Episode 114: The Depths of the Sea of Cortez

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The Gulf of California, AKA the Sea of Cortez, is home to thousands upon thousands of animals, many of them not found anywhere else in the world. New research expeditions in its deep-sea fissures and trenches have turned up some amazing new animals too. Let’s take a look at a few of them!

Thanks to Hally for this week’s topic suggestion!

The lollipop catshark sounds cuter than it is:

The black brotula:

A super creepy grenadier fish. Look at those EYES:

A type of batfish. It uses its stiff fins to walk around on the bottom of the ocean:

Some beautiful hydrothermal chimneys:

Giant tube worms:

Show transcript:

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

It’s been a while since we did a deep-sea episode. This week let’s find out about some strange fish discovered in the Pacific Ocean off the coast of Mexico. Thanks to Hally for the suggestion!

The Gulf of California, also called the Sea of Cortez, is the stretch of water between mainland Mexico and the Baja peninsula. Researchers estimate it started forming over 5 million years ago when tectonic forces separated the strip of land now called Baja peninsula or Baja California from the mainland. It’s still attached to the mainland at its northern edge, where the Colorado River empties into the gulf. The sea is about 700 miles wide, or over 1100 km.

Because the gulf was formed by tectonic forces and undersea volcanos, parts of it are extremely deep—more than 12,500 feet deep in places, or 3,800 meters. It’s full of islands, nearly 1,000 of them, a few of them quite large and some just tiny, some of them volcanic and some not. And it’s rich in ocean life, with many animals found in the Gulf of California that live nowhere else in the world.

For instance, the lollipop catshark! What a cute name. It probably plays ukulele and its best friend plays the xylophone. They should start a band!

The lollipop catshark is actually not super cute, although it is pretty awesome. It’s a small shark, only about 11 inches long, or 28 cm, and it has pinkish gray skin that’s almost gelatinous in texture, although it also has tiny spiky denticles, especially on its back. It gets the name lollipop from its shape. It has a broad head with large gills, but its body tapers to a slender tail so that it’s sort of shaped like a tadpole. Not really lollipop shaped, frankly. Babies are born live instead of hatching from eggs, with a female giving birth to two babies at a time. It eats crustaceans and fish.

The reason the lollipop catshark has such big gills is that it lives at the bottom of the ocean where there’s not much oxygen. The Gulf of California is especially oxygen-poor in its deepest areas, so when a team of scientists sent a submersible to the deepest parts of the gulf in 2015, they didn’t expect to find that many fish or other animals. But not only were there a lot of lollipop catsharks, there were lots of other animals too.

The submersible found the most fish in a part of the gulf called the Carralvo Trough, which is nearly 3,300 feet deep, or 1,000 meters. A few years before, a submersible had discovered the bodies of dozens of dead squid in the trough, and researchers determined that the squid were all females that had laid eggs and then died and sunk to the bottom. The dead squid are usually eaten by scavengers within 24 hours of dying, including crabs and sea stars, brittle stars, and acorn worms, as well as small bottom-dwelling sharks like the lollipop catshark. So it was good timing that the submersible saw so many of them at once.

Another deep-sea animal found in the Gulf of California is the cusk eel. There are lots of species of cusk eel that live throughout the world’s oceans and even some fresh water, and despite the name, cusk eels are fish, not eels. They’re related to cod, although not closely. They live on the bottom of the ocean, usually in shallow water, where they burrow in the sediment and sand at the bottom.

But the cusk eel found in the Carralvo Trough is called the black brotula, and it’s so different from other cusk eels that it has its own genus. The black brotula grows up to 10 inches long, or about 25 cm, and only lives in the depths of the Gulf of California and in some deep areas along the western coast of Mexico and Chile. Not only can it tolerate low-oxygen water, it prefers it. It’s black or dark gray in color–even its intestines are black. And that’s pretty much all we know about it at this point. Cusk eels are generally not very well studied, and the black brotula is hard to study because it lives so deep in the gulf. Researchers don’t even know how it tolerates water with so little oxygen and what it eats down there. We do know that young black brotulas prefer shallower water.

Another deep-sea fish found in the Gulf of California is the grenadier [grin-a-deer]. Grenadiers are some of the most common deep-sea fish in the world, with lots of different species. Some researchers estimate that they may make up as much as 15% of all fish that live in the deep sea. All grendadiers have large heads with big eyes and mouths, slender bodies that taper to such a thin tail that some people call the fish rattail.

