds of thousands of years, 

1727
01:39:52,560 --> 01:39:56,840
approximately 96% of all marine 
species and 70% of terrestrial 

1728
01:39:56,840 --> 01:40:00,240
vertebrate species went extinct.
The cause of this extinction is 

1729
01:40:00,240 --> 01:40:04,080
still debated, but the leading 
suspect is massive volcanic 

1730
01:40:04,080 --> 01:40:07,800
eruptions in Siberia that 
released enormous quantities of 

1731
01:40:07,800 --> 01:40:11,000
lava and gases. 
These eruptions created the 

1732
01:40:11,000 --> 01:40:15,400
Siberian Traps, vast fields of 
basalt that still cover much of 

1733
01:40:15,400 --> 01:40:18,880
Siberia today. 
The volcanic activity released 

1734
01:40:18,880 --> 01:40:22,280
carbon dioxide and other gases 
that warmed the planet 

1735
01:40:22,280 --> 01:40:25,760
dramatically. 
Ocean temperatures rose and the 

1736
01:40:25,760 --> 01:40:29,560
warmer water couldn't hold as 
much dissolved oxygen, creating 

1737
01:40:29,560 --> 01:40:34,240
vast dead zones. 
Acid rain fell on land and ocean

1738
01:40:34,240 --> 01:40:36,920
alike. 
It was a planetary disaster that

1739
01:40:36,920 --> 01:40:40,000
came closer than any other event
to wiping out complex life 

1740
01:40:40,000 --> 01:40:43,240
entirely. 
Yet life persisted in the 

1741
01:40:43,240 --> 01:40:45,120
aftermath of the Permian 
extinction. 

1742
01:40:45,440 --> 01:40:48,640
Surviving species rapidly 
diversified to fill the 

1743
01:40:48,640 --> 01:40:51,560
ecological roles left empty by 
the mass die off. 

1744
01:40:52,280 --> 01:40:55,360
The Triassic period that 
followed was a time of recovery 

1745
01:40:55,360 --> 01:40:58,640
and innovation when many modern 
groups first appeared. 

1746
01:40:59,000 --> 01:41:02,600
Among the survivors were the 
ancestors of dinosaurs, a group 

1747
01:41:02,600 --> 01:41:06,520
of archosaurs ruling reptiles 
that have been relatively minor 

1748
01:41:06,520 --> 01:41:10,760
players in Permian ecosystems. 
In the Triassic, these creatures

1749
01:41:10,760 --> 01:41:13,000
began to evolve some remarkable 
features. 

1750
01:41:13,600 --> 01:41:17,040
They developed an upright 
posture with legs directly under

1751
01:41:17,040 --> 01:41:19,560
their bodies, rather than 
sprawling to the sides like 

1752
01:41:19,560 --> 01:41:23,000
earlier reptiles. 
This more efficient locomotion 

1753
01:41:23,000 --> 01:41:26,040
allowed them to be more active 
and cover more ground with less 

1754
01:41:26,040 --> 01:41:28,680
energy. 
By the Late Triassic, the first 

1755
01:41:28,760 --> 01:41:33,080
true dinosaurs had appeared. 
Relatively small bipedal 

1756
01:41:33,080 --> 01:41:36,480
creatures that ran on their hind
legs, they weren't immediately 

1757
01:41:36,480 --> 01:41:39,000
dominant. 
They shared the landscape with 

1758
01:41:39,000 --> 01:41:43,200
various other reptiles, early 
crocodile relatives, and large 

1759
01:41:43,200 --> 01:41:46,520
amphibians, but they were 
successful enough to survive the

1760
01:41:46,520 --> 01:41:49,560
next catastrophe. 
At the end of the Triassic, 

1761
01:41:49,880 --> 01:41:54,000
around 201,000,000 years ago, 
another mass extinction event, 

1762
01:41:54,000 --> 01:41:58,080
probably caused by more massive 
volcanic eruptions, eliminated 

1763
01:41:58,080 --> 01:42:00,920
many of the groups that have 
been competing with dinosaurs. 

1764
01:42:01,960 --> 01:42:05,200
The dinosaurs survived and in 
the Jurassic period that 

1765
01:42:05,200 --> 01:42:09,080
followed exploded into 
remarkable diversity. 

1766
01:42:09,400 --> 01:42:13,560
The Jurassic and Cretaceous 
periods to and to 66,000,000 

1767
01:42:13,560 --> 01:42:17,040
years ago were the age of 
dinosaurs, when these creatures 

1768
01:42:17,040 --> 01:42:20,440
came to dominate terrestrial 
ecosystems in ways no group had 

1769
01:42:20,440 --> 01:42:24,960
before or has since. 
They ranged in size from chicken

1770
01:42:24,960 --> 01:42:28,400
size predators to the largest 
land animals that ever lived, 

1771
01:42:28,840 --> 01:42:32,320
sauropods like Argentinosaurus 
that may have weighed over 70 

1772
01:42:32,320 --> 01:42:35,200
tons, the equivalent of about 12
elephants. 

1773
01:42:35,520 --> 01:42:39,240
Dinosaurs evolved into every 
conceivable ecological role. 

1774
01:42:39,760 --> 01:42:42,440
There were predators like 
Allosaurus and Tyrannosaurus 

1775
01:42:42,440 --> 01:42:47,480
Rex, herbivores like Stegosaurus
and Triceratops, omnivores, 

1776
01:42:47,720 --> 01:42:52,160
insectivores, and possibly even 
some that fed primarily on fish 

1777
01:42:52,160 --> 01:42:56,160
or carrion. 
Some ran on 2 legs, others on 4.

1778
01:42:56,760 --> 01:43:00,360
Some were armoured with plates 
and spikes, others relied on 

1779
01:43:00,360 --> 01:43:04,680
speed or size for defence. 
Some were solitary, others lived

1780
01:43:04,680 --> 01:43:07,480
in herds. 
They adapted to environments 

1781
01:43:07,480 --> 01:43:10,360
ranging from polar forests to 
deserts to swamps. 

1782
01:43:10,720 --> 01:43:13,400
But dinosaurs weren't the only 
remarkable creatures of this 

1783
01:43:13,400 --> 01:43:16,120
era. 
In the Jurassic, one group of 

1784
01:43:16,120 --> 01:43:19,320
small, feathered dinosaurs 
evolved the ability to fly, 

1785
01:43:19,760 --> 01:43:23,680
giving rise to birds. 
The first birds, like 

1786
01:43:23,680 --> 01:43:27,440
Archaeopteryx, retained many 
dinosaur in features, teeth, 

1787
01:43:27,720 --> 01:43:32,640
Bony tails, clawed fingers, but 
they could fly, opening new 

1788
01:43:32,640 --> 01:43:36,080
ecological opportunities. 
In the oceans, reptiles had 

1789
01:43:36,080 --> 01:43:39,720
returned to aquatic life. 
Ichthyosaurs, shaped like 

1790
01:43:39,720 --> 01:43:43,040
dolphins, were fast swimming 
predators that gave birth to 

1791
01:43:43,040 --> 01:43:46,440
live young in the water. 
Plesiosaurs, with their long 

1792
01:43:46,440 --> 01:43:49,640
necks and flippers, haunted fish
and squid. 

1793
01:43:50,440 --> 01:43:54,080
Mosasaurs, which appeared in the
Cretaceous, grew to lengths of 

1794
01:43:54,080 --> 01:43:57,520
over 15 metres and were apex 
predators of the Seas. 

1795
01:43:57,800 --> 01:44:01,800
Meanwhile, mammals, descendants 
of those mammal like synapsids 

1796
01:44:01,800 --> 01:44:05,640
from the Permian, were present 
throughout the Mesozoic era but 

1797
01:44:05,640 --> 01:44:08,440
remained relatively small and 
mostly nocturnal. 

1798
01:44:09,200 --> 01:44:13,200
They had evolved fur, warm 
bloodedness and sophisticated 

1799
01:44:13,200 --> 01:44:16,880
teeth, but they couldn't compete
with dinosaurs for the dominant 

1800
01:44:16,920 --> 01:44:21,800
ecological roles. 
For over 150 million years, 

1801
01:44:21,800 --> 01:44:25,800
mammals remained in the shadows,
living in the margins of a world

1802
01:44:25,800 --> 01:44:28,800
ruled by reptiles. 
The flowering plants, 

1803
01:44:28,920 --> 01:44:33,200
angiosperms, appeared in the 
Cretaceous around 130,000,000 

1804
01:44:33,200 --> 01:44:36,280
years ago and quickly became the
dominant land plants. 

1805
01:44:36,920 --> 01:44:40,720
These plants had evolved flowers
and fruits, structures designed 

1806
01:44:40,720 --> 01:44:43,160
to attract pollinators and seed 
dispersers. 

1807
01:44:43,880 --> 01:44:46,800
The partnership between 
flowering plants and insects, 

1808
01:44:47,160 --> 01:44:50,640
and eventually birds and 
mammals, created new complexity 

1809
01:44:50,640 --> 01:44:55,240
and terrestrial ecosystems. 
Butterflies and bees evolved to 

1810
01:44:55,240 --> 01:44:59,480
pollinate specific flowers. 
Trees evolved fruits to entice 

1811
01:44:59,480 --> 01:45:04,000
animals to disperse their seeds.
By the late Cretaceous, Earth's 

1812
01:45:04,000 --> 01:45:07,240
ecosystems had reached a level 
of complexity comparable to 

1813
01:45:07,240 --> 01:45:10,240
today's. 
There were diverse forests, 

1814
01:45:10,280 --> 01:45:12,520
grasslands, wetlands and 
deserts. 

