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Okay, I've been waiting to feature this animal for a long time. The naked mole rat does not make an appearance in any of my novels (at least not yet), but I am simply fascinated by this creature. What is your concept of beauty? I don't mean physical beauty of people, which is greatly over-emphasized in pop culture. I'm talking about beauty in nature. Some people might think beauty is tall, snow-covered mountains. Others might think it's a wide open, undisturbed grassland, or an ancient forest. Or perhaps an animal, like a zebra or a bird of paradise. Well, beauty doesn't have to be physical (I'm not sure anyone would say these creatures are physically beautiful). But beauty can also be in the astounding adaptations of an animal or plant. Or in a bacterium, protozoan, or fungus, for that matter. It's the amazing adaptations and behaviors that make the naked mole rat a creature of beauty. What the heck is a Naked Mole Rat? One could argue that naked mole rats are the strangest mammals on Earth. But that's a matter of opinion, right? Let's look at them more closely so you can decide for yourself. Naked mole rats are not moles, nor are they rats. They are burrowing rodents that live in East Africa. This in itself is not unusual. After all, there are plenty of burrowing rodents, such as gophers, kangaroo rats, prairie dogs, and woodchucks. But... naked mole rats are unique in a number of ways. The most striking is their social structure. Naked mole rats (and one other species of mole rat) are the ONLY mammal species that are eusocial. This is a type of social structure in which the adults live in groups and work together to care for the young, and only certain females (queens) are allowed to give birth. If you're thinking that's the way some ants, termites, bees, and wasps live, you're right. Those insects are eusocial. But there are no other mammals that are eusocial.  Amazing facts about Naked Mole Rats Let's talk more about this eusocial thing. Hold on to your socks, because these amazing facts will just about knock them off! These creatures live in underground colonies, and when the queen dies, the dominant females basically start a war in order to choose which one will have the honor of being the new queen. As an example of how brutal this is, a captive colony of naked mole rats at the Smithsonian National Zoo needed a new queen, and during the selection process the number of adults was reduced from 17 to 13. The winning female in this case weighed 81 grams, while the closest competitor weighed only 55 grams. I guess size does matter. Once a female becomes a queen, she starts having litters right away. Her first litter may have as few as two or three pups (each weighing less than a penny). But she'll get pregnant over and over, and each pregnancy will stretch her spine out a little more (seriously) until she can have room inside for up to 28 pups!  By the way, naked mole rats sleep in big, writhing piles (to help keep warm). That's why the pups in the photo above are piled with adults. One of those adults is the queen, the only one that will suckle the pups. So, the queen nurses the pups until they are ready for solid food. At that point, the other adults in the colony take over care of the pups. They do this by feeding their poop to the pups! Yep, that's right. The adults produce a special kind of poop called cecotrope. This stuff is in the form of solid, yummy pellets that are full of good nutrients, as well as bacteria that the pups need in their guts to help them digest food as they grow older. Check out this video on Naked Mole Rats Let's take a look at the different roles in a naked mole rat colony. As stated above, there is one queen. And only one to three males reproduce with the queen. The other adults are called workers, and they are all sterile. The smaller workers typically gather food and take care of the nest. The larger workers are kind of like soldiers... if the burrow is attacked (by a snake looking for a snack, for example), these larger workers will defend the nest. In fact, they have been seen piling up at the entrance to block a snake from getting to the queen. This means that some of these soldiers might get eaten, thus sacrificing themselves for the queen. Wow. All the workers, no matter their size, work together to take care of the pups. As mentioned, other non-queen females in the colony are sterile. Amazingly, if the queen dies or is removed, some of the other females start producing certain hormones that make them fertile. And then they fight each other to become the queen. It is thought that the queen somehow suppresses fertility in all the other females in the colony. Again, wow! Below is a pregnant queen:  Here's another way mole rats are different from ALL other mammals: They are ectothermic. That means they are essentially cold-blooded. They do not produce heat internally, like other mammals do. Instead of regulating their temperature internally, they regulate it by changing their behavior. To stay warm, they sleep in restless, always-moving piles of mole rats. When they're hot, they move down to the deeper levels of the burrow, and when they're cold, they move up closer to the surface, which is warmed by the sun. Naked mole rats are extremely well adapted to the low-oxygen environment of their burrows. They can go without any oxygen at all for 18 minutes with no negative