Category Archives: North America

Episode 484: The Sewellel and the Superflea

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The sewellel is a little rodent:

The superflea is a big flea (left, compared to a regular flea, right):

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Let’s learn about a rodent you may never have heard of, unless you live where it does, and a parasite that makes that rodent its host. It’s not an ordinary parasite, but don’t worry, it’s not icky. You can continue to snack.

The rodent is called the sewellel, Aplodontia rufa. It’s also called the mountain beaver even though it doesn’t always live in the mountains and it isn’t a beaver. It doesn’t even look like a beaver. For one thing, it only has a little nub of a tail and it only grows around 20 inches long, or 50 cm. It has small eyes and ears, short legs, a chunky body, and long claws. This body shape should give you a hint about its lifestyle: the sewellel is a digger, although it can also swim just fine and can even climb small trees to eat young twigs and leaves.

The sewellel is an aplodont, a large group of rodents that have been common in Europe, Asia, and North America for 40 million years. But it’s the only one left. All the other aplodonts went extinct several million years ago at least. We’ve actually talked before about one of the sewellel’s extinct relations, the horned gopher (which was not a gopher), in the Patreon episode about animals with nose horns.

The sewellel itself hasn’t been around all that long, only appearing in the fossil record a few million years ago. It lives in a small area of northwestern North America, in parts of British Columbia, Washington state, Oregon, and a few parts of California. It lives in forests where it doesn’t get too cold in the winter, since it doesn’t hibernate and isn’t as good at keeping itself warm as other rodents are. It also needs to drink more water than other rodents and prefers to live in wet climates as a result.

In fact, the sewellel is sometimes referred to as a living fossil since it lacks many features that all other living rodents have. Its teeth resemble a simpler version of squirrel teeth, so some researchers think it may be most closely related to squirrels, but even if that’s the case, it isn’t very closely related. The sewellel’s ancestors were more adapted to live in trees and a study published in 2018 determined that it had a larger brain than the sewellel. Since the sewellel is nocturnal and spends most of its life underground, it doesn’t need to see very well, and the part of the brain that processes vision is much smaller than in its ancestors.

The sewellel mostly eats ferns, although it also eats other plants, and some of its favorite plants are toxic to other animals. It’s a solitary, mostly nocturnal animal that digs deep, complex burrows, and it stays as close as possible to the burrow entrance so it can hide easily if it needs to. Everything eats the sewellel, from owls to coyotes to bobcats to eagles.

And that brings us to the parasite associated with the sewellel. Many animals have parasites that are specific to that particular species. The Patreon episode about whale lice has some information about how specific this can get. The male sperm whale has a different species of louse than the species that lives on female sperm whales, for instance. Also, the whale louse isn’t a louse, it’s a type of crustacean.

The sewellel’s parasite is a type of flea. Big deal, you say, fleas are all about the same.

Are they, though? Because the sewellel’s flea is actually kind of a big deal. It is, in fact, the largest flea known, called the superflea. It can grow up to 8 mm long (and possibly longer, reports vary). I just measured, and that’s the length of my little fingernail, from the base to the quick. Most species of flea are 3 mm long at most.

The superflea is only found on the sewellel. It looks like an ordinary flea except for its size, meaning it’s laterally flattened with legs that allow it to jump long distances. So why is it so big compared to other fleas, especially considering that it lives on an animal that’s about the size of a chonky cat? No one knows. No one has even the slightest idea why this flea is so big.

There used to be even bigger fleas, some up to two cm long. That’s 20 mm, or just a little more than twice the length of the superflea. Of course, those 20 mm fleas lived 165 million years ago and probably lived on dinosaurs. Also, they couldn’t jump and instead of being flattened laterally, or side to side, like modern fleas, they were flattened dorsoventrally, or top to bottom. So they weren’t very much like modern fleas.

That’s all we know about the superflea, but let’s have one last sewellel fact before we go. With all this talk of the sewellel being a primitive rodent whose closest relations are all extinct, you might think there’s nothing really special about it beyond its giant fleas. You would be wrong, though, because the sewellel’s front paws have opposable thumbs. It’s not as mobile as our opposable thumbs, but it allows the sewellel to manipulate food more easily. It will sometimes sit up on its big round bottom to eat, just like a really weird squirrel.

Thanks for your support, and thanks for listening!

Episode 483: Animals with Nose Horns

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The horned gopher:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This time we’re going to learn about some mammals with weird horns. Specifically, weird nose horns. Nose horns are properly called rostral horns, but that’s not as funny.

We’ll start with a family of extinct rodents called horned gophers, or more properly, mylagaulids. The horned gopher wasn’t a gopher, but it probably looked similar to ground squirrels like prairie dogs and marmots. It lived in what is now North America around twenty million years ago, and it had a pair of short, broad horns that pointed upwards between the nose and eyes, like a rhino’s horns but side by side and made of bone, not keratin. It was big for a rodent, about a foot long, or 30 cm, and ate plants.

So what did the horned gopher use its horns for? Both males and females had the horns and they’re too short and placed too far back for males to use them to fight each other. Horned gophers had poor eyesight so males probably weren’t trying to look and act flashy to attract females anyway.

At first researchers thought the horns helped in digging burrows. The horned gopher primarily used what’s called the head-lift method of digging, which means it pushed its nose into the dirt, then lifted its head with powerful neck muscles to remove a chunk of soil—basically using its nose as a shovel. But its horns pointed straight up and were set too far back on the nose to help with digging. Most researchers today think the horns were used for defense. If a predator tried to grab the animal by the neck, it could snap its head back and stab the predator right in the face.

The horned gopher had tiny eyes and front feet that resembled a mole’s, with long claws. Researchers think its ancestors probably spent most of the time underground, but that as it evolved to become larger, it also spent more time foraging above-ground. That led to more predators being able to attack it, so evolving horns as a defensive weapon helped it survive.

While the horned gopher was distantly related to modern squirrels, its family is completely extinct these days. But it’s still the smallest known horned mammal that ever lived.

The horned gopher is also the only horned mammal known that lived mostly underground in burrows. Almost. There was once a type of armadillo, naturally called the horned armadillo but more properly referred to as Peltephilus [pelta-FEElus], that had a pair of horns over its eyes but a little in front of them, close to where the horned gopher’s horns were. The horned armadillo’s horns developed from scutes on its head, and if you remember, scutes are bony plates embedded in the skin as armor. It might also have had a smaller pair of horns over its nostrils. It lived in what is now South America and went extinct around 11 million years ago.

The horned armadillo dug burrows liked the horned gopher did, but it was much bigger than the horned gopher, with some species as much as five feet long, or 1.5 meters. Despite its size, it probably resembled the pink fairy armadillo in overall shape rather than the more common nine-banded armadillo that lives in parts of North America. It had a short tail and its rump was squared off instead of rounded. It also had big sharp teeth. It may have eaten insects, possibly digging up ant nests, but more likely it mostly ate roots and other plant parts.

Arsinoitherium was another animal with nose horns, this one from Africa. It lived around 30 million years ago and was related to modern-day elephants, but it lived in swampy areas and tropical rainforests and ate plants. It probably looked a little like a rhinoceros and a little like a small elephant without a trunk. Different species were different sizes, but they were all pretty big, probably no smaller than about six feet tall at the shoulder, or 1.75 meters. And they had two pairs of horns, a little pair more like bumps over the eyes and two side-by-side forward-pointing giant nose horns that looked a lot like rhino horns but thicker. But they were real horns made of bone, not keratin, although they may have been covered in skin and hair like ossicones. You know, ossicones are those hornlike structures giraffes have.

Brontotherium looked a lot like a rhinoceros too, but that’s because it was distantly related to the rhino, although it was more closely related to the horse. It lived in North America around 35 million years ago and was enormous, standing around 8 feet tall at the shoulder, or 2.5 meters. It was a selective browser, probably preferring tender leaves to tough grass. It carried its massive head low like modern rhinos and buffalo do, and had a humped shoulder like both those animals where its massive neck muscles attached. And it had a pair of nose horns.

Both males and females had the nose horns, but the males’ horns were much larger. The horns were blunt and shaped sort of like a V, and researchers are pretty sure males used them to fight each other. We have fossilized brontotherium rib bones that show an injury shaped just like the nose horns. The horns were probably also useful to fight predators. Even though brontotherium was related to the rhino, its horns were bone, not keratin.

Our last nose horn animal lived in North America up to about five million years ago. The various species of Protoceratidae [pro-TOSS-e-rated-die] were hoofed animals that looked sort of like deer, but were more closely related to a living ungulate called the chevrotain, or mouse deer. Protoceratid probably ate grass and other plants and may have lived in herds. Males had a pair of ordinary horns that looked a lot like cow horns, and in some species females had the horns too, although they were smaller. But males also had a horn on the nose. And it was weird.