1815
01:45:13,240 --> 01:45:16,920
Food webs were intricate, with 
multiple trophic levels and 

1816
01:45:16,920 --> 01:45:19,240
specialised relationships 
between species. 

1817
01:45:19,960 --> 01:45:23,560
The planet was teeming with 
life, from microscopic plankton 

1818
01:45:23,560 --> 01:45:27,840
to enormous dinosaurs, from 
flowering plants to social 

1819
01:45:27,840 --> 01:45:31,200
insects. 
And then, 66,000,000 years ago, 

1820
01:45:31,200 --> 01:45:34,600
something fell from the sky. 
Imagine being in what's now the 

1821
01:45:34,600 --> 01:45:39,200
Yucatan Peninsula in Mexico on a
day 66,000,000 years ago. 

1822
01:45:40,080 --> 01:45:43,360
The morning is warm and humid, 
typical for this tropical 

1823
01:45:43,360 --> 01:45:46,800
coastline. 
In the inland forests, dinosaurs

1824
01:45:46,800 --> 01:45:50,240
are going about their daily 
business, herbivores browsing, 

1825
01:45:50,240 --> 01:45:53,400
small predators hunting and 
birds singing from the trees. 

1826
01:45:53,720 --> 01:45:57,240
Then moving at about 20 
kilometres per second, faster 

1827
01:45:57,240 --> 01:45:59,680
than you could track with your 
eyes if you could see it coming,

1828
01:46:00,120 --> 01:46:03,640
a rock about 10 kilometres in 
diameter enters the atmosphere. 

1829
01:46:04,280 --> 01:46:07,640
The air in front of it can't get
out of the way fast enough, so 

1830
01:46:07,640 --> 01:46:10,280
it compresses and heats to 
temperatures hotter than the 

1831
01:46:10,280 --> 01:46:14,080
surface of the Sun. 
The asteroid, Technically, it 

1832
01:46:14,080 --> 01:46:16,920
might have been a comet, but 
we'll call it an asteroid, is 

1833
01:46:16,920 --> 01:46:20,200
briefly surrounded by a bubble 
of super heated gas that 

1834
01:46:20,200 --> 01:46:23,800
radiates enough thermal energy 
to ignite forests hundreds of 

1835
01:46:23,800 --> 01:46:26,520
kilometres away. 
The impact itself releases 

1836
01:46:26,520 --> 01:46:29,720
energy equivalent to about 10 
billion Hiroshima bombs. 

1837
01:46:30,120 --> 01:46:34,000
The asteroid vaporizes instantly
along with a vast amount of the 

1838
01:46:34,000 --> 01:46:37,680
Earth's crust. 
A crater 150 kilometres in 

1839
01:46:37,680 --> 01:46:41,760
diameter forms in seconds. 
Rock liquefied by the impact 

1840
01:46:41,760 --> 01:46:44,960
splashes upward in a ring, 
creating mountains in minutes. 

1841
01:46:45,400 --> 01:46:48,640
Shock waves race through the 
Earth's crust like ripples in a 

1842
01:46:48,640 --> 01:46:52,600
pond, except these ripples are 
earthquakes of magnitude 11 or 

1843
01:46:52,600 --> 01:46:56,320
higher, far beyond anything in 
recorded human history. 

1844
01:46:56,680 --> 01:47:00,280
The debris from the impact, 
vaporized rock bits of asteroid 

1845
01:47:00,280 --> 01:47:03,760
fragments of crust, shoots 
upward into the atmosphere and 

1846
01:47:03,760 --> 01:47:06,760
beyond. 
Some material reaches escape 

1847
01:47:06,760 --> 01:47:09,040
velocity and actually leaves 
earth entirely. 

1848
01:47:09,680 --> 01:47:12,960
Other material falls back, re 
entering the atmosphere all over

1849
01:47:12,960 --> 01:47:16,280
the planet. 
As this material re enters at 

1850
01:47:16,280 --> 01:47:20,120
hypersonic speeds, it heats the 
atmosphere to oven like 

1851
01:47:20,120 --> 01:47:23,600
temperatures. 
Forests across the planet burst 

1852
01:47:23,600 --> 01:47:26,720
into flame. 
Animals without shelter are 

1853
01:47:26,720 --> 01:47:30,120
literally baked alive. 
Within minutes of the impact. 

1854
01:47:30,120 --> 01:47:34,240
Huge tsunamis race across the 
oceans, some perhaps hundreds of

1855
01:47:34,240 --> 01:47:37,800
metres high, obliterating 
coastal ecosystems around the 

1856
01:47:37,800 --> 01:47:41,920
Gulf of Mexico and beyond. 
Soot from the burning forests 

1857
01:47:41,920 --> 01:47:45,840
mixes with dust from the impact,
creating a thick shroud that 

1858
01:47:45,840 --> 01:47:48,720
blocks sunlight. 
Temperatures plummet as the 

1859
01:47:48,720 --> 01:47:52,400
planet is plunged into an impact
winter that could last months or

1860
01:47:52,400 --> 01:47:55,000
years. 
Photosynthesis essentially 

1861
01:47:55,000 --> 01:47:57,280
stops. 
Plants die from lack of 

1862
01:47:57,280 --> 01:47:59,720
sunlight. 
Herbivores die from lack of 

1863
01:47:59,720 --> 01:48:02,160
plants. 
Carnivores die from lack of 

1864
01:48:02,160 --> 01:48:05,080
prey. 
The food chains supporting 

1865
01:48:05,080 --> 01:48:09,480
complex ecosystems collapse like
dominoes in the oceans. 

1866
01:48:09,480 --> 01:48:13,240
Plankton, the base of marine 
food webs, die in massive 

1867
01:48:13,240 --> 01:48:17,200
numbers, causing cascading 
extinctions up the food chain. 

1868
01:48:17,480 --> 01:48:20,280
The extinction event that 
followed was the fifth major 

1869
01:48:20,280 --> 01:48:23,720
mass extinction in Earth's 
history and the one that finally

1870
01:48:23,720 --> 01:48:27,960
ended the age of dinosaurs. 
Non avian dinosaurs, which had 

1871
01:48:27,960 --> 01:48:31,600
ruled terrestrial ecosystems for
over 150 million years, 

1872
01:48:31,920 --> 01:48:36,480
completely disappeared. 
So did pterosaurs, the flying 

1873
01:48:36,480 --> 01:48:38,840
reptiles that had dominated the 
skies. 

1874
01:48:39,400 --> 01:48:43,040
Marine reptiles like mosasaurs 
and plesiosaurs vanished from 

1875
01:48:43,040 --> 01:48:47,080
the oceans. 
In total, about 75% of all 

1876
01:48:47,080 --> 01:48:50,600
species went extinct, but some 
creatures survived. 

1877
01:48:51,080 --> 01:48:54,880
Birds, technically flying 
dinosaurs, made it through, 

1878
01:48:55,160 --> 01:48:59,480
though many lineages were lost. 
Mammals survived, probably 

1879
01:48:59,480 --> 01:49:03,280
because they were small, ate 
diverse foods, and many lived in

1880
01:49:03,280 --> 01:49:06,320
Burrows that provided shelter 
from the immediate effects of 

1881
01:49:06,320 --> 01:49:09,640
the impact. 
Crocodiles and turtles survived,

1882
01:49:10,000 --> 01:49:13,000
possibly because they could go 
long periods without food. 

1883
01:49:13,520 --> 01:49:16,760
Snakes survived. 
Many groups of fish made it 

1884
01:49:16,760 --> 01:49:19,160
through. 
In the aftermath, the planet was

1885
01:49:19,160 --> 01:49:22,520
a devastated place. 
The forests were gone, replaced 

1886
01:49:22,520 --> 01:49:25,280
by vast expanses of dead trees 
and ash. 

1887
01:49:25,720 --> 01:49:27,600
The oceans were depleted of 
life. 

1888
01:49:28,240 --> 01:49:31,760
The survivors found themselves 
in a world with empty ecological

1889
01:49:31,760 --> 01:49:36,160
niches and reduced competition. 
Evolution, as it always does, 

1890
01:49:36,160 --> 01:49:39,840
began to fill the gaps. 
Mammals, which had spent 150 

1891
01:49:39,840 --> 01:49:43,560
million years as small, 
nocturnal creatures, suddenly 

1892
01:49:43,560 --> 01:49:46,000
had opportunities they'd never 
had before. 

1893
01:49:46,600 --> 01:49:50,240
Within a few million years, a 
blink of an eye in geological 

1894
01:49:50,240 --> 01:49:54,160
time, they're diversified into 
hundreds of new forms. 

1895
01:49:54,720 --> 01:49:58,040
Some remained small, but others 
grew larger, filling the 

1896
01:49:58,120 --> 01:50:01,120
ecological roles previously 
occupied by dinosaurs. 

1897
01:50:01,480 --> 01:50:04,840
By 50 million years ago, mammals
had become the dominant large 

1898
01:50:04,840 --> 01:50:07,880
animals on land. 
There were massive herbivores, 

1899
01:50:08,240 --> 01:50:12,320
fearsome predators and creatures
adapted for every environment 

1900
01:50:12,320 --> 01:50:14,600
from deserts to forests to 
oceans. 

1901
01:50:15,200 --> 01:50:19,080
Some mammals even returned to 
the sea, giving rise to whales 

1902
01:50:19,080 --> 01:50:22,000
and dolphins. 
Others took to the air, evolving

1903
01:50:22,000 --> 01:50:25,280
into bats. 
The age of mammals had begun as 

1904
01:50:25,280 --> 01:50:28,080
mammals diversified throughout 
the Xenozoic era. 