effects! And they can carry on with their normal activities for five hours breathing air that has only 5% oxygen (the normal oxygen level of the atmosphere of Earth is just under 21%). Naked mole rats, quite literally, feel no pain in their skin. This is because their skin lacks neurotransmitters. This is thought to be an adaptation to living in conditions with extremely high levels of carbon dioxide (they use up the oxygen in their burrows and end up breathing lots of CO2). When breathing high CO2 levels, acid builds up in the tissues, which normally would cause pain. Naked mole rats don't drink water. They get all the moisture they need from the food they eat (the underground parts of plants, like roots and tubers). A colony may include 75 to 80 individuals, and one colony's burrow system can include two to three miles (3-5 km) of tunnels. They dig these tunnels entirely with their teeth! Impressive, considering they don't even have dental insurance. Their lips seal closed behind their teeth, to keep the dirt out of their mouths. A whopping 25% of their muscle weight is the muscles involved with closing their mouths as they dig. If that were true for a human, our jaw muscles would be the size of all the muscles in one of our legs. Below is a photo of naked mole rats digging cooperatively. This is called a digging chain.  Naked mole rats live longer than any other rodents, up to 32 years! Most rodents this small (3 to 4 inches long, or 8 to 10 cm) live only a few years. Here's the weird thing about this: studies show that the mortality rate of these animals does NOT increase as they age. You may want to read that sentence again. They do NOT have more of a tendency to die as they grow older. In other words, they do not really age the way people do. They maintain a healthy heart and vascular system throughout their lives. And they are highly resistant to cancer. Pretty impressive, huh? I'll finish with a cartoon from Lindsey Leigh that kind of summarizes (in a humorous way) the life of a mole rat colony.  So, the Naked Mole Rat deserves a place in the C.A.H.O.F. (Copacetic Animal Hall of Fame). FUN FACT: The word copacetic is one of those rare words for which the origin is simply unknown. It is used almost exclusively in North America, and sources sometimes attribute it to Louisiana French, or to Italian, or even to Hebrew, among other possible origins. But the truth is, no one knows for sure. It's also unusual because it is not considered slang in its modern usage. The word means completely satisfactory, just fine, or excellent. So, copacetic is, more or less, another way to say awesome! Photo Credits:
Naked Mole Rat #1 - Meghan Murphy, Smithsonian’s National Zoo Naked Mole Rats with Pups - Liberty Science Center Pregnant Naked Mole Rat - The Japan Times Naked Mole Rat Digging Chain - Justin O’Riain via ResearchGate Naked Mole Rat Cartoon - Lindsey Leigh via ScienceFocus
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Typically, my novels include encounters with strange creatures. In my recently-released novel, INFINITY, the characters encounter coyotes. Now, if you live in the United States, you may think coyotes are not all that strange. However, the coyotes in INFINITY are unlike any coyotes you've ever seen (I won't give away any more detail than that). But you don't have to bridge to an alternate version of Earth to find amazing animals, because the coyotes we have right here on this world are pretty impressive. Let's find out more. What the heck is a Coyote? Coyotes are members of the canine family (Canidae). Which means they are related to dogs, wolves, foxes, dingoes, jackals, and others. Coyotes live in North America, and they are widespread in Canada, the U.S., Mexico, and even into Central America. Coyotes are medium-sized canines, smaller than wolves, larger than foxes. Typically, adults weigh between 15 and 44 pounds (7 to 20 kg). When you see one up close, you might assume it is heavier than that because of the bushy fur on its body and tail. The largest specimen ever recorded was a huge male killed in Wyoming in 1937, which weighed 75 pounds (34 kg).  Amazing facts about Coyotes All coyotes belong to the same species, but there are a whopping 19 subspecies, each of them unique in its own way. Among these subspecies are the northern coyote, plains coyote, mountain coyote, Mexican coyote, Belize coyote, and many more. A very diverse species! Coyotes are predators but will eat just about anything: rodents, rabbits, fish, frogs, snakes, insects, birds, and even grass and fruits. Studies show that mammals make up 90% of their diet. In fact, they are pretty impressive as predators when they hunt cooperatively to kill deer. Yep, coyotes are capable of killing adult deer, even though coyotes are MUCH smaller. The average size for a white-tailed deer buck is 150 to 300 pounds (68 to 136 kg). To accomplish this, coyotes hunt large prey in pairs or in small groups. Bringing down an adult deer, especially a buck, is dangerous, though, and usually younger, less experienced coyotes do not participate in this. Another dangerous prey animal is the porcupine, a large rodent with numerous sharp quills on its back. Many adult coyotes have learned to work in pairs to flip these rodents over and then attack the soft belly. This takes skill, and when younger coyotes try it, they often get a face full of needle-sharp quills.  