Once again, the nose horn wasn’t like a rhino’s horn, which as we have established by now is made of keratin. And maybe I should have reminded you before now that keratin is the same protein that makes hair, fingernails, hooves, and things like that. Keratin also doesn’t fossilize. This nose horn was an actual horn made of bone, but researchers think it may have been covered with skin and fur like an ossicone.

Different Protoceratidae had different nose horns. Syndyoceras had a pair of nose horns that were fused at the base, then split apart to form a V shape. It may also have had large nasal passages that made its muzzle look much bigger than the skull would suggest at first glance. Synthetoceras had a long nose horn that grew up and slightly forward but split into a Y at the tip. Kyptoceras had a pair of nose horns that pointed forward. Researchers think the males used these nose horns to fight each other, much like deer fight with their antlers today.

One older Protoceratid that lived up to around 20 million years ago was called Protoceras, and males had three pairs of horns, although they probably resembled ossicones and were all covered in skin and hair. A small pair grew between the ears, another pair between the eyes and nose, and the largest pair grew on the nose. Females only had one smaller pair of horns between the ears, so the extra horns males had were probably for display.

Some Protoceratidae also had a pair of fanglike canine teeth that they may have used to root around in dead leaves for plant material. Male chevrotains have fangs like this too, but they use them to fight each other since they don’t have horns.

So basically, this is what we’ve learned from this episode: There used to be a lot more nose-horned animals than we have now, most of them lived in the Americas for some reason, and they were all awesome. Also, even though the first animal we think of when someone mentions nose horns is the rhino, the rhino’s keratin horns are actually unusual. Just be glad you’re not an intelligent birdlike creature from the far future trying to figure out what a rhinoceros actually looked like when it was alive.

Thanks for your support, and thanks for listening!

Episode 482: Smoky Mountain Mystery Animals

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I took this episode from an article I wrote for Flying Snake magazine, which was published in December 2020 (Vol. 6, #18).

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

The Great Smoky Mountains is a subrange of the Appalachian Mountains, which stretches from the middle of Alabama in the United States north into southeastern Canada. The Appalachians formed when the world’s continents crunched together to form the supercontinent Pangaea. The southern Appalachians formed separately and later than the northern Appalachians, around 270 million years ago.

The Appalachians were once as high as the Rockies or Himalayas, but by the time the dinosaurs went extinct, they had eroded down to the mountain cores. Sediment weathered from the peaks and filled in valleys. But during the Pleistocene, when massive glaciers covered the northern parts of North America, the weight of the ice pushed the North American plate down, causing the southern part of the plate to rise. Eventually the ancient mountains’ roots were a thousand feet (300 m) above sea level again. Rivers that once flowed east into the Atlantic Ocean or west into the remains of the shallow Western Interior Seaway shifted their courses to flow northward. Streams that once meandered across the land now plunged down steep slopes and dug gorges into the rock. And over thousands of years, animals and plants retreating from the ice migrated southward along the mountain range.

When the climate warmed some 11,000 years ago and the ice age glaciers melted, many cold-adapted species were trapped in the peaks of the southern Appalachians. One of the highest peaks is Mount LeConte, with its highest point, High Top, measured at 6,593 ft, or 2,010 meters. I hiked Mount LeConte on 7 May, 2016 when the weather in nearby Knoxville, Tennessee was a warm 82 Fahrenheit, or 27.8 Celcius, but there was snow on the mountain that morning. I wrote my name in it. A spruce-fir forest grows on the upper slopes, a remnant of forest that grew throughout the mountains during the last ice age. The climate at the peak of Mount LeConte is more like that of southern Canada than the warm, humid southeastern United States.

The Great Smoky Mountains National Park was established in 1934 to protect the mountains along the Tennessee/North Carolina border. No one lives in the park’s 800 square miles (2,072 square km), which receives up to 90 inches [2.29 m] of rain a year, some of it from hurricanes that sweep up from the southern Atlantic or the Gulf of Mexico. Large tracts of old-growth forest still remain in the park too.

So as you can see, the Smokies are a biodiversity hotspot. In 2018, the park announced its 1,000th species discovered that is new to science, which by July 2020 had grown to 1,025. Overall, 20,000 known species live in the park as of 2019 and scientists estimate that up to 100,000 more are yet to be discovered.

The Smokies are heavily forested, of course, but some mountain summits and crests have no trees. Instead, native grasses and shrubs grow. They’re called grassy balds and no one is sure why they exist. The prevailing theory is that Pleistocene megaherbivores opened the forests for grazing, and after their extinction, the balds remained open due to bison, elk (wapiti), and deer. When white settlers moved into the area, they used the balds to graze cattle and other livestock. Remains of mammoth and mastodon, musk ox, ground sloth, and other megaherbivores have been excavated from various balds throughout the park.

Amphibian enthusiasts call the Smokies the Salamander Capital of the World, with 30 known species. Largest of these is the hellbender, which we talked about in episode 14, a giant salamander that can grow nearly 2 ½ feet long, or 74 cm, and which lives in swift-moving mountain streams. It’s most closely related to the Chinese and Japanese giant salamanders, which can grow over twice as long as the hellbender. Twenty-seven of the salamanders found in the Smokies are lungless, in the family Plethodontidae. Instead of breathing with lungs or gills, the lungless salamanders absorb oxygen through their skin. Of these, the red-cheeked salamander is endemic to the Smokies—that is, it’s found nowhere else in the world.

The red-cheeked salamander lives in forests in high elevations. It can grow up to seven inches long, or 18 cm, and is gray or black with bright red patches on its face. It spends the day in a burrow, then comes out at night to find insects in the leaf litter. But it’s hard to tell apart from the imitator salamander, although the imitator only grows a little over four inches long, or 11 cm. The imitator has red cheeks but its body is patterned black and brown instead of solid gray or black. Sometimes its cheeks are yellow, too, while the red-cheeked salamander only ever has red cheeks.

Another animal found only in the Smoky Mountains, although it may also be present in mountains outside of the park, is a species of jeweled spider fly called Mary-Alice’s emerald (Eulonchus marialiciae). Mary-Alice’s emerald has a metallic-green body and yellow legs, and the adults eat nectar. But the larvae eat spiders. Specifically, they parasitize spiders. After hatching, the larva goes in search of a spider, especially trapdoor spiders that live in burrows. When it finds one, it works its way into the spider’s body and eats it from the inside out, eventually killing it. Then it pupates in the burrow and emerges as an adult spider fly. It prefers high elevations that are cool and moist.

A less horrific animal found in the Smokies is the Carolina northern flying squirrel. It was one of the species whose ancestors migrated south along the Appalachians during the Pleistocene. Then, after temperatures started to warm, the cold-adapted flying squirrel migrated north again. Some populations remained on mountaintops in the Smoky Mountains and have been isolated for thousands of years, evolving into a subspecies of flying squirrel found only in high elevations of the Smokies. It’s much rarer than the southern flying squirrel that lives throughout the southeastern United States, and prefers spruce forests instead of the hardwood forests that southern flying squirrels like. But the spruce forests are threatened by climate change, the introduced woolly adelgid insect that kills fir trees, and pollution in the form of acid rain and pesticides that travel to the mountains from other states and even other countries.

The Carolina northern flying squirrel has a patagium of furry skin that connects its front and back legs. When it jumps from a branch, it stretches its legs out and uses the patagia to glide to a new perch. It’s clumsy on the ground, though, and spends most of its time in trees. It mostly eats fungi, mushrooms, and lichens, but will also eat nuts, insects, bird eggs and even baby birds, and other plant material like tree sap and buds.

Bobcats still live in the Smokies, but the cougar, or mountain lion, was supposedly killed off in the area by the end of the 19th century. The U.S. Fish and Wildlife Service removed the eastern cougar subspecies from the endangered species list in 2018, since it is supposed to be extinct. The last cougar in what is now the park was supposedly killed in 1920. But sightings continue in the Smokies, close to a dozen a year, and some sightings are compelling, like the 2002 report of a cougar crossing a road in the park, spotted by a veterinarian who treated captive cougars in his practice. Considering how seldom seen the bobcat is despite it being relatively abundant, it’s possible that a small number of cougars still live in the park—either animals that have moved back into the mountains from elsewhere, or a relict population.

The red wolf is native to the eastern United States and was once common in the Smoky Mountains, but was killed off by white settlers throughout most of its range. Where it remained in the wild, it interbred with closely related coyotes, until it was declared extinct in the wild in 1980. Fortunately, by then a captive breeding program was in place. Starting in 1991, 37 red wolves were released in the Great Smoky Mountains National Park in Tennessee, following the release of 63 red wolves into the Alligator River Natural Area in North Carolina a few years earlier. But the release didn’t go well in the Smokies. Wolves are shy and need enormous territories with lots of game. Before long some wolves were leaving the park and attacking livestock. Others died of parvo virus, especially wolf pups.

Worse, this was about the same time that coyotes moved into the area from the west. The wolves started interbreeding with the coyotes, and the coyotes also competed with the wolves for food. In 1998, the Fish and Wildlife Service ended the program and recaptured all but one of the wolves originally released into the park.