1905
01:50:28,400 --> 01:50:32,080
One particular group, the 
primates, was evolving in ways 

1906
01:50:32,080 --> 01:50:34,800
that would eventually change the
planet as profoundly as the 

1907
01:50:34,800 --> 01:50:38,680
evolution of photosynthesis or 
the colonisation of land. 

1908
01:50:39,080 --> 01:50:42,520
Early primates were small tree 
dwelling creatures that appeared

1909
01:50:42,520 --> 01:50:47,160
around 55,000,000 years ago. 
They're grasping hands and feet,

1910
01:50:47,480 --> 01:50:51,400
forward facing eyes for depth 
perception, and relatively large

1911
01:50:51,400 --> 01:50:54,920
brains for their body size. 
These features help them 

1912
01:50:54,920 --> 01:50:57,600
navigate the three-dimensional 
environment of the forest 

1913
01:50:57,600 --> 01:51:01,120
canopy. 
Over millions of years, primates

1914
01:51:01,120 --> 01:51:05,040
diversified into lemurs, monkeys
and apes. 

1915
01:51:05,400 --> 01:51:08,760
Around 7,000,000 years ago in 
Africa, something significant 

1916
01:51:08,760 --> 01:51:12,240
happened in the ape lineage. 
Some apes began spending more 

1917
01:51:12,240 --> 01:51:14,880
time on the ground and walking 
upright on 2 legs. 

1918
01:51:15,280 --> 01:51:18,720
This bipedalism freed their 
hands for carrying objects and 

1919
01:51:18,720 --> 01:51:21,840
using tools. 
It also changed their anatomy in

1920
01:51:21,840 --> 01:51:25,440
ways that would prove crucial. 
Their pelvis shifted to support 

1921
01:51:25,440 --> 01:51:29,640
upright walking, their spine 
curved in an S shape, and their 

1922
01:51:29,640 --> 01:51:32,920
skull balanced directly on top 
of their spine rather than 

1923
01:51:32,920 --> 01:51:35,960
jutting forward. 
These early hominins, or human 

1924
01:51:35,960 --> 01:51:39,080
ancestors, weren't dramatically 
different from other apes. 

1925
01:51:39,080 --> 01:51:43,160
Initially, they had brains about
the size of modern chimpanzees 

1926
01:51:43,440 --> 01:51:46,440
and probably lived in small 
social groups in woodland and 

1927
01:51:46,440 --> 01:51:49,760
Savannah environments. 
But they were starting down a 

1928
01:51:49,760 --> 01:51:52,000
path that would lead to 
something unprecedented. 

1929
01:51:52,360 --> 01:51:55,920
Over the next several million 
years, various hominin species 

1930
01:51:55,920 --> 01:51:59,240
appeared, experimented with 
different strategies for 

1931
01:51:59,240 --> 01:52:01,800
survival, and mostly went 
extinct. 

1932
01:52:02,440 --> 01:52:07,160
Australopithecus afarensis, the 
species that includes the famous

1933
01:52:07,160 --> 01:52:11,480
fossil Lucy, walked upright but 
still climbed trees and had a 

1934
01:52:11,480 --> 01:52:15,600
relatively small brain. 
Paranthropus species had massive

1935
01:52:15,600 --> 01:52:17,920
jaws for processing tough plant 
material. 

1936
01:52:18,680 --> 01:52:22,240
Various species of early Homo 
began making more sophisticated 

1937
01:52:22,240 --> 01:52:23,880
stone tools and eating more 
meat. 

1938
01:52:24,280 --> 01:52:28,360
Around 2,000,000 years ago, one 
lineage, our direct ancestors, 

1939
01:52:28,760 --> 01:52:33,360
began evolving larger brains. 
This required significant energy

1940
01:52:33,360 --> 01:52:35,560
investment. 
Brains are metabolically 

1941
01:52:35,560 --> 01:52:40,280
expensive and created a problem.
Infants needed to be born 

1942
01:52:40,360 --> 01:52:42,760
earlier in their development 
because their large heads 

1943
01:52:42,760 --> 01:52:45,040
wouldn't fit through the birth 
canal if they waited much 

1944
01:52:45,040 --> 01:52:48,360
longer. 
Human infants are remarkably 

1945
01:52:48,360 --> 01:52:51,920
helpless compared to other 
mammals, requiring extended 

1946
01:52:51,920 --> 01:52:54,840
parental care. 
This helplessness may have 

1947
01:52:54,840 --> 01:52:57,400
driven increased social 
cooperation and learning, 

1948
01:52:57,880 --> 01:53:01,120
creating a feedback loop where 
social species with big brains 

1949
01:53:01,120 --> 01:53:04,600
had more successful offspring, 
leading to even more social 

1950
01:53:04,600 --> 01:53:09,680
species with even bigger brains.
By 300,000 years ago, Homo 

1951
01:53:09,680 --> 01:53:13,640
sapiens, modern humans 
anatomically indistinguishable 

1952
01:53:13,640 --> 01:53:15,920
from you, had appeared in 
Africa. 

1953
01:53:16,760 --> 01:53:19,440
We weren't alone. 
Several other human species 

1954
01:53:19,440 --> 01:53:23,920
existed, including Neanderthals 
in Europe and Denisovans in 

1955
01:53:23,920 --> 01:53:26,360
Asia. 
These other species were 

1956
01:53:26,360 --> 01:53:30,480
intelligent, used tools, had 
culture and art, and probably 

1957
01:53:30,480 --> 01:53:33,800
had language. 
But for reasons still debated, 

1958
01:53:34,000 --> 01:53:38,080
they eventually went extinct, 
leaving Homo sapiens as the only

1959
01:53:38,080 --> 01:53:42,240
surviving human species. 
Around 70,000 years ago, modern 

1960
01:53:42,240 --> 01:53:46,360
humans began migrating out of 
Africa, spreading across Asia, 

1961
01:53:46,400 --> 01:53:49,200
Europe, Australia and eventually
the Americas. 

1962
01:53:49,720 --> 01:53:54,040
They adapted every environment, 
from Arctic tundra to tropical 

1963
01:53:54,040 --> 01:53:57,320
rainforests, from deserts to 
islands. 

1964
01:53:58,160 --> 01:54:00,920
Unlike other animals that adapt 
to new environments through 

1965
01:54:00,920 --> 01:54:05,280
biological evolution, humans 
adapted largely through cultural

1966
01:54:05,280 --> 01:54:10,120
evolution, learning new skills, 
inventing new technologies, and 

1967
01:54:10,120 --> 01:54:12,280
passing knowledge between 
generations. 

1968
01:54:12,640 --> 01:54:16,360
About 12,000 years ago, humans 
began domesticating plants and 

1969
01:54:16,360 --> 01:54:20,720
animals, inventing agriculture. 
This was a turning point in 

1970
01:54:20,720 --> 01:54:22,680
human history and Earth's 
history. 

1971
01:54:23,280 --> 01:54:26,200
Farming allowed humans to 
produce more food, support 

1972
01:54:26,200 --> 01:54:29,720
larger populations, and create 
permanent settlements. 

1973
01:54:30,520 --> 01:54:34,240
But it also tied human societies
to particular pieces of land, 

1974
01:54:34,560 --> 01:54:38,080
created social hierarchies, and 
began the process of 

1975
01:54:38,080 --> 01:54:41,600
transforming natural landscapes 
into agricultural ones. 

1976
01:54:41,840 --> 01:54:46,480
Cities appeared, civilizations 
rose and fell, and technologies 

1977
01:54:46,480 --> 01:54:50,040
advanced. 
Humans began changing the planet

1978
01:54:50,040 --> 01:54:53,480
at scales that would have been 
unimaginable to their ancestors.

1979
01:54:54,080 --> 01:54:57,800
They cleared forests for 
agriculture, redirected rivers, 

1980
01:54:58,080 --> 01:55:01,880
built massive structures, and 
eventually began burning fossil 

1981
01:55:01,880 --> 01:55:04,440
fuels. 
Those ancient Carboniferous 

1982
01:55:04,440 --> 01:55:08,840
forests transformed by heat and 
pressure into coal, oil and gas.

1983
01:55:09,200 --> 01:55:13,280
Today, Earth's surface has been 
profoundly reshaped by human 

1984
01:55:13,280 --> 01:55:16,960
activity. 
We've converted about 40% of the

1985
01:55:16,960 --> 01:55:19,280
planet's ice free land to 
agriculture. 

1986
01:55:19,920 --> 01:55:22,760
We've built cities that house 
billions of people. 

1987
01:55:23,320 --> 01:55:26,920
We've driven many species to 
extinction while deliberately 

1988
01:55:26,920 --> 01:55:28,720
spreading others around the 
world. 

1989
01:55:29,480 --> 01:55:32,560
We've altered the chemistry of 
the atmosphere by burning fossil

1990
01:55:32,560 --> 01:55:36,760
fuels, increasing carbon dioxide
levels to heights not seen for 

1991
01:55:36,760 --> 01:55:40,320
millions of years. 
Yet Earth remains fundamentally 

1992
01:55:40,320 --> 01:55:43,760
a living planet. 
The oceans still teem with life,

1993
01:55:44,160 --> 01:55:47,280
from microscopic plankton to 
enormous whales. 

1994
01:55:47,760 --> 01:55:51,360
Forests still grow, 
photosynthesising and producing 

1995
01:55:51,360 --> 01:55:54,560
oxygen. 
Microbes still process nutrients

1996
01:55:54,560 --> 01:56:00,120
and decompose dead material. 
The rock cycle continues slowly 

1997
01:56:00,120 --> 01:56:02,640
but inexorably recycling Earth's
crust. 

