Episode 109: Convergent Evolution

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I mention convergent evolution occasionally, but what is it really? This week we learn about what it is and some animals that demonstrate it. Thanks to Richard E. and Llewelly for their suggestions this week! Jaguars and leopards look so similar I’m not 100% sure this picture actually shows one of each:

The adorable sucker-footed bat from Madagascar:

The equally adorable TOTALLY UNRELATED disk-winged bat from South America:

Metriorhynchus looked a lot like a whale even though it was a crocodile ancestor:

Show transcript:

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

This week we’re going to learn about some animals that represent convergent evolution. That’s a term that I mention every so often, so it’s time to really dig into it and see what it’s all about. We’ll start with animals that are fairly closely related, then work our way backwards to those that aren’t related at all.

Basically, when unrelated organisms develop similar form, structure, or functions as each other, that’s called convergent evolution. One simple example is bats and birds. They’re not related, but both can fly using forelimbs that have been modified into wings.

This topic idea was sparked by an idea from Richard E., who suggested an episode about evolution and how it doesn’t “improve” anything, just adapts. That’s an important distinction. Evolution is a reactive force, not a proactive. Sometimes we use terms like advanced to describe certain animals, and primitive to describe others with traits that haven’t changed in a long time. That implies that some animals are “better” than others, or better adapted. In actuality, one trait is not better or worse than another, as long as both traits help the animal survive and thrive. If an animal has traits that haven’t changed in millions of years but it’s still doing well, it’s as adapted as it needs to be. An animal that’s extremely specialized to an environment can sometimes be much more vulnerable to environmental change than a more generalized animal, too.

From a scientific point of view, while it may look like species become more advanced as time goes on, all it means is that a lot of animals have evolved to occupy specific ecological niches. One example Richard gives is the panda, which we talked about in episode 42 about strange bears.

The panda is an extremely specialized animal. It’s a bear that is no longer a carnivore, for one thing, and not only does it not eat meat, or hardly any meat since it will eat small animals and bird eggs when it finds them, it mostly just eats one type of plant. That plant, of course, is bamboo, which is low in nutrients. The panda has adapted in all sorts of ways to be able to digest bamboo, and one of the most obvious adaptations is what looks like a sixth toe on its forefeet. It’s not a toe but a projecting sesamoid bone that acts as a toe and helps the panda grasp bamboo.

But the panda’s sixth toe evolved because of selective pressures, because pandas born with the toe were able to eat more bamboo and were therefore healthier and more likely to have babies than pandas without the toe.

Richard also mentioned the similarities between jaguars and leopards. They are related, but not closely. The jaguar is more closely related to the leopard than to the lion, but the leopard is more closely related to the lion than to the jaguar. That’s not confusing at all. But both cats look very similar, tawny or golden in color with black spots called rosettes, and both frequently demonstrate an all-black coloring called melanism. But the jaguar lives in the Americas while the leopard lives in Asia and parts of Africa. Why do they look so similar?

In this case, a big part of the similarities between jaguars and leopards are that they share a common ancestor that lived around three and a half million years ago. The jaguar migrated from Africa into Europe and then into North America on the land bridge Beringia, while the leopard mostly stayed put but expanded its territory into Asia. New research into feline genetics suggests that the jaguar interbred with lions at some point, which gave it a heavier build and stronger jaws than the leopard.

But leopards and jaguars look very different from other big cats, and very similar to each other. This is where convergent evolution comes in. Leopards and jaguars live in similar habitats, dense forests and jungle where light is dim and filtered through leaves. A spotted animal is harder to see where there’s a lot of dappled shade, and an all-black animal is harder to see when there’s not a lot of light. Melanistic jaguars, those that are all-black, are extremely common, and melanistic leopards are more common in populations living in thicker forests than in populations that live in more open forests with more light.

Leopards and jaguars share a genus, Panthera, which means they’re pretty closely related. But Llewelly suggested we talk about sucker-footed and disk-winged bats, and while they’re both microbats, they’re much less closely related than jaguars and leopards. And they share a really weird adaptation for climbing on smooth leaves.

The sucker-footed bat lives in Madagascar, the big island off the coast of Africa that’s full of lemurs. Madagascar is also home to a tree called the traveler’s palm, although it’s not actually a palm tree. It’s an amazing tree with huge leaves that grow in a fan shape. I don’t mean the tree has a lot of leaves growing in fan shapes, I mean the main part of the tree is one giant fan of enormous leaves. The leaves can be 36 feet long, or 11 meters, and some trees can grow 100 feet high, or 30 meters. It’s supposedly called the traveler’s palm because the fan tends to grow along an east-west line so it gets the most sun, or possibly because the stems catch and hold rainwater that thirsty travelers could drink. Its white flowers are pollinated by ruffed lemurs and it has bright blue seeds. But the traveler’s palm also has extremely smooth leaves, and the sucker-footed bat roosts on the leaves. But the leaves are so slick and smooth that most insects can’t even hold on to them. How does a bat manage it?

As you may have guessed from the name, the sucker-footed bat has little cuplike pieces of skin on its thumb joint and its feet that excrete lots of sweat-like fluid. The bat presses the cups against the leaf and they act just like suction cups, although the main suction comes from wet adhesion. You know how a suction cup holds better if you lick it first? That’s pretty much how it works. Also, hey kids, don’t lick suction cups, they’re dirty. Also don’t drink rainwater out of leaves, that sounds clean but it’s full of dirt and drowned bugs.

The sucker-footed bat roosts head-up instead of hanging upside-down, only one of six species known to roost head-up. It’s about two inches long, or 5 cm, and eats insects. Because it mostly only roosts in the traveler’s palm and is mostly solitary, it doesn’t carry any parasites in its fur or on its skin. Parasites can’t walk across those slick leaves.

The disk-winged bat, meanwhile, lives in the tropical parts of Central and South America. Like the sucker-footed bat, it has cuplike discs made of skin and cartilage on its thumbs and feet that act as suction cups. It roosts head-up in smooth curled-up leaves, generally in small groups. But its suction cups are different from the sucker-footed bat’s. They actually use suction to stay in place, whereas the sucker-footed bat’s suction cups mostly just use wet adhesion from the sweat it produces, with the actual suction being weak and not really necessary.

So let’s back it up some more and look at two animals that have evolved in similar directions that aren’t related. Like crocodiles and whales, or at least a crocodile relative and modern dolphins.

Metriorhynchids [met-ree-oh-rink-id] were croc relatives that lived around 150 million years ago, about 100 million years before whales and their relatives evolved. Metriorhynchids were marine animals, and while we don’t know a whole lot about them since we don’t have very many fossils, we do know that they grew up to ten feet long, or three meters, and lived in the ocean.

Metriorhynchus ate fish, ammonites, and whatever else it could catch, and it was a fast swimmer. It was streamlined with a long snout, smooth skin instead of armored, and even had a finned tail sort of like a shark’s that probably provided its propulsion through the water. It had four long flippers to help it maneuver.

In other words, in a lot of ways it looked like a dolphin, because it was so well adapted to live in the same environment. Whales and their relations have streamlined shapes, smooth bodies to reduce drag in the water, fluked tails, and flippers. Even the shape of metriorhynchus’s snout mirrors the longer rostrums that some dolphins have evolved to help them catch prey.

Finally, let’s look at convergent evolution between two animals that look totally different, are totally unrelated, but which share one similar feature. If you guessed primates and parrots, you are correct!

Specifically, this is about how the brain manages higher-order processing. In other words, intelligence. Primates, including humans, have an enlarged section of the brain called the pontine nuclei that transfers information between the brain’s cortex and cerebellum, allowing primates to process information in a more sophisticated way than most other mammals studied. But parrots and a lot of other birds are also intelligent, and researchers have recently discovered how their brains do the same thing.

Instead of a big pontine nuclei, birds use a part of the brain called the medial spiriform nucleus that performs the same transfer of information from the cortex and the cerebellum. In intelligent birds like parrots, that part of the brain is very large, five times larger than it is in chickens. I’m sorry, chickens, you’re very pretty birds and taste delicious, but you’re not known for your high-level reasoning abilities.

So convergent evolution is more than just two animals that evolve to look or act similar because they live in the same environment. In fact, there’s so much to convergent evolution that there’s no way I can do more than brush along the surface of the topic in a single episode. It might be a fun topic to revisit now and then.

In the meantime, now you know a little bit about what convergent evolution is. Just remember that if you explain it to a parrot, it’s processing your information with a totally different part of its brain than you are. That’s pretty awesome.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

 

Episode 108: Strange Things Found in Amber

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Thanks to Nicholas for suggesting this week’s episode topic! Lots of strange and fascinating insects and other animals are found trapped in amber. So what is amber, how does it preserve animal parts, and most importantly, what have scientists found in amber?

A millipede preserved in amber, one of 450 millipedes discovered in Myanmar amber. Somebody had to count them:

A newly described insect that got its own order because it’s so weird. Look at that triangular head with giant eyeballs!

A mushroom, a hair, and a tiny phasmid exoskeleton, all caught in amber:

Show transcript:

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

Last month I released an episode about trace fossils, and listener Nicholas wrote me to suggest I also do an episode about amber—specifically, the animals and other items that were trapped in amber and preserved inside it when the amber fossilized. Nicholas also sent me lots of links to really interesting articles!

Amber is the term for fossilized tree resin. If you’ve ever climbed a pine tree and ended up with pine sap all over your hands, which is impossible to get off by just washing your hands and is super sticky and picks up every bit of dirt, you’ll have an idea of what amber starts out as and why it sometimes has insects and other stuff in it. Despite the name pine sap, it’s not actually sap. Sap is the fluid that carries nutrients around to a plant’s cells, sort of like plant blood. Resin is secreted by certain trees and other plants for various reasons, including to protect it from insect damage, to kill fungus, to seal off a broken branch or other injury, and to taste bad so herbivores won’t eat it.

There are different types of amber, because there are different plants that produce resin. We don’t always know what species of plant a particular type of amber comes from, since many are now extinct and can’t be directly studied. Conifer trees evolved around 300 million years ago but became really successful during the Mesozoic around 250 million years ago, spreading throughout the world and dripping resin all over the place. Conifers include pine trees, fir trees, hemlocks, yews, larches, junipers, cedars, redwoods, spruces, and lots of other trees and shrubs that are still widespread today. Some flowering plants, mostly trees, also produce resins. But before conifers evolved and outcompeted them, plants called medullosales lived around the world and produced resin too. Medullosales first appear in the fossil record around 360 million years ago and mostly died out around 298 million years ago. They’re all extinct now.

If your name is Amber, by the way, you are named for fossilized tree resin. That sounds gross, but amber has been prized for millennia as a gemstone. When polished, it can be a gorgeous yellow, gold, or brown, often the color of honey. But some amber is other colors, including red, blue, or green. It all depends on what tree originally produced the resin, its chemical makeup, and how it was fossilized.

So how does the resin fossilize? Sometimes it would drip onto the ground, become buried, and fossilize along with the ground around it. Sometimes the resin-producing tree would fall, become buried, and the resin inside would fossilize along with the wood. Sometimes the resin would drip into water, float to a quiet area or sink to the bottom of the pool or lagoon, and fossilize along with the sand and other sediment that covered it. This is why so much amber is found in the ocean, by the way. Once fossilized, amber floats in salt water—just barely, but enough that on some beaches it’s commonly washed up with the tide. People collect the pieces of amber to polish and sell. Amber can also be burned and often gives off a musky, piney scent that has been used in religious ceremonies.

The reason we’re talking about fossilized plant material in an animal podcast is that amber sometimes has insects or other small animals or animal parts inside it. This happened when it was still resin, which is really sticky. If an ant or bee was in the wrong place at the wrong time, it could be covered with resin and die. Then, if that particular dollop of resin ended up getting protected by sediment at just the right time, instead of weathering away and decaying it might fossilize over millions of years with the ant or bee or whatever inside it. And because the ant or bee was protected from air, water, and bacteria by the resin, and kept in place, the things found in amber are usually mostly intact and include parts of the body that ordinarily never fossilize. It may even help preserve DNA, which ordinarily decays after a matter of thousands of years, although there’s still conflicting evidence about whether this is the case. All this helps researchers study animals that went extinct millions of years ago almost as though those animals were still around.

Substances inside amber are called inclusions, whether they’re something exciting like a spider or just a piece of dirt. Well preserved inclusions, especially pretty ones like flowers, can make the piece of amber extremely valuable. If you want to buy polished amber with an inclusion, though, keep in mind that there are a lot of fakes out there. Make sure to have an expert examine an expensive piece before you spend money on it.

So let’s learn about some insects and other things that have been discovered in amber. I’m going to mention Myanmar repeatedly because it’s a big amber-producing region and the subject of an intensive ongoing study of animals found in the amber. Myanmar is in southeast Asia and was once called Burma.

The oldest organism found in amber are two tiny mites and a fly dated to 230 million years ago. The amber in question is very small, droplets no more than about six millimeters across, found in the Italian Alps. The mites are two different species, both new to science although they have living relations that resemble the ancient mites closely. Both of them ate plants. The fly isn’t as well preserved so researchers aren’t sure what species it was.

A 3 millimeter beetle found in amber dated to 99 million years ago was found in Myanmar. It’s an ancient relative of the modern flat rove beetle that lives under tree bark. But the flat rove beetle lives in South America, with one species from southwestern North America. Comparing the modern beetles with their ancestor gives researchers a closer idea of when the supercontinent Gondwana started to split apart into smaller continents as the landmasses moved slowly across the Earth to their current positions.

The amber found in Myanmar has yielded a lot of interesting information during recent studies. For instance, 450 millipedes! Not all in one piece, of course. The research team used a new type of analysis called micro-CT, which scans the inclusion and creates a highly detailed 3D image which can then be studied without damaging or even touching the amber. This is helpful when the amber pieces are privately owned and only on loan to scientists. Some of the millipede specimens were newly hatched, some fully grown, and include many species new to science.