The North Carolina release went better, with a population peak in 2006 estimated at nearly 130 wolves. But that program was suspended in 2015, and without management of the wild population, the number has dwindled. As of 2019, only 14 wolves remain in North Carolina—and that’s the entire population of red wolves in the wild.

But sightings of red wolves continue in the Smokies. The trouble is that the red wolf looks very similar to the coyote. It’s taller and larger, with a more pronounced reddish shade to its coat, but even experts can have trouble telling the two species apart if they can’t get a good look at the animal. Most likely people are seeing coyotes, possibly ones descended from red wolf/coyote hybrids born during the reintroduction program.

The biggest mystery in the park is the occasional sighting of a Bigfoot-type creature. Most sightings are probably bears, though. An estimated 1,500 American black bears live in the Smokies, and while some bears get used to hikers and tourists, most are shy and seldom seen. A black bear keeping an eye on hikers or cars will sometimes stand on its hind legs for a better view, and would naturally look like a hulking humanoid if glimpsed. But other sightings aren’t so easy to explain.

In February of 2009, a photographer named Deb Campbell was hiking the Middle Prong Trail in the snow. The Middle Prong Trail passes three major waterfalls and many smaller ones as it follows along a tributary of the Little River. She had the trail almost completely to herself—she says she only saw one person the whole time. Later she reported, “[A]t some point I am photographing along the stream and I start to smell a gawd awful stench. Not really like anything I had ever smelled before. I look around, see nothing, listen intently…nothing. So I finish up at that spot and go further up the trail.” The smell receded behind her but the snow increased, so finally she turned around to hike out. Around the area where she smelled the stink earlier, she started feeling watched. She stopped long enough to secure her camera gear for much faster hiking in slick conditions, when she heard a deep growl that she described as “very low, not like a cat, almost guttural.” Needless to say, she got off the mountain as quickly as possible.

The black bear doesn’t truly hibernate since its body temperature remains normal instead of dropping, but it does find a den in cold weather and will sleep for long stretches. It may emerge from its den occasionally during the winter during warm spells, but for the most part it’s asleep in its den from around November through March in the Smoky Mountains. But Campbell was hiking in February during a snowfall, with snow already on the ground. A bear would most likely not be out of its den in that weather unless it had been disturbed.

And bears don’t actually smell bad. During the winter hibernation most bears don’t defecate at all. Any feces left in a bear’s digestive tract harden to form a fecal plug. If it does feel the need to defecate near the end of the winter, it will do so just outside its den, but the fecal plug has very little odor. Even under ordinary conditions, unless a bear has been eating carrion, it will smell no worse than a dog that needs a bath.

Not only that, black bears don’t actually growl. They make grunty, huffing noises when warning people away or when males fight in the summer, and a frightened bear will moan, but they don’t growl like a dog.

It’s possible that Campbell hiked past a bear that had emerged from its den early and had found and eaten carrion, possibly roadkill, and that she was so close to the bear without seeing it that she smelled its breath. That’s almost more frightening than the thought of passing near a Bigfoot. The growl might have come from a different animal, a coyote or who knows, maybe even a red wolf. Or Campbell might have encountered a creature sometimes called a skunk ape due to its foul odor.

The skunk ape is most commonly reported in Florida swamps, but sightings—or smellings—have come from many other states. The smell is sometimes described as that of rotting food and roadkill on a hot day. A bear or other animal that has been rooting around in garbage bins can pick up this odor, especially in hot weather, but it’s hard to believe that a bear would be actively foraging so much in winter that it would smell like trash. January and February are the depths of winter in East Tennessee. The bears are hibernating, not foraging.

Thanks for your support, and thanks for listening! This is what a couple of fighting bears sound like:

[bear sounds]

Episode 475 Superweb

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This week let’s look at the work of a really astonishing number of spiders!

Further reading:

Megaweb!

Some of the webs:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Baltimore, Maryland is a city in the northeastern United States, in North America, with a population of 2.8 million people. In 1993 a new wastewater treatment plant was built called the Back River Wastewater Treatment Plant, which filters water through big sand beds to trap any particles remaining in it after it’s been filtered and treated in other facilities. The plant consists of 48 big sand beds with a corridor down the middle, and in order to keep the sand beds as clean as possible, the whole area has a big metal roof over it held up with steel columns. It doesn’t have walls, though, just a roof. The whole thing covers four acres, or 1.6 hectares, which I think is a metric term. It’s just over 16,000 square meters. It’s big, in other words, and the roof is pretty tall, up to 24 feet high over the walkway, or 7.5 meters.

Obviously, I’m telling you about this place in detail because of an animal that got into the water treatment plant and caused a lot of alarm. It wasn’t a big animal like a bear, though. It wasn’t even a dangerous animal. It was, in fact, a really small animal that’s mostly harmless to humans, various species of orbweaver spider. The problem wasn’t the spider itself but just how many spiders were in the water treatment plant.

The plant had always had problems with lots of orbweavers, but in 2009 there were so many spiders that the workers were worried for their safety. In late October 2009, the managers called for help about “an extreme spider situation.” The problem was way beyond anything that an ordinary pest control business could deal with, so the city put together a team of arachnologists, entomologists, and experts in urban pest control to figure out the best course of action.

The team didn’t just charge in, say, “Wow, that’s a lot of spiders, let’s hose the whole place down.” They were scientists and studied the situation methodically. They consulted the architectural plans of the plant to determine just how much volume was available under the roof, they took samples of the webs and stored them for study, they took over 300 photos, and basically they got as much data as they could.

There were so many spiders that their webs blended together into thick mats that filled almost every space the spiders could reach. These cobweb mats were attached to the rafters, the walkways, everywhere, with the older mats starting to detach and fray. Light fixtures hung down from the tallest point of the roof that were 8 feet long, or 2.44 meters, and there were so many webs attached to them that they were pulled out of alignment. And all the webs were filled with spiders.

The spiders in the web samples were removed and preserved, then examined to see what species they belonged to. The team identified specimens from nine genera in six families, but most of the spiders caught were the species Tetragnatha guatemalensis. This is a type of long-jawed orbweaver native to North and Central America. Females are much larger than males, with a legspan up to 2 inches across, or about 5 cm. Long-jawed orbweavers have long, thin bodies, and one of the ways it hides is by stretching out on a blade of grass or a twig with its legs out straight. It especially likes marshy areas, such as in the rafters above 48 giant sand beds full of water.

A conservative estimate of the number of spiders in the Back River Wastewater Treatment Plant in the first week of November, 2009 was 107 million. 107 million spiders! Since a big percentage of the spiders were newly hatched, there were probably a lot more in the facility than the scientists estimated from the samples they took, so there might easily have been several hundred million spiders total. The sheets of webbing in the ceiling covered an estimated 2 acres total, or about 8,000 square meters, while the cloud-like masses of webbing in other areas was about half that size and would have filled 23 railroad boxcars.

The really interesting thing is that orbweaver spiders are usually solitary. Spiders may build webs near each other, but not usually like this. But these orbweavers lived in a place protected from wind and weather, and close to water, which attracted lots of midges and other small insects, and the presence of humans probably kept a lot of potential spider predators away, like birds. Life was good for these spiders and the scientists observed that they weren’t acting aggressively to each other, even when they were of different species.

After studying the water treatment plant and its spiders, the team came to several conclusions. Since the spiders are harmless to humans, and are doing a really good job controlling the midge population, the scientists decided that pest control was not necessary and would even be a bad idea since the pesticides would inevitably get into the water. Instead, they recommended that web removal be implemented as a normal course of action when the webs started building up too much. They even suggested that the workers should be proud of their record-breaking webs, and that the plant was an ideal site for scientists to study the spiders in detail.

Thanks for your support, and thanks for listening!

Episode 473: Blue Frogs

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This week let’s learn about some blue frogs!

Further reading:

Scientists make chance discovery of rare blue skin mutation in Kimberley magnificent tree frog

White’s True-Blue Green Tree Frog

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

When most of us draw a frog, we reach for the green markers, because most frogs are green. That’s true of the magnificent tree frog, also called the splendid tree frog, which is fairly common in the Kimberley region of western Australia. It grows just over 4 inches long, snout to vent, or about 10 and a half cm, and lives in rocky areas. It spends the day hiding in rock crevices, holes in trees, or sometimes in people’s houses, and it comes out at night to hunt for insects and other small invertebrates.

From the name, you might imagine that this is an especially pretty frog, and it is. It’s mostly bright green on top and yellow to white underneath, and it has tiny yellow spots on its head and back. It looks like it has an olive green cap on its head, but that’s actually a large parotoid gland, a skin gland common in frogs and toads that secretes neurotoxins. Most frogs don’t have a parotoid gland at all, and in ones that do you typically will barely notice it, but the magnificent tree frog’s covers the entire top of its head almost to its nostrils and down onto its back.

