Kangaroo: Mighty Marsupials

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Speaker 1: Hi, I'm Appenney Money and I'm Rick Schwartz. Welcome to Amazing Wildlife, where we explore unique stories of wildlife from around the world and uncovered fascinating animal facts. This podcast is a production of I Heart Radio and San Diego Zoo Wildlife of Lions, an international nonprofit conservation organization behind the San Diego Zoo and Safari Park. Today's animal is a plant eating marsupial. You might think you know all about, but with fifty plus different species represented, I'm sure there are at least a few facts that may surprise you. We're talking about the kangaroo. Rick, It's surprising to learn that there are fifty different kangaroo species. In an earlier episode, we talked about the tree kangaroo, but there's also a red kangaroo, and the western kangaroo, and and so many more. Can you talk about the kangaroos that many of us think that we're more familiar with the ones that are that are more common, Well, Ebony, I do want to start off with offering a few more details to our listeners with regards to their being over fifty species. That number reflects the number of species found in the Macropotaday family. This is a scientific family of marsupials with similar skeletal structures and include species with the common name kangaroo, wallaby, wallaroo, tree kangaroos and more. Now, with that said, I think most people might be surprised to hear that there are three different species of kangaroo that make up the most abundant group of kangaroos in the macro PoTA day family. And often, because these three species look so similar, those who don't know the subtle differences assume they're all just one species of kangaroo. So let's hop into this. The three most abundant species of kangaroo are the eastern gray kangaroo, Western gray kangaroo, and the very famous red kangaroo. All together, these three species cover most of Australia and their population numbers are in the tens of millions. And one other side note, although their common name does have the color gray or red in it, their colorations can also look very similar regardless of which species they are. Wow, So let's reverse that question a bit. What are some of the lesser known species of kangaroos? Oh? I like, how you just pulled that one out of your pocket or should I say pouch? Al right, Just in case you are a new listener, this may surprise you, but there are species of kangaroos that live in trees. If you didn't know that, and then after you finished this episode, go back a couple of episodes and learn about the tree kangaroos, and that, of course leads us to the answer of your question, ebony the lesser known species of kangaroo tree kangaroos. Most people have never heard of such a species, much less ever seen one, and even those who live in areas where tree kangaroos live don't see them very often, sometimes referred to as the ghost of the rainforest. In fact, there's one species of tree kangaroos so rare it was thought to be extinct for almost a century. The Wanda Way tree kangaroo had not been seen since the late nineteen twenties, but in one was photographed in a remote New Guinea mountain range. I'd have to do more research, but I believe this place is the Wanda Way. As the all time champion of Hide and Seek, definitely in the running, not the winner. So how about the wallabies? Um, where does the wallaby fit? Is it? A different species of a kangaroo, or is it its own completely separate animal, or or are they cousins? Ah fair enough, epeny, I think we can jump into comparing and contrasting kangaroos and wallabies here. I mean to start off with the most obvious differences. Size. Kangaroos are much larger than wallabies. For example, red kangaroos can grow as tall as six feet in height and way close to two pounds now. The largest wallaby, on the other hand, is not much taller than two and a half feet and only ways in aroun forty forty five pounds now. Beyond the size difference, there are also some differences in tooth structure, but I don't recommend anyone who's not a veterinarian or wildlife care specialists try to look at their teeth to decide if it's a wallaby or kangaroo. And the other subtle differences beyond that are the structure behind legs. In general, if you saw a kangaroo and wallaby next to each other, you could see these comparisons a little easier. Kangaroos have more of a distance between their knee and ankle, giving them better leverage for moving rapidly across open habitat, whereas most wallaby species tend to have a shorter, more condensed leg structure, allowing for better mobility and agility in uneven rocky habitats and forest habitats. And interestingly enough, of course, each of these are well adapted for the habitats they live in. And that's all the more reason to visit the San Diego Zoo or San Diego Zoo Safari Park because honestly, these types of differences don't translate in pictures. I wouldn't have known that there was such a big size difference. Yeah, and it's kind of cool when you do go to walk about Australia the Safari Park, they do have shared space with kangaroos and wallabyes, so you can actually see the inferences. So when you think