Naked Mole-Rats: Baring It All

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Speaker 1: Hi, I'm happening 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 Alliance, in international nonprofit conservation organization which oversees the San Diego Zoo and San Diego Zoo Safari Park. Now I'm pretty excited because today we're featuring a very special species. It's a hairless pink rodent with wrinkly skin. I'm talking about the naked mole rat. And now, anybody out there that might have grown up watching Disney Channel before we had all these streaming services, you might remember the show Kim Possible. Kim Possible was very popular and her friend had a pet loll rat named Rufus. So that's the same species we're talking about. But I think you're gonna learn in the species that Rufus living on his own as a sidekick to a superhero wasn't exactly how naked mole rats lived their life. They're more closely related to porcupines and guinea pigs and they live underground. Now we're going to talk about what they have in common with honeybees and all the other facts that make them so unique. Will also hear from a young listener to find out what she'd like to know about mole rats. Now, Rick, before we jump in, I need to offer an advanced apology. Apparently naked is just one of those words that I just tend to say funny, but I will concentrate to make sure I get it right, because I know the naked mole rat is a favorite for so many people, Like who knew a rodent could be so popular? I recently read an article exploring the unlikely stardom of the neked molerat. Apparently there's children's books, naked mole rat cam and all sorts of excitement around this species. Who I knew? Actually, because it's it's really pretty awesome. I love how interested people are in these underground tunnel living rodents. They're truly fascinating to me. And I love that we are digging in to all things naked molerats today because one of the very first species I got to work with when I started at the San Diegoes over twenty years ago wasn't naked mole rat colony, And I can tell you this, people were always so curious about them. You know, I think just talking about it, saying there type of road and it's like, okay, well it's a rodent. But when you see them in person, they are truly fascinating to watch, and people were always asking questions and spending a lot of time just observing them right at their habitat. So, Rick, what do you think is at the root of all this interest? Oh, ebony, tell me that pun was on purpose? The root part right at the roots. Yes, they survive off of roots and tupers. I I this is a great pun, whether you did it on purpose or not. But back to your question, So, why are people so interested in them? Well, I can tell you from my experience it's because they look so different from any animal we normally see. And I want to warn our listeners right now if you decide to do a Google search to see one for yourself, it's going to be something you will never forget. But I also think the looks of the naked mole rat are are just it's hook. Honestly. You know, if a good story has a good hook to draw you in, their looks are that hook. Once people start to learn more about them, their unique social structure that we don't normally see in mammals, the vast size of their colonies that they live in, how they defend themselves against predators, and so much more. You you just can't stop wanting to learn more about them. Well, I can't wait. Let's start from the beginning. What exactly is a naked mole rat? Good idea. Let's start with what exactly is a naked mole rat? Well? First, they are native to East African countries of Somalia, Ethiopia, and Kenya. Naked morats are rodents that are bigger than a mouse put smaller than a rat. They do have a few thin hairs. They aren't truly completely hairless, but you can only usually see those if you are up close for the most part, so at a glance or at a distance, they do look hairless with a light pink, sometimes grayish colored skin. And now, the word mole and rat are part of their common name. But sometimes common names of animals can be misleading, and our friend, the naked mole rat is a great example of that, because they are neither a mole or a rat. In fact, the way the family of rodents breaks up. They're more closely related to the African porcupine and guinea pigs. And to be totally honest, you alluded to this just a bit ago, but these species are quite interesting looking, um I would say unique. Can you describe some of its other standout features? Well, let me let me turn this around on you a little bit. It's always trying to kind of have this back and forth, so let me ask you have any aside from looking like they were, you know, hairless completely, what is the first thing that stood out to you when you saw a naked molerat Those two front teeth, because they literally stick out right. Okay, well, well those are hard to miss and they are so important for the more rat so and for a good reason that that's something that people notice right away. Not only are they just you know, teeth in general are important for any mammal, of course, but the front teeth, the incisors for the naked