Another insect found in Myanmar amber dated to 99 million years ago is so unusual that researchers placed it in its own order. To illustrate how rare this is, there are over a million insects described by scientists but they all fit into 31 orders. But now there’s 32 orders. The insect had a triangular head with big bulging eyes, a long flat body, long legs, and no wings. It also had glands on its neck that secreted chemicals that probably helped repel predators. Because of its large eyes and the unusual head shape, it could see almost all the way around it without turning its head. Two specimens of the extinct insect have been found in amber. One of the researchers who described the insect, amber expert and entomologist George Poinar, Jr, said that he thought it looked like an alien’s head so he made a Halloween mask that looked like it. As you do. He said “when I wore the mask when trick-or-treaters came by, it scared the little kids so much I took it off.”

It’s not just insects that are found preserved in amber. One foot and part of a tail from a 100 million year old gecko were found in amber about a dozen years ago. Researchers think the rest of the gecko was probably eaten, possibly by a dinosaur. Even though there isn’t a lot of the gecko to study, there’s enough to determine that it was a genus and species new to science, and that it was probably a juvenile gecko that would have grown up to a foot long if it had lived, or 30 cm. It was only about an inch long when it died, or a bit over two cm. It was stripey and had the same type of toe pads that modern geckos have that allow them to walk up walls.

Another foot, this one from a frog, was discovered in more of the Myanmar amber that’s the subject of ongoing studies. It was a tiny juvenile frog that lived in a tropical forest around 100 million years ago. It’s only the third frog ever found in amber, and is by far the oldest in addition to being the best preserved. Its skull, forelegs, part of its backbone, and the partial hind leg and foot are all preserved, together with a beetle. The problem is, some of the details researchers need to determine what kind of frog it is are missing, like the pelvis. They have just enough information to tantalize them since what they can see indicates that it might be related to some species of toad that live in temperate climates today, but not enough to tell for sure. You know they have to be tearing their hair out in frustration. Hopefully they’ll find another frog with all the bits and pieces they need.

Another surprise from the Myanmar amber is a baby snake only about two inches long, or 5 cm. At first researchers thought it was yet another millipede—I mean, when you’ve found 450 millipedes in amber you probably start to think everything is a millipede—but a scan determined that it was way different. It’s well preserved and even shows some features that modern snakes no longer have, like V-shaped bone spurs on the tail vertebrae that probably helped with stability when snakes first evolved to be limbless. Unfortunately the specimen is missing its skull.

Only one salamander has been found in amber, and it came from a surprising place. The amber was mined from the mountains of the Dominican Republic, which is in the Caribbean near Haiti. But there are no salamanders in the Caribbean today. The salamander in amber dates to around 25 million years ago and proves that salamanders did once live in the Caribbean. Not only that, the amber itself comes from an extinct tree that’s related to a tree native to East Africa. The salamander was a tiny juvenile that fell into a glob of resin after a predator bit one of its legs off. So, you know, it was doomed either way. Poor little salamander.

One really exciting discovery is part of an actual dinosaur tail trapped in amber. It came from a juvenile dinosaur that a scientist found at a market in Myanmar in 2015. The seller thought the tail was a plant, because—you’ll like this—it’s covered in FEATHERS that looked like bits of leaf. It’s dated to 99 million years ago. The feathers were chestnut brown on the tail’s upper surface and white underneath. They’re also very different from modern bird feathers. Researchers aren’t sure which dinosaur species the tail is from, but they do note that the dinosaur died, probably because it couldn’t get free from the resin. It wasn’t like some modern lizards that can drop their tails to escape predators.

Lida Xing, the same researcher who acquired the dinosaur tail in amber also managed to buy a bird in amber in the same Myanmar amber market. Only a few birds have been found in amber and they sell for ridiculous amounts of money—like half a million dollars—to private collectors. As a result, they’re rarely studied. Fortunately, Lida Xing was able to buy the bird in amber and it’s been studied ever since. It’s a young bird that was partially weathered away and squished after it died. It’s about 2 ½ inches long, or 6 cm, and is a type of primitive bird that went extinct at the same time as the non-avian dinosaurs 66 million years ago. It was dark brown and had teeth and clawed fingers on its wings, although both the beak and the finger-wings are missing from the specimen.

Sometimes marine or freshwater organisms are found in amber. For a long time no one understood how this happened, but in 2007 a team of researchers conducted a simple study to find out how it worked. One of the researchers owned some swampy property in central Florida. The team went there and cut pieces out of some pine trees growing in the swamp. Resin flowed from the trees’ injuries, down the trunk, and into the water. The researchers then collected the resin from the water and took it to a lab to examine it. They found water beetles, nematodes, small freshwater crustaceans, mites, even bacteria found in swampy water, all stuck in the blobs of resin. In other words, it’s not a bit unusual for water animals to get caught in resin. The unusual part is when they’re preserved in the resin long enough for the resin to fossilize into amber, and then the really rare part is when they’re found by a human who understands what they’re looking at and realizes it’s important.

Some of the most useful information preserved in amber concerns animal behavior. For instance, the recent discovery of a tick wrapped in spider silk. Spiders don’t usually eat ticks, but occasionally they do, and this tick in amber had been wrapped up in spider silk to immobilize it. Researchers aren’t sure whether the spider planned to eat the tick or was just stopping it from tearing up its web. Either way, it fell out of the web and plopped right into resin, which fossilized and was then found around 100 million years later. From this little piece of amber, we have direct evidence of a spider wrapping up its prey the same way they do today.

Another example is dated to 130 million years ago, when some green lacewing eggs hatched and the larvae and eggs were trapped in resin almost immediately. The green lacewing is a type of flying insect that’s still around today, although the ones found in resin are a species new to science. Since the babies were covered in resin during the act of hatching, researchers have learned a lot about how they emerged from the eggs.

There’s even a piece of amber dated to around 100 million years ago, also found in Myanmar, that shows a dragonfly with a missing head, together with the foot and tail of a tiny lizard. Researchers think the lizard may have caught the dragonfly and decapitated it to kill it, but before it could eat it, both predator and prey were trapped in resin. It’s too bad we don’t have the lizard’s head, because it would be really awesome if it had the dragonfly’s head in its mouth.

Some pieces of amber tell a story like this, like a photograph from millions of years ago. About 50 million years ago near what is now the Baltic Sea, a small mammal, possibly a rodent, bit a mushroom off at its base. A tiny insect, specifically a phasmid, or walking stick, was feeding on the mushroom and jumped away. All this happened just as a blob of resin dropped on the scene. The mammal fled, leaving behind a hair. The insect was trapped but was able to wriggle out of its exoskeleton in an early molt and escape, leaving its exoskeleton behind. The mushroom did nothing, because it was a mushroom. That particular phasmid species is now extinct, as is the mushroom species. Researchers don’t know much about the mammal. They know that the exoskeleton was literally shed moments before it was enveloped in resin because it still shows tiny filaments that would have crumbled away otherwise.

Even more dramatically, another piece of amber, again from Myanmar and about 100 million years old, shows a spider in the act of attacking a wasp. Both the spider, a bristly orb-weaver, and the parasitic wasp are still around today.

Other things are also preserved in amber, from pollen and plant spores to feathers and spiderwebs. It’s mined and gathered in various parts of the world for jewelry, so new amazing specimens could be discovered any day.

I could literally just keep going with this episode for hours talking about what’s been found so far, but I have to stop somewhere so I’ll leave you with one last amber inclusion.

It’s another strange insect new to science, also found in Myanmar amber dated to about 100 million years ago. It was tiny but really weird-looking. Researchers have been referring to it as a unicorn fly because it had a sort of horn sticking up from the top of its head that had three eyes at its tip. Researchers think its specialized horn with eyes on it gave it an advantage when flowers were tiny, as they were back in the early Cretaceous when it lived. Flowering plants had only recently emerged and were diversifying rapidly. It probably ate pollen and nectar. But when flowers evolved to be larger, it lost its evolutionary advantage and went extinct. It also had tiny mandibles that meant it could only eat very small particles of food, long legs, and weirdly shaped antennae.

The unicorn fly was described by our friend George Poinar, who described the weird insect with the triangular head too. And true to form, Dr. Poinar is up to his same tricks. He’s reported as saying that he was “thinking of making some masks based on it for Halloween.”

George, no! The children are frightened! Stop making Halloween masks!

One note about listener suggestions. I’ve been getting a lot of them lately, which is awesome, but I don’t necessarily use the suggestions in order. Which one I pick out for the next episode depends on a lot of things, including how much time I have for research, what strikes me as neat on any given day, and whether I can work a suggestion in to a planned episode about a larger topic. But I promise I do keep all suggestions in a list, and I will eventually get to them all! I’m always delighted to get more, too, so don’t feel like I’m telling you not to send any. Some of the best episodes I’ve done have been from listener suggestions, about animals I’d never heard of before.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

 

Episode 107: Ankylosaurus and Stegosaurus

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This week we’re going to learn about some armored dinosaurs, a suggestion by Damian!

I love that there’s a stock picture of an ankylosaurus:

Stegosaurus displaying its thagomizer:

Thagomizer explained:

Show transcript:

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

This week’s episode is another suggestion, this one from Damian, who wants to learn about armored dinosaurs like stegosaurus. It turns out that stegosaurus and its relatives are really interesting, so thanks to Damian for the suggestion!

We’ll start with ankylosaurus, which lived near the end of the Cretaceous period, right before all the non-avian dinosaurs went extinct, about 65 million years ago. A lot of paleontologists pronounce it ANKillosaurus, but it’s properly pronounced anKYlosaurus and for once, I’m finding the correct pronunciation easier, probably because it has the name Kylo right in the middle, like Kylo Ren of Star Wars.

There are a lot of species in the ankylosauridae family, but ankylosaurus was the biggest and is probably the one you would recognize since it’s a popular dinosaur. It’s the one with a big club on the end of its tail, but its leathery skin was studded with armored plates called osteoderms or scutes that made it look something like a modern crocodile. It also had spikes along its sides, although they weren’t as long or as impressive as some of the other ankylosaurids’ spikes.

We don’t know exactly how big ankylosaurus could get because we’re still missing some key bones like the pelvis, but paleontologists estimate it could grow around 33 feet long, or ten meters. Is legs were relatively short and its body wide, something like a turtle. When it felt threatened, it may have just dropped to the ground to protect its unarmored belly and laid there like a huge spiky tank.

Because we only have a few fossil specimens of ankylosaurus, there’s actually a lot we don’t know about it. Much of what we do know is actually mostly from ankylosaurus relatives. Researchers think ankylosaurus actually may not have been a typical ankylosaurid. They aren’t sure if the few fossils found mean it was a rare animal or if it just lived inland, away from water, since fossilization is much more common when water is involved. It lived in what is now North America, although it had relatives that lived throughout much of the world.

Ankylosaurus had a beak something like a turtle’s but it also had teeth that it probably used to strip leaves from stems before swallowing them whole. It probably ate ferns and low-growing shrubs. It had a massive gut where plant material would have been fermented and broken down in what was probably a long digestive process. But some researchers think it may have mostly eaten grubs, worms, and roots that it dug up with its powerful forelegs or its beak, sort of like a rooting hog. Its nostrils are smaller and higher on its nose than in other ankylosaurids, which could be an adaptation to keep dirt out. This might also explain why ankylosaurus appears different from other ankylosaurids, which definitely ate plants.

Ankylosaurus had a remarkably small brain for its size. Paleontologists think it may have used its massive tail club as a defensive weapon, but they don’t know for sure. The tail might just have been for display, or maybe males used their tail clubs to fight during mating season. It probably couldn’t walk very fast and was probably cold-blooded, which allowed it to survive after other dinosaurs went extinct after the big meteor struck. Eventually the plants it ate started going extinct, and since it was a big animal that needed a lot of food, it finally went extinct too. Researchers think bird ancestors survived because they were small and could live by eating plant seeds.

One interesting thing about ankylosaurs of all kinds is how they kept from overheating. Large bodies retain heat better than small bodies, which is why polar bears and mammoths are such chonks. Ankylosaurs were massive animals that lived in warm climates. New research published in late 2018 shows that they kept their brains cool by having extremely convoluted nasal passages with blood vessels alongside them. This helped cool the blood before it reached the brain, keeping it from overheating.

Ankylosaurus was related to stegosaurus. Stegasaurus lived in North America around 150 million years ago, during the Jurassic, but its ancestors were found in many other parts of the world. Like its cousin, stegosaurus had a small brain but grew to enormous size, as much as 30 feet long, or 9 meters. You definitely know what a stegosaurus looks like, since next to T rex it’s probably the most recognizable dinosaur. It had big dermal plates that stood up in rows along its spine and four spikes on the end of its tail, called a thagomizer. I’m not even making that name up, it really is called a thagomizer and the term really is from the Far Side cartoon. Its forelegs were shorter than its hind legs, and researchers think it probably stood with its head down to browse on low-growing vegetation, with its tail sticking up as a warning to any predator foolish enough to get too close.

The thagomizer spikes were probably used for defense. Not only do a lot of the spikes show injuries, we have a fossilized tail vertebra from an Allosaurus with a hole punched right through it. The hole matches the size and shape of a stegosaurus’s tail spike.

Paleontologists aren’t as sure about what the plates were for. They were made of bone covered with a keratin sheath that might have been brightly colored or patterned. There are signs that the plates contained a lot of blood vessels for their size, which suggests they helped with thermoregulation—that is, they might have helped the animal absorb and shed heat. Then again, new studies also suggest that the males had larger, broader plates while females had smaller, sharper ones. This argues that the plates might have been for display. Of course, they could be for both display and for thermoregulation.

Sometimes you’ll hear that stegosaurus had such a small brain that it had a second brain in the hip to help it control its tail. This isn’t the case, though. There is a canal in the stegosaurus’s hip near the spinal cord, but this is something found in other dinosaurs and in modern birds. In birds it’s where a structure called the glycogen body is, but researchers don’t actually know what the glycogen body is for. That’s right, something present in all birds, even chickens and pigeons, is more or less still a mystery to scientists. But whatever it is, it’s not a second brain.