But I think my favorite coyote hunting skill is their ability to pounce. They like to stand still and watch for rodents in the snow or grass. When they see one, they leap high into the air and come down on it from above. This technique tends to be highly effective, and therefore mice, rats, and voles make up a large part of a coyote's diet.  Humans have a love/hate relationship with coyotes, and the hate side often outweighs the love side. There are many reasons for this. Farmers and ranchers, for example, hate coyotes because these canines sometimes kill calves and other young livestock. Hunters hate them because coyotes kill deer, turkeys, geese, pheasants, and other game. Pet owners hate them because coyotes sometimes attack domestic dogs. These bad feelings toward coyotes have long been a part of North American attitudes, and coyotes are often portrayed in stories and cartoons as sneaky and devious. An example is Wile E. Coyote, the cartoon character who never gives up trying to catch the roadrunner, but always seems to fail in the most spectacular of ways. Check out this Wile E. Coyote video Coyotes are prolific. Females give birth to as many as 12 pups, and both the parents care for the pups, which results in a high survival rate of the entire litter. Research has shown that human attempts to curtail a coyote population often don't work because even if up to 75% of a coyote population is killed, these amazing creatures bounce right back to their previous level the next year. Since coyotes have few natural predators (besides humans), their populations are usually self-regulated by disease, or by the carrying capacity of their environment (the amount of food and space the environment offers). Coyotes are highly adaptable, and their range has expanded dramatically because of human activities. Before the 1800s, coyotes were mostly restricted to the southwest United States and in low numbers in the midwest. This was mainly because wolves prevented them from spreading. But humans have wiped out most of the wolves in North America, which opened up new territory for coyotes. By the 1970s, coyotes had spread across the continent, even far up into Canada. In fact, they even spread to the Canadian island of Newfoundland, presumably by swimming (coyotes are very good swimmers). Remarkably, some of the coyotes of Newfoundland are white! They're called snow coyotes:  There's an interesting story behind the snow coyote. A group of scientists recently studied some of these creatures by sequencing their genes. They found that each white coyote carries two copies of a specific gene related to hair color. The normal coyotes on Newfoundland have only one copy of this gene (which means the gene is recessive). Now here's where it gets interesting. Scientists have found this particular gene before—in golden retrievers. It's what makes the dogs have light-colored hairs. Here's my favorite part of the story: In Newfoundland in 2002, during the coyote breeding season, a male golden retriever ran off with a local coyote and never returned home. Did you know that coyotes often interbreed with wolves and domestic dogs? It's true. Hmm... so it's very possible that this golden retriever bred with the coyote, and they had puppies bearing the gene described above. Since the puppies only had one copy of the gene, they would have been normal in color. But after a few generations, some of these one-copy offspring probably interbred and produced two-copy offspring... and in this case the genes created nearly-white fur instead of the blonde fur seen in golden retrievers. I just love that kind of story! Okay, one more tidbit about coyotes. As stated above, coyotes are adaptable. In fact, they have learned to thrive in human-influenced environments. Coyotes are now becoming common in city suburbs and even in the centers of large cities. For example, only five miles from Chicago O'Hare International Airport, scientists have discovered the smallest known coyote territory ever observed. For at least six years, a coyote community has lived within about a third of a square mile. That must mean that the creatures are finding it very easy to locate plenty of food and water right there in that tiny urban area. Again, people have mixed feelings about urban and suburban coyotes. What do you think? Should we try to wipe out these new city dwellers, or should we just accept them as another part of the urban landscape, like the pigeons and feral cats?  So, the Coyote deserves a place in the T.A.H.O.F. (Tubular Animal Hall of Fame). FUN FACT: Dude, you know where tubular comes from, right? Well, let's start at the beginning. The word actually originated in the late 1600s, and it meant "having the form or shape of a tube." But in the late 1970s, surfers started using the word to describe when waves break like a barrel. With the help of the Frank Zappa song "Valley Girl," written and sung by his daughter Moon Unit, the word began to be used widely to mean something "cool" or "excellent." Now the word is pretty much just used as a way of mocking the 1980s. Nevertheless, tubular is another way to say awesome! Photo Credits:
Coyote in snow - Yathin S Krishnappa via constantinealexander.net Coyote with porcupine quills - Nicerweb Coyote pouncing on rodent - Justin Jensen via Flicker Snow Coyote - Michael Blackwood via National Geographic Urban coyote - Matt Knoth/Shutterstock via Mother Nature Network |
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