morat, are very important tool for them. But before we go completely into the importance of how those teeth are used, it's worth mentioning they're incredibly noticeable, not just because of their size, but these front and sizers are actually growing outside of the mouth, so with their mouth clothes you can still see them, and not because they're sticking out of a lip, but they literally grow outside the mouth. And like all rodents, these front and sizers never stop growing, so they're great tools. They'll never go away, they'd never wear down. Now, why are these teeth so important for the naked morat. Well, often we think of teeth they're for biting and for chewing food, But for the naked more rats, the front and sizers are the tool they use for digging. Now it's really fascinating because many other rodents who also tunnels or burrows, use their front feet for the actual digging, the back feet and push the dirt for their way for excavating. But for naked morats, their mouth is structured so they can use their front and sizers as a digging tool. And get this, if they're digging upwards, which means looser would be falling down towards your mouth, the structure of the jaw and the way the mouth works with the conjunction of the teeth, the mouth and throat are closed off as they dig, so no dirt goes in their mouth. Then it's also worth mentioning too. I mean, while we're on the topic here, the teeth are very important for defending themselves. The jaws are very very powerful. As you can imagine, they're always digging through dirt using their jaws, which is then, of course, very helpful when it comes to defending yourself from a predator. If a predator comes down into the tunnels, well naked morats will use those large teeth and powerful jaws to defend themselves and they're usually very effective. And you mentioned that naked mole rats are native to Ethiopia, Somalia, and Kenya. What kind of habitat do they live in? You mentioned dirt? They live in dark, vast underground tunnels. I mean it sounds kind of spooky and intriguing. It is kind of cool, actually, But they dig these tunnels in the savannahs, shrub lands and grasslands, even caves of those East African countries we mentioned. Now this is known as a subterranean habitat, meaning they live in tunnels and burrows that they make. And one of more things, I want to give everyone a very fun word that they can use with words with friends or scrabble, maybe even the next time they play a trivia game, it's fossorial. So what does that mean? Foss oil which, again for our words with friends players and scrabble players, that's f O S s O r I A l. Is a zoological term that means adapted for burrowing. More specifically, the animal has an adaptation on their body that specifically helps them with burrowing and living some or in the case of morats, most of their life underground. And as we discussed earlier, for the naked morats, their teeth are a great example of that adaptation for burrowing. So let's talk a bit about mole rats senses. From what I understand, are they somewhat blind or fully blind? Well, yes and no, so they aren't completely blind. If you were to see a picture of it, again, I warn people carefully before they go google that, but if you were to see a naked mole rats face, you would see that their eyes kind of looks like two tiny dots on their face. It's believed that their eyes can sense changes in light and dark, but don't have the proper sense of sight. Beyond that. That being said, it kind of makes sense since they don't need to really rely on their eyesight because they live in dark tunnels underground. But what they lack in sight, well they make up in their sense of smell and touch. And although they have small ears which is like little bumps, really, they do have a sensitivity to sound in vibrations as well and ric something also really unique about the species, the mole rats social structure. What is a queen rats? The queen rats? You know, ebody. I find myself saying the sentence over and over again when it comes to naked morats. But this is one of the more fascinating things about the naked mole rat. I swear, I don't I feel I say it a lot, but this is this is pretty cool. Hang with me here, okay. Naked morats are one of only two mammal species that we know of that live in what's called a youth social colony or youth social structure. And that's spelled e U S O C I A L. For those of you doing scrabble words with friends or if you're doing some trivia and now you have another one also this is this episode is chalk full of fun facts for everyone. The other species of mammal is closely related to the naked mole rat, known as the dharma land or damarrow mole rat. Now as rare as this is in mammals, This youth social structure is what basically termites and bees are well known for. So essentially that means the naked mole rats live in a cooperative group with one female called the queen and a few males that are reproductively active with her. The rest of the colony is made up of non breeding individuals that are tasked with caring for the young, maintaining the tunnels, protecting the colony, harvesting and maintaining food sources for the colony, and