There are other mysteries associated with the stegosaurus, like how it ate. It had a tiny head for its size, about the size of a dog’s head, with peglike teeth that seem to have been used for chewing or shearing plant material. But because the head was so small, and the teeth weren’t shaped for grinding, it probably couldn’t have chewed its food up like modern grazing mammals do. But it also doesn’t seem to have ingested gastroliths, small stones used for grinding up food in the stomach.

There were lots of other armored dinosaurs, generally related to stegosaurus and ankylosaurus. I was going to talk about triceratops too, but technically it didn’t have armor, just head frills and horns. Besides, I think triceratops and its relations need their own episode pretty soon. So we’ll finish up with another ankylosaurid, Akainacephalus.

The only fossil we have of akainacephalus was discovered in 2008 in Utah. It’s a remarkably complete fossil, including the skull and jaws, and has been dated to around 76 million years old. It had a spiky ridge over its eyes and short triangular horns on its cheeks that pointed downward. It also had a tail club that ankylosaurids are known for.

Akainacephalus was formally described in 2018 as not just a new species of ankylosaurid, but one in its own genus. Even though it was found in North America, researchers have determined that it’s more closely related to the ankylosaurids that lived in Asia.

Before Akainacephalus evolved, Asia and North America were connected with a land bridge due to low sea levels. This land bridge is called Beringia, and while it’s currently underwater, at different times in the past it’s been exposed and allowed animals to cross from Asia to North America and from North America to Asia. Beringia is about 600 miles wide, or around 1,000 km, when it’s above water. At the moment, it’s represented by a couple of little islands in the shallow Bering Strait, since it’s been underwater for the last 11,000 years.

Previously researchers thought this land bridge had only been open once during the Cretaceous, but that was before paleontologists examined akainacephalus. Since akainacephalus is related to ankylosaurids that lived in Asia after the land bridge was submerged, it’s possible there was a second opening of Beringia that allowed akainacephalus’s ancestor to migrate from Asia to North America.

That’s one of the really neat things about science. You start by looking at a cool spiky fossil skull, and you end up learning something new about how deep the oceans were 80-some million years ago.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 106: Domestication with and without foxes

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Thanks to M Is for Awesome, who suggested the topic of domestication! This week we look mainly at foxes and how they relate to the domestication of dogs. Also, chickens.

Unlocked Patreon episode about chicken development and domestication: https://www.patreon.com/posts/21433845

A red fox:

Domestic foxes want pets and cuddles also coffee:

The fennec fox with toy I JUST DIED:

The raccoon dog is actually a species of fox:

Show transcript:

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

Back in episode 80, about mystery dogs and other canids, I said I was going to leave foxes for another episode. And here it is! But as I researched, it turned out that while there are lots of interesting foxes, they’re all pretty similar overall. So while we will learn about some of the more unusual foxes this week, I’m mostly going to talk about how animals are domesticated by humans. This is a suggestion from M Is for Awesome, who suggested domestication “and how it changes domesticated creatures from their wild cousins.” You may not know how this relates to foxes, in which case, I’m about to blow your mind.

But first, we should learn about how scientists think other canids became domesticated. You know, how dogs became dogs instead of wolves.

Domestication of wolves took place possibly as much as 40,000 years ago, but certainly at least 14,000 years ago. Gray wolves are the closest living relative of the domestic dog, but the gray wolf isn’t the dog’s ancestor. Another species of wolf lived throughout Europe and Asia, possibly two species, and domestication of these wolves occurred at least four different times in different places, according to DNA studies of ancient dog remains.

One of the oldest dog remains ever found dates to 33,000 years ago, found in a cave in Russia. Researchers think it wasn’t fully domesticated, but was probably connected with the people who had been using the cave as shelter. A 2017 study concluded that it isn’t related to any modern dogs and apparently was related to a species of wolf that has since gone extinct.

Many researchers think that wolves actually started the domestication process. Wolves hunt but they also scavenge, so they may have gotten into the habit of following bands of humans around to find scraps of food. Back in the hunter-gatherer days before we started growing crops, humans were nomadic, moving from place to place to find food. Wolves would have been attracted to the bones and other parts of dead animals humans left behind. If a wolf got too close to a campfire where humans were sitting around eating, two things might happen. If it was an aggressive wolf, the humans would chase it away or even kill it. But if it wasn’t aggressive, maybe because it was scared or young, a human might have tossed it a little bit of meat or a bone. That wolf would definitely hang around more, hoping for more food. If the humans grew used to it, it might even have started to consider itself part of the human’s pack. And if another predator approached, the wolf might growl at it and warn the humans, who would reward the wolf with more food. Over the generations, the wolves who got along best with humans would receive the most food and therefore be more likely to have babies that also got along with humans. It’s a lot easier to act as a camp guard and be given food and pets than it is to go out and try to kill ice age megafauna with your teeth.

Remains of a puppy dated to 14,000 years ago was found recently in a prehistoric grave in Germany. A test of its DNA indicates that it is related to modern dogs. The puppy was fully domesticated, well cared for, and had been buried with a man and a woman. Researchers can even tell that the puppy died of distemper, which leaves telltale marks on the teeth. The puppy had survived until the disease was well advanced, and it could only have done so with special care from humans. Even today distemper is a terrible disease among dogs. I had a puppy that died of it when I was little. Obviously, even 14,000 years ago dogs were already more than working animals or camp scavengers. Someone loved that puppy and tried to help it get better.

An interesting thing happens with domestication. Certain physical traits come along with the behavioral traits of reduced aggression and willingness to treat humans as surrogate parents. In the case of dogs, these often include a puppy-like appearance, including floppy ears, curled tail, smaller adult size, and a rounder head with smaller jaws. This isn’t the case with all dog breeds, of course, but the changes seem to be genetically linked to behavior. It’s called domestication syndrome.

So this is interesting, but how does it apply to foxes? Foxes are canids, but they aren’t all that closely related to dogs.

Well, in 1959 a Russian zoologist named Dmitry Belyaev decided to see if he could domesticate foxes. Taming and domestication are different things. A wild animal that has become used to certain humans can be considered tame, but a domesticated animal is one that is genetically predisposed to treat humans as caregivers. Belyaev didn’t just want to tame a few foxes, he wanted to try actually domesticating them.

He started his project by going to a fur farm that bred foxes to kill for their furs, which were then made into coats and other clothing. These were red foxes, which are common throughout much of the world, but because they were bred for their fur, they weren’t red. They were a darker color called silver, a color mutation, but other than that they were regular foxes. Belyaev chose foxes by how well they tolerated people, the ones that were less likely to bite.

He bred these foxes and when the babies grew up, he chose the least aggressive ones to breed. Then he chose the least aggressive babies from those parents, and so on. And after only six generations, he started to see results. Some of the foxes in the sixth generation actively sought out humans. They licked their hands, whined for attention, and even wagged their tails.

Something else happened too. The foxes started showing physical differences. Some had fur with white patches or various other color variations, some had floppy ears, some carried their tails so that the tip pointed up. All these traits are common in dogs, but pretty much never seen in wild foxes. Recent research shows that the changes are genetic and linked to lower adrenaline production. One color of fox, called Georgian white, has never been seen except in Belyaev’s domesticated foxes. It’s a lovely white all over with black ears and black or gray markings on the face and paws.

In case you’re wondering how much of the behavioral differences are due to increased human contact, the study also breeds the least tame foxes. They continue to look and act like wild foxes.

The breeding project has continued even though Belyaev died in 1985. These days almost all the foxes are as tame as dogs. Belyaev also conducted domestication projects with rats and American mink, both of which succeeded as well as the fox project. But if you want a pet fox, you’re out of luck. The foxes are occasionally for sale, but they’re extremely expensive and some parts of the world don’t allow foxes to be kept as pets at all, even these domesticated foxes. Occasionally someone will pop up online claiming to have some of the domesticated foxes for sale, but they always disappear after taking people’s money and never deliver any foxes.

Besides, even though Belyaev’s foxes are domesticated, they aren’t dogs. They don’t always behave in ways that make sense to humans. Humans and dogs have been buddies for untold thousands of years and we’ve basically evolved together, while foxes have only been domesticated for basically one human lifetime. One zoologist whose institute has several of the domesticated foxes for study and outreach says that she has to watch her coffee cup because if she doesn’t, one of the foxes might pee in her coffee. As soon as I read that, my desire to own a pet fox diminished. They’re really cute, but so are dogs, and while I have had a dog that would steal and eat sticks of butter off the counter, I never had to worry about him peeing in my coffee. Besides, the domestic foxes are also hard to house-train and still retain a wild fox’s musky odor.

The fennec fox is the smallest canid, and it’s sometimes kept as a pet, but it’s not domesticated. If the babies are taken from their mother very early, they grow up fairly tame, but they’re still wild animals and can be aggressive.

I have seen a fennec fox at the Helsinki Zoo! It was adorable. I definitely can see why people want one as a pet, but honestly, cats are about the same size and shape but are a lot less likely to bite. Also, cats purr. The fennec fox lives in northern Africa and parts of Asia and its fur is a pale sandy color with a black tip to the tail. Its eyes are dark and its ears are large. It stands only about 8 inches tall at the shoulder, or 20 cm, but its ears can be six inches long, or 15 cm. It eats rodents, birds and their eggs, insects, and other small animals, as well as fruit. It can jump really far, some four feet in one bound, or 120 cm. Because it lives in desert areas, it rarely needs to drink water. It gets most of its water through the food it eats, and researchers think it may also lap dew that gathers in the burrow where it spends the day.

The most common species of fox is the red fox. Foxes are canids related to dogs and wolves, and just to be confusing, male foxes are sometimes called dogs. Female foxes are vixens and baby foxes are cubs or kits. But the red fox isn’t the only species out there, not by a long shot.

For instance, the grey fox lives throughout North and Central America. It can look a lot like a red fox but its legs are always reddish or tan, unlike the red fox, which always has black legs. Instead of a white tip to its tail like red foxes have, the grey fox has a black tipped tail. It’s also not that closely related to the red fox or any other foxes, for that matter. Its pupils are rounded like a dog’s instead of slit like other foxes, which have eyes that resemble cats’ eyes.

The grey fox also has hooked claws that allow it to climb trees. That’s right. I said it can and does climb trees just like a cat. It’s nocturnal and omnivorous, which means it eats pretty much anything. It especially likes rabbits and rodents, but it also eats lots of fruit and insects.

The only other canid that can climb trees is the raccoon dog, which is neither a raccoon nor a dog. It’s actually a type of fox, but it does look a lot like a raccoon at first glance. It has grizzled brown-gray fur, a black mask over the eyes and cheeks, and a short muzzle and rounded ears. And, of course, it also climbs trees like a raccoon. But it’s larger and bulkier than a raccoon with much longer legs, and its tail isn’t ringed like a raccoon’s tail.

The raccoon dog is native to parts of Asia, but it was introduced to parts of western Russia in the early 20th century as a fur animal and is now widespread throughout much of Europe. It’s an omnivore too; pretty much all foxes are omnivores. It eats rodents, frogs and toads, birds, fish, fruit and plant bulbs, some grains, and insects. You know, pretty much anything. It even eats toads that are toxic to other animals, diluting the toxins with massive amounts of saliva. And in cold areas, the raccoon dog hibernates. It’s the only canid that does.

Several months ago, I released a Patreon episode about chicken teeth that also talked about the domestication of chickens. It wasn’t my best episode but it’s relevant here so I went ahead and unlocked it for anyone to listen to. There’s a link in the show notes so you can click through and listen in your browser without needing a Patreon login or anything. Anyway, let’s finish up today with some information I just learned about the domestication of chickens. Specifically, a breeding project similar to the Belyaev foxes but with the wild birds that are the ancestors of domesticated chickens.

The bird is called the red jungle fowl, which lives in Asia and looks like a chicken, but is smaller than domesticated chickens. It was domesticated as long as 8,000 years ago but the wild bird still exists. A Swedish research team tried replicating Belyaev’s domesticated fox experiment with some of the wild birds. Like the foxes, the researchers bred a population of birds that were just ordinary wild jungle fowl and not selected for tameness, and a population of birds that were chosen because they tolerated humans a little more than usual. As each of the baby birds grew up, they were tested by having a human walk into the pen and try to touch it. The human wasn’t told whether the bird was from the tame group or the wild group. But after a couple of generations, it was obvious which was which. The tame birds became so tame that they didn’t mind the human at all.

And like the foxes, although the only trait the researchers selected for was tameness, the chickens began to change in other ways too. They became bigger and the hens laid more and larger eggs. This happened within only a few generations, which suggests that domestication is a much faster process than researchers once assumed.

And thanks to recent study, we’re pretty sure we know why these physical changes happen along with the behavioral changes. Selecting for tameness alters the genes that controls what are called the neural crest cells. When the embryo is developing, the neural crest cells migrate to different parts of the body. They affect the coat or feather coloring and some other physical developments, but they also affect the development of many other traits, including the fight-or-flight response. In other words, if you select for an animal that tends to be calm instead of fighty or flighty, you’re also accidentally selecting for differences in physical traits. Follow-up studies confirm that neural crest cells migrate differently in domestic animals than they do in their wild counterparts.

Research into domestication is a hot area of study right now, now that DNA and molecular genetics studies are more sophisticated. You know, in case anyone out there is considering a career in science.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 105: The Hagfish and the Sea Spider

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This week’s episode is about two strange animals of the sea: the hagfish, which isn’t a fish, and the sea spider, which isn’t a spider.

A curled-up hagfish:

The sea spider is actually quite pretty as long as I don’t have to touch it:

Show transcript:

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

A long long long time ago, and I can’t even remember which episode it was, I mentioned that one day I would do an episode about the hagfish because it’s such a weird animal.

Well, that day is today.

The hagfish isn’t a fish. It looks more like an eel and is sometimes called a slime eel. But it’s not an eel either. In fact, it’s so weird that scientists are still trying to figure out exactly where the hagfish fits in the animal world.