about kangaroos, many of us think of Australia, but are all species of kangaroos endemic to the land down under. Well, I believe there's a good reason why we think of Australia when we think of kangaroos. Terrestrial kangaroos like the reds and grays we were talking about, they are, as you said, endemic or native only to Australia and a few of the surrounding islands. In fact, you'll even find kangaroos on the coat of arms for Western Australia and on many coins of the Australian currency. And within the culture of Australia you'll find many sculptures, songs, books, and so much more with the kangaroo at the center of it all. Well, it makes sense that kangaroos in Australia go hand in hand. So speaking of things that you think of when you think of kangaroos, the second thing that comes to mind for me is their pouch. Is that a feature that is needed to be considered a kangaroo? Do kangaroos need that front pouch? Oh? Yeah, they absolutely do need a pouch, Ebony. Do you know not all kangaroos have pouches? No? I didn't, so, so wait, you just said kangaroos knee pouches, but not all of them have pouches. So how does that work? Well, Ebony, Um, that was kind of my goal is to kind of throw a little confusion there because I want to draw attention to this very important fact about all marsupials are you ready, ready? Okay, here it is not all marsupials have pouches. You see, only the females have pouches, not the males. So all our supials that are alive today are here because they were raised in a pouch. That's because when marsupials, including kangaroos, are born, they are very underdeveloped and need the protection of the pouch, where they also nurse on mother's milk to finish developing. So the lesson is to be on our supio means you were raised in a pouch, not that you have one. Now it all makes complete sense. At first I was a bit confused, but now I get it. Another reason why kangaroos are so well known because like our friend from episode forty, the Tasmania and Devil, kangaroos are very popular and even depicted in things like cartoons. Their images used to market products and sports teams. But how much do we really know about kangaroos? Rick, Can you help us we through some of the perceptions or or misconceptions about kangaroos to help us determine what's really true. Well, I'm sure I'm ready to jump in if you are, Ebony, I'm ready all right. I think one of the biggest ones and sort of perceptions around kangaroos is boxing. For whatever reason, people got it in their head that kangaroos box. Now, it might come from when males are sparring with each other for dominance over the mob or group. What they'll do is they will square off and they do reach out with their forelimbs or their front legs to measure the distance between them and their opponent. They may even grapple a little bit or grab onto each other with those forelimbs, but they aren't truly taking a swing like a box or punching. What they're really measuring for is when they're at the right distance and at the right time, they'll rear up on their tail and kick with their powerful back legs into the stomach of their opponent. So it's not really boxing. It's more of a kickboxing I guess. Well, thanks for clearing that up. I'm sure many of us have seen some of those images. Kangaroos are often depicted hopping around. Is this accurate? What's the kangaroo's primary method of mobility? Well, yes, Evany, I think it's fair to say that for most kangaroo species, hopping around is a primary method of movement. Kangaroos have impressive body adaptations that really allow them to maximize the efficiency of hopping, such as enlarged hind feet, powerful leg muscles, and a strong tail to help them hop. And I know what kind of sounds odd to think that a tail would help them hop, But get this, Although the kangaroos spine is in a more I don't know, I guess you'd say vertical position when standing. When they hop, the head lowers and the spine tends to be closer to a horizontal position. The tail than acts as a counterbalance to the upper body while the head and fore limbs are forward this position and allows for more efficient hopping. Without that big tail, they would not be able to move into that position and their hops would not be nearly as efficient. And to give you an idea of how well these adaptations work for the kangaroos, red and great kangaroos can hop ten ft vertically as in straight up, and when traveling at full speed about thirty miles an hour, they usually cover a distance of thirty five feet between each hop. And you mentioned that the strong tail helps them hop. I've heard it described as like a fifth leg. Is that accurate? Well, I mean yeah, I guess you could say that, because not only does the kangaroo's tail help it balance its body when hopping at high speeds, the tail is also kind of used as a kickstand when they lean back on it or when they stand to get the tall in their toes to get a better view. And like I mentioned before, males will lean back on that muscular tail to deliver those powerful kicks from the hind legs to fight for dominance. And here's a fun fact for everyone. Kangaroos can not move their hind legs independently like you and I can. You know we can step