so on and so on. And keep in mind these colonies can be pretty big, with anywhere from twenty to three hundred individuals, and with those bigger colonies, their tunnel system can cover as much area as six football fields. Wow, and Rick, The yucky truth is that mole rats within these colonies eat their own waste. What's the purpose? Well, okay, now, to be fair, naked mole rats are not the only species to do this, and when I explain the reason why they do this, hopefully it will seem a little less yucky, or at least make sense as to why they do this. Okay, So the naked mole rats rely on roots and tubers for their main source of food and these can be very hard to digest. These These aren't, you know, gushing with juice. These can be very dry, dense fibrous materials. To help the naked morat digest this fiber, their intestines are full of microscopic organisms to help with breaking down the nutrients. But these microscopic organisms do leave the body of the naked mole rat through their waist, so to assist in maintaining these digestive organisms in their system, naked mole rats will eat excrement that is high in microscopic organisms. And while we're on the topic of waste, here are some more fascinating facts. Naked mole rats have specific chambers throughout their tunnel system. They will have chambers for storing food, chambers for nesting, and chambers for waste. Members of the colony will go to the waist chamber and roll around in the feces there. Now, this gives everybody in the colony the same smell. This is very important for identification purposes and to keep in mind, they don't see very well, so if an intruder should come into the tunnels, they can immediately identify the intruder because they don't smell like everybody else. It seems kind of gross, but it's also a very effective way to keep the colony safe. I should have known that it served a very useful purpose. So, Rick, something that you said earlier was very interesting. If we could go back to the subject of breeding, can you tell us more about the queen in the unique social structure. Yes, that social structure plays a big role in who gets to have babies in a naked mole rat colony. Remember when we were discussing the naked mole rat social structure. There's a queen who's in charging the colony, like you mentioned, and a small group of males are allowed to mate with her. That queen is the only female in the whole colony that breeds and raises the young. Now, what's important to understand is that a queen is not born into the position. Females have to fight for it, sometimes to the death, but of course the strongest survive, and then when she does well, she has the right to be queen. Now, once that fight is over and the queen is established, her body will actually go through physical change. It's almost like when other mammals go into maturity, sexual maturity. That's what's happening. Her spine grows, it gets longer, her public bone widens and gets thicker, all to allow her to be ready to have babies. In fact, she will have anywhere from twelve to twenty four pups at one time and give birth easily four to five times a year. That's amazing. So rick rodents are often considered by some people as something that needs to be eradicated. Mole rats are sometimes targeted because of that, and because of the damage that they can cause two crops. Overall, what are the obstacles that that morats face? Is it what I just described or or what else are they facing? A nature well, you know the answer, fair question. A lot of species were discussing that they do have some challenges, but for the most part, naked mole rats live in areas that do not have much farming or human development. But in areas where crops like sweet potatoes are being grown near the native habitat, they potentially could cause damage. Those are some pretty yummy you know tubers right there, those sweet potatoes. And if agriculture should expand further into the native range of the naked morat, they could become targeted as a pest like other rodents. Fortunately for the naked mole rats at this time, there are few obstacles and threats to them beyond their natural predators such as the snakes and African servo cats. That's good news for them. Um, when when it comes to conservation, what's the status of the naked morat? Well, have any I am happy to say when it comes to the conservation status for naked mole rats, it's all good news. Uh. They are currently listed as least concerned when it comes to the possibility of becoming endangered and we are very hopeful that it stays that way. Now it's time for the San Diego Zoo Wildlife Alliance minute an opportunity for you to learn what's new at the Zoo. One rodent we work with is the endangered San Bernardino kangaroo rat. In the fall, over a five week period, collaborating with our partners California Department of Fish and Wildlife, Riverside Conservation Authority, and San Bernardino Valley Water Conservation District, we moved individuals to a new site to expand the range of its population and to help them adjust to their new digs. The Riverside Conservation Authority made their new home site even more appealing by finding the shrubs and