The only living animal that is similar to the hagfish is the lamprey, and current research suggests that they are fairly closely related. We talked about the sea lamprey way back in episode three.

There are a number of hagfish species. The biggest is the goliath hagfish (Eptatretus goliath), which can grow more than four feet long, or 127 cm, but most species are much smaller. As mentioned, it looks sort of like an eel, with a tail that’s flattened like a paddle. It doesn’t have true fins, it doesn’t have a jaw, and it only has a single nostril. It usually breathes by swallowing water, which runs through gill pouches inside the body, but some researchers think it can also absorb oxygen through its skin. It can survive for hours without oxygen.

The hagfish is considered a vertebrate because it has a rudimentary spine, called a notochord. It has eyespots instead of true eyes, which can only detect light, but fossilized ancestors of living hagfish seem to have had more complex eyes. I guess they just didn’t need them.

The hagfish has a lot of blood for its size. Its skin is loose and only attached to the rest of the body along its back and at its slime glands. Since its skin is thick and contains about a third of the body’s blood, the hagfish actually looks kind of like a fluid-filled sock with a tail. If you’ve ever bought an eelskin wallet or other item, it was probably actually made from hagfish skin. Because the hagfish has such low blood pressure, the lowest recorded in any animal, and because its skin is so loose and it only has a few bones, it can squeeze through incredibly small openings. When it does, the blood in its skin is pushed into the rear of its body. This would kill an ordinary animal, but it doesn’t affect the hagfish at all.

There’s so much weirdness about the hagfish that it’s hard to know where to start. Its mouth, for instance. Instead of jaws, its skull has a piece of cartilage that can move forward and backward, with two pairs of comb-shaped teeth attached to the plate. This sounds like it would be an awkward way to bite into food, but it works so well for the hagfish that it hasn’t changed in some 300 million years. It’s more like a toothed tongue or a radula than anything resembling vertebrate jaws. The hagfish also has short tentacles around its mouth.

The hagfish eats anything, but the main part of its diet is probably marine worms that live on the sea floor. It also scavenges carcasses that sink to the bottom of the sea. If you’ve seen that amazing time-lapse video of a blue whale carcass, you’ve seen hagfish. They’re the ones that burrow into the carcass to bite pieces of meat off from the inside, and the ones that will actually tie their body into a knot to help yank food off the carcass. Since the hagfish lives on or near the sea floor, trawlers who drag nets along the sea floor to fish often catch hagfish by accident. Sometimes they catch so many hagfish that by the time they haul the net up, the hagfish have eaten all the fish in the net.

But the hagfish also hunts fish actively, especially the red bandfish that lives off the coast of New Zealand. The red bandfish digs a burrow, and the hagfish will slither into the burrow and drag the fish out to eat it. It may actually suffocate the fish first by smothering its gills with slime.

And that brings us to another weird thing about the hagfish, its slime. The hagfish is famous for its slime. It has something like a hundred slime glands along its sides, and if it feels threatened it will release massive amounts of slime through the glands. It only takes a fraction of a second to release slime. This doesn’t just make it slippery, the slime actually absorbs water and increases in volume, and it’s sticky. If a fish grabs a hagfish, suddenly the hagfish has secreted more than five gallons of slime—that’s 20 liters—which contains thin fibers that help clog the fish’s gills. Meanwhile, the hagfish will tie itself into a knot and push the knot from its head to its tail, which pushes the slime off of its own body and leaves it behind. The hagfish swims away, leaving the predator dealing with copious amounts of slime sticking to its gills. Basically, almost nothing eats the hagfish, not even sharks. But exuding so much slime does cost the hagfish energy. It can take weeks to recover.

One really interesting thing about hagfish slime is those fibers that make up part of its volume. When dried out, the fibers look like silk and are almost as strong and thin as spider silk. They’re also produced from cells that are genetically smaller than those in spiders. Researchers are trying to figure out how to take the DNA for hagfish fiber production and implant it into bacteria that would then produce quantities of silk. Because it’s so strong and lightweight, the silk could then be used to make cloth that could take the place of petroleum-based fibers like nylon. This is so exciting. My guess is it’ll be marketed as eel silk, because that sounds way better than hagfish slime fibers.

We don’t have many hagfish fossils since the hagfish only has a few bones and the rest of its body is rarely preserved in the fossil record. But we do have one really good fossil dated to 100 million years old. Recently, it was imaged using a method called synchrotron scanning, which identifies chemical traces of soft tissues left in the stone. The scan revealed the chemical signature of keratin along the fossil’s sides, and since the slime fibers are made of keratin, researchers think that 100 million years ago the hagfish was already producing slime.

An interesting side note about the synchrotron scanning is that it can be used to detect glue or paint used to make a fossil look more complete than it really is. Fossil forgers beware.

Researchers still don’t know a lot about how hagfish reproduce. We do know that hagfish eggs take a long time to hatch, something like eleven months. The eggs have hooked hair-like structures at the ends and usually stick together in bunches. Hagfish don’t hatch into larvae like lampreys do, but instead hatch into little hagfish. Some hagfish species appear to be hermaphroditic, which means an individual contains both eggs and sperm, but they probably don’t lay eggs until they’re older.

The hagfish also has three hearts. Happy Valentine’s Day.

Another weird and fascinating ocean creature is the sea spider. Honestly, despite its name, after the hagfish, the sea spider seems positively normal.

The sea spider isn’t actually a spider, but it’s also not a crab. Like the hagfish, researchers aren’t sure where the sea spider belongs taxonomically. Traditionally it’s been grouped with the group of arthropods known as chelicerata [kelisserate-a], which includes true spiders, scorpions, ticks, and their relatives, and horseshoe crabs. But some researchers think the sea spider is more closely related to our old friend Anomalocaris, a stem arthropod that lived during the Cambrian. Recent genetic studies so far indicate that the traditional chelicerata classification is probably correct.

The sea spider has four pairs of legs, although a few species have five or six pairs of legs instead. Some species have one or two pairs of simple eyes, but other species have no eyes at all. The body is quite small in relation to the legs, which are extremely long, which means the digestive tract is actually partly in the legs, because the body is too small for it. It walks along the bottom of the ocean or may swim by pulsing its long legs like a jellyfish with legs instead of a bell. In species that swim, the legs may be lined with long bristles. Males take care of the eggs until they hatch, so male sea spiders have a pair or two of small legs called ovigers that are used to carry eggs.

Like true spiders, the sea spider doesn’t breathe in a way we think of breathing. It absorbs oxygen through pores in its exoskeleton, and the oxygen is then absorbed into a substance called hemolymph. This is basically invertebrate blood. The hemolymph is moved around its body to the cells that need it—not by its heart, which is relatively weak and only moves hemolymph around the small body, but by the digestive system. Since the digestive system goes all the way down into the legs and already moves digestive fluids around, that makes sense.

Some species have mouthparts, but most eat using a proboscis that it uses to suck hemolymph and other fluids out of its prey. Some species have spines at the tip of the proboscis. It sticks its proboscis into a sponge, worm, jelly, sea anemone, or other invertebrate, injects digestive fluids that liquefy the surrounding tissues, and slurp the fluids up. Sometimes this kills the prey animal, sometimes it doesn’t.

Sea spiders live throughout the world’s oceans and there are well over a thousand known species. Most are small and live in shallow water, but a few live in water up to 23,000 feet deep, or 7,000 meters. The biggest species live in the cold waters around Antarctica, with the very largest individual ever found having a legspan of about 27 inches, or 70 cm. So no, they’re not dangerous to humans at all and while they may look scary because those legs are so long, they’re harmless unless you happen to be a soft-bodied invertebrate that can’t run away.

That doesn’t mean there aren’t actual spiders that live in the ocean. Marine spiders are actual spiders, and they’re intertidal, which means they live in the typically small area between high tide and low tide. During high tide they hide underwater in shells, coral, or plants, and they can breathe because they build air chambers from silk. When the tide goes out, the spiders run onto the sand and hunt small insects and other invertebrates. A new species of marine spider was discovered in Queensland, Australia in 2009 that grows to almost 9 mm in size. That’s almost a centimeter long, or half an inch! Males are smaller, though. It was named Desis bobmarleyi after the Bob Marley song “High Tide or Low Tide.”

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 104: Tiger Salamanders

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Thanks to Connor who suggested this week’s topic, tiger salamanders! Not only do we learn all about the Eastern tiger salamander and the banded tiger salamander, we also learn where asbestos comes from AND IT’S NOT EVEN LIKE I GOT OFF TOPIC, I SWEAR

The Eastern tiger salamander:

The barred tiger salamander:

A baby tiger salamander:

A CANNIBAL BABY TIGER SALAMANDER:

Show transcript:

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

This week we’ll learn about an animal suggested by listener Connor that’s been waiting on the ideas list for way too long. Thanks, Connor! Sorry it took me so long to get to your suggestion!

So, Connor suggested that we cover “tiger salamanders’ cannibalism and how salamanders were once believed to be fire-related.” That sentence gives us a lot to unpack.

First let’s find out what a tiger salamander is. It gets its name because it’s stripey, or at least has blotches that can look sort of like stripes. It may be yellow and black or green and black. It grows up to 14 inches long, or 36 cm, which is pretty darn big for a salamander. Smaller tiger salamanders mostly eat insects and worms, but the bigger ones will naturally eat bigger prey, including frogs.

Like all salamanders, the tiger salamander is an amphibian. That means it’s cold-blooded with a low metabolic rate, with delicate skin that needs to stay damp. Like other salamanders, it doesn’t have claws, it does have a tail, and its body is long compared to its short legs. Basically a salamander usually looks like a wet lizard. But salamanders actually have more in common with frogs than with lizards, since frogs are also amphibians.

While the tiger salamander can swim just fine, it spends most of its adult life on land. It catches insects by shooting its sticky tongue at them just like frogs do. And just like a frog, the tiger salamander’s eyes protrude like bumps on its head, and it retracts its eyeballs when it swallows to help force the food down its throat. This is fascinating, but you might want to take a moment to be glad you don’t have to do this every time you swallow a bite of food.

The tiger salamander, like most other amphibians, secretes mucus that helps its skin stay moist and tastes nasty to predators. The tiger salamander doesn’t appear to actually be toxic, though. It mostly lives in burrows it digs near water, and while it’s common throughout much of eastern North America, it’s not seen very often because it’s shy and because it prefers ponds in higher elevations such as mountains.

A female lays her eggs on the leaves of water plants in ponds or other standing water. The eggs hatch into larvae which have external gills and a fin that runs down its back and tail to help it swim. At first the larva looks a little bit like a tadpole, but it grows legs soon after hatching. As a larva, it eats aquatic insects and tiny freshwater crustaceans like amphipods. How soon it metamorphoses into an adult salamander depends on where it lives. Tiger salamanders that live in more northerly areas where summer is short will metamorphose quickly. Tiger salamanders that live in warmer climates stay larvae longer. And in areas where the water is better suited to gathering food than the land is, the larvae may not fully metamorphose at all and will live in the water their whole lives. The term for a fully adult salamander that still retains its external gills and lives in the water is neotene, and it’s pretty common in salamanders of various species.

The tiger salamander is actually closely related to the axolotl, more properly pronounced ash-alotl. I learned that from the Varmints! podcast. Most axolotls are neotenic. On the rare occasion that an axolotl metamorphoses into its adult form, it actually looks a lot like a tiger salamander.

Unfortunately, the tiger salamander carries diseases that can kill frogs, reptiles, fish, and even other amphibians, even though the tiger salamander is usually not affected. The tiger salamander is also a popular pet, but since many pet tiger salamanders were caught in the wild, be careful that you’re not introducing diseases that might kill your other amphibians, reptile, or fish pets. While the tiger salamander is doing just fine in the wild and isn’t protected, it’s always better to buy pets from people who bred the salamanders and can guarantee they’re disease free. Likewise, if you’re someone who likes to fish, don’t use tiger salamander larvae as bait. Researchers think this is the main way the diseases carried by tiger salamanders spread.

So all this information about tiger salamanders is interesting, but it’s also pretty normal for salamanders. What does Connor mean by cannibalism in tiger salamanders?

The tiger salamander we’ve just learned about is actually called the Eastern tiger salamander. Until recently the barred tiger salamander was considered a subspecies of the Eastern tiger salamander, although now it’s considered a separate species. It looks and acts pretty much just like the Eastern tiger salamander but it lives in the western areas of North America. The main difference between the two species is that the barred tiger salamander is not quite as big, and it isn’t as common. The adults are illegal to sell in most American states, although it’s legal to keep them as pets.

But there is one main difference about the barred tiger salamander, and it’s something that only happens in some populations, usually ones in dry areas where ponds are more likely to dry up and larvae need to metamorphose quickly as a result. A few weeks after they hatch, some of the larvae develop large teeth and wider heads. Then they start eating other tiger salamander larvae. Researchers have found that a cannibal tiger salamander won’t eat tiger salamanders it’s related to, and the hypothesis is that it recognizes the scent of its brothers and sisters.

Researchers think most tiger salamanders don’t become cannibals because doing so increases the risk that it will be affected by the diseases tiger salamanders carry. By eating salamanders that are competing for the same resources its siblings need to grow up quickly, the cannibal salamanders help their siblings and may sacrifice themselves by risking disease as a result.

Forget what I said about being glad you don’t have to retract your eyeballs every time you swallow. Just be glad you’re not a tiger salamander at all.

Connor also mentioned the old belief that salamanders lived in fire. How the heck did that belief come about? Salamanders are wet little amphibians that mostly live in water.

It’s been a belief for literally thousands of years. It’s mentioned in the Talmud, in Pliny the Elder’s writings, and in bestiaries. Where did it start?

The main hypothesis is that because some salamanders hibernate in rotting logs, the only time most people would see a salamander would be when they tossed firewood into a fire. The salamander, rudely awakened from its winter home, would slither out of the fire, protected from the heat for a very brief time by its damp skin. There’s actually a species of salamander common throughout Europe called the fire salamander. So that sounds plausible. Older legends refer to the salamander actually being able to put fires out with its cold body or breath. Since salamanders are cold-blooded and damp, they do feel cold to the touch even on relatively warm days.