1998
01:56:03,280 --> 01:56:07,240
Plate tectonics still move 
continents, build mountains, and

1999
01:56:07,240 --> 01:56:11,080
create new oceanic crust. 
If you could somehow see Earth 

2000
01:56:11,080 --> 01:56:14,920
from space right now, you'd see 
the same basic features that 

2001
01:56:14,920 --> 01:56:17,720
have characterized the planet 
for hundreds of millions of 

2002
01:56:17,720 --> 01:56:20,960
years. 
Blue oceans, white clouds, and 

2003
01:56:20,960 --> 01:56:24,000
Greenland masses. 
The differences from the 

2004
01:56:24,000 --> 01:56:27,720
Cretaceous or Jurassic would be 
subtle from orbit, different 

2005
01:56:27,720 --> 01:56:31,080
configurations of continents, 
perhaps different patterns of 

2006
01:56:31,080 --> 01:56:34,280
vegetation, but still 
recognisably Earth. 

2007
01:56:34,680 --> 01:56:38,720
Yet the planet is constantly 
changing, as it always has. 

2008
01:56:39,520 --> 01:56:44,080
Climate shifts, continents 
drift, and species evolve and go

2009
01:56:44,080 --> 01:56:46,800
extinct. 
The Earth you're sitting on 

2010
01:56:46,800 --> 01:56:50,440
right now is not the same as the
Earth of a million years ago or 

2011
01:56:50,440 --> 01:56:53,960
a million years hence. 
Change is the only constant in 

2012
01:56:53,960 --> 01:56:56,760
Earth's long history. 
As you prepare for sleep, 

2013
01:56:56,760 --> 01:56:59,440
consider the extraordinary 
journey we've traced tonight 

2014
01:57:00,080 --> 01:57:03,560
from a molten ball of rock to a 
living planet teeming with 

2015
01:57:03,560 --> 01:57:08,760
complexity. 4 1/2 billion years 
is a span of time that defies 

2016
01:57:08,760 --> 01:57:12,240
human comprehension. 
If Earth's entire history were 

2017
01:57:12,240 --> 01:57:15,840
compressed into a single year, 
with Earth forming on January 

2018
01:57:15,840 --> 01:57:19,800
1st, the first life would appear
in February, but complex animals

2019
01:57:19,800 --> 01:57:21,560
wouldn't show up until mid 
November. 

2020
01:57:22,240 --> 01:57:24,960
Dinosaurs would rule for about a
week in December. 

2021
01:57:25,720 --> 01:57:29,360
All of human history, from the 
first civilizations to today, 

2022
01:57:29,640 --> 01:57:32,320
would occur in the last few 
minutes before midnight on 

2023
01:57:32,320 --> 01:57:35,320
December 31st. 
This perspective can make our 

2024
01:57:35,320 --> 01:57:38,560
individual lives seem 
insignificant, but perhaps 

2025
01:57:38,560 --> 01:57:41,640
that's not quite right. 
Every atom in your body was 

2026
01:57:41,640 --> 01:57:44,600
forged in the heart of a star, 
or in the violent collision of 

2027
01:57:44,600 --> 01:57:48,360
the neutron stars. 
The calcium in your bones, the 

2028
01:57:48,360 --> 01:57:52,000
iron in your blood, and the 
oxygen you breathe all have 

2029
01:57:52,000 --> 01:57:55,200
cosmic origins stretching back 
billions of years. 

2030
01:57:55,840 --> 01:57:59,240
You're quite literally made of 
Stardust, assembled through 

2031
01:57:59,240 --> 01:58:02,680
processes that have taken the 
entire age of the universe to 

2032
01:58:02,680 --> 01:58:05,360
unfold. 
The water you drank today might 

2033
01:58:05,360 --> 01:58:08,640
have fallen as rain on Jurassic 
dinosaurs, flowed through 

2034
01:58:08,640 --> 01:58:12,680
Carboniferous forests, or 
existed in the first oceans that

2035
01:58:12,680 --> 01:58:14,600
formed when Earth's surface 
cooled. 

2036
01:58:15,360 --> 01:58:19,640
Water cycles through Earth's 
systems, evaporating, condensing

2037
01:58:19,640 --> 01:58:22,760
and flowing, being recycled 
endlessly. 

2038
01:58:23,520 --> 01:58:26,680
Every glass of water contains 
molecules that have been part of

2039
01:58:26,680 --> 01:58:29,200
countless living things 
throughout Earth's history. 

2040
01:58:29,600 --> 01:58:32,440
The air you breathe is the 
product of billions of years of 

2041
01:58:32,440 --> 01:58:34,800
biological and geological 
processes. 

2042
01:58:35,320 --> 01:58:39,040
The nitrogen came from volcanic 
out gassing and cosmic dust. 

2043
01:58:39,600 --> 01:58:43,160
The oxygen was produced by 
cyanobacteria and plants over 

2044
01:58:43,160 --> 01:58:46,600
billions of years. 
The trace of carbon dioxide 

2045
01:58:46,600 --> 01:58:49,640
connects you to every plant 
currently photosynthesizing, 

2046
01:58:50,000 --> 01:58:53,080
every animal currently 
breathing, every volcano 

2047
01:58:53,080 --> 01:58:56,240
currently erupting, and every 
vehicle currently running. 

2048
01:58:56,640 --> 01:58:59,840
You exist because of an unbroken
chain of survival and 

2049
01:58:59,840 --> 01:59:03,000
reproduction stretching back to 
those first replicating 

2050
01:59:03,000 --> 01:59:05,360
molecules in Earth's primordial 
oceans. 

2051
01:59:06,320 --> 01:59:10,440
Every one of your ancestors, 
from bacteria to fish to mammals

2052
01:59:10,440 --> 01:59:13,640
to primates, successfully 
survived long enough to 

2053
01:59:13,640 --> 01:59:16,960
reproduce. 
You're the product of 4 billion 

2054
01:59:16,960 --> 01:59:20,480
years of evolutionary success, 
the latest chapter in the 

2055
01:59:20,480 --> 01:59:23,400
greatest story ever told. 
But you're also part of 

2056
01:59:23,400 --> 01:59:25,720
something larger than your 
individual story. 

2057
01:59:26,240 --> 01:59:28,640
You're a temporary arrangement 
of atoms that Earth has 

2058
01:59:28,640 --> 01:59:31,600
assembled, atoms that will 
eventually return to the 

2059
01:59:31,600 --> 01:59:34,600
planet's cycles. 
When you die, your body will 

2060
01:59:34,600 --> 01:59:38,360
decompose, releasing nutrients 
that will be taken up by plants 

2061
01:59:38,360 --> 01:59:41,800
and microbes, continuing the 
great recycling that has 

2062
01:59:41,800 --> 01:59:44,080
characterized Earth for billions
of years. 

2063
01:59:44,800 --> 01:59:48,360
Nothing is truly lost. 
Everything is transformed and 

2064
01:59:48,360 --> 01:59:51,080
reused. 
This perspective on deep time 

2065
01:59:51,080 --> 01:59:54,440
can be oddly comforting. 
Your worries and stresses, the 

2066
01:59:54,440 --> 01:59:57,160
things that keep you awake at 
night, are real and valid in the

2067
01:59:57,160 --> 02:00:01,080
moment, but they're also 
temporary, fleeting concerns. 

2068
02:00:01,080 --> 02:00:05,800
In the vastness of geological 
time, mountains rise and erode, 

2069
02:00:06,200 --> 02:00:09,840
oceans open and close, 
continents drift. 

2070
02:00:10,200 --> 02:00:12,760
Life persists, adapts and 
changes. 

2071
02:00:13,160 --> 02:00:15,920
Earth endures. 
The planet beneath you has 

2072
02:00:15,920 --> 02:00:19,520
survived asteroid impacts, 
volcanic super eruptions, 

2073
02:00:19,760 --> 02:00:22,520
snowball glaciations, and mass 
extinctions. 

2074
02:00:23,240 --> 02:00:26,320
It has transformed from a 
lifeless ball of rock to a world

2075
02:00:26,320 --> 02:00:30,440
where microscopic organisms can 
evolve over billions of years 

2076
02:00:30,720 --> 02:00:33,440
into creatures capable of 
understanding their own 

2077
02:00:33,440 --> 02:00:37,040
evolutionary history. 
That's perhaps the most 

2078
02:00:37,040 --> 02:00:40,880
remarkable thing of all, that 
the universe can, through 

2079
02:00:40,880 --> 02:00:44,600
processes we're still working to
understand, create entities 

2080
02:00:44,600 --> 02:00:47,360
capable of contemplating the 
universe itself. 

2081
02:00:47,760 --> 02:00:51,200
Tomorrow morning, when you wake 
up, you'll be one day older. 

2082
02:00:51,840 --> 02:00:53,840
But Earth will be older by a 
day, too. 

2083
02:00:54,280 --> 02:00:57,440
The day in which its continents 
will have drifted fractions of a

2084
02:00:57,440 --> 02:00:59,960
millimetre. 
The day in which millions of 

2085
02:00:59,960 --> 02:01:02,200
organisms will have been born 
and died. 

2086
02:01:02,600 --> 02:01:06,360
A day in which rock weathered 
and soil formed and water cycled

2087
02:01:06,360 --> 02:01:08,960
and life continued. 
You're a participant in this 

2088
02:01:08,960 --> 02:01:12,680
ongoing story, contributing your
own small chapter to Earth's 

2089
02:01:12,680 --> 02:01:16,040
biography. 
The choices you make, the things

2090
02:01:16,040 --> 02:01:19,640
you create and the people you 
influence all become part of the

2091
02:01:19,640 --> 02:01:22,080
planet's history, however 
briefly. 