The grenadier has barbels under the chin with chemoreceptors on them, and more chemoreceptors on the mouth and head, so it can sense other fish nearby even if it can’t see them. It’s been found as deep as nearly 23,000 feet under the surface, or 7,000 meters, which is just ridiculous. That’s four and a third miles underwater, or seven km. The Gulf of California isn’t that deep, of course, but there are grenadiers swimming around in the deepest areas, eating anything they can catch.

Some grenadiers are eaten, but mostly they have a soft, unpleasant texture and are low in protein. The biggest grenadier, which is common throughout the deep areas of the Pacific Ocean, is the giant grenadier, which can grow to 6 ½ feet long, or 2 meters. It eats vampire squid and other cephalopods. The grenadier most commonly found in the Gulf of California is the smooth grenadier, which only grows to about a foot long, or 30 cm.

A type of batfish that’s common off the western coasts of North, Central, and South America is also found in the deep sea of the Gulf of California. It’s a small type of anglerfish, only about six inches long, or 15 cm, dark in color, with a broad flattened head tapering to a much thinner long tail. Like other anglerfish, it has strong, stiff fins that it uses to crawl around on the ocean floor, where it hunts small animals like polychaete worms and crustaceans as well as fish.

If you look at the pictures I have in the show notes, or if you’ve been paying attention to the descriptions of all these fish, you’ll notice that even though they’re not related, they all share similar features. Their heads are large and usually broad, while their bodies are relatively small with a slender tail. The large head allows the fish to have unusually large gills and eyes, with a broad mouth so it can gulp down any food it finds. You know what this points to? That’s right, convergent evolution, where the fish all share a similar habitat that has influenced certain aspects of the body shape!

Currently, researchers are exploring volcanic vents in the Gulf of California that are the deepest found in the area. The area contains hydrothermal vents, which can heat the water to over 660 degrees F, or 350 degrees Celcius, and cold seeps, which are only called cold because they’re not super heated.

The vents are surrounded by mineral towers called hydrothermal chimneys that are up to 120 feet high, or 37 meters. These deepest vents and chimneys were only discovered in 2015, with others nearby only discovered in 2012. There are two types of chimneys in the area, dark-colored ones that grow the biggest, which are made up of sulfide minerals, and smaller, more delicate ones made up of light-colored carbonate minerals. The only other carbonate chimneys ever found are in the Atlantic. They’re really pretty.

Between the super heated water, the high levels of sulfides and heavy metals from the vents, and the great depth, the area would kill most animal life. But hydrothermal ecosystems are home to extremophiles that thrive in places that are deadly to other animals. The dark-colored chimneys, often called black smokers since they give off plumes of superheated minerals that look like smoke, are home to giant tube worms that can grow nearly eight feet long, or 2.4 meters, although they’re only a little more than an inch and a half wide, or 4 cm.

Giant tube worms don’t have a digestive tract, just a sort of internal pouch to hold the chemosynthetic bacteria that provide nutrients to the worm. The worm gives the bacteria a safe place to live, and the bacteria convert the carbon dioxide, hydrogen sulfide, and other minerals into nutrients that the worm absorbs.

But how do giant tube worms find new hydrothermal vents? Old vents go cold and new ones open up all the time, and giant tube worms can’t move once they’ve attached themselves to a rock or other solid structure. It turns out that newly hatched giant tube worms are free-swimming larvae, and at first they don’t contain any of the symbiotic bacteria that they need later in life. They acquire the bacteria later, when bacteria in the water find the larva and burrow into its skin. The larva swims deeper into the ocean and finds a hydrothermal vent, if it’s lucky, and attaches itself to a rock or something nearby. It then develops rapidly from a larva into the juvenile stage, where its digestive system reforms into a place for the bacteria to live. Then it grows into an adult tube worm.

The carbonate chimneys have a different kind of tube worm that prefers a different range of minerals.

Giant tube worms were only discovered in 1977. No one back then dreamed that anything could live around hydrothermal vents so the team exploring some vents hadn’t even brought along a biologist, just geologists. I like to think that they freaked out when they saw tube worms and other animals living around the vents.

It just goes to show, like they say in Jurassic Park, life finds a way.

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 113: Horned Hares and Winged Cats

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It’s April Fool’s Day, but while these two mystery animals may mostly be associated with hoaxes and tall tales, there’s a really interesting nugget of truth in both.

Unlocked Patreon episode about mammals with nose horns

Further reading: Dr Karl P N Shuker’s blog post about winged cats and his blog post about horned hares

Traditional drawings of horned hares:

You can take classes in taxidermy that specialize in making jackalopes!

A genuine horned hare (with an extreme case of SPV):

A winged cat:

Mitzi/Thomas the winged cat:

Show transcript:

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

This episode releases on April Fool’s Day, April 1. I’m not a fan of April fool jokes, so we’re going to discuss two interesting strange animals that turned out to be hoaxes—but hoaxes with a nugget of truth that’s actually more interesting than the hoax.