forward left foot, right foot. They have to move their back feet at the same time no matter what speed they're going. So even when they're just kind of browsing on grass and leaves or doing little movements forward, it requires a back feet to move at the same time. But instead of making little mini hoops, they simply reach forward with their front limbs, lift their hind end with their tail, and move the back legs forward at that time. So you mentioned that males fight for dominance with kicks and not punches, but are they considered aggressive animals. Are they aggressive towards humans overall? In general? The answer to that is no. Like most species, they tend to avoid conflict when possible and would rather leave humans alone. But that said, like in the animal, if they feel threatened, cornered, or endangered, they will do what they feel is necessary to defend themselves. And in that case, yes, kangaroos can be really dangerous. They pack quite a punch of you will, or in this case, a kick. And there are pictures online circulating of buff kangaroos with smaller front arms compared to their hind legs, and other pictures depicting these really, really muscular kangaroos as you mentioned, that almost look unbelievable. Which species of kangaroos are particularly muscular? Ah? Yes, the Internet memes influencing our education. As much as I'd like to say this is a myth that we can just bust, it isn't completely bustable. Although some images of really muscular kangaroos may be enhanced with photo editing software, the truth is they are very muscular animals. In fact, of the terrestrial kangaroo's body mass is muscle, and when it comes to attracting a mate. Well, female kangaroos fancy a mate with visible muscles. Males will fight in a way that looks like boxing like we mentioned before, more appropriately kickboxing, and the bigger and stronger male usually wins. And get this, it has been documented that when these males win, they will flex their muscles to gain attention from the females. And that's because female kangaroos are attracted to more muscular male kangaroos. And all this means is that the bigger muscular boys get to pass their genetics onto their offspring, increasing the odds of more muscular kangaroos in the future. That's funny that they will actually like flex their muscles for for females. Yep, it's not just humans that do that, not just humans. So kangaroos are described as social animals. What does that mean? What can you tell us about the structure of the kangaroo mobs? Oh? I really love talking about kangaroos social structures evening because it's kind of similar to a species of herbivore we have here in the US. And by the way, nice job using the proper term for a group of kangaroos. A side note here, a mob of kangaroos can also be called a troop or court of kangaroos, depending upon which culture you're talking to. Now, these mobs can have just a few individuals, or a mob can reach numbers close to an individuals. And these mobs are mostly made up of females and their offspring and just a few males. And as we mentioned before, males fight for dominance to basically lead or be in charge of the mob. Once they settle on who's the most dominant male, he leads the group and is the one who mates with all the females, well all of the females. Okay, so wait, you can't just say they're kind of similar to a species of herbivores here in the US and not tell us what you're referring to. What do you mean by that? Ah, yes, sorry about that. It's the deer that we have here in the US. It's really interesting how many parallels you can draw between the deer that we have here in the United States and the kangaroos in Australia. Both species are herbivores that have found ways to live in a variety of different climates and ecosystems. They have very similar social dynamics, and the deer herd functions much like the kangaroo mobs with females offsprings and the dominant male in charge of the group. It's in the further you look into it. It's really fascinating. It is fascinating. That's what's the fun about talking to you, because I would have never connected the deer and the kangaroo. Well, there you go. So the terrestrial kangaroos that we've been mostly talking about today sound like they're doing pretty well in the wild with their large mobs that are similar to herds of deer. But when we were talking about the tree kangaroos just a few episodes ago, many of those species are endangered. So what's causing this discrepancy? What causes some species of kangaroos to be endangered while others seem to be thriving. That is a really good observation, ebony, and it does make you wonder how or why that is happening, And like many situations, it is a complex answer. But in an effort to make this episode shorter than an hour long, I'll try to give sort of the big picture explanation, so the larger terrestrial kangaroo populations were kept in balance when they have their natural predator, the Tasmanian tiger. These medium dog sized carnivore marsupials were found in a wide variety of habitats across Tasmania, New Any and Australia. Unfortunately, they were hunted into extinction, with the last known living individual passing away in Nix. With the