2092
02:01:23,080 --> 02:01:26,000
You're not just living on Earth,
you're part of Earth. 

2093
02:01:26,480 --> 02:01:29,520
A temporary expression of the 
planet's capacity to organise 

2094
02:01:29,520 --> 02:01:34,720
matter into self aware forms. 
Sleep now and dream of deep time

2095
02:01:34,720 --> 02:01:37,960
if you wish. 
Dream of ancient oceans and 

2096
02:01:37,960 --> 02:01:42,760
Cambrian seas, of forests that 
became coal, of continents 

2097
02:01:42,760 --> 02:01:45,240
drifting like slow ships on the 
mantle. 

2098
02:01:45,880 --> 02:01:48,760
Dream of your ancestors 
stretching back through mammals 

2099
02:01:48,760 --> 02:01:53,160
and reptiles and fish and simple
cells to the very beginning of 

2100
02:01:53,160 --> 02:01:56,360
life itself. 
Dream of a planet that has been 

2101
02:01:56,360 --> 02:02:01,800
patient for 4.5 billion years, 
slowly becoming a world where 

2102
02:02:01,800 --> 02:02:04,360
creatures like you could exist 
to tell its story. 

2103
02:02:04,720 --> 02:02:07,480
And when you wake tomorrow, 
remember that you're living on 

2104
02:02:07,480 --> 02:02:11,360
the surface of a living planet 
one day, in a story that began 

2105
02:02:11,360 --> 02:02:15,120
billions of years ago and will 
continue long after you're gone.

2106
02:02:15,640 --> 02:02:18,680
That's not diminishing, it's 
connecting. 

2107
02:02:19,600 --> 02:02:23,480
You're part of something vast 
and ancient and ongoing, a 

2108
02:02:23,520 --> 02:02:26,120
participant in the grandest 
story ever told. 

2109
02:02:26,400 --> 02:02:30,600
Rest well, child of Stardust, 
descendant of the first 

2110
02:02:30,600 --> 02:02:34,520
replicating molecules, 
beneficiary of 4 billion years 

2111
02:02:34,520 --> 02:02:37,320
of evolution. 
Earth will still be here when 

2112
02:02:37,320 --> 02:02:41,680
you wake, continuing its slow 
dance through space, carrying 

2113
02:02:41,680 --> 02:02:44,720
you and billions of other 
organisms through another day of

2114
02:02:44,720 --> 02:02:55,340
the longest story ever told. 
Battle of Gettysburg began on 

2115
02:02:55,340 --> 02:03:00,760
the morning of July 1st, 1863. 
It was a warm summer day, the 

2116
02:03:00,760 --> 02:03:03,440
kind where the golden light of 
dawn touched the fields and 

2117
02:03:03,440 --> 02:03:06,760
forests with a serene glow that 
the tranquillity of the 

2118
02:03:06,760 --> 02:03:09,680
Pennsylvania countryside would 
soon be shattered by the Thunder

2119
02:03:09,680 --> 02:03:12,080
of battle. 
This clash was not merely 

2120
02:03:12,080 --> 02:03:14,760
another skirmish in the long and
bloody conflict of the Civil 

2121
02:03:14,760 --> 02:03:17,560
War. 
It was a turning point, a moment

2122
02:03:17,560 --> 02:03:19,880
where the fate of the Union and 
the Confederacy hung 

2123
02:03:19,880 --> 02:03:23,480
precariously in the balance. 
General Robert E Lee, commanding

2124
02:03:23,480 --> 02:03:26,560
the Confederate Army of Northern
Virginia, had set his sights on 

2125
02:03:26,560 --> 02:03:30,280
a bold invasion of the North. 
His army, emboldened by a string

2126
02:03:30,280 --> 02:03:33,040
of victories, marched into 
Pennsylvania with the hope of 

2127
02:03:33,040 --> 02:03:36,360
striking A decisive blow that 
wood forest the Union to sue for

2128
02:03:36,360 --> 02:03:38,840
peace. 
Lee's strategy was not just 

2129
02:03:38,840 --> 02:03:41,520
about military conquest. 
It was about shaking the 

2130
02:03:41,520 --> 02:03:45,200
Northern resolve, bringing the 
war to Union soil and perhaps 

2131
02:03:45,200 --> 02:03:47,880
swaying foreign powers to 
recognize the Confederacy. 

2132
02:03:48,800 --> 02:03:51,720
On the Union side, General 
George G Meade had recently 

2133
02:03:51,720 --> 02:03:53,640
taken command of the Army of the
Potomac. 

2134
02:03:54,200 --> 02:03:57,880
His task was daunting, to stop 
Lee's advance and protect the 

2135
02:03:57,880 --> 02:04:00,840
Union's heartland. 
The soldiers under his command 

2136
02:04:00,840 --> 02:04:03,720
were weary from years of 
conflict, but their resolve to 

2137
02:04:03,720 --> 02:04:06,200
defend their homeland and 
preserve the Union burned 

2138
02:04:06,200 --> 02:04:09,240
brightly. 
The two armies converged near 

2139
02:04:09,240 --> 02:04:13,360
the small town of Gettysburg, a 
place of rolling hills, fertile 

2140
02:04:13,360 --> 02:04:17,400
farmland, and winding roads. 
It was an unlikely setting for 

2141
02:04:17,400 --> 02:04:20,000
one of the most significant 
battles in American history. 

2142
02:04:20,920 --> 02:04:24,480
On the first day, the fighting 
began West of the town as 

2143
02:04:24,480 --> 02:04:26,920
Confederate forces encountered 
Union cavalry. 

2144
02:04:27,480 --> 02:04:30,360
The clash was fierce and 
chaotic, with both sides 

2145
02:04:30,360 --> 02:04:31,920
scrambling to gain the upper 
hand. 

2146
02:04:32,600 --> 02:04:35,760
By day's end, the Confederates 
had pushed Union forces back 

2147
02:04:35,760 --> 02:04:38,560
through the town and onto the 
high ground to the South, 

2148
02:04:38,840 --> 02:04:42,680
securing an early advantage. 
The second day of the battle 

2149
02:04:42,680 --> 02:04:44,360
dawned with tension thick in the
air. 

2150
02:04:44,880 --> 02:04:48,280
The Union Army had established a
strong defensive position along 

2151
02:04:48,280 --> 02:04:51,520
a series of hills and ridges 
known as Cemetery Hill, Culps 

2152
02:04:51,520 --> 02:04:55,240
Hill and Little Round Top. 
Lee, confident in his army 

2153
02:04:55,240 --> 02:04:57,800
strength, launched a series of 
attacks to break the Union 

2154
02:04:57,800 --> 02:05:00,560
lines. 
The fighting on July 2nd was 

2155
02:05:00,560 --> 02:05:04,200
intense and bloody. 
At Little Round Top, Union 

2156
02:05:04,200 --> 02:05:06,760
Colonel Joshua Lawrence 
Chamberlain and the 20th Main 

2157
02:05:06,760 --> 02:05:10,480
Regiment made a heroic stand to 
defend the hills southern flank.

2158
02:05:11,200 --> 02:05:14,520
Outnumbered and nearly out of 
ammunition, Chamberlain ordered 

2159
02:05:14,520 --> 02:05:17,440
a desperate bayonet charge that 
drove the Confederates back and 

2160
02:05:17,440 --> 02:05:21,240
secured the Union's position. 
It was a moment of extraordinary

2161
02:05:21,240 --> 02:05:24,440
courage, one that would later be
remembered as a turning point in

2162
02:05:24,440 --> 02:05:27,240
the battle. 
Elsewhere, the fields of wheat 

2163
02:05:27,240 --> 02:05:30,120
and Peach orchards became 
killing grounds, their beauty 

2164
02:05:30,120 --> 02:05:34,000
scarred by the carnage of war. 
The air was thick with smoke and

2165
02:05:34,000 --> 02:05:37,280
the cries of the wounded 
soldiers on both sides fought 

2166
02:05:37,280 --> 02:05:40,200
with ferocious determination, 
knowing that the stakes were 

2167
02:05:40,200 --> 02:05:42,960
higher than ever. 
By the end of the day, the Union

2168
02:05:42,960 --> 02:05:45,120
lines had held, but at a 
terrible cost. 

2169
02:05:45,680 --> 02:05:49,200
The 3rd and final day of the 
battle, July 3rd, brought the 

2170
02:05:49,200 --> 02:05:51,560
infamous assault known as 
Pickett's Charge. 

2171
02:05:52,120 --> 02:05:55,600
Lee, believing that concentrated
attack on the Union Centre could

2172
02:05:55,600 --> 02:06:00,240
break their lines, ordered 
12,500 Confederate soldiers to 

2173
02:06:00,240 --> 02:06:03,560
March across open fields under 
heavy Union artillery fire. 

2174
02:06:04,200 --> 02:06:06,920
The sight of that charge was 
both awe inspiring and 

2175
02:06:06,920 --> 02:06:09,000
harrowing. 
The Confederate soldiers 

2176
02:06:09,000 --> 02:06:12,120
advanced in tight ranks, their 
banners waving, their 

2177
02:06:12,120 --> 02:06:16,000
determination unyielding. 
But the Union defenders, 

2178
02:06:16,240 --> 02:06:19,840
entrenched on Cemetery Ridge 
unleashed a devastating barrage 

2179
02:06:19,840 --> 02:06:23,120
of cannon and musket fire. 
The fields became a scene of 

2180
02:06:23,120 --> 02:06:25,040
chaos as men fell by the 
hundreds. 