The first hoax is akin to the jackalope and it’s pretty obvious to us nowadays. The horned hare was a tradition in European folklore and drawings of it look like a jackalope. There are even stuffed horned hares, just as there are stuffed jackalopes.

Some of you may be wondering what the heck a jackalope is, so I’ll explain that first.

The jackalope legend may have started as a tall tale, but was probably just a taxidermy joke. When someone prepares a dead animal for taxidermy, it’s not a simple process. The taxidermist has to remove the skin from the body, clean it and add preservatives, make a careful armature or mannequin of the body out of wood or other materials, and put the skin on the armature and sew it up. The taxidermist then adds details like glass eyes and artificial tongues. It can take months of painstaking work to finish a specimen, and it requires a lot of artistry and training. Taxidermists who are learning the trade will often mount small, common animals like rabbits and rats as practice. And sometimes they’ll get creative with the process, just to make it more interesting. For instance, a taxidermist may add pronghorn antelope horns to a jackrabbit. Voila, there’s a jackalope!

You can see stuffed jackalopes today in a lot of places, since they’re fun conversation pieces. Some restaurants will have one stuck up on a wall somewhere, for instance. Horned hares are similar, but instead of a jackrabbit with pronghorn horns or white-tailed deer antlers, which are animals from North America, the European horned hare is usually a European hare with horns [I should have said antlers] from a roe deer.

The horned hare was such a common taxidermied animal that people actually believed it was real. Eventually, around the 19th century, as knowledge of the natural world grew more sophisticated, scientists realized rabbits and hares don’t have horns and those stuffed specimens were just hoaxes. The tip-off was probably when taxidermists started getting really fancy and adding bird wings and saber teeth to their mounted hares.

But…

The horned hare goes way back in history. It appeared in medieval bestiaries, sometimes called the unicorn hare. The unicorn hare was supposed to have a single black horn on its head. The hare would act normal, but when someone approached, it would spring at them and stab them with its horn. Then it would eat them. The legend of the horned hare is so widespread and long-lived, in fact, and was believed for so long, that it’s easy to think maybe it was based on something real. I mean, we just talked about rodents with nose horns a few weeks ago, so nothing’s impossible.

Wait, I think that’s a Patreon episode. If it is, I’ll unlock it. I’ll put a link in the show notes.

There is a strange truth behind all the jackalopes and horned hares. A disease called the Shope papilloma virus, or SPV, affects hares and rabbits. There are a lot of papilloma viruses in various animals, even humans, but in most animals, including humans, it only results in tumors in the body. In rabbits and hares, it causes keratinized tumors to grow from the skin, often on the head. Usually these are small and don’t show through the fur, but sometimes an animal has an extreme case of SPV and it genuinely looks like it has horns. The horns are hard and usually dark in color. As if that wasn’t bad enough, rabbits and hares in Europe can also get a disease called Leporipoxvirus that again causes facial horns to grow from the skin.

If you’re feeling totally creeped out right now, don’t worry, humans can’t catch these diseases from rabbits and hares.

Remember how I mentioned taxidermied hares with wings? What about cats with wings—but not taxidermied, real live domestic cats with fur-covered wings. That totally can’t be real, right? It’s not real?

It’s real…but only if you are really generous with what you mean by wings.

Winged cats are a real phenomenon, but the wings in question are furry, not feathered, and winged cats can’t fly. That doesn’t stop people from claiming they’ve seen these winged cats flying around causing mischief. For instance, in Ontario, Canada in 1966 a so-called vampire cat was supposedly flying around attacking other animals. It was a black tomcat with furry wings 7 inches long, or 18 cm. Eventually someone shot the cat, which was examined by veterinarians and found to be rabid. Its wings were nothing but thickly matted fur, so the stories of it flying around weren’t true, although sadly, it was definitely attacking other animals due to having rabies.

In 1959, a case went to court in West Virginia over a winged cat. A 15 year old boy named Douglas Shelton said he’d rescued the cat from a tree and adopted her. But a woman named Mrs. Hicks said that the cat was hers, named Mitzi, but that Mitzi had run away and she wanted her back. This makes sense. I mean, I would want my cat back too. At first the judge awarded the cat to Mrs. Hicks, but when Douglas brought her into the courtroom, she had no wings. Douglas said she’d shed them during the summer but he’d kept the wings, which he showed to the judge. At that point, Mrs. Hicks suddenly decided she didn’t want the cat after all. Frankly, I’m sure Mitzi was better off with Douglas, who didn’t care if she had wings or not, although he did change Mitzi’s name to Thomas.