The skin color of a frog depends on its chemical makeup. Melanophores make black and brown colors, xanthophores make yellow. Blue is different, since it’s not a color that’s actually found in skin pigments. Instead, a green frog’s skin contains iridophores that reflect blue light waves, the same way a bird’s feathers show blue. The combination of yellow and blue makes green, and the addition of melanophore pigments determine how dark or bright the green is.

In July of 2024, two land managers were working in the Charnley River-Artesian Range Wildlife Sanctuary. They were in a workshop when one of them noticed a magnificent tree frog sitting on a bench, not that unusual of an occurrence–except that this frog wasn’t green. It was blue!

The condition is called axanthism, where the yellow pigments in the frog’s skin don’t show up the way they should. Most of them time axanthism in frogs means the animal has little patches of blue or bluish coloration, but this specific frog was blue just about everywhere it should have been green. Its parotoid gland was still olive green and it had yellow on its feet, but mainly it was a very attractive dark blue.

The land managers were stunned. They took photos and sent them to pretty much everyone, and frog experts and ecologists hurried to examine the blue frog. But they decided not to keep the frog in captivity. It was released back into the wild to live out its blue froggy life normally.

Some frogs are naturally blue, like some poison dart frogs of South America. The blue poison dart frog’s legs are dark blue and its body a lighter blue with black spots. It grows less than two inches long, or about 4.5 cm. Poison dart frogs collect toxins in their bodies from some of the toxic insects they eat, and the bright coloration signals to predators that this frog will make you really sick if you eat it.

Axanthism is rare but not all that uncommon in frogs. About the same time that the blue magnificent tree frog was hopping into the workshop in Australia, two little girls playing around a pond in Nova Scotia, Canada found a teal-blue frog. Ironically, the frog is actually called the green frog and it’s ordinarily a dark olive-green all over. The girls named the frog Bluey and released it back into the pond. Another blue green frog was found in New Hampshire, in the United States, also in July 2024. In June 2024 a forest ranger spotted a northern leopard frog in Washington state that had splotches of light blue on its head and back. In May of 2024 a light blue Japanese tree frog was found by a couple on a walk.

The Australian green tree frog is closely related to the magnificent tree frog, although it doesn’t have a parotoid gland hat. It’s mostly green with a white or pale gray belly. It’s sometimes called the dumpy tree frog because it’s a little chonk. Actually, for a frog it’s a pretty big chonk, up to 4 and a half inches long, or over 11 cm. It’s also sometimes called White’s tree frog after John White, who described it in 1790. It was the first Australian frog that was ever scientifically described. But that leads us to a little mystery.

John White named the frog Rana caerulea. Its current scientific name is Ranoidea caerulea. But “caerulea” refers to the color blue, not green, as in cerulean blue.

John White collected the frog in 1788, preserved it in alcohol, and finally described it two years later. He refers to it in his writing as a blue frog and the illustration accompanying it shows frogs that are actually blue. But this frog is supposed to be green!

The main suggestion for why a famously green frog was initially described as blue is that the alcohol that White used to preserve the frog’s body actually destroyed the yellow pigment in its skin. This is something that does sometimes happen with frog specimens in museums. But it’s also possible that White ended up with a blue specimen, much like the blue magnificent tree frog we talked about earlier. He wouldn’t have known that the blue frog had a rare color mutation. That would explain why he referred to the frog as blue and gave it a name that means blue.

That might also explain why White described the Australian green tree frog first. Maybe he just thought it was pretty. Everyone likes the color blue.

Thanks for your support, and thanks for listening! I’m at Dragon Con this weekend, where who knows, I might actually see a blue frog. Anything is possible at Dragon Con.

Episode 471: Mystery Larvae

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Further reading:

I Can Has Mutant Larvae?

200-Year-Old ‘Monster Larva’ Mystery Solved

‘Snakeworm’ mystery yields species new to science

Hearkening back to the hazelworm

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

A few weeks ago when I was researching big eels, I remembered the mystery eel larva we talked about back in episode 49, and that led me down a fun rabbit hole about other mystery larvae.

Let’s start with that eel larva. Eel larvae can be extremely hard to tell apart, so as a catchall term every eel larva is called a leptocephalus. They’re flattened side to side, which is properly referred to as laterally compressed, and transparent, shaped roughly like a slender leaf, with a tiny head at the front. Depending on the species, an eel may remain in its larval form for more than a year, much longer than most other fish, and when it does metamorphose into its next life stage, it usually grows much longer than its larval form. For instance, the larvae of conger eels are only about 4 inches long, or 10 cm, while an adult conger can grow up to 10 feet long, or 3 meters.

On January 31, 1930, a Danish research ship caught an eel larva 900 feet deep, or about 275 meters, off the coast of South Africa. But the larva was over 6 feet long, or 1.85 meters!

Scientists boggled at the thought that this larva might grow into an eel more than 50 feet long, or 15 meters, raising the possibility that this unknown eel might be the basis of many sea serpent sightings.

The larva was preserved and has been studied extensively. In 1958, a similar eel larva was caught off of New Zealand. It and the 1930 specimen were determined to belong to the same species, which was named Leptocephalus giganteus.

In 1966, two more of the larvae were discovered in the stomach of a western Atlantic lancet fish. They were much smaller than the others, though—only four inches and eleven inches long, or 10 cm and 28 cm respectively. Other than size, they were pretty much identical to Leptocephalus giganteus.

The ichthyologist who examined them determined that the larvae were probably not true eels at all, but larvae of a fish called the spiny eel. Deep-sea spiny eels look superficially like eels but aren’t closely related, and while they do have a larval form that resembles that of a true eel, they’re much different in one important way. Spiny eel larvae grow larger than the adults, then shrink a little when they develop into their mature form. The six-foot eel larva was actually a spiny eel larva that was close to metamorphosing into its adult form.

Not everyone agrees that Leptocephalus giganteus is a spiny eel. Some think it belongs to the genus Coloconger, also called worm eels, which are true eels but which have large larvae that only grow to the same size as adults. But worm eels don’t grow much bigger than about two feet long, or 61 cm. If the mystery larvae does belong to the genus Coloconger, it’s probably a new species. Until scientists identify an adult Leptocephalus giganteus, we can’t know for sure.

Another mystery larva is Planctosphaera pelagica, which sits all alone in its own class because the only thing it resembles are acorn worms, but scientists are pretty sure it isn’t the larva of an acorn worm. It’s not much to look at, since the larva is just a little barrel-shaped blob that grows about 25 mm across. This sounds small compared to the eel larva we just discussed, but it’s actually quite large compared to similar larvae. Acorn worm larvae are usually only about a millimeter long.

Planctosphaera has been classified as a hemichordate, which are related to echinoderms but which show bilateral symmetry instead of radial symmetry. Hemichordates are also closely related to chordates, which include all vertebrates. They’re marine animals that resemble worms but aren’t worms, so it’s likely that Planctosphaera is also wormlike as an adult.

Planctosphaera isn’t encountered very often by scientists. It has limited swimming abilities and mostly floats around near the surface of the open ocean, eating tiny food particles. One suggestion is that it might actually be the larva of a known species, but one where an occasional larva just never metamorphoses into an adult. It just grows and grows until something eats it. So far, attempts to sequence DNA from a Planctosphaera hasn’t succeeded and attempts to raise one to maturity in captivity hasn’t worked either.

Some people have estimated that an adult Planctosphaera might be a type of acorn worm that can grow nine feet long, or 2.75 meters, which isn’t out of the realm of possibility. The largest species of acorn worm known is Balanoglossus gigas, which can grow almost six feet long, or 1.8 meters, and not only is it bioluminescent, its body contains a lot of iodine, so it smells like medicine. It lives in mucus-lined burrows on the sea floor.

Another mystery larva is Facetotecta, which have been found in shallow areas in many oceans around the world. Unlike the other larvae we’ve talked about, they’re genuinely tiny, measured in micrometers, and eleven species have been described. They all have a cephalic shield, meaning a little dome over the head, and scientists have been able to observe several phases of their development but not the adult form. The juvenile form was observed and it looked kind of like a tiny slug with nonfunctioning eyes and weak muscles.

Scientists speculate that facetotecta may actually be the larva of an endoparasite that infests some marine animals. That would explain why no adult form has been identified. Genetic testing has confirmed that Facetotecta is related to a group of parasitic crustaceans.

DNA has solved some mysteries of what larvae belong to which adults. For instance, Cerataspis monstrosa, a larval crustacean that was first described in 1828. It’s over a cm long, pinkish-purple in color with stalked eyes, little swimming leg-like appendages, and neon blue horn-like structures on its head and back which act as armor. The armor doesn’t help too much against big animals like dolphins and tuna, which love to eat it, and in fact that’s where it was initially discovered, in the digestive tract of a dolphin. But scientists had no idea what the monstrous larva eventually grew up to be.

In 2012 the mystery was solved when a team of scientists compared the monster larva’s DNA to that of lots of various types of shrimp, since the larva had long been suspected to be a type of shrimp. It turns out that it’s the larval form of a rare deep-sea aristeid shrimp that can grow up to 9 inches long, or 23 cm.