One traditional writer thought all this was pish-posh, though. Marco Polo himself, who traveled widely in Asia starting in 1271, wrote, “Everybody must be aware that it can be no animal’s nature to live in fire.” He was right, of course. Nothing lives in fire. But by the time Marco Polo lived, there was a certain amount of confusion regarding a type of cloth that was fire-resistant. It was called salamander wool and was supposed to be woven from hairs harvested from salamanders—which is a real trick, considering only mammals have hair.

Marco Polo met a man from Turkey who procured the fibers that were called salamander wool. But they didn’t come from an animal at all. He had to dig for them. I’ll quote from a translation of Marco Polo’s writing:

“He said that the way they got them was by digging in that mountain till they found a certain vein. The substance of this vein was then taken and crushed, and when so treated it divides as it were into fibres of wool, which they set forth to dry. When dry, these fibres were pounded in a great copper mortar, and then washed, so as to remove all the earth and to leave only the fibres like fibres of wool. These were then spun, and made into napkins. When first made these napkins are not very white, but by putting them into the fire for a while they come out as white as snow. And so again whenever they become dirty they are bleached by being put in the fire.

“Now this, and nought else, is the truth about the Salamander, and the people of the country all say the same. Any other account of the matter is fabulous nonsense.”

This actually sounds even more confusing than fire salamanders. What the heck is this cloth, what are those fibers, are they really fireproof, and if so, why hasn’t anyone these days heard of it?

Well, we have, we just don’t realize it. That stuff is called asbestos.

I always thought asbestos was a modern material, but it’s natural, a type of silicate mineral that’s been mined for well over 4,000 years. It’s actually any of six different types of mineral that grow in fibrous crystals. Just like Marco Polo reported, after pounding and cleaning, you’re left with fibers that really are fire, heat, and electricity resistant. As a result, it became more and more common in the late 19th century when it was used in building insulation, electrical insulation, and even mixed with concrete. And just as Marco Polo reported, it was still spun into thread and woven into fabric that was often made into items used around the house, like hot pads for picking up pans from the oven, ironing board covers, and even artificial snow used for Christmas decorations.

Of course, we know now that breathing in bits of silica is really, really bad for the lungs. The dangers of working with asbestos had already started to be known as early as 1899, when asbestos miners started having lung problems and dying young. The more asbestos was studied, the more dangerous doctors realized it was—but since it was so useful, and the effects of asbestos damage on the lungs usually took years and years to manifest, businesses continued to ignore the warnings. Asbestos was even used in cigarette filters during the 1950s, as if smoking wasn’t already bad enough.

These days, most uses of asbestos have been banned around the world, but if you’ve seen those TV commercials asking if you or someone you know suffers from mesothelioma, and you might be entitled to compensation, that’s a disease caused by breathing in asbestos dust. Some industries still use asbestos.

It sounds like asbestos being called salamander wool was named not because people literally thought they were made from hairs harvested from salamanders but because asbestos cloth resisted fire and heat the way salamanders were supposed to. These days chefs use a really hot grill called a salamander to sear meats and other foods, which is named after the folkloric animal, but no one believes it has anything to do with real salamanders. At least, I hope not. Then again, there are pictures of salamanders in medieval bestiaries showing salamanders with hair, which argues that at least some people really truly believed that asbestos came from salamanders.

Because tiger salamanders are large and not endangered, they’re good subjects for study. Researchers have learned some surprising things by studying the behavior and physiology of tiger salamanders. For instance, salamanders in general have legs that haven’t changed that much from those of the first four-legged animals, or tetrapods. Researchers study the way tiger salamanders walk to learn more about how early tetrapods evolved. And yes, this research did involve filming tiger salamanders walking on a tiny treadmill.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 103: Trace Fossils

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You may know what fossils are (I hope), but have you heard of trace fossils? You have now!

A giant ground sloth footprint with a human footprint inside it, made some 11,000 years ago:

Climactichnites:

A “devil’s corkscrew”:

A Paleocastor fossil found at the bottom of its fossilized burrow:

Stromatolite:

Coprolites:

Gastroliths found with a Psittacosaurus:

Show transcript:

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

This week we’re going back in time to look at fossils, but these aren’t regular fossils. They’re called trace fossils, or ichnofossils. Instead of fossilized bones and other body parts, trace fossils are records of where organisms were and what they were doing.

Fossil footprints are one of the most common trace fossils. We have lots of dinosaur footprints, and from them we know that dinosaurs held their tails off the ground, that some dinosaurs traveled in herds with the young in the middle, and things like that. A fossil footprint is formed when an animal steps in soft mud or sand, usually near water, and the resulting footprints were covered with sediment which then dried, protecting the footprints. If the footprints continued to be protected from water and other processes that might wipe them out, over the years more and more sediment was deposited on top, eventually compacting it so that pressure and chemical reactions within the sediment turned it to stone. This is why we sometimes have two impressions of the same footprints: the actual footprints and a cast of the footprints made by the sediment that filled them initially.

The White Sands National Monument in New Mexico has so many footprints of so many animals around what was once a lake that it’s referred to as a megatrack. Seriously, we’re talking hundreds of thousands of footprints. In 2014 a team studying the tracks found a set of ancient human footprints, the first ones found in the park. But while the tracks were well preserved, the team couldn’t pinpoint how old they were. They invited other researchers to come examine the prints to help date them.

In 2016 a British paleontologist named Matthew Bennett came to examine the prints, but while he was there, he took a look at some giant ground sloth prints nearby. And when he did, he made an amazing discovery. There was a sloth footprint with a human footprint on top of it, actually within the sloth’s footprint. The sloth’s print was 20 inches long, or almost 51 cm. And after that, the next sloth footprint also had a human footprint in it. And after that another. And another. And another. Ten sloth footprints in a row had human footprints inside.

Since the tracks were made in sandy lake mud and both tracks were reasonably clear, the researchers determined that the tracks were probably left on the same day. In other words, the human was probably trailing the sloth.

But that’s not all. Bennett and the other scientists at the site followed the tracks of both sloth and human and found marks where the sloth turned around and reared on its hind legs to face the approaching human. And there are more human prints that approach at a different angle—not just human prints, but prints that suggest the human was actually tip-toeing.

The most likely explanation is that the humans were hunting the sloth, with one human getting its attention while a second crept up behind it. But we don’t know for sure. One odd thing is that the human trailing the sloth actually had to stretch to step inside each sloth print. Even small giant ground sloths were enormous, nine or ten feet long, or about three meters, with long curved claws. Ground sloths were plant-eaters that used their claws to strip leaves from branches and dig giant burrows, but the claws made formidable weapons too. It’s possible that the ancient human was just amusing himself by stepping exactly in the sloth’s prints.

Since this initial finding, researchers have found more sites where sloths appear to have turned to face an aggressor, possibly humans. The age determined for the prints, around 11,000 years old, corresponds with the time that giant ground sloths went extinct in North America. Researchers have long suspected that humans hunted them to extinction, and now we may have some direct evidence that this happened.

But fossil footprints aren’t just of big animals. Small squidgy ones leave footprints too, or trails that show where an animal traveled even if it didn’t actually have feet. For instance, 510 million years ago, during the Cambrian period, a creature lived along the shores of a shallow sea and left tracks that have been found in North America. The fossil tracks are called Climactichnites and while we don’t know what animal actually left them, paleontologists have determined that there were two species and that they were probably slug-like in appearance, possibly an early mollusk, since modern slugs and their relatives sometimes leave similar tracks. We even have some body prints of the stationary animal, and some of them were 27 inches long, or 69 cm.

Similarly, fossilized burrows are considered trace fossils. But often fossilized burrows don’t actually look like holes in the ground. Instead, the burrow has filled up with soil that then fossilizes, leaving the shape of the burrow behind in a rock that looks different from the surrounding rock. And these can be remarkably difficult to identify in some cases.

Back in 1891, a rancher in Nebraska showed a visiting geologist some weird formations he’d found. The geologist, Erwin Barbour, didn’t know what they were. He and the rancher dubbed the formations “devil’s corkscrews,” and probably had a laugh. But the formations did look like corkscrews—but they were enormous, taller than a full-grown man and always situated straight up and down. Some were as long as ten feet, or three meters.

Barbour suggested that the corkscrews were freshwater sponges, since the prevailing belief was that the area had once been a lake. Other scientists thought they might be the remains of fossilized tree or other plant roots. And a couple of people thought they might be fossilized burrows of an unknown rodent.

Those people were right, of course, but at the time, no one knew for sure. And if the corkscrews were burrows, what made them?

The mystery was solved when fossils of a beaver relative called Paleocastor was found at the bottom of one of the corkscrews. Unlike modern beavers, it wasn’t an aquatic rodent but a burrowing one, and it lived around 25 million years ago. Once the Paleocastor fossil was discovered, it was clear that the marks noted on some of the corkscrews, which had been interpreted as scratch marks from claws, were actually tooth marks. They perfectly matched Paleocastor’s teeth, which meant the beaver excavated its corkscrew-shaped burrow by chewing through the dirt instead of digging through it.

So why did Paleocastor dig burrows with such an odd shape? The answer may lie in another fossil found not in the bottom of the burrow but stuck in the corkscrews. Zodiolestes was an extinct weasel relative. Possibly it had gone down the burrow while hunting beavers, become stuck in the tight corkscrew turns in the tunnels, and died.

More recent research shows that Paleocastor burrows were frequently connected to one another with side passages, sometimes hundreds of burrows joined together like the burrows and tunnels of modern prairie dogs. This suggests that Paleocastor was a sociable animal that lived in colonies.

As it happened, Dr. Barbour had been right about one thing. The area where the devil’s corkscrews were initially found had once been a lake. His mistake was not realizing that the structures had been dug into the ground where the lake had once been.

Some of the oldest fossils known are trace fossils called stromatolites. These are stones that were formed by microbes. Early life consisted of microbial mats, colonies of microorganisms like bacteria that grow on surfaces that are either submerged or just tend to stay damp. Microbial mats are still around today, often growing in extreme environments like hot springs and hypersaline lakes. When microbial mats grow on a sea or lake floor, they tend to build upwards, forming columns or even reefs that rise out of the mud and toward the light. But while stromatolites are formed by bacteria, they’re not formed of bacteria. Instead, the stones are formed from grains of sand and other sediments that were trapped and cemented together within the mats, which forms a thin layer of limestone. The layers grow over time, giving stromatolites a banded or striped pattern. But it can be really hard to tell them apart from regular old non-stromatolite rocks that also happen to have a banded pattern. Geologists spend a lot of time studying stromatolites and suspected stromatolites to find out more about them. Microbial mats evolved almost 3.5 billion years ago and it’s possible they were around as much as 4 billion years ago. The earth is about 4.5 billion years old, if you were wondering.

But let’s return to more modern times, with animals and fish and things. Another trace fossil is one I’ve mentioned here a few times, the coprolite. A coprolite is a fossilized poop. Most of the original organic material has been mineralized, preserving it. Coprolites are valuable since paleontologists can cut them open to find out what the animal was eating, if it had intestinal parasites, and lots of other information. Coprolites are also frankly hilarious. Did you know that if you become a scientist whose area of study is coprolites, you’re called a paleoscatologist?

We’ve also talked about gastroliths before. Gastroliths are small stones swallowed by an animal to help digest its food. The stones especially help grind up plant material, which eventually causes the stones to become smooth. Lots of animals use gastroliths for digestion, including birds that eat plants, crocodiles and alligators, seals and sea lions, although they may swallow them by accident, and many dinosaurs, especially sauropods. We know sauropods swallowed stones to help in digestion, because we’ve found gastroliths associated with sauropod fossils.

Other trace fossils include marks an animal may have made during its life, like those tooth marks preserved in the devil’s corkscrews. Skin imprints, or fur or feather imprints, are also trace fossils but are incredibly rare. Sometimes a skin imprint remains in place around an animal’s fossilized body parts, which gives paleontologists incredible insight into what an animal looked like while it was alive. That’s how we know a lot of dinosaurs had feathers. Root cavities are trace fossils too, caused not by animals but by plant roots that burrow into the soil but rot away, leaving a hole that fills with dirt and later fossilizes in the shape of the original roots. There’s even a type of trace fossil called a urolite, which was caused when an animal urinated and the urine stream left marks on soft ground.

Since trace fossils are usually hard to match up with the animal that made them, trace fossils are given scientific names of their own. This allows scientists to refer to them without guessing at what made them, and it reduces confusion.

Trace fossils are remains of biological activity. But animals and plants aren’t the only things that can move soft soil. Cracks in dried-out mud are sometimes fossilized, as are ripple marks from water and little dimples made by raindrops or bubbles. Geologists use these fossilized moments in time to help determine how the rock strata have been shifted by geologic forces. They know that a rock that shows ripple marks was once flat, so if it’s been tipped up sideways or deformed into a curve, they can determine what forces were at work on the rocks over the centuries.

It’s not all that uncommon to find these non-biological traces alongside trace fossils and body fossils. I’ve seen big flat rocks that show the bottom of a shallow sea, with ripple marks, the tracks of tiny animals that trundled around looking for food in the sandy mud, and the occasional fossil like a bryozoan or fragment of shell. It’s the closest thing we have to photographs of prehistoric times.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 102: Three Mystery Apes

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It’s mystery ape time! Learn about de Loys’ ape and two other mystery apes this week!

The only photograph we have of de Loys’ ape:

A white-fronted spider monkey:

Oliver the so-called “ape man”:

A better picture of Oliver late in his life:

A Bili ape:

A regular gorilla (top) and a regular chimp (bottom, hearing no evil) for comparison with the Bili ape and Oliver:

Show transcript:

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

I don’t know about you, but I’m in the mood for a mystery animal this week. So let’s really dig in to a topic I haven’t covered much before, mystery apes!