2181
02:06:25,520 --> 02:06:28,400
Despite their bravery, the 
Confederate soldiers could not 

2182
02:06:28,400 --> 02:06:32,040
overcome the Union's defences. 
The charge was repelled, and the

2183
02:06:32,040 --> 02:06:33,680
fields were littered with the 
fallen. 

2184
02:06:35,080 --> 02:06:38,960
As the sunset on July 3rd, the 
Battle of Gettysburg came to an 

2185
02:06:38,960 --> 02:06:41,640
end. 
Lee, realizing that his army 

2186
02:06:41,640 --> 02:06:44,640
could not sustain another 
assault, began the long retreat 

2187
02:06:44,640 --> 02:06:47,800
back to Virginia. 
The Union army, though battered 

2188
02:06:47,800 --> 02:06:49,920
and exhausted, had won a 
decisive victory. 

2189
02:06:50,520 --> 02:06:53,400
It was a moment of relief and 
triumph for the North, a turning

2190
02:06:53,400 --> 02:06:55,400
point that shifted the momentum 
of the war. 

2191
02:06:55,920 --> 02:06:57,600
The cost of the battle was 
staggering. 

2192
02:06:58,000 --> 02:07:01,400
Over 50,000 soldiers were 
killed, wounded, or missing. 

2193
02:07:02,000 --> 02:07:05,000
The fields of Gettysburg, once 
peaceful and lush, were now 

2194
02:07:05,000 --> 02:07:08,600
marked by the scars of war. 
Families in both the North and 

2195
02:07:08,600 --> 02:07:11,840
the South mourned the loss of 
loved ones, their lives forever 

2196
02:07:11,840 --> 02:07:15,000
changed by the conflict. 
In the months that followed, 

2197
02:07:15,280 --> 02:07:18,280
Gettysburg became a symbol of 
sacrifice and resilience. 

2198
02:07:18,880 --> 02:07:23,120
On November 19th, 1863, 
President Abraham Lincoln 

2199
02:07:23,120 --> 02:07:25,640
delivered the Gettysburg Address
at the dedication of the 

2200
02:07:25,640 --> 02:07:29,200
Soldiers National Cemetery. 
His words, though brief, 

2201
02:07:29,520 --> 02:07:32,280
captured the essence of what the
battle had come to represent. 

2202
02:07:32,880 --> 02:07:36,400
He spoke of a nation conceived 
in liberty and dedicated to the 

2203
02:07:36,400 --> 02:07:38,800
proposition that all men are 
created equal. 

2204
02:07:39,360 --> 02:07:42,040
He reminded the audience that 
the soldiers who had fought and 

2205
02:07:42,040 --> 02:07:44,720
died at Gettysburg had done so 
to ensure that freedom and 

2206
02:07:44,720 --> 02:07:48,320
democracy would endure. 
The Battle of Gettysburg remains

2207
02:07:48,320 --> 02:07:50,720
one of the most studied and 
remembered events in American 

2208
02:07:50,720 --> 02:07:53,280
history. 
It was a moment of profound 

2209
02:07:53,280 --> 02:07:56,720
struggle and sacrifice, a 
reminder of the costs of war and

2210
02:07:56,720 --> 02:07:58,360
the resilience of the human 
spirit. 

2211
02:07:59,080 --> 02:08:02,520
The bravery of the soldiers on 
both sides, their dedication to 

2212
02:08:02,520 --> 02:08:05,800
their causes, and the impact of 
their actions continue to echo 

2213
02:08:05,800 --> 02:08:08,960
through time. 
As you drift into sleep, let the

2214
02:08:08,960 --> 02:08:11,880
story of Gettysburg fill your 
mind with a sense of reverence 

2215
02:08:11,880 --> 02:08:14,520
and reflection. 
Imagine the stillness of the 

2216
02:08:14,520 --> 02:08:17,880
fields after the battle, the 
quiet wind carrying the memory 

2217
02:08:17,880 --> 02:08:20,840
of those who fought and fell. 
Feel the weight of their 

2218
02:08:20,840 --> 02:08:23,920
sacrifice, but also the hope 
that their struggle helped to 

2219
02:08:23,920 --> 02:08:27,320
shape a better future. 
The aftermath of the Battle of 

2220
02:08:27,320 --> 02:08:30,840
Gettysburg left an indelible 
mark not only on the landscape 

2221
02:08:30,840 --> 02:08:34,080
of Pennsylvania, but also on the
hearts and minds of the American

2222
02:08:34,080 --> 02:08:36,520
people. 
The quiet town that had seen a 

2223
02:08:36,520 --> 02:08:39,640
horrific convergence of armies 
now bore the weight of countless

2224
02:08:39,640 --> 02:08:42,680
graves hastily dug for the 
fallen soldiers. 

2225
02:08:43,120 --> 02:08:46,440
The once lush fields, orchards, 
and rolling hills were now 

2226
02:08:46,440 --> 02:08:49,800
etched with scars of war 
trenches, shattered fences, and 

2227
02:08:49,800 --> 02:08:52,840
abandoned artillery. 
In the days immediately 

2228
02:08:52,840 --> 02:08:55,280
following the battle, the 
townspeople of Gettysburg rose 

2229
02:08:55,280 --> 02:08:57,520
to meet the grim reality of what
had unfolded. 

2230
02:08:58,080 --> 02:09:00,480
Civilians who had sought shelter
during the three days of 

2231
02:09:00,480 --> 02:09:03,040
fighting now ventured out to 
help the wounded and dying. 

2232
02:09:03,600 --> 02:09:06,600
Homes, barns, and churches were 
transformed into makeshift 

2233
02:09:06,600 --> 02:09:09,600
hospitals. 
Women, men, and even children 

2234
02:09:09,600 --> 02:09:12,680
worked tirelessly to bring 
comfort to soldiers, regardless 

2235
02:09:12,680 --> 02:09:16,000
of the uniforms they wore. 
The lines of battle blurred in 

2236
02:09:16,000 --> 02:09:19,360
the face of shared humanity. 
Doctors and nurses were 

2237
02:09:19,360 --> 02:09:23,000
overwhelmed by the sheer number 
of wounded, Medical supplies 

2238
02:09:23,000 --> 02:09:26,320
were scarce, and the knowledge 
of sanitation was rudimentary at

2239
02:09:26,320 --> 02:09:28,400
best. 
Despite the primitive 

2240
02:09:28,400 --> 02:09:31,760
conditions, countless acts of 
compassion unfolded as 

2241
02:09:31,760 --> 02:09:35,440
townspeople did what they could 
to save lives or bring solace to

2242
02:09:35,440 --> 02:09:39,160
those whose time was short. 
As the Confederate Army 

2243
02:09:39,160 --> 02:09:42,520
retreated southward, General Lee
bore the burden of his army's 

2244
02:09:42,520 --> 02:09:44,800
defeat. 
The invasion of the North had 

2245
02:09:44,800 --> 02:09:47,880
failed, and the high hopes of a 
quick victory and a potential 

2246
02:09:47,880 --> 02:09:51,640
peace agreement were dashed. 
For Lee, Gettysburg marked a 

2247
02:09:51,640 --> 02:09:55,000
turning point, a moment when the
tide of the war began to turn 

2248
02:09:55,000 --> 02:09:56,880
decisively against the 
Confederacy. 

2249
02:09:57,480 --> 02:10:01,280
The loss of so many men and the 
inability to break Union resolve

2250
02:10:01,560 --> 02:10:04,400
were blows from which his forces
would never fully recover. 

2251
02:10:04,960 --> 02:10:08,120
For the Union, the victory at 
Gettysburg was a critical morale

2252
02:10:08,120 --> 02:10:10,680
boost. 
General Mead, despite some 

2253
02:10:10,680 --> 02:10:13,240
criticism for not pursuing Lee's
retreating army more 

2254
02:10:13,240 --> 02:10:16,200
aggressively, had achieved what 
many thought impossible. 

2255
02:10:16,720 --> 02:10:19,520
The Army of the Potomac had 
stood firm against Lee's forces,

2256
02:10:19,840 --> 02:10:22,360
proving that the Union could 
hold its ground and turn the 

2257
02:10:22,360 --> 02:10:25,400
tide of the war. 
The significance of Gettysburg 

2258
02:10:25,400 --> 02:10:27,040
reached far beyond the 
battlefield. 

2259
02:10:27,480 --> 02:10:30,200
It became a symbol of the 
broader struggle, the fight to 

2260
02:10:30,200 --> 02:10:32,680
preserve the Union and the 
principles upon which it was 

2261
02:10:32,680 --> 02:10:34,920
founded. 
In the months following the 

2262
02:10:34,920 --> 02:10:38,240
battle, efforts began to ensure 
that the sacrifices made there 

2263
02:10:38,240 --> 02:10:42,000
would not be forgotten. 
One of the most poignant moments

2264
02:10:42,000 --> 02:10:46,040
came on November 19th, 1863, 
with the dedication of the 

2265
02:10:46,040 --> 02:10:48,160
Soldiers National Cemetery at 
Gettysburg. 