removal of the main predator, read and great kangaroo populations grew and grew, and continued to do so today. Now on the other side of the population spectrum, we have several species of tree kangaroos that have experienced population to clients, with many being listed as endangered species. They live in habitats that have experienced drastic changes from mining to deforestation and unfortunately, illegal hunting of many tree kangaroo species further impacts the declining populations. But likely mentioned in our tree kangaroo episode, there is a lot of work being done across several nations to support the conservation of tree kangaroos and their native habitats, so there is hope for them as we move forward. Coming up, we'll answer some questions from a young listener. But first this now it's time for the San Diego Zoom Minute, an opportunity for you to learn what's new at the zoo. People continue to enjoy the new Denny Stanford Wildlife Explorers Base Camp at the San Diego Zoo, which is home to four unique habitats and ecosystems. Explorers of all ages are able to see animals from each ecosystem, including a coconut crab, a prehensile tailed porcupine, an awesome lot tamandua, Cayman's Bennick, foxes, scorpions, and so much more. Did you know Tree kangaroos are the only kangaroos that can move their back legs independently of one another and move backward, which is how they climbed down a tree. Our young listener, Zion, wants to know why do kangaroos have big eels like jack rabbits? Hey, Zion, thanks for taking the time to send in some questions, and I really like the comparison you just made between the kangaroos ears and the jack rabbit. Like jack rabbits, the kangaroo is a prey animal or an animal that is hunted by other animals, and because they usually have their head down when they are feeding on grasses or low shrubs, they can't always see if a predator is around. But with those big tall ears they can rotate around independently. They can listen for any predator that might be trying to sneak up on them, no matter what position their head is in. You kangaroos sleep standing up, ordy, lay down? You know what, Zion. I don't think I have ever been asked that before, but I do think the way animals sleep is very interesting. And in the case of the kangaroo, they usually sleep laying down. But I say usually because I have seen them nap or doze off at times while standing upright. Oh and worth noting to tree kangaroos, which we've talked about in the past. They will sleep tucked up in a crook of a tree instead of laying on the ground. Why do kangaroos hop around so much? Hm, you know what, Zion, I'd have to say they hop around because they have to. I know that sounds kind of silly, but believe it or not, the way the kangaroo's bodies are structured, specifically, the muscles and tendons in the hip area. Their back legs cannot move independently like humans can, so even when they are moving slowly, those back legs move at the same time. Oh and here's another fun fact about their hopping. Although it takes you and I more energy to hop around instead of walk, because of that structure we talked about earlier in their hips, it's more energy efficient for the kangaroos to hop instead of trying to step. It acts almost like a spring which propels them forward, requiring them to use less energy. Can people have kangaroos as pets? Oh, Zion, I'm really glad you asked that, because I think a lot of people really love wild animals and think it would be fun to have these animals as pets. But like other wildlife, kangaroos do not make good pets. They require a special care, a unique diet, and behave much differently than a domestic dog or cat. And adult kangaroos are very strong, so even if they're just playing with us, they have the potential to really hurt us. Honestly, the best kind of pet is one you rescue from your local shelter. Domestic dogs and cats have been bred for thousands of years to live with people, and I can tell you from my own experience, a rescued pet is the best pet Zion. I want to thank you for taking the time to send in your questions about kangaroos. One of the best ways we get to learn more about wildlife is to always be curious and ask questions. And if any of our other young listeners have questions about wild life, please send us an audio file of you asking your questions to wildlife at i heeart Media dot com. Then keep listening to see if we answer your questions in an upcoming episode. Thanks for listening. We hope you've enjoyed learning more about the kangaroo and be sure to subscribe and tune into next week's episode and which will bring you the story of how we learned so much about chimpanzee's social behavior and who recorded these amazing observations in the wild. I'm any Money and I'm Rich Schwartz. Thanks for listening. If you would like to find out more about San Diego Zoo wildlaf Alliance, please visit sdz w A dot org. Amazing Wildlife as a production of I Heart Radio. Our producer is Nikia Swinton and Our executive producer is Marci de Peanut. Our audio engineer and editor is Sierra Spreing. For more shows from my Heart Radio, check out the I Heart Radio app, Apple podcast, or wherever you listen to your favorite shows.