Let’s finish with another solved mystery, this one from larvae found on land. In 2007, someone sent photos and a bag of little dead worms to Derek Sikes at the University of Alaska Museum. Usually when someone sends you a bag of dead worms, they’re giving you an obscure but distressing message, but Sikes was curator of the insect collection and he was happy to get a bag of mystery worms.

The worms had been collected from an entire column of the creatures that had been crawling over each other so that the group looked like a garden hose on the ground. Sikes thought they were probably fly larvae but he had never heard of larvae traveling in a column. If you’ve listened to the hazelworm episode from August 2018, you might have an idea. The hazelworm was supposed to be a snake or even a dragon that was only seen in times of unrest. It turns out that it the larvae of some species of fungus gnat travel together in long, narrow columns that really do look like a moving snake. But that’s in Europe, not Alaska.

Sikes examined the larvae, but since they were dead he couldn’t guess what type of insect they would grow up to be. Luckily, a few months later he got a call from a forester who had spotted a column of the same worms crossing a road. Sikes got there in time to witness the phenomenon himself.

The larvae were only a few millimeters long each, but there were so many of them that the column stretched right across the road into the forest. He collected some of them carefully and took them back to the museum, where he tended them in hopes that they would pupate successfully.

This they did, and the insects that emerged were a little larger than fruit flies and were black in color. Sikes identified them as fungus gnats, but when he consulted fungus gnat experts in Germany and Japan, they were excited to report that they didn’t recognize the Alaskan gnats. It was a new species, which Sikes described in late 2023. His summer students helped name the species, Sciara serpens, which are better known now as snakeworm gnats. He and his co-authors think the larvae form columns when they cross surfaces like roads and rocks, to help minimize contacting the dry ground. Fungus gnats live in moist areas with lots of organic matter, like forest leaf litter and the edges of ponds.

So the next time you see a huge long snake crossing the road, don’t panic. It might just be a whole lot of tiny, tiny larvae looking for a new home.

Thanks for your support, and thanks for listening!

BONUS: here’s the Hazelworm episode too!

The hazelworm today is a type of reptile, although called the slow worm, blind worm, or deaf adder. It lives in Eurasia, and while it looks like a snake, it’s actually a legless lizard. It can even drop and regrow its tail like a lizard if threatened. It spends most of its time underground in burrows or underneath leaf litter or under logs. It grows almost 2 feet long, or 50 cm, and is brown. Females sometimes have blue racing stripes while males may have blue spots. It eats slugs, worms, and other small animals, so is good for the garden.

But that kind of hazelworm isn’t what we’re talking about here. Back in the middle ages in central Europe, especially in parts of the Alps, there were stories of a big dragonlike serpent that lived in areas where hazel bushes were common. Like its slow-worm namesake, it lived most of its life underground, especially twined around the roots of the hazel. Instead of scales, it had a hairy skin and was frequently white in color. It was supposed to be the same type of snake that had tempted Adam and Eve in the Garden of Eden.

It had a lot of names besides hazelworm, including white worm for its color, paradise worm for its supposed history in the Garden of Eden, and even war worm. That one was because it was only supposed to show itself just before a war broke out.

People really believed it existed, although stories about it sound more like folklore. For instance, anyone who ate hazelworm flesh was supposed to become immortal. It was also supposed to suck milk from dairy cows and spread poison.

Some accounts said it was enormous, as big around as a man’s thigh and some 18 feet long, or 5.5 meters. Sometimes it was even supposed to have feet, or have various bright colors. Sometimes drawings showed wings.

There does seem to be some confusion about stories of the hazelworm and of the tatzelwurm, especially in older accounts. But unlike the tatzelwurm, the mystery of the hazelworm has been solved for a long time—long enough that knowledge of the animal has dropped out of folklore.

Back in the 1770s, a physician named August C. Kuehn pointed out that hazelworm sightings matched up with a real animal…but not a snake. Not even any kind of reptile. Not a fish or a bird or a mammal. Nope, he pointed at the fungus gnat.

The fungus gnat is about 8 mm long and eats decaying plant matter and fungus. You know, sort of exactly not like an 18-foot hairy white snake.

But the larvae of some species of fungus gnat are called army worms. The larvae have white, gray, or brown bodies and black heads, and travel in long, wide columns that do look like a moving snake, especially if seen in poor light or in the distance. I’ve watched videos online of these processions and they are horrifying! They’re also rare, so it’s certainly possible that even people who have lived in one rural area their whole life had never seen an armyworm procession. Naturally, they’d assume they were seeing a monstrous hairy snake of some kind, because that’s what it looks like.

Sightings of smaller hazelworms may be due to the caterpillar of the pine processionary moth, which also travels in a line nose to tail, which looks remarkably like a long, thin, hairy snake. Don’t touch those caterpillars, by the way. They look fuzzy and cute but their hairs can cause painful reactions when touched.

The adult moths lay their eggs in pine trees and when the eggs hatch the larvae eat pine needles and can cause considerable damage to the trees. They overwinter in silk tents, then leave the trees in spring and travel in a snaky conga line to eat pine needles. Eventually they burrow underground to pupate. They emerge from their cocoons as adult moths, mate, lay eggs, and die, all within one day.

Episode 469: Axolotl and Friends

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Thanks to Aila, Stella, George, Richard from NC, Emilia, Emerson, and Audie for their suggestions this week!

Further reading:

Creature Feature: Snipe Eel

How removing a dam could save North Carolina’s ‘lasagna lizard’

Why Has This North Carolina Town Embraced a Strange Salamander?

Scentists search for DNA of an endangered salamander in Mexico City’s canals

An X-ray of the slender snipe eel:

The head and body of a slender snipe eel. The rest is tail [picture by opencage さん http://ww.opencage.info/pics/ – http://ww.opencage.info/pics/large_17632.asp, CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=26595467]:

The hellbender:

A wild axolotl with its natural coloration:

A captive bred axolotl exhibiting leucism:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to talk about some amphibians and fish. Thanks to Aila, Stella, George, Richard from NC, Emilia, Emerson, and Audie for their suggestions!

We’ll start with Audie’s suggestion, the sandbar shark. It’s an endangered shark that lives in shallow coastal water in the Atlantic and Indo-Pacific Oceans. A big female can grow over 8 feet long, or 2.5 meters, while males are smaller on average. It can be brown or gray in color, and its dorsal fin is especially big for a shark its size.

The sandbar shark eats fish, crustaceans like crabs, cephalopods like octopuses, and other small animals. It spends a lot of time near the bottom of the seabed, looking for food, and it will also swim into the mouths of rivers. Since it resembles a bull shark, which can live just fine in rivers for quite a while and which can be dangerous to swimmers, people are sometimes afraid of the sandbar shark, but it hardly ever bites people. It just wants to be left alone to find little fish to eat.

Emilia and Emerson both asked to learn more about eels. Eels are fish, but not every animal that’s called an eel is actually an eel. Some are just eel-shaped, meaning they’re long and slender. Electric eels aren’t actually eels, for instance, but are more closely related to catfish.

The longest eel ever reliably measured was a slender giant moray. That was in 1927 in Queensland, Australia. The eel measured just shy of 13 feet long, or 3.94 meters. We talked about some giant eels in episode 401, but this week let’s talk about a much smaller eel, one that Emerson suggested.

That’s the snipe eel, the name for a family of eels consisting of nine species known so far. They live in every ocean in the world, and some species are deep-sea animals but most live a little nearer the surface. The largest species can grow an estimated 5 feet long, or 1.5 meters, but because all species of snipe eel are so incredibly thin, even the longest individual weighs less than a football, either American or regular, take your pick.

The snipe eel gets its name from its mouth, which is long and slightly resembles the beak of a bird called the snipe. The snipe is a wading bird that pokes its long, flexible bill into mud to find small animals like insect larvae, worms, and snails. But unlike the bird’s bill, the snipe eel’s jaws have a bend at the tip. The upper jaw bends upward, the lower jaw bends downward so that the tip of the jaws are separated. It doesn’t look like that would be very helpful for catching food, but scientists think it helps because the fish’s mouth is basically always open. Since it mainly eats tiny crustaceans floating in the water, it doesn’t even need to open its mouth to catch food. It has tiny teeth along the jaws that point backwards, so when a crustacean gets caught on the teeth, it can’t escape.

The slender snipe eel is especially unusual because it can have as many as 750 vertebrae in its backbone. That’s more than any other animal known. Most of its length is basically just an incredibly long, thin tail, with its organs bunched up right behind its head. Even its anus is basically on its throat.

We don’t know a whole lot about the snipe eel, since it lives deep enough that it’s hardly ever seen by humans. Most of the specimens discovered have been found in the stomachs of larger fish.