2266
02:10:48,880 --> 02:10:52,240
President Abraham Lincoln was 
invited to deliver a few remarks

2267
02:10:52,600 --> 02:10:55,840
following a lengthy oration by 
Edward Everett, a renowned 

2268
02:10:55,840 --> 02:10:59,000
speaker of the time. 
Lincoln's address, though brief,

2269
02:10:59,000 --> 02:11:01,440
would become one of the most 
enduring speeches in American 

2270
02:11:01,440 --> 02:11:04,080
history. 
Standing on the blood soaked 

2271
02:11:04,080 --> 02:11:07,520
fields of Gettysburg, Lincoln 
spoke not only to honour the 

2272
02:11:07,520 --> 02:11:10,080
dead, but to remind the living 
of the greater cause for which 

2273
02:11:10,080 --> 02:11:12,960
they had fought. 
His words, beginning with the 

2274
02:11:12,960 --> 02:11:17,120
now iconic phrase 4 score and 
seven years ago, framed the 

2275
02:11:17,120 --> 02:11:20,040
battle within the context of the
nation's founding ideals. 

2276
02:11:20,560 --> 02:11:22,960
He reminded the audience that 
the soldiers had given their 

2277
02:11:22,960 --> 02:11:26,760
lives so that government of the 
people, by the people for the 

2278
02:11:26,760 --> 02:11:29,040
people shall not perish from the
earth. 

2279
02:11:29,760 --> 02:11:32,560
Lincoln's Gettysburg Address was
met with a mixed reception at 

2280
02:11:32,560 --> 02:11:35,800
the time, with some viewing it 
as too brief and simplistic. 

2281
02:11:36,280 --> 02:11:39,320
However, history would elevate 
his words to the status of a 

2282
02:11:39,320 --> 02:11:42,200
national treasure. 
The address encapsulated the 

2283
02:11:42,200 --> 02:11:45,480
purpose of the war and the 
vision of a nation united not by

2284
02:11:45,480 --> 02:11:48,520
force, but by shared values and 
ideals. 

2285
02:11:49,680 --> 02:11:52,400
The legacy of the Battle of 
Gettysburg continued to shape 

2286
02:11:52,400 --> 02:11:56,040
the course of the Civil War. 
While the conflict raged on for 

2287
02:11:56,040 --> 02:11:58,960
nearly two more years, 
Gettysburg marked a critical 

2288
02:11:58,960 --> 02:12:01,480
turning point. 
It showed that the Union could 

2289
02:12:01,480 --> 02:12:04,240
resist the might of the 
Confederacy and that the resolve

2290
02:12:04,240 --> 02:12:05,960
of its people would not be 
broken. 

2291
02:12:06,600 --> 02:12:09,960
The war's conclusion in 1865 
brought an end to the fighting, 

2292
02:12:09,960 --> 02:12:12,640
but left the nation grappling 
with the wounds it had inflicted

2293
02:12:12,640 --> 02:12:15,560
upon itself. 
The fields of Gettysburg became 

2294
02:12:15,560 --> 02:12:18,480
a place of reflection and 
remembrance, a site where the 

2295
02:12:18,480 --> 02:12:22,160
cost of division was laid bare. 
Over the years, Gettysburg 

2296
02:12:22,160 --> 02:12:24,960
transformed from a battlefield 
to a place of education and 

2297
02:12:24,960 --> 02:12:27,440
pilgrimage. 
Monuments and markers were 

2298
02:12:27,440 --> 02:12:30,520
erected to honour the soldiers 
who had fought and died there, 

2299
02:12:30,840 --> 02:12:33,200
preserving their memory for 
future generations. 

2300
02:12:33,720 --> 02:12:36,320
Visitors from across the country
and around the world came to 

2301
02:12:36,320 --> 02:12:39,840
walk the hallowed ground, to 
reflect on the sacrifices made, 

2302
02:12:40,120 --> 02:12:41,920
and to ponder the lessons of 
history. 

2303
02:12:42,520 --> 02:12:45,720
Today, Gettysburg stands as a 
testament to the resilience of 

2304
02:12:45,720 --> 02:12:48,240
the human spirit and the 
enduring struggle for freedom 

2305
02:12:48,240 --> 02:12:51,040
and equality. 
It reminds us of the fragility 

2306
02:12:51,040 --> 02:12:53,880
of unity and the strength 
required to preserve it. 

2307
02:12:54,840 --> 02:12:58,280
The lessons of Gettysburg echo 
through time, challenging us to 

2308
02:12:58,280 --> 02:13:00,920
remember that the cost of 
division is far greater than the

2309
02:13:00,920 --> 02:13:02,400
effort required to come 
together. 

2310
02:13:03,360 --> 02:13:06,760
As you rest tonight, let the 
story of Gettysburg remind you 

2311
02:13:06,760 --> 02:13:09,520
of the courage and sacrifice of 
those who came before us. 

2312
02:13:10,440 --> 02:13:13,640
Imagine the quiet fields at 
dawn, the softer rustle of the 

2313
02:13:13,640 --> 02:13:16,760
wind, and the stillness that now
blankets a place once filled 

2314
02:13:16,760 --> 02:13:19,360
with chaos. 
Let the strength of their 

2315
02:13:19,360 --> 02:13:22,520
resolve bring you a sense of 
peace, and may their legacy 

2316
02:13:22,520 --> 02:13:24,840
inspire hope and understanding 
in your heart. 

2317
02:13:25,360 --> 02:13:28,320
The legacy of Gettysburg extends
far beyond the battlefield 

2318
02:13:28,320 --> 02:13:30,600
itself. 
It remains a cornerstone of 

2319
02:13:30,600 --> 02:13:33,840
American history, not only as 
the site of a pivotal clash 

2320
02:13:33,840 --> 02:13:36,800
during the Civil War, but also 
as a symbol of the nation's 

2321
02:13:36,800 --> 02:13:40,080
enduring struggle to reconcile 
its ideals with its realities. 

2322
02:13:40,680 --> 02:13:43,520
The battlefields and memorials 
at Gettysburg now stand as a 

2323
02:13:43,520 --> 02:13:46,520
reminder of the courage, 
sacrifice, and humanity 

2324
02:13:46,520 --> 02:13:49,640
displayed by those who fought 
there, as well as the immense 

2325
02:13:49,640 --> 02:13:53,240
costs of division and conflict. 
In the years following the Civil

2326
02:13:53,240 --> 02:13:56,240
War, Gettysburg became a focus 
for national healing. 

2327
02:13:56,880 --> 02:13:59,800
Veterans from both the Union and
the Confederacy returned to the 

2328
02:13:59,800 --> 02:14:02,960
site to honour their comrades 
and reflect on the events that 

2329
02:14:02,960 --> 02:14:06,120
had shaped their lives. 
These reunions, particularly 

2330
02:14:06,120 --> 02:14:08,600
those held on significant 
anniversaries of the battle, 

2331
02:14:09,000 --> 02:14:11,720
fostered a sense of 
reconciliation and shared 

2332
02:14:11,720 --> 02:14:14,680
purpose. 
Despite the lingering wounds of 

2333
02:14:14,680 --> 02:14:17,440
war, these gatherings 
underscored a shared humanity 

2334
02:14:17,720 --> 02:14:20,000
that transcended the divisions 
of the past. 

2335
02:14:20,640 --> 02:14:23,520
One of the most moving examples 
of this came during the 50th 

2336
02:14:23,520 --> 02:14:25,640
anniversary of the battle in 
1913. 

2337
02:14:26,240 --> 02:14:29,640
Veterans from both sides, now 
old men, came together to 

2338
02:14:29,640 --> 02:14:32,960
remember their shared history. 
The event culminated in a 

2339
02:14:32,960 --> 02:14:36,080
symbolic handshake across the 
Stonewall at the sight of 

2340
02:14:36,080 --> 02:14:39,200
Pickett's Charge, a powerful 
gesture that reflected the 

2341
02:14:39,200 --> 02:14:42,720
desire for unity and peace. 
These reunions were not without 

2342
02:14:42,720 --> 02:14:45,720
their complexities, but they 
marked an important step in the 

2343
02:14:45,720 --> 02:14:48,080
nation's journey toward healing 
and understanding. 

2344
02:14:49,200 --> 02:14:52,440
Over time, Gettysburg evolved 
into a place of education and 

2345
02:14:52,440 --> 02:14:55,560
reflection. 
The Gettysburg National Military

2346
02:14:55,560 --> 02:14:58,440
Park, established in the late 
19th century and further 

2347
02:14:58,440 --> 02:15:01,920
developed in the 20th, preserves
the battlefield and its many 

2348
02:15:01,920 --> 02:15:05,400
monuments, ensuring that future 
generations can walk the same 

2349
02:15:05,400 --> 02:15:07,120
paths and learn the same 
lessons. 

2350
02:15:07,680 --> 02:15:10,560
The park's museum and visitor 
centre provide context and 

2351
02:15:10,560 --> 02:15:13,520
insight into the events of the 
battle, offering a deeper 

2352
02:15:13,520 --> 02:15:15,720
understanding of its 
significance and the people who 

2353
02:15:15,720 --> 02:15:18,400
shaped it. 
The Gettysburg Address, too, 

2354
02:15:18,400 --> 02:15:21,080
continues to resonate as a 
defining moment in American 

2355
02:15:21,080 --> 02:15:24,000
history. 
Lincoln's words, spoken with 

2356
02:15:24,000 --> 02:15:27,720
such clarity and purpose, serve 
as a reminder of the ideals upon

2357
02:15:27,720 --> 02:15:29,480
which the United States was 
founded. 

2358
02:15:30,080 --> 02:15:32,840
They challenge us to honour the 
sacrifices of those who fought 

2359
02:15:32,840 --> 02:15:35,880
by striving to create a more 
just and equitable society. 

