Episode 104: Tiger Salamanders

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:


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

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:


A “devil’s corkscrew”:

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



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

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

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!