Now, let’s leave the world of fish behind and look at some amphibians. First, George wanted to learn about the hellbender, and points out that it’s also called the snot otter or lasagna lizard. I don’t understand the lasagna part but it’s funny.

The hellbender is a giant salamander that lives in parts of the eastern United States, especially in the Appalachian Mountains and the Ozarks. It can grow nearly 30 inches long, or 74 cm, and is the fifth heaviest amphibian alive today in the whole world. It spends almost all its life in shallow, fast-moving streams hiding among rocks. As water rushes over and around rocks, it absorbs more oxygen, which is good for the hellbender because as an adult it breathes through its skin. To increase its surface area and help it absorb that much more oxygen, its skin is loose and has folds along the sides.

The hellbender is flattened in shape and is brown with black speckles on its back. It mostly eats crayfish, but it will also eat frogs and other small animals. Its skin contains light-sensitive cells, which means that it can actually sense how much light is shining on its body even if its head is hidden under a rock, so it can hide better.

Aila and Stella suggested we talk about the axolotl, and a few years ago Richard from NC sent me a lot of really good information about this friendly-looking amphibian. I’d been planning to do a deep dive about the axolotl, which we haven’t talked about since episode 275, but sometimes having a lot of information leads to overload and I never did get around to sorting through everything Richard sent me.

Richard also suggested we talk about a rare mudpuppy, so let’s learn about it before we get to the axolotl. It’s called the Neuse river waterdog, although Richard refers to it as the North Carolina axolotl because it resembles the axolotl in some ways, although the two species aren’t very closely related.

The mudpuppy, also called the waterdog, looks a lot like a juvenile hellbender but isn’t as big, with the largest measured adult growing just over 17 inches long, or almost 44 cm. It lives in lakes, ponds, and streams and retains its gills throughout its life.

The mudpuppy is gray, black, or reddish-brown. It has a lot of tiny teeth where you’d expect to find teeth, and more teeth on the roof of its mouth where you would not typically expect to find teeth. It needs all these teeth because it eats slippery food like small fish, worms, and frogs, along with insects and other small animals.

The Neuse River waterdog lives in two watersheds in North Carolina, and nowhere else in the world. It will build a little nest under a rock by using its nose like a shovel, pushing at the sand, gravel, and mud until it has a safe place to rest. If another waterdog approaches its nest, the owner will attack and bite it to drive it away.

The mudpuppy exhibits neoteny, a trait it shares with the axolotl. In most salamanders, the egg hatches into a larval salamander that lives in water, which means it has external gills so it can breathe underwater. It grows and ultimately metamorphoses into a juvenile salamander that spends most of its time on land, so it loses its external gills in the metamorphosis. Eventually it takes on its adult coloration and pattern. But neither the mudpuppy nor the axolotl metamorphose. Even when it matures, the adult still looks kind of like a big larva, complete with external gills, and it lives underwater its whole life.

The axolotl originally lived in wetlands and lakes in the Mexico Central Valley. This is where Mexico City is and it’s been a hub of civilization for thousands of years. A million people lived there in 1521 when the Spanish invaded and destroyed the Aztec Empire with introduced diseases and war. The axolotl was an important food of the Aztecs and the civilizations that preceded them, and if you’ve only ever seen pictures of axolotls you may wonder why. Salamanders are usually small, but a full-grown axolotl can grow up to 18 inches long, or 45 cm, although most are about half that length.

Most wild axolotls are brown, greenish-brown, or gray, often with lighter speckles. They can even change color somewhat to blend in with their surroundings better. Captive-bred axolotls are usually white or pink, or sometimes other colors or patterns. That’s because they’re bred for the pet trade and for medical research, because not only are they cute and relatively easy to keep in captivity, they have some amazing abilities. Their ability to regenerate lost and injured body parts is remarkable even for amphibians. Researchers study axolotls to learn more about how regeneration works, how genetics of coloration work, and much more. They’re so common in laboratory studies that you’d think there’s no way they could be endangered—but they are.

A lot of the wetlands where the axolotl used to live have been destroyed as Mexico City grows. One of the lakes where it lived has been completely filled in. Its remaining habitat is polluted and contains a lot of introduced species, like carp, that eat young axolotls as well as the same foods that axolotls eat. Conservationists have been working hard to improve the water quality in some areas by filtering out pollutants, and putting up special barriers that keep introduced fish species out.

Even if the axolotl’s habitat was pristine, though, it wouldn’t be easy to repopulate the area right away. Axolotls bred for the pet trade and research aren’t genetically suited for life in the wild anymore, since they’re all descended from a small number of individuals caught in 1864, so they’re all pretty inbred by now.

Mexican scientists and conservationists are working with universities and zoos around the world to develop a breeding program for wild-caught axolotls. So far, the offspring of wild-caught axolotls that are raised in as natural a captive environment as possible have done well when introduced into the wild. The hard part is finding wild axolotls, because they’re so rare and so hard to spot.

Scientists have started testing water for traces of axolotl DNA to help them determine if there are any to find in a particular area. If so, they send volunteers into the water with nets and a lot of patience to find them.

The axolotl reproduces quickly and does well in captivity. Hopefully its habitat can be cleaned up soon, which isn’t just good for the axolotl, it’s good for the people of Mexico City too.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, corrections, or suggestions, email us at strangeanimalspodcast@gmail.com.

Thanks for listening!

Episode 468: Tamarins and Other Mammals

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Thanks to Conner, Tim, Stella, Cillian, Eilee, PJ, and Morris for their suggestions this week!

Further reading:

Extinct Hippo-Like Creature Discovered Hidden in Museum: ‘Sheer Chance’

The golden lion tamarin has very thin fingers and sometimes it’s rude:

The golden lion tamarin also has a very long tail:

The cotton-top tamarin [picture by Chensiyuan – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=153317160]:

The pangolin is scaly:

The pangolin can also be round:

The East Siberia lemming [photo by Ansgar Walk – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=52651170]:

An early painting of a mammoth:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to look at some mammals suggested by Conner, Tim, Stella, Cillian, Eilee, PJ, and Morris. Let’s jump right in, because we have a lot of fascinating animals to learn about!

We’ll start with suggestions by Cillian and Eilee, who both suggested a monkey called the tamarin. Tamarins live in Central and South America and there are around 20 species, all of them quite small.

Cillian specifically suggested the golden lion tamarin, an endangered species that lives in a single small part of Brazil. It has beautiful golden or orange fur that’s longer around the face, like a lion’s mane but extremely stylish. Its face is bare of fur and is gray or grayish-pink in color, with dark eyes and a serious expression like it’s not sure where it left its wallet. It grows about 10 inches long, or 26 cm, not counting its extremely long tail.

The golden lion tamarin spends most of its time in trees, where it eats fruit, flowers, and other plant material, along with eggs, tree frogs, insects, and other small animals. It has narrow hands and long fingers to help it reach into little tree hollows and crevices where insects are hiding, but if it can’t reach an insect that way, it will use a twig or other tool to help.

The golden lion tamarin lives in small family groups, usually a mated pair and their young children. A mother golden lion tamarin often has twins, sometimes triplets, and the other members of her family help take care of the babies.

Because the golden lion tamarin is endangered, mainly due to habitat loss, zoos throughout the world have helped increase the number of babies born in captivity. When it’s safe to release them into the wild, instead of only releasing the young tamarins, the entire family group is released together.

Eilee suggested the cotton-top tamarin, which lives in one small part of Colombia. It’s about the same size as the golden lion tamarin, but is more lightly built and has a somewhat shorter tail. It’s mostly various shades of brown and tan with a dark gray face, but it also has long white hair on its head. Its hair sticks up and makes it look a little bit like those pictures of Einstein, if Einstein was a tiny little monkey.

Like the golden lion tamarin, the cotton-top tamarin lives in small groups and eats both plant material and insects. It’s also critically endangered due to habitat loss, and it’s strictly protected these days.

Next, both Tim and Stella suggested we learn about the pangolin. There are eight species known, which live in parts of Africa and Asia.

The pangolin is a mammal, but it’s covered in scales except for its belly and face. The scales are made of keratin, the same protein that makes up fingernails, hair, hooves, and other hard parts in mammals. When it’s threatened, it rolls up into a ball with its tail over its face, and the sharp-edged, overlapping scales protect it from being bitten or clawed. It has a long, thick tail, short, strong legs with claws, a small head, and very small ears. Its muzzle is long with a nose pad at the end, it has a long sticky tongue, and it has no teeth. It’s nocturnal and uses its big front claws to dig into termite mounds and ant colonies. It has poor vision but a good sense of smell.

Some species of pangolin live in trees and spend the daytime sleeping in a hollow tree. Other species live on the ground and dig deep burrows to sleep in during the day. It’s a solitary animal and just about the only time adult pangolins spend time together is when a pair comes together to mate. Sometimes two males fight over a female, and they do so by slapping each other with their big tails.