A lot of people get apes and monkeys confused, but it’s actually easy to tell them apart. For one thing, there aren’t very many apes. Gorillas, chimpanzees, orangutans, and bonobos are called great apes, and gibbons and siamangs are called the lesser apes, mostly because they’re smaller.

Apes never have tails and are closely related to humans. Humans, in fact, are considered great apes, but it’s rude to say so. We like to think we’re special because we can make podcasts and bulldozers and delicious cakes. Monkeys usually have tails, although not always, and a monkey, unlike an ape, can’t stand fully upright and can’t straighten its elbow out so that its arm is flat.

Now that we have a pretty good idea of what an ape is, let’s look at three mystery apes.

We’ll start with a big mystery from 1920, an ape supposedly killed in South America and subsequently dubbed de Loys’ ape. It’s not just one mystery, it’s several mysteries wrapped up together. And while the ape’s body has been lost, we still have a photograph.

In 1917, geologist François de Loys led an expedition to Venezuela and Colombia to search for oil. It was a disaster of an expedition, since not only did they not find oil, almost everyone in the expedition died. According to de Loys, in 1920 what was left of the group was camped along the Tarra River on the border between Colombia and Venezuela when two large animals appeared. De Loys said he thought they were bears at first, then realized they were apes of some kind. They were large, had reddish hair and no tails, and walked upright. The apes became aggressive toward the humans and, fearing for their lives, the geologists shot at the apes. They killed one and wounded the other, which fled.

The dead ape looked like a spider monkey, which was fairly common in the area, but it was much larger and had no tail. There was no way for the expedition to keep the body, so they propped it up on a crate with a stick under its chin to keep it upright, then took pictures. Only one of those pictures survived, since de Loys said the others were lost when a boat capsized later in the expedition.

But after de Loys got home to Europe, he didn’t tell anyone about the ape. He said he forgot all about it until 1929 when the anthropologist George Montandon noticed the surviving photograph in de Loys’s papers. After that, De Loys wrote an article about the ape which was published in the Illustrated London News.

It was a sensational article, not meant to be scientific. Here’s an excerpt:

“The jungle swished open, and a huge, dark, hairy body appeared out of the undergrowth, standing up clumsily, shaking with rage, grunting and roaring and panting as he came out onto us at the edge of the clearing. The sight was terrifying…

“The beast jumped about in a frenzy, shrieking loudly and beating frantically his hairy chest with his own fists; then he wrenched off at one snap a limb of a tree and, wielding it as a man would a bludgeon, murderously made for me. I had to shoot.”

Montandon was enthusiastic about the ape. He wrote three articles for scientific journals and proposed the name Ameranthropoides loysi for it. But scientists were skeptical. Who was this de Loys guy and did he have any proof that the ape wasn’t just a spider monkey? Did he even have proof that the photograph was taken in South America?

Because that’s one of the mysteries. Quite apart from what kind of primate de Loys’ ape might be, if it really is an ape, is it an ape native to South America? There are no apes native to the Americas at all, only monkeys. Chimpanzees, gorillas, and bonobos live in Africa, while orangutans, gibbons, and siamangs live in Asia. If de Loys really did find an ape new to science in South America, it radically changes what we know about ape evolution.

De Loys said he measured the animal as 157 cm high, which works out to about 4.5 feet. This is much larger than a spider monkey, which tops out at about 3.5 feet high, or 110 cm. But we have only de Loys’s word to go by, and as it happens, de Loys was a known practical joker. He also didn’t talk about the ape very often and seems to have only written his article at the urging of Montandon, his friend the anthropologist. We’ll come back to Montandon in a minute.

In 1962, a medical doctor, Enrique Tejera, read an article about de Loys’ ape in a magazine called The Universal. Tejera had worked with de Loys during part of his expedition as a camp doctor, and he had firsthand knowledge about de Loys’ ape. The letter was published, and published again in 1999 in the Venezuelan scientific magazine Interciencia. I’ll read an excerpt of the translated letter:

“This monkey is a myth. I will tell you his story. Mister Montandon said that the monkey had no tail. That is for sure, but he forgot to mention something: it has no tail because it was cut off. I can assure you, gentlemen, because I saw the amputation. In 1917 I was working in a camp for oil exploration in the region of Perijá. The geologist was François de Loys and the engineer Dr. Martín Tovar Lange. De Loys was a prankster and often we laughed at his jokes. One day they gave him a monkey with an infected tail, so it was amputated. After that de Loys called him ‘el hombre mono,’ the monkey man.

“Some time later de Loys and I entered another region of Venezuela, an area called Mene Grande. He always took his monkey along, who died some time later [in 1919]. De Loys decided to take a photo and I believe that Mr. Montandon will not deny it is the same photograph that he presented in 1929.”

The monkey Dr. Tejera said de Loys had been given was a white-fronted spider monkey. And that’s exactly what the photo de Loys took looks like.

I’ll put the photo of de Loys’ ape in the show notes if you want to look at it. There are no people in the photo, nothing except the crate it’s sitting on to use as a size reference. You can’t even see whether the animal has a tail or not.

The white-fronted spider monkey is endangered these days due to habitat loss and hunting, but in the early 20th century it was still common in Colombia, Venezuela, and other parts of northwestern South America. It’s mostly black with a white belly, a long tail, and long arms and legs. That’s why they’re called spider monkeys, incidentally. Long arms and legs like a spider. The white-fronted spider monkey mostly eats fruit, but it also eats leaves, flowers, and other plant parts, and occasionally eats insects. Like many monkeys, its tail is somewhat prehensile and has a bare patch near the end that helps it grip branches like an extra finger. Since the spider monkey doesn’t have actual thumbs on its hands like most primates, it needs that tail to help it get around in trees.

If you look closely at the photograph of de Loys’ ape, you can see that the poor dead monkey does not have thumbs on its hands the way an ape would. It also looks like it has a penis, but that’s actually not a penis. Female spider monkeys have an organ that retains droplets of urine and drips them out as the monkey travels around, leaving a scent trail, and which looks superficially like a penis. It’s actually called a pseudo-penis and it makes it difficult for researchers to determine whether a spider monkey in the wild is male or female at first glance. It’s also an organ only found in spider monkeys and a few other types of monkey, never apes.

So we can be pretty sure de Loys’ ape was actually a spider monkey. But there’s more going on here than a simple hoax. Here’s another excerpt from de Loys’s 1929 article. He writes,

“Until my discovery of the American anthropoid, we could only imagine that man migrated to these shores. But now, in the light of this discovery, it is obvious that the failure of the otherwise well established principle of evolution when it was applied to America was due only to imperfect knowledge. The gap observed in America between monkey and man has been eliminated; the discovery of the Ameranthropoid has filled it.”

What? WHAT? What is that mess of a paragraph trying to say?

Well, basically, it’s promoting Montandon’s theory that humans of different races evolved from different apes. We know these days that that’s nonsense. All humans are genetically the same species, despite superficial physical differences like skin and hair color. Montandon thought that, for instance, people from Africa had evolved from gorillas, Asians evolved from orangutans, while people from Europe—you know, white people—were the only ones actually descended from early Homo sapiens.

In other words, Montandon wasn’t just a terrible scientist, he was a terrible human being, because his theory was pure racism. He was delighted to learn about de Loys’ ape because he decided that was the ape that native Americans must have evolved from. Again, nonsense science, awful person, I’m glad he’s dead. The French Resistance killed him during WWII.

It’s possible that de Loys wasn’t even trying to hoax anyone initially. He just had a pet monkey that died, took a photo as a creepy joke, and stuck the photo in his papers. It was Montandon who came across the photo and urged de Loys to write about it. It’s very likely that Montandon decided to claim the animal was an ape to further his racist theory, and de Loys went along with it, possibly reluctantly given how little he talked about it.

Ugh. Let’s move on to something less infuriating.

Oliver was a strange-looking chimpanzee sometimes referred to as an ape-man back in the 1970s. Oliver had been part of a traveling animal act, but he never fit in with the other chimps in the act and preferred to spend his time with humans, helping with chores. He walked fully upright at all times.

In 1976 an attorney called Michael Miller bought Oliver, mostly because Oliver just looked weird. His head was oddly shaped compared to other chimps and his jaw was smaller and more human-like in appearance. His ears were slightly pointed. The popular press found Oliver interesting and for a short while he was famous, or infamous. Some claims about Oliver were that he had 47 chromosomes instead of a chimp’s normal 48, that he was a mutant, that he was a hybrid between a chimp and some other primate, like a bonobo, or even an ape-man somewhere between a human and a chimp.

Oliver had a rough life, honestly. Michael Miller sold him to a theme park in 1977, and after that Oliver was passed from theme park to theme park. Interest in Oliver died down after a while, and in 1989, he was bought by a laboratory that leased out animals for testing. Oliver was never used as an experimental animal, but he lived for seven years in a cage so small he could barely move, so that his muscles atrophied.

Fortunately, in 1996 Oliver finally got a break and moved to an animal sanctuary in Texas. He had a spacious territory of his own, a chimp mate called Raisin, and lived out the rest of his days in peace. He died in 2012 at the age of about 55.

When the sanctuary acquired Oliver, they had him genetically tested to see if he really was a hybrid animal. It turned out that Oliver’s chromosome count was normal for a chimpanzee, and that he was genetically dead normal in every respect. So why did he look so weird?

Mainly, it was because his teeth had all been pulled at an early age so he couldn’t bite. This barbaric practice resulted in his jaw muscles being underdeveloped and his jaw bones becoming shortened. His head and ear shape were well within normal range for chimps, but only looked strange when combined with his poorly developed jaw. And the reason he walked upright all the time was because he’d been trained to do so.

After Oliver died, the sanctuary cremated his body and spread his ashes on the grounds where he had lived peacefully for the first time in his life.

Our last mystery ape this week is called the Bili ape. In 1898, a Belgian army officer donated some skulls to a museum in Belgium, skulls which he said were from gorillas killed in what is now the Democratic Republic of Congo. Specifically, he said the gorillas lived in a forest near the village of Bili in an area referred to as Bondo. So after a museum curator examined the skulls and realized they weren’t the same as other gorilla skulls and not from an area where gorillas were known to live, the mystery ape was dubbed the Bili ape or the Bondo ape. The curator thought the Bili ape was a subspecies of gorilla.

In 1970 a mammalogist examined the skulls and determined that they were just regular old western lowland gorilla skulls. Nothing exciting. But a conservationist and photographer named Karl Ammann wasn’t convinced. He decided to go out and see if he could find the Bili ape for himself, take pictures, and see what the ape really was. In 1996, he took his cameras and went looking for gorillas.

He didn’t find any, but he did find a skull. It looked sort of like a gorilla skull, which has what’s called a sagittal crest that runs along the top of the skull and which allows the attachment of a gorilla’s powerful jaw muscles. But the rest of the skull looked more like a chimpanzee’s. Ammann also bought a photograph taken from a poacher’s trail cam that showed what looked like huge chimps. He also found great big poops and great big footprints, larger even than a gorilla’s footprint.

He had enough evidence to interest researchers, so in 2001 he and a team of scientists returned to find the Bili ape. They had no luck, partly because there was a civil war going on in the area at the time and getting around without getting killed was difficult. But they did find evidence that the apes were there, and the evidence was confusing. Gorillas build nests on the ground to sleep in, and the team did find big nests on the ground. But gorillas don’t like swampy ground and they move around a lot and build a new nest every night. These nests were often in swampy areas and showed evidence that they were reused. Chimps prefer to sleep in trees. But while the feces the researchers collected from around the nests were big enough to be gorilla poops, they indicated the apes’ diet was high in fruit, which is typical of chimps.

The team returned to the area in 2003 after the civil war ended, and this time they found the Bili ape.

The first scientist to see a Bili ape was a primate behavior specialist named Shelly Williams. The whole group heard the apes in the trees around them, very close to them, and then four apes rushed at the group. Williams knew they weren’t trying to intimidate the humans, they were going to kill them—I mean, that’s what it means to be a primate behavior specialist. It apparently means you know when you’re about to die at the hands of an enraged mystery ape. But the apes caught sight of her, stopped short, and returned into the brush.

If that happened to me, for one thing I would wet myself, and for another I would wonder for the rest of my life if I was an extra pretty human, or if I was extra pretty for a chimp or gorilla. But as it happens, Williams knew that the apes weren’t after the humans specifically but had responded to a call made by the team’s tracker, who had imitated the noise a wounded antelope makes. Imagine the scene from the apes’ point of view. You’re out hunting with your buddies, you hear some loud noises of animals walking through the forest. Then you hear an antelope. You and your buddies rush out, already thinking about how good that antelope is going to taste—and instead of antelopes, you see a bunch of humans. Of course you’re going to beat feet, because those humans might be hunting you.

Williams was the only scientist in the group to get a look at the apes that day, and they confused her. They mostly looked like chimps, but they were huge. A male common chimpanzee is about five feet tall when standing, or 1.5 meters, with females usually about a foot shorter, or 30 cm shorter. The Bili ape was way bigger, closer to six feet tall, or 1.8 meters. This is the height of a gorilla. Williams wasn’t sure if she’d seen giant chimps or weird gorillas or something else entirely.

After that first sighting, the team was able to get video and photos of the Bili apes. They resemble large chimps with gorilla-like heads, and Williams thinks the females and young mostly sleep in trees, while adult males sleep on the ground. They seem to live and travel in small groups, compared to chimps that usually live in troupes of up to 50 members.

The locals in the area say there are two different kinds of Bili ape. The smaller ones prefer to live in trees and are known as tree-beaters. The larger ones live on the ground and are called lion-killers. The lion-killers are supposed to be immune to the poison-dart frog secretions that locals use to poison their arrow tips.

DNA samples from dung and hair finally cleared up the mystery. Results indicate that the apes are chimpanzees, specifically a known subspecies of the common chimpanzee. Researchers think the Bili ape may look and act different since it’s so isolated from other chimps and may be somewhat inbred. Bili apes encountered far from villages show very little fear or aggression toward humans, only curiosity. Unfortunately, the chimps are under increased threat from poaching, since gold mining began in the area in 2007 and the population of humans has increased. Hopefully protections can be put into place soon so these rare chimpanzees can remain safely in their homes and can continue to be studied by researchers.