2360
02:15:36,400 --> 02:15:39,640
Today, Gettysburg stands as a 
living testament to the enduring

2361
02:15:39,640 --> 02:15:42,720
importance of history. 
It draws visitors from across 

2362
02:15:42,720 --> 02:15:45,920
the globe who come to honour the
past, reflect on the present, 

2363
02:15:45,920 --> 02:15:49,240
and consider the future. 
The battlefield, with its 

2364
02:15:49,240 --> 02:15:52,560
rolling hills, stone walls, and 
quiet woods, invites 

2365
02:15:52,560 --> 02:15:56,400
contemplation. 
Walking its paths, 1 cannot help

2366
02:15:56,400 --> 02:15:58,800
but feel a connection to the 
stories of those who stood 

2367
02:15:58,800 --> 02:16:01,960
there, to the bravery and 
determination that defined them,

2368
02:16:02,240 --> 02:16:04,080
and to the lessons they left 
behind. 

2369
02:16:05,080 --> 02:16:08,040
The Battle of Gettysburg teaches
us that even in the darkest 

2370
02:16:08,040 --> 02:16:11,680
times, there is hope for 
redemption, for reconciliation, 

2371
02:16:11,920 --> 02:16:15,120
and for a brighter tomorrow. 
It reminds us of the cost of 

2372
02:16:15,120 --> 02:16:18,040
division and the strength 
required to build unity. 

2373
02:16:18,600 --> 02:16:21,320
It challenges us to live up to 
the ideals of liberty and 

2374
02:16:21,320 --> 02:16:24,240
equality, to honour the 
sacrifices of those who came 

2375
02:16:24,240 --> 02:16:26,640
before us by working to create a
better world. 

2376
02:16:27,600 --> 02:16:31,320
As you settle into rest tonight,
let the story of Gettysburg fill

2377
02:16:31,320 --> 02:16:34,799
your heart with a sense of 
reflection and gratitude. 

2378
02:16:35,520 --> 02:16:38,639
Picture the fields bathed in the
soft light of the setting sun, 

2379
02:16:39,000 --> 02:16:42,280
the gentle rustle of leaves in 
the breeze, and the quiet peace 

2380
02:16:42,280 --> 02:16:45,799
that now blankets the land. 
Let the echoes of courage and 

2381
02:16:45,799 --> 02:16:49,200
sacrifice guide your thoughts, 
and may their legacy inspire 

2382
02:16:49,200 --> 02:16:51,600
hope and understanding in your 
dreams. 

2383
02:16:52,480 --> 02:16:55,440
The story of Gettysburg is not 
only about the battle itself, 

2384
02:16:55,440 --> 02:16:57,680
but also about the enduring 
lessons it offers. 

2385
02:16:58,240 --> 02:17:01,799
It is a story of courage under 
fire, of ordinary people facing 

2386
02:17:01,799 --> 02:17:05,120
extraordinary challenges, and of
a nation striving to find its 

2387
02:17:05,120 --> 02:17:06,879
way through the darkness of 
conflict. 

2388
02:17:07,559 --> 02:17:10,400
Gettysburg reminds us that 
history is not just a series of 

2389
02:17:10,400 --> 02:17:14,680
dates and events, but a tapestry
of human experience woven with 

2390
02:17:14,680 --> 02:17:17,760
threads of sacrifice, 
resilience, and hope. 

2391
02:17:18,559 --> 02:17:21,799
As we reflect on Gettysburg, 
we're reminded of the power of 

2392
02:17:21,799 --> 02:17:24,040
unity and the dangers of 
division. 

2393
02:17:24,680 --> 02:17:27,600
The Civil War, of which 
Gettysburg was a turning point, 

2394
02:17:27,879 --> 02:17:31,240
was born out of deep seated 
disagreements and unresolved 

2395
02:17:31,240 --> 02:17:33,879
tensions. 
The soldiers who fought at 

2396
02:17:33,879 --> 02:17:36,760
Gettysburg came from different 
walks of life, different 

2397
02:17:36,760 --> 02:17:39,559
regions, and different 
perspectives, but they shared a 

2398
02:17:39,559 --> 02:17:42,600
common humanity. 
Their bravery and sacrifice 

2399
02:17:42,600 --> 02:17:45,799
speak to the strength of the 
human spirit, even in the face 

2400
02:17:45,799 --> 02:17:49,160
of unimaginable hardship. 
In the years following the 

2401
02:17:49,160 --> 02:17:52,120
battle, the memory of Gettysburg
became a source of inspiration 

2402
02:17:52,120 --> 02:17:55,799
for those working to rebuild and
reconcile A fractured nation. 

2403
02:17:56,400 --> 02:18:00,160
The scars of war ran deep, but 
so too did the determination to 

2404
02:18:00,160 --> 02:18:02,760
heal. 
Gettysburg became a symbol of 

2405
02:18:02,760 --> 02:18:05,280
what could be achieved when 
people came together to confront

2406
02:18:05,280 --> 02:18:08,520
their shared challenges and 
embrace their common humanity. 

2407
02:18:09,559 --> 02:18:12,200
The stories of the individuals 
who fought at Gettysburg add 

2408
02:18:12,200 --> 02:18:14,480
depth and texture to the history
of the battle. 

2409
02:18:15,080 --> 02:18:17,920
From generals like Robert E Lee 
and George Meade, whose 

2410
02:18:17,920 --> 02:18:20,920
decisions shaped the course of 
the conflict, to the rank and 

2411
02:18:20,920 --> 02:18:23,600
file soldiers who carried out 
those orders with bravery and 

2412
02:18:23,600 --> 02:18:25,959
resolve. 
Each story adds a layer of 

2413
02:18:25,959 --> 02:18:27,760
understanding to the larger 
narrative. 

2414
02:18:28,320 --> 02:18:31,600
These men, from both the Union 
and Confederate armies, faced 

2415
02:18:31,600 --> 02:18:34,600
unimaginable adversity with 
courage and dignity. 

2416
02:18:35,559 --> 02:18:38,240
One of the most enduring 
legacies of Gettysburg is its 

2417
02:18:38,280 --> 02:18:40,840
role in shaping the collective 
memory of the Civil War. 

2418
02:18:41,400 --> 02:18:45,080
The battlefield, now a serene 
and solemn place, serves as a 

2419
02:18:45,080 --> 02:18:48,120
reminder of the costs of war and
the value of peace. 

2420
02:18:48,719 --> 02:18:52,200
Monuments and markers dot the 
landscape, each telling a story 

2421
02:18:52,200 --> 02:18:54,639
of the men who fought and the 
sacrifices they made. 

2422
02:18:55,360 --> 02:18:58,320
Visitors to Gettysburg are often
struck by the quiet beauty of 

2423
02:18:58,320 --> 02:19:01,959
the place, a stark contrast to 
the violence that once engulfed 

2424
02:19:01,959 --> 02:19:04,080
it. 
The Gettysburg Address, 

2425
02:19:04,400 --> 02:19:07,160
delivered by President Lincoln 
just months after the battle, 

2426
02:19:07,440 --> 02:19:10,840
continues to resonate as a call 
to action and a statement of 

2427
02:19:10,840 --> 02:19:13,639
purpose. 
Lincoln's words remind us of the

2428
02:19:13,639 --> 02:19:16,799
importance of dedication, of 
recommitting ourselves to the 

2429
02:19:16,799 --> 02:19:18,639
principles of freedom and 
equality. 

2430
02:19:19,200 --> 02:19:22,320
His speech, though brief, 
captures the essence of what 

2431
02:19:22,320 --> 02:19:26,320
Gettysburg represents, not just 
a battle, but a turning point in

2432
02:19:26,320 --> 02:19:28,879
the ongoing struggle to create a
more perfect Union. 

2433
02:19:29,959 --> 02:19:33,040
Today, Gettysburg remains a 
place of pilgrimage for those 

2434
02:19:33,040 --> 02:19:35,639
seeking to understand the 
complexities of the past and 

2435
02:19:35,639 --> 02:19:39,360
draw inspiration for the future.
The stories of those who fought 

2436
02:19:39,360 --> 02:19:43,040
there, the lessons of unity and 
perseverance, and the enduring 

2437
02:19:43,040 --> 02:19:45,760
call to honour their sacrifices,
continue to guide us. 

2438
02:19:46,440 --> 02:19:48,440
Gettysburg is not just a place 
on a map. 

2439
02:19:48,920 --> 02:19:52,160
It is a symbol of resilience, a 
reminder of what we can achieve 

2440
02:19:52,160 --> 02:19:54,200
when we come together to face 
our challenges. 

2441
02:19:55,160 --> 02:19:58,000
As you drift off to sleep 
tonight, let the story of 

2442
02:19:58,000 --> 02:20:01,520
Gettysburg wrap around you like 
a warm blanket of reflection and

2443
02:20:01,520 --> 02:20:03,840
peace. 
Imagine the stillness of the 

2444
02:20:03,840 --> 02:20:07,600
battlefield at dawn, the quiet 
hum of nature reclaiming a place

2445
02:20:07,600 --> 02:20:11,400
once filled with chaos. 
Let the courage and sacrifice of

2446
02:20:11,400 --> 02:20:14,800
those who stood there inspire 
you, reminding you that even in 

2447
02:20:14,800 --> 02:20:17,160
the darkest times, there is 
light to be found. 

2448
02:20:17,760 --> 02:20:20,480
Thank you for spending this time
with us on history and sleep. 

2449
02:20:21,080 --> 02:20:23,840
May the story of Gettysburg 
bring you a sense of calm, 

2450
02:20:23,840 --> 02:20:27,480
perspective, and hope. 
Sleep well and may your dreams 

2451
02:20:27,480 --> 02:20:30,760
be filled with peace, 
understanding, and the enduring 

2452
02:20:30,760 --> 02:20:33,760
strength of the human spirit. 
Sweet dreams.