Unfortunately for the pangolin, its scales make it sought after by humans for decoration. People also eat pangolins. Habitat loss is also making it tough for the pangolin. All species of pangolin in Asia are endangered or critically endangered, while all species of pangolins in Africa are vulnerable. Pangolins also don’t do well in captivity so it’s hard for zoos to help them.

Next, Conner wants to learn about the lemming, a rodent that’s related to muskrats and voles. Lots of people think they know one thing about the lemming, but that thing isn’t true. We’ll talk about it in a minute.

The lemming grows up to 7 inches long, or 18 cm, and is a little round rodent with small ears, a short tail, short legs, and long fur that’s brown and black in color. It eats plant material, and while it lives in really cold parts of the northern hemisphere, including Siberia, Alaska, northern Canada, and Greenland, it doesn’t hibernate. It just digs tunnels with cozy nesting burrows to warm up in, and finds food by digging tunnels in the snow.

Lemmings reproduce quickly, which is a trait common among rodents, and if the population of lemmings gets too large in one area, some of the lemmings may migrate to find a new place to live. In the olden days people didn’t understand lemming migration. Some people believed that lemmings traveled through the air in stormy weather and that’s why a bunch of lemmings would suddenly appear out of nowhere sometimes. They’d just drop out of the sky. Other people were convinced that if there were too many lemmings, they’d all jump off a cliff and die on purpose, and that’s why sometimes there’d be a lot of lemmings, and then suddenly one day not nearly as many lemmings.

Many people still think that lemmings jump off cliffs, but this isn’t actually true. They’re cute little animals, but they’re not dumb.

Next, let’s learn about two extinct animals, starting with PJ’s suggestion, the woolly mammoth. We actually know a lot about the various species of mammoth because we have so many remains. Our own distant ancestors left cave paintings and carvings of mammoths, we have lots of fossilized remains, and we have lots of subfossil remains too. Because the mammoth lived so recently and sometimes in places where the climate hasn’t changed all that much in the last 10,000 years, namely very cold parts of the world with deep layers of permafrost beneath the surface, sometimes mammoth remains are found that look extremely fresh.

The woolly mammoth was closely related to the modern Asian elephant, but it was much bigger and covered with long fur. A big male woolly mammoth could stand well over 11 feet tall at the shoulder, or 3.5 meters, while females were a little smaller on average. It was well adapted to cold weather and had small ears, a short tail, a thick layer of fat under the skin, and an undercoat of soft, warm hair that was protected by longer guard hairs. It lived in the steppes of northern Europe, Asia, and North America, and like modern elephants it ate plants. It had long, curved tusks that could be over 13 feet long, or 4 meters, in a big male, and one of the things it used it tusks for was to sweep snow away from plants.

The woolly mammoth went extinct at the end of the last ice age, around 11,000 years ago, although a small population remained on a remote island until only 4,000 years ago.

Our last animal this week is Morris’s suggestion, and it’s actually not a single type of animal but a whole order. Desmostylians were big aquatic mammals, and the only known order of aquatic mammals that are completely extinct.

When you think of aquatic mammals, you might think of whales, seals, and sea cows, or even hippos. Desmostylians didn’t look like any of those animals, and they had features not found in any other animal.

Desmostylians lived in shallow water off the Pacific coast, and fossils have been found in North America, southern Japan, parts of Russia, and other places. They first appear in the fossil record around 30 million years ago and disappear from the fossil record about 7 million years ago. They were fully aquatic animals that probably mostly ate kelp or sea grass, similar to modern sirenians, which include dugongs and manatees.

Let’s talk about Paleoparadoxia to find out roughly what Desmostylians looked and acted like. Paleoparadoxia grew about 7 feet long, or 2.15 meters, and had a robust skeleton. It had short legs, although the front legs were longer and its four toes were probably webbed to help it swim. It probably acted a lot like a sirenian, walking along the sea floor to find plants to eat. Its nostrils were on the top of its nose so it could take breaths at the surface more easily, and it had short tusks in its mouth, something like modern hippos. It may have looked a little like a hippo, but also a little like a dugong, and possibly a little like a walrus.

One really strange thing about Desmostylians in general are their teeth. No other animals known have teeth like theirs. Their molars and premolars are incredibly tough and are made up of little enamel cylinders. The order’s name actually means “bundle of columns,” referring to the teeth, and the bundles point upward so that the tops of the columns make up the tooth’s chewing surface. Actually, chewing surface isn’t the right term because Desmostylians probably didn’t chew their food. Scientists think they pulled plants up by the roots using their teeth and tusks, then used suction to slurp up the plants and swallow them whole.

We still don’t know very much about Desmostylians. Scientists think they were outcompeted by sirenians, but we don’t really know why they went extinct. We don’t even know what they were most closely related to. They share some similarities with manatees and elephants, but those similarities may be due to convergent evolution. Then again, they might be related. Until we find more fossils, the mysteries will remain.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, corrections, or suggestions, email us at strangeanimalspodcast@gmail.com.

Thanks for listening!

Episode 467: The Dragon Bird and Friends

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Thanks to Audie, Katie, Eilee, Emily, Maryjane, and Dylan for their suggestions this week! Sorry this episode is late–the site was down. 🙁

Further reading:

Bobolinks

A frill-neck lizard showing off:

A bobolink:

The great-eared nightjar [picture by Venkata Shreeram Mallimadugula, taken from this site]:

Another great-eared nightjar [Picture by Nigel Voaden from UK – Great Eared-Nightjar, Tangkoko, Sulawesi, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=39857392]:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we have an episode about some birds and reptiles. Thanks to Audie, Katie, Eilee, Emily, Maryjane, and Dylan for their suggestions! If this episode showed up later than usual in the podcast feed, it’s because I’ve been having trouble with the website and couldn’t get it uploaded until it was fixed.

We’ll kick off the episode with an animal that can’t kick, because snakes don’t have any legs. Audie suggested we learn about the scaleless rat snake, which means that first we have to learn about the rat snake, the ordinary one with scales.

Rat snakes are constrictors and are common throughout many parts of Asia, Europe, North America, and the Middle East, and they’re called rat snakes because they eat rats and other small animals like lizards, frogs, and baby birds.

Rat snakes are popular pets because they’re so pretty and they aren’t dangerous to humans. Different species are different colors and patterns, and the rhinoceros rat snake, also called the Vietnamese longnose snake, even has a little hornlike projection on the tip of its nose that points forward. I’m pretty sure we’ve talked about that particular rat snake before on the podcast, but I can’t look up which episode because the website is down.

Most rat snakes don’t grow much bigger than 5 feet long, or 1.5 meters, but a few species can get longer than that. The black rat snake, which lives in North America, can grow over 8 feet long, or more than 2.5 meters. It’s black with small white markings on the head, but snakes bred for sale as pets are sometimes white all over or partially white, or even albino, meaning an individual has a mutation where its body doesn’t produce pigment. Pet black rat snakes are also bred that don’t have scales.

That brings us to the scaleless rat snake. It’s an ordinary rat snake but it has a mutation that causes it to have very few scales. This is a mutation that happens occasionally in the wild since it’s a recessive trait, and while it can make the snake a little more vulnerable to injury, scaleless snakes can survive just fine in the wild. They do have belly scales like a normal snake, which are the ones that allow them to move around, and they may have a scattering of scales on other parts of the body too. A scaleless snake still sheds its skin once a year like an ordinary snake, since it’s actually the outer layer of skin that sheds along with the scales.

Scaleless rat snakes are popular as pets because they’re so soft and because their coloration is usually very bright. A snake’s coloration comes from pigments in its skin. A snake’s scales are actually transparent, so without a layer of scales, a scaleless snake looks even more colorful than a regular snake. Many species of snake have been found in the wild that are scaleless, but it seems to be a little more common in rat snakes.

Next, Dylan and Emily wanted to learn about the frill-neck lizard, which is found in northern Australia and the very southern part of New Guinea. It’s a big lizard that can grow almost three feet long, or 90 cm, including its incredibly long tail. Males are larger than females on average, with a bigger frill.

The frill is a flap of skin around the head and neck, and most of the time it’s folded back over the neck and shoulders so it’s not that noticeable. The lizard is pretty ordinary-looking that way, just a big gray or brown animal with a big head. But when the lizard feels threatened, or if it comes across another frill-neck lizard, it can extend the frill by moving the small bones and cartilage that act as struts, which also requires the lizard to open its mouth.

When extended, the frill is as much as a foot across, or 30 cm, and it’s marked with bright colors. Different individuals have different colored frills, red, orange, yellow, or white, or a mixture of colors and patterns. The size and color of the frill opening up so quickly will often startle a potential predator, allowing the lizard to escape. The frill-neck lizard can even run on two legs if it needs to, although it has to run with its head pointing straight up in the air.

The frill-neck lizard mostly eats insects, especially termites. It spends most of its time in trees and some people believe it can use its frill as a parachute, but that doesn’t actually seem to be the case.

Let’s move on to a few birds next. Maryjane suggested we learn about the bobolink, a type of blackbird native to the Americas. In summer the male bobolink is black with a pale yellow nape and white markings, and in winter he molts into a drab outfit of brown to help him hide. The female is brown with black streaks and stripes.