One exciting thing to remember is that the area where the Bili ape lives is still quite remote. There could very well be other animals unknown to science hidden in the forests. That’s yet another reason to protect the forest and everything that lives in it. You never know what might be out there ready to be discovered.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 101: Flying Without Wings

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What better way to start out the new year than by learning about some animals that fly (or glide) without wings! Thanks to Llewelly for suggesting the colugo!

Colugo looking startled:

A colugo, flying, which startles everyone else:

Flying fish! ZOOM!

A flying gurnard, not flying:

Flying squid! ZOOM!

Flying squid close-up, mid-zoom:

Show transcript:

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

It’s the first week of a new year, so let’s start it off right and learn about some animals that fly without wings.

The first of our non-winged flying animals is a suggestion from Llewelly, who sent me some links about it and we both freaked out a little because it’s such an awesome animal. It’s called the colugo, and technically it doesn’t fly, it glides. It looks kind of like a big squirrel and kind of like a small lemur, and in fact it’s also sometimes called a flying lemur. But it’s not closely related to squirrels or lemurs. It’s actually not related closely to anything alive today.

Before we learn about the colugo specifically, let me explain a little bit about gliding animals. Gliding animals have a flap of skin called a gliding membrane or patagium. In the case of gliding mammals, like the flying squirrel or the colugo, the patagium connects each foreleg with the hindleg on that side. When the animal wants to glide, it stretches its legs out, which also stretches out the patagium. For a long time scientists assumed that the patagium was just skin and didn’t do anything except increase the animal’s surface area and act as a sort of parachute. But it turns out that the patagium contains tiny muscles like those recently discovered in the membranes of bat wings. And the skin between the fingers of the bat’s forelimbs, which creates the wings, are actually considered patagia. In fact, any gliding membrane, even if it’s part of a real wing, is considered a patagium, so birds actually have them too.

The colugo has a patagium between its legs like other gliding mammals, but it also has a patagium between its hind legs and its tail, and even its fingers and toes are connected with small patagia. It’s the most well-adapted mammal known for gliding, so well-adapted that it can glide incredible distances. One was measured as having glided almost 500 feet in one jump, or 150 meters. This is almost the length of two football fields.

The colugo lives in South Asia and is endangered mainly due to habitat loss. It grows to about 16 inches long, or 40 cm, with a small head, big eyes, and little round ears. It’s gray with some mottled white and black markings that help hide it against tree trunks, and its legs are long and slender. It eats plants. We don’t know a whole lot about the colugo, because it’s shy and lives in the treetops of tropical forests, but what we do know is really weird.

For instance, its babies. If you listened to episode 45 about monotremes, where we also discuss the differences between marsupial and placental mammals, you may remember that placental mammal babies are born mostly developed while marsupial mammal babies are born very early and finish developing outside of the mother, either in a pouch or just clinging to the mother’s fur. Well, the colugo is a placental mammal, but its babies are born extremely early, more like a marsupial. They finish developing outside of the mother, which takes six months or so, and the mother colugo keeps her tail curved up most of the time so that her patagium is wrapped around her babies like a pouch.

The colugo has weird teeth, too. The front teeth, or incisors, are shaped like tiny combs. This is similar to the incisors of lemurs, which look like tiny combs because the lemur uses them as tiny combs to groom its fur. But unlike any other mammal known, some of the colugo’s upper incisors have two roots instead of just one. Why? No one knows.

So what is the colugo related to? For a long time, no one was sure. Researchers even thought it might be a close relation of bats. These days, the two species of colugo make up their own order, Dermoptera. Order is the classification right below mammal so that’s kind of a big deal. While they’re not closely related to anything alive today, researchers place them in the same general group of animals that gave rise to the primates. But they’re about as closely related to rabbits as they are to monkeys.

In 2017 a team of scientists surveying bats in Malaysia picked up a recording of some unusual ultrasonic calls. They weren’t bat calls. Eventually they determined the calls came from colugos in the trees around the microphones, although some researchers have doubts and think the calls may actually be from other animals known to make ultrasonic sounds, like the tarsier. The colugo has been recorded making sounds audible to humans in other studies. There’s no evidence that the colugo uses echolocation like bats do.

Mammals took to gliding very early on. A few years ago, two fossils discovered in China and dated to about 160 million years ago—you know, 100 million years before the dinosaurs died out—show two different species of mammal that were able to glide. We know they could glide because the fossils are so well preserved that researchers can see the patagium between the front and hind legs of both. They’re the earliest known gliding mammals. Both the fossils belonged to a branch of mammals that have completely died out, so they’re not related to the colugo or anything else.

So what other animals fly, or glide, without real wings? You’ve heard of flying fish, of course. Do they really jump out of the water and glide on their fins? They do, and it’s a lot more awesome even than it sounds.

There isn’t just one species of flying fish but over 60, all of them with elongated pectoral fins that act like an airplane’s wings when they jump out of the water. Some species have two pairs of elongated fins. Back in the early 20th century, engineers studied flying fish fins to help design better airplane wings. But the flying fish has a lot of other adaptations that make it good at gliding, including a stiffened body and robust spine, and strong muscles that allow it to jump out of the water at high speeds.

So how well does the flying fish glide? This is where it gets crazy amazing. The longest recorded flight of a flying fish was 1,300 feet, or 400 meters. That’s way better than the colugo. It’s been recorded as reaching 20 feet, or 6 meters, above the water’s surface and flying at speeds of about 45 mph, or 70 km/h. And as if this wasn’t amazing enough, when the fish starts to descend, it can choose to slide back into the water or it can put its tail down and push off against the surface of the water to get back in the air for another glide. It can even change directions when it pushes back off. It will sometimes flap its fins like wings, but so far researchers haven’t found any evidence that this helps it fly. It may just flap its fins to stabilize its flight.

Most flying fish species are fairly small, although the biggest is a respectable 1 1/2 feet long, or about half a meter. Most flying fish live in the ocean, usually in warmer waters, and they’re all extremely slender and streamlined. They mostly eat plankton.

Sometimes flying fish land in boats or even on the decks of small ships. It’s considered a delicacy, with a taste similar to that of a sardine, and many species have started to decline as a result of overfishing.

Gliding flight has evolved in fish more than once in species that aren’t related, so there are more flying fish than there are flying fish, if you see what I mean. No, you don’t. That only made sense to me. The earliest known flying fish is a fossil dated some 240 million  years old, totally unrelated to the flying fish of today. And there are species alive today not related to the various flying fish species that can glide, if not as well as actual flying fish.

One fish that may or may not glide is called the flying gurnard. It’s a bulky fish that grows more than a foot and a half long, or 50 cm, and can weigh four lbs, or 1.8 kg. It lives in the warmer parts of the Atlantic Ocean in shallow coastal areas, where it mostly stays on the seafloor and eats crustaceans, bivalves, and other small invertebrates. It will also eat small fish if it can catch them. It has a face sort of like a frog’s and can be reddish, brown, or greenish, with spots and patches of other colors. But most importantly, its pectoral fins are extremely large, looking more like fan-like wings than fins. The so-called wings are shimmery, semi-transparent, and lined with bright blue. They sort of look like butterfly wings and can be more than 8 inches long, or 20 cm. The fins actually have two parts, a smaller section in front that looks more like an ordinary fin, and the larger wing-like section behind.

The flying gurnard’s popular name refers to its wing-like fins, which it uses to scare potential predators and to walk around on the sea floor with and poke into the sand to find food. But there are stories dating back thousands of years that not only can the flying gurnard jump out of the water to fly, its flight resembles a swallow’s swooping flight. But it’s much too heavy to fly, so those stories are only tall tales. OR ARE THEY? At least one ichthyologist, a Dr. Humphrey Greenwood, reports having seen a flying gurnard leap out of the water, spread its fins, and glide in a controlled manner for a short distance.

The last animal that flies, or glides, without wings is one I bet you would never guess. It’s the flying squid. And yes, I thought it was a made-up animal when I first heard about it. Squid can’t fly! But there one squid that does regularly leap out of the water and glide for short distances.

The Japanese flying squid lives near the ocean’s surface in schools, where it eats fish and crustaceans. Despite its name, it doesn’t just live around Japan but throughout much of the Pacific Ocean. It doesn’t live very long, less than a year, but has a complicated migratory life. Not as complicated as an eel, but pretty complicated. A squid hatches only five days or so after its mother lays the eggs. The baby squid, called a paralarva, eats plankton and doesn’t yet have arms or tentacles, since they’re fused together at first. The fused tentacles split once the baby has grown to about half an inch long, or some 10 mm, which gives you an idea of how tiny it is when it first hatches.

As the baby squid grows, it begins its migration with the other baby squids that hatched at the same time. The migration follows the ocean surface currents and different subspecies have different migration patterns. Males mature first and transfer their packets of sperm, called spermatophores, to the females for later. Then the males die and the females continue their migration back to the same area where they were hatched. They lay a few hundred to a few thousand tiny eggs and then die, leaving the eggs to hatch only a few days later and start the whole process again.

I can hear you thinking, Why yes, Kate, this is all very interesting BUT YOU HAVE NOT TOLD US HOW SQUIDS FLY. Okay, I’ll do that now.

The Japanese flying squid has a mantle, or main part of the body and head, with a pair of fins at the end that stick out quite a bit. Its eight legs and two feeding tentacles are relatively short, shorter than its mantle length of about a foot and a half long in a big female, or 50 cm. Males are smaller. Like all squids and octopuses, the flying squid moves by shooting water out of its siphon, making it jet-propelled. It travels mantle first with the legs trailing behind.

Well, the Japanese flying squid jumps out of the water and shoots through the air this way, with the fins on its mantle helping to stabilize the squid when it’s in the air and keep it flying straight. It also holds its legs and tentacles out so that the membrane between the legs is stretched taut, making a flat surface that it can angle to catch the most air. It can “fly” some 150 feet, or 50 meters, per jump, traveling at about 25 mph, or 11 meters per second. Researchers used to think it only jumped out of the water to avoid predators, but more recent studies show that it’s also a more efficient way to travel long distances than just staying in the water. Oh, and no one knew for sure that the Japanese flying squid could actually fly until about 15 years ago when researchers caught video of it happening.

Like other squids, the Japanese flying squid can change colors and release a cloud of ink to confuse predators. It also has three hearts.

There are other gliding animals and they’re all weird and interesting, so I’ll probably revisit this topic again in the future. In the meantime, if you want to learn about flying snakes, you can go back and listen to episode 56 about strange snakes. Since that’s currently my 8th most popular episode, you may have listened to it already. Thanks.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 100: The Centipede of Episodes!

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It’s our 100th episode! Thanks to my fellow animal podcasters who sent 100th episode congratulations! Thanks also to Simon and Julia, who suggested a couple of animals I used in this episode.

An Amazonian giant centipede eating a mouse oh dear god no:

The kouprey:

The Karthala scops owl:

A sea mouse. It sounds cuter than it is. Why are you touching it? Stop touching it:

A sea mouse in the water where it belongs:

Mother and baby mountain goats. Much cuter than a sea mouse:

A hairy octopus:

Further reading:

Silas Claiborne Turnbo’s giant centipede account collection

Show transcript:

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

This is our 100th episode! I’ll be playing clips from some of my favorite animal podcasts throughout the show, and I highly recommend all of them if you don’t already listen!

For our big 100 show, I’ve decided to cover several animals, some mysterious, some not so mysterious, and all weird. But we’ll start with one that just seems to fit with the 100th episode, the centipede—because centipedes are supposed to have 100 legs.

So do they have 100 legs? They don’t, actually. Different species of centipede have different numbers of legs, from only 30 to something like 300. Centipedes have been around for some 430 million years and there are thousands of species alive today.

A centipede has a flattened head with a pair of long mandibles and antennae. The body is also flattened and made up of segments, a different number of segments depending on the centipede’s species, but at least 15. Each segment has a pair of legs except for the last two segments, which have no legs. The first segment’s legs project forward and end in sharp claws with venom glands. These legs are called forcipules, and they actually look like pincers. No other animal has forcipules, only centipedes. The centipede uses its forcipules to capture and hold prey. The last pair of legs points backwards and sometimes look like tail stingers, but they’re just modified legs that act as sensory antennae. Each pair of legs is a little longer than the pair in front of it, which helps keep the legs from bumping into each other when the centipede walks.

Like other arthropods, the centipede has to molt its exoskeleton to grow larger. When it does, some species grow more segments and legs. Others hatch with all the segments and legs they’ll ever have.

The centipede lives throughout the world, even in the Arctic and in deserts, which is odd because the centipede’s exoskeleton doesn’t have the wax-like coating that other insects and arachnids have. As a result, it needs a moist environment so it won’t lose too much moisture from its body and die. It likes rotten wood, leaf litter, soil, especially soil under stones, and basements. Some centipedes have no eyes at all, many have eyes that can only sense light and dark, and some have relatively sophisticated compound eyes. Most centipedes are nocturnal.

Many centipedes are venomous and their bites can cause allergic reactions in people who also react to bee stings. Usually, though, a centipede bite is painful but not dangerous. Small centipedes can’t bite hard enough to break the skin. I’m using bite in a metaphorical way, of course, since scorpions “bite” using their forcipules, which as you’ll remember are actually modified legs.

The largest centipedes alive today belong to the genus Scolopendra. This genus includes the Amazonian giant centipede, which can grow over a foot long, or 30 cm. It’s reddish or black with yellow bands on the legs, and lives in parts of South America and the Caribbean. It eats insects, spiders, including tarantulas, frogs and other amphibians, small snakes, birds, mice and other small mammals, and lizards. It’s even been known to catch bats in midair by hanging down from cave ceilings and grabbing the bat as it flies by. Because it’s so big, its venom can be dangerous to children. A four-year-old in Venezuela died in 2014 after being bitten by one, but this is unusual, and bites generally only lead to a few days of pain, fever, and swelling.