removing non native grasses. Once the kangaroo rats arrived, they fed them for about a week, tossing around seed all over the site. After about a month, they confirmed at thirty eight kangaroo rats were still living in the area. Our researchers will continue to supply supplemental food at the site in hopes that these individuals will make it through the winter. Today we've talked about naked mole rats and their unique array of behaviors. These hairless rodents have a cult following. People love learning about them. We have a few questions from a young listener, Acacia. Why don't naked mole rats have hair like other rodents? Acacia, That's a great question, especially because a lot of burrowing rodents like prairie dogs, ground squirrels, and golfers all have hair. When it comes to our friends, the naked mole rats, it's believed that their hair is simply not needed. This is because they have no connection at all to the surface above the ground. They don't need hair to protect them from the weather conditions or the sun. And because they basically create the perfect little micro climate in their tunnels with warm, moist air and the temperature is always perfect for them, basically there's no need for the insulation that a fur coat would offer. What kind of animals hunt naked morats and how do they defend themselves against predators? Well, remember accasion, naked morats spend all of their time underground, so their number one concern when it comes to predators is snakes. On occasion, when naked morats are pushing soil up to the surface, although they usually don't come all the way out of the tunnel when they do this, uh, they are close enough to the surface that an African servile, a type of wildcat with very long legs, can reach its paw down and grab a naked morat. And to answer the other part of your question, how do they defend themselves against predators? Well, if a snake should find itself in one of the naked mole rats tunnels, as soon as the naked morat senses the snake is there, instead of trying to run away from it, the naked morats that are part of the colonies. If you will security detail immediately rushed towards the snake, and just before coming face to face with the snake, they will get close together and squish themselves up on top of each other, sort of making a cork to block the tunnel, and then open their mouths as wide as they can. This creates a very dangerous naked mole rat cork right there in the tunnel with sharp, powerful teeth aimed right at the snake. If the snake tries to strike, there really isn't any way for the snake to get ahold of just one individual. And as soon as the naked morats start biting back, well, that snake most likely will change its mind about trying to find a meal and a naked morat tunnel. If naked morats live underground all the time, how do they breathe and where do they get their food and water from? I love the way you think. Many species that burrow leave their tunnels and dens to collect food or find water, And to think the naked morats never leave their tunnels, and their tunnels don't have an opening. How do they survive? We get this when it comes to breathing naked mole rats don't need the same amount of oxygen that you and I do to survive. Additional, they can survive in an environment with a much higher percentage of CEO two than most mammals. Just another great adaptation they have for living in a colony underground. Now, when it comes to food and water, they live primarily on roots and tubers they grow underground. From this food source, they also get all of the hydration they need, so there's no need to visit a watering pole. Oh and here's something I think that the niggaments to figure this out, and it's just brilliant. When they find a tuber which is a large route, basically they burrow into it, eating the inside but leaving the outer parts to continue to allow it to grow and therefore it becomes a sustainable food source. They are so smart. Occasia, I want to thank you for asking those very thoughtful questions. I really loved answering them. And if any of our other young listeners have an animal question or two or three, please send us an audio file of you asking your question to Wildlife at I heart media dot com. Then keep listening to see if we answer your questions in an upcoming episode. Thanks for listening. We hope you learned a lot about the interesting, surprisingly popular pink hairless mole rat. And remember you two can see neked mole rats at the new Wildlife Explorers base camp at the San Diego Zoo. Be sure to subscribe and tune into next week's episode, in which will bring to the story of some of the busiest pollinators on the planet and why they are so important to all of us. I'm Ebony Mone and I'm Rich Schwartz. Thanks for listening, and if you'd like to find out more about San Diego Zoo Wildlife Alliance, please visit sdz w a dot org. Amazing Wildlife. As a production of I Heart Radio. Our producer is Nikia Swinton, Our executive producer is Marcy de Pina. Our audio engineer and editor is Amina Gnatra. For more shows from My Heart Radio, check out the I Heart Radio app, Apple podcast, or wherever you listen to your favorite shows.