In the summer the bobolink flies to the northern United States and Canada to nest and raise babies, and it migrates to southern South America in winter. This is a huge distance for such a little songbird to travel, but it’s a strong flyer and can travel over a thousand miles, or 1,800 km, in a single day. It navigates using the stars at night and can sense the earth’s magnetic field too, which helps it find its way.

The bobolink prefers prairies and grassy areas. It eats seeds and insects, and especially likes rice and a type of caterpillar called the armyworm. It’s sometimes considered a pest because it eats so much rice, but then again armyworms are also considered pests and the bobolink eats so many of them that it has probably saved a lot of crops that way. While the bobolink is still numerous, its numbers have been in decline for years due to habitat loss.

The bobolink is most famous for its song. Both males and females sing, and males not only sing while perched, they sing while flying. The bobolink’s songs are varied and lovely. This is what the bobolink sounds like, first a song recorded while the bird was flying:

[bobolink song]

And here’s another song recorded while a different bird in a different place was perched and singing:

[bobolink song]

Finally, both Katie and Eilee wanted to learn about the great-eared nightjar, also called the dragon bird or the baby dragon.

Nightjars are nocturnal birds, and the great-eared nightjar is found in parts of southern and Southeast Asia. It can grow up to 16 inches long, or 41 cm, and is a chonky bird with big dark eyes and a broad bill that can open very wide. The “ears” in its name are tufts of feathers on the top of its head that look like ears or little horns. It can raise the ears if it wants to, but most of the time they just stick out backwards. Like other nightjars, the great-eared nightjar’s head looks flattened most of the time, and the bird itself spends a lot of time crouched down looking like a very flat bird, but then it sits up and pricks up its ear tufts, and it looks more like a thin owl with a long tail. The bird is brown with black markings, which makes it almost invisible at night.

During the day, the great-eared nightjar sits in a tree or just on the forest floor, so well camouflaged by its feathers that it blends in with the leaf litter or kind of looks like a piece of stump or broken-off branch. At night it flies around catching insects on the wing like a bat.

Instead of building a nest and laying eggs in it like other birds, the great-eared nightjar just lays a single egg among dead leaves on the ground. The egg, and the baby when it hatches, are so well camouflaged that it’s as safe on the ground as it would be in a nest way up in a tree.

The great-eared nightjar has an eerie call. This is what it sounds like:

[great-eared nightjar call]

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, corrections, or suggestions, email us at strangeanimalspodcast@gmail.com.

Thanks for listening!

Episode 465: The Mermaid

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Thanks to Holly for suggesting this week’s topic!

Further reading:

Mermaids: Myth, Kith and Kin [this article is not for children]

Feejee Mermaid

A manatee:

A female grey seal, looking winsome:

A drawing of the “original” Fiji (or Feejee) mermaid:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Let’s close out the year 2025 with a mystery episode! Holly suggested we talk about mermaids!

Mermaids are creatures of folklore who are supposed to look like humans, but instead of legs they have fish tails. These days mermaids are usually depicted with a single tail, but it was common in older artwork for a mermaid to be shown with two tails, which replaced both legs. Not all mermaids were girls, either. Mermen were just as common.

Cultures from around the world have stories about mermaid-like individuals. Sometimes they’re gods or goddesses, like the Syrian story of a goddess so beautiful that when she transformed into a fish, only her legs changed, because her upper half was too beautiful to alter, or the Greek god Triton, who is usually depicted as a man with two fish tails for legs. Sometimes they’re monsters who cause storms, curse ships, or lure sailors to their doom. Sometimes they can transform into humans, like the story from Madagascar about a fisherman who catches a mermaid in his net. She transforms into a human woman and they get married, but when he breaks a promise to her, she turns back into a mermaid and swims away.

In 2012, a TV special aired on Animal Planet that claimed that mermaids were real, and a lot of people believed it. It imitated the kind of real documentaries that Animal Planet often ran, and the only disclaimer was in the credits. I remember how upset a lot of people were about it, especially teachers and scientists. So just to be clear, mermaids aren’t real.

Many researchers think at least some mermaid stories might be based on real animals. The explorer Christopher Columbus reported seeing three mermaids in 1493, but said they weren’t as beautiful as he’d heard. Most researchers think he actually saw manatees. A few centuries later, a mermaid was captured and killed off the coast of Brazil by European scientists, and the careful drawings we still have of the mermaid’s hand bones correspond exactly to the bones of a manatee’s flipper.

Female manatees are larger than males on average, and a really big female can grow over 15 feet long, or 4.6 meters. Most manatees are between 9 and 10 feet long, or a little less than 3 meters. Its body is elongated like a whale’s, but unlike a whale it’s slow, usually only swimming about as fast as a human can swim. Its skin is gray or brown although often it has algae growing on it that helps camouflage it. The end of the manatee’s tail looks like a rounded paddle, and it has front flippers but no rear limbs. Its face is rounded with a prehensile upper lip covered with bristly whiskers, which it uses to find and gather water plants.

The manatee doesn’t look a lot like a person, but it looks more like a person than most water animals. It has a neck and can turn its head like a person, its flippers are fairly long and resemble arms, and females have a pair of teats that are near their armpits, if a manatee had armpits, which it does not. But that’s close enough for Christopher Columbus to decide he was seeing a mermaid.

Seals may have also contributed to mermaid stories. In Scottish folklore, the selkie is a seal that can transform into human shape, usually by taking off its skin. There are lots of stories of people who steal the selkie’s skin and hide it so that the selkie will marry the person—because selkies are beautiful in their human form. Eventually the selkie finds the hidden skin and returns to the sea.

Similar seal-folk legends are found in other parts of northern Europe, including Sweden, Iceland, Norway, and Ireland. Many of the stories overlap with mermaid stories. Seals do have appealing human-like faces, have clawed front flippers that sort of resemble arms, and have rear flippers that are fused to act like a tail, even if it doesn’t look much like a fish tail.

The grey seal is a common animal off the coast of northern Europe, and a big male can grow almost 11 feet long, or 3.3 meters, although 9 feet is more common, or 2.7 meters. It has a large snout and no external ear flaps. Males are dark grey or brown, females are more silvery in color. It mainly eats fish, but will also eat other animals, including crustaceans, octopuses, other seals, and even porpoises.

While I don’t think it has anything to do with the mermaid or selkie legends, it is interesting to note that seals are good at imitating human voices. We learned about this in episode 225, about talking mammals. For instance, Hoover the talking seal, a harbor seal from Maine who was raised by a human after his mother died. Imagine if you were walking along the shore and a seal said this to you:

[Hoover the talking seal saying “Hey get over here!”]

Let’s finish with the Japanese legend of the ningyo and a weird taxidermy creature called the Feejee mermaid. The ningyo is a being of folklore that dates back to at least the 7th century. It was a fish with a head like a person, usually found in the ocean but sometimes in freshwater. If someone found a ningyo washed up on shore, it was supposed to be a bad omen, foretelling war and other disasters.

If you remember the big fish episode a few weeks ago, if an oarfish is found near the surface of the ocean around Japan, it’s supposed to foretell an earthquake. The oarfish has a red fin that runs from its head down its spine, like a mane or a comb, and the ningyo was also supposed to have a red comb on its head, like a rooster’s comb, or sometimes red hair. Some people think the ningyo is based on the oarfish. The oarfish is a deep-sea fish so it’s rare, usually only seen near the surface when it’s dying, and it has a flat face that looks more like a human face than most fish, if you squint and really want to believe you’re seeing a mythical creature.

These days, artwork of the ningyo usually looks a lot more like mermaids of European legend, but the earliest paintings don’t usually have arms, just a human head on a fish body. But by the late 18th century, a weird type of artwork had become popular among Japanese fishermen, a type of crude but inventive taxidermy that created what looked like small, creepy mermaids.

They looked like dried-out monkeys from the waist up, with a dried-out fish tail instead of legs. That’s because that’s exactly what they were. Japanese fishermen made these mermaids along with lots of other monsters, and sold them to travelers for high prices. The fishermen told tall tales about how they’d found the monster, killed it, and preserved it, and pretended to be reluctant to sell it, and of course that meant the traveler would offer even more money for it.

The most famous of these fake monsters was called the Fiji Mermaid, and it got famous because P.T. Barnum displayed it in his museum in 1842 and said it had been caught near the Fiji Islands, in the South Pacific. It was about three feet along, or 91 cm, and was probably made from a young monkey and a salmon.

The original Fiji mermaid was probably destroyed in a fire at some point, but it was such a popular exhibit that other wannabe showmen either bought or made replicas, some of which are still around today. People still sometimes make similar monsters, but they use craft materials instead of dead animals. They’re still creepy-looking, though, which is part of the fun.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, corrections, or suggestions, email us at strangeanimalspodcast@gmail.com.

Thanks for listening!