You’ll often hear that the Amazonian giant centipede is the longest in the world, but this isn’t actually the case. Its close relation, the Galapagos centipede, is substantially longer. The Galapagos Islands have EVERYTHING. The Galapagos centipede can grow 17 inches long, or 43 cm, and is black with red legs.

Another member of Scolopendra is the waterfall centipede, which grows a mere 8 inches long, or 20 cm, but which is amphibious. The waterfall centipede was only discovered in 2000, when entomologist George Beccaloni was on his honeymoon in Thailand. Naturally he was poking around looking for bugs, and I trust his spouse was aware that that’s what he would do on his honeymoon, when he spotted a dark greenish-black centipede with long legs. It ran into the water and hid under a rock, which he knew was extremely odd behavior for a centipede. They need moisture but they avoid entering water. Beccaloni noted that the centipede was able to swim in an eel-like manner. He captured it and later determined it was a new species. Only four specimens have been found so far in various parts of South Asia. Beccaloni hypothesizes that it eats insects and other small animals found in the water.

There are stories of huge centipedes found in the depths of jungles throughout the world, centipedes longer than a grown man is tall. These are most likely tall tales, since centipedes breathe through tiny notches in their exoskeleton like other arthropods and don’t have proper lungs. As we learned in the spiders episode a few months ago, arthropods just can’t get too big or they can’t get enough oxygen to live. But some of the stories of huge unknown centipedes have an unsettling ring of truth.

There are stories from the Ozark Mountains in North America about centipedes that grow as long as 18 inches, or almost 46 cm. Historian Silas Claiborne Turnbo collected accounts of giant centipede encounters in the 19th century, which are available online. I’ll put a link in the show notes.

All the accounts come across as truthful and not exaggerated at all. I think it’s worth it to read the last few paragraphs of the centipedes chapter of Turnbo’s manuscript verbatim, because they’re really interesting and I kept finding garbled accounts of the stories in various places online. Whenever possible, go to the primary source.

“R. M. Jones, of near Protem, Mo., tells of finding a centipede once imprisoned in a hollow tree. Mr. Jones said that after his father, John Jones, settled on the flat of land on the east side of Big Buck Creek in the southeast part of Taney County, his father told him one day in the autumn of 1861 to split some rails to build a hog pen. Going out across the Pond Hollow onto the flat of land he felled a post oak tree one and one-half feet in diameter. There was a small cavity at the butt of the tree. After chopping off one rail cut he found that the hollow extended only four or five feet into the rail cut, and was perfectly sound above it. After splitting the log open he was astonished at finding a centipede eight inches in length, coiled in a knot in the upper part of the cavity. At first there appeared to be no life about it. ‘I took two sticks,’ said he, ‘and unrolled it and found that it was alive. It was wrapped around numerous young centipedes which were massed together in the shape of a little ball. The old centipede was almost white in color. After a thorough examination of the stump and the ground around it, I found no place where the centipede could have crawled in. Neither, in the log, was there any place where it could enter. How it got there I am not able to explain and how long it had been an inhabitant there is another mystery to me.’

“William Patton, who settled on Clear Creek in Marion County, Ark., in 1854 and became totally blind and is dead now, says that one day while his eyesight was good he was in the woods on foot stock hunting. When about 1 ½ miles west of where the village of Powell now is, he noticed something a short distance from him crawl into a hollow tree at the ground. ‘On approaching the tree to identify the object,’ remarked Mr. Patton, ‘I saw a monster centipede lying just on the inside of the hollow which was the object I had just observed crawl into the tree. I placed the muzzle of my rifle near the opening and shot it nearly in twain, and taking a long stick I pulled it out of the hollow and finished killing it with stones. I had no way of measuring it accurately, but a close estimation proved that it was not less than 14 inches long and over an inch wide.’

“The biggest centipede found in the Ozarks that I have a record of was captured alive by Bent Music on Jimmies Creek in Marion County in 1860. Henry Onstott an uncle of the writer and Harvey Laughlin who was a cousin of mine kept a drugstore in Yellville and collected rare specimens of lizards, serpents, spiders, horned frogs and centipedes and kept them in a large glass jar which sat on their counter. The jar was full of alcohol, and the collection was put in the jar for preservation as they were brought in. Amongst the collection was the monster centipede mentioned above. It was of such unusual size that it made on almost shudder to look at it. Brice Milum, who was a merchant at Yellville when Mr. Music brought the centipede to town, says that he assisted in the measuring of it, before it was put in the alcohol and its length was found to be 18 inches. It attracted a great deal of attention and was the largest centipede the writer ever saw. The jar with its contents was either destroyed or carried off during the heat of the war. Henry Onstott died in Yellville and is buried in the old cemetery one half a mile west of town.”

There are large centipedes around the Ozarks, including the red-headed centipede that can grow over eight inches long, or 20 cm. A hiker was bitten by a six-inch red-headed centipede a few years ago in Southwestern Missouri and had to be treated at a hospital. The red-headed centipede mostly stays underground during the day, although it will come out on cloudy days. It has especially potent venom and lives in the southwestern United States and northern Mexico. And, interestingly, females guard their babies carefully for a few days after they hatch. Since the red-headed centipede is a member of the genus Scolopendra, the ones that grow so long, I wouldn’t be a bit surprised if individuals sometimes grow much longer than eight inches.

One story of a giant centipede called the upah turned out to have a much different solution. Naturalist Jeremy Holden was visiting a village in western Sumatra in the early 2000s when he heard stories of the upah. It was supposed to be a green centipede that grew up to about a foot long, or 30 cm, and had a painful bite. It was also supposed to make an eerie yowling sound like a cat. Holden discounted this as ridiculous, since no centipedes are known to make vocalizations of any kind, until he actually heard one. He was in the forest with a guide, who insisted that this was the upah. The sound came from high up in the treetops so Holden couldn’t see what was making it. But on a later trip to Sumatra with a birdwatcher friend, Holden heard the same sound, but this time the friend knew exactly what was making it. It wasn’t a centipede at all but a small bird called the Malaysian honeyguide. The honeyguide has a distinctive catlike call followed by a rattling sound, but is extremely hard to spot even for seasoned birdwatchers with powerful binoculars. This is what a Malaysian honeyguide sounds like, if you’re curious:

[honeyguide call]

The worst kind of centipede is the house centipedes. I hate those things. I’d rather have a pet spider that lives in my hair than touch a house centipede. House centipedes are the really fast ones that have really long legs that sort of make them look like evil feathers running around on the walls.

Next, let’s take a look at the kouprey, a bovine that is rare and possibly extinct. Thanks to Simon who suggested this ages ago, after the mystery cattle episode, or at least he mentioned it to me while we were talking on Twitter.

The kouprey is a wild ox from Southeast Asia and may be closely related to the aurochs. It’s big and can stand over six feet tall at the shoulder, or almost two meters. It has long legs, a slightly humped back, and a long tail. Males have horns that look like typical cow horns, but females have horns that spiral upward like antelope horns. Cows and calves are gray with darker bellies and legs, while grown bulls are dark brown with white stockings. It lives in small bands led by a female and eats grass and other plants. Males are usually solitary or may band together in bachelor groups. It likes open forest and low, forested hills. Sometimes it grazes with herds of buffalo and other types of wild ox.

The kouprey wasn’t known to science until 1937, when a bull was sent to a zoo in Paris from Cambodia. It was already rare then. A 2006 study that showed the kouprey was actually a hybrid of a domestic cow and another species of wild ox, the banteng, was later rescinded by the researchers as inaccurate. Genetic studies have since proven that the hybrid hypothesis was indeed wrong.

Unfortunately, if the kouprey still exists, there are almost none left. In the late 1960s only about 100 were estimated to still remain. While it’s protected, it’s poached for meat and horns, and is vulnerable to diseases of domestic cattle and habitat loss. The last verified sighting of a kouprey was in 1983, and there are no individuals in captivity. But conservationists haven’t given up yet. They continue to search for the kouprey in its historical range, including setting camera traps. Since the kouprey looks very similar to other wild oxen, it’s possible there are still some hiding in plain sight.

Next up, let’s look at a rare owl. Thanks to Julia who suggested the Karthala scops owl, which only lives in one place in the world. That one place in the world happens to be an active volcano. Specifically, it lives on the island of Grande Comore between Africa and Madagascar, in the forest on the slopes of Mount Karthala.

It’s a small owl with a wingspan of only 18 inches, or 45 cm. Some of the owls are greyish-brown and some are dark brown. It probably eats insects and small animals, but not much is known about it. It’s critically endangered due to habitat loss, as more and more of its forest is being cut down to make way for farmland. It sounds like this, and if you don’t think this is adorable I just can’t help you:

[owl call]

The Karthala scops owl wasn’t discovered by science until 1958, when an ornithologist named C.W. Benson found a feather living a sunbird nest. He thought it might be a nightjar feather, but it turned out to belong to an unknown owl. At first researchers thought it was a subspecies of the Madagascar scops owl, but it’s now considered to be a new species. Unlike many other scops owl species, the Karthala scops owl doesn’t have ear tufts.

That’s pretty much all that’s known about the Karthala scops owl right now. Researchers estimate there are around 1,000 pairs living on the volcano, and hopefully conservation efforts can be put into place to protect their habitat.

The sea mouse has been on my ideas list from the beginning, so let’s learn a little bit about it today too. It’s not a mouse, although it does live in the sea. It’s actually a genus of polychaete worm that lives along the coasts of the Mediterranean Sea and the Atlantic Ocean, although it doesn’t really look like a worm. It looks kind of mouse-like, if you’re being generous, mostly because it has setae, or hairlike structures, on its back that look sort of like fur. Some species grow up to a foot long, or 30 cm, but most are usually smaller, maybe half that size or less. It’s shaped roughly like a mouse with no head or tail, and is about three inches wide, or 7.5 cm, at its widest.

The sea mouse is usually a scavenger, although at least one species hunts crabs and other polychaete worms. It spends a lot of its time burrowing in the sand or mud on the ocean bed, looking for decaying animal bodies to eat. It also has gills and antennae, although these aren’t readily noticeable because of the setae covering the animal’s back.

Underneath the setae, the sea mouse is segmented. It doesn’t have real legs but it does have appendages along its sides called parapodia, which it uses like little leglets to push itself along. Sometimes a sea mouse is found washed ashore after a storm. Often it scurries through the wet sand and looks even more like a mouse.

The most interesting thing about the sea mouse is its setae. The setae are about an inch long and are dark red, yellow, black, or brown under ordinary circumstances, depending on species. But when light shines on them just right, they glow with green and blue iridescence. The setae are hollow and made of chitin. The setae are much thinner than a human hair, and nanotech researchers have used them to create nanowires.

Here’s a sweet little mystery animal I got from one of my favorite books, Karl Shuker’s Search for the Last Undiscovered Animals. In 1858, French missionary Emmanuel Domenech published a book called Missionary adventures in Texas and Mexico. A personal narrative of six years’ sojourn in those regions, and in that book he mentions an interesting animal. This event apparently took place in or near Fredericksburg, Texas, sometime before about 1850. The woman in question may have been Comanche. I’ll quote the relevant passage, from pages 122 and 123 of the book.

“An American officer assured me that he had seen an Indian woman, dressed in the skin of a lion which she had killed with her own hand—a circumstance which manifested on her part no less strength than courage, for the lion of Texas, which has no mane, is a very large and formidable animal. This woman was always accompanied by a very singular animal about the size of a cat, but of the form and appearance of a goat. Its horns were rose-coloured, its fur was of the finest quality, glossy like silk and white as snow; but instead of hoofs this little animal had claws. This officer offered five hundred francs for it; and the commandant’s wife, who also spoke of this animal, offered a brilliant of great value in exchange for it; but the Indian woman refused both these offers, and kept her animal, saying that she knew a wood where they were found in abundance; and promised, that if she ever returned again, she would catch others expressly for them.”

So what could this strange little animal be? It sounds like a mountain goat. Mountain goats live in mountainous areas of western North America, but might well have been unknown elsewhere in the mid-19th century. They’re pure white with narrow black horns and hooves, but an albino individual might have horns that appear to be pinkish, at least at the base where the horn core is, due to lack of pigment in the horns allowing blood to show through the surface. While male mountain goats can grow more than three feet tall at the shoulder, or 1 meter, females are much smaller and have smaller horns. Most tellingly, mountain goats have sharp dewclaws as well as cloven hooves that can spread apart to provide better traction on rocks. To someone not familiar with mountain goats, this could look like claws rather than feet. My guess is the woman had a young mountain goat she was keeping as a pet, possibly an albino one, which would explain its size and appearance. It’s nice to think that she cared so much for her little pet that she refused huge amounts of money for it.

Let’s finish up with a rare and tiny cephalopod called the hairy octopus. It’s tiny, only two inches across, or five centimeters, and covered with strands of tissue that give it its name. The so-called hair of the hairy octopus camouflages it by making it look like a piece of seaweed or algae. It can also change colors like other octopuses, to blend in even more with its surroundings. It can appear red, brown, cream, or white, with or without spots and other patterns. It’s only ever been seen in the Lembeh Strait off the coast of Indonesia, and then only rarely.

It’s so rare, in fact, that it still hasn’t been formally described by science. So if you’re thinking about becoming a biologist and you find cephalopods like octopus and squid interesting, this might be the field for you. You might get to give the hairy octopus its official scientific name one day!

Thanks so much to all of you, whether you’re a fellow podcaster, a Patreon subscriber, a regular listener, or someone who just downloaded your first episode of Strange Animals Podcast to see if you like it. I’m having a lot of fun making these episodes, and I’m always surprised at how many people tell me they enjoy listening. I tend to forget anyone listens at all, so whenever I get an email or a review or someone tweets to me about an episode, I’m always startled and pleased. I’ve been trying hard to make the show’s sound quality better, and while I don’t always have the time to do as much research for each episode as I’d like, I do my best to make sure all the information I present is up to date and as accurate as possible.

As always, you can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening, and happy new year!