Stories like these didn’t just happen back in the olden days. There are lots of winged cat reports today, including photos and videos. What’s going on? Why do some cats develop these furry appendages that people call wings?

Sometimes the cats in question just have long fur that has become unusually matted and appears to form winglike flaps along the sides. But in many cases, the wings are due to a rare skin condition called feline cutaneous asthenia, or FCA.

Cats with FCA have unusually elastic skin. All skin stretches at least a little bit but almost immediately snaps back into place. You can try this yourself by gently tugging up the skin on the back of your hand and releasing it. But in cats with FCA, the skin doesn’t snap back properly, especially the skin along the shoulders and back. Since in the ordinary course of living its life, a cat’s skin stretches quite a bit along the back, eventually an FCA cat ends up with long flaps of furry skin that stretched and didn’t snap back repeatedly. The wings aren’t really wings, of course, and can’t allow the cat to fly.

Cats with FCA do usually need special care, especially if the case is severe. The skin is elastic, but it’s also prone to damage because it’s actually very delicate. The so-called wings sometimes tear off naturally, leaving wounds that bleed very little but still need to be treated by a veterinarian. They then reform. The wings tend to be on the sides near the hind legs but are sometimes closer to the shoulders.

Mitzi, AKA Thomas, was definitely a cat with FCA. Her wings were six inches long, or 15 cm, and her tail was described as squirrel-like. She was a white cat described as a Persian, although she may have just had long hair like a Persian cat. A reporter who examined Thomas described her wings as fluffy at the ends but with a gristly feel at the base, as though they contained tendons or other structure. This was probably the extended skin due to FCA.

It sounds like Douglas was a really nice kid who rescued the cat from the tree and took her home, and when his friends made fun of the unusual-looking cat, he was really upset. Once word of the winged cat got around, people started showing up at the family’s house to look at it. At first Douglas charged 10cents to see the cat, and he was even invited to New York where he and Thomas appeared on the Today Show.

But after that, things started to go kind of nuts. Thousands of people kept trying to see the cat, so many that Douglas’s mom spread the story that the cat had died, just so people would leave the family alone. She also took the cat to a friend’s house for a while until the fuss died down, swearing the friend to secrecy that the cat was still alive. Then Mrs. Hicks sued.

I tried to find out what happened to Douglas Shelton and Thomas after all the excitement died down. Douglas and his family were awarded custody of Thomas by the judge, with Mrs. Hicks rewarded a single dollar in damages, but whatever happened after that has vanished into the pre-internet vacuum. I’m sure Thomas lived a good life with the Sheltons, and Douglas is probably still alive today. He would be about the right age to be a granddad by now, so I bet he tells his grandkids stories about the time he had a cat with wings. I bet they don’t even believe him.

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 112: The Bullfrog and the Raven

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I am sick and sound like a frog, or possibly a raven, so here’s a croaky episode about both!

Thanks to Corbin Maxey of Animals to the Max and Simon for their suggestions!

A bullfrog:

A common raven:

A baby raven:

NOT a baby raven (it’s probably a corncrake):

Show transcript:

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

Guess who has a cold! That’s right, I do! If this is the first episode you’ve ever listened to, I promise I don’t ordinarily sound like this.

Because my voice is such a mess, let’s have a short episode this week and learn about two animals that sound kind of like I do right now: the bullfrog and the raven. Thanks to Corbin Maxey of the great podcast Animals to the Max who suggested frogs, and friend of the pod Simon who suggested ravens, both of them in response to my complaining on Twitter that I had a sore throat. Little did they know what I would sound like a few days after that tweet!

Let’s start with the bullfrog. The American bullfrog is a species of frog. You probably figured that out without me needing to tell you. It originally only lived in eastern North America, but it’s been introduced in many other parts of the world. The reason it’s been introduced elsewhere is that it’s raised as food—specifically, it’s raised for its hind legs, which are considered a delicacy. It’s also sometimes kept as a pet. Sometimes it escapes from captivity and sometimes it’s just released into the wild by people who don’t know any better. In many places it’s become an invasive species that outcompetes native amphibians.

The bullfrog is a big, heavy frog. It can grow up to eight inches long from nose to butt, or 20 cm, but the hind legs are much longer. It can also be up to 1.8 pounds in weight, or 800 grams. Because the bullfrog has such long, strong legs, it can jump up to ten times the length of its own body.

The bullfrog is olive green in color, sometimes with darker blotches or stripes. The belly is pale and the lower part of the nose along the upper edge of the mouth is often bright green. Males usually have yellow throats, or technically yellow gular sacs. This is the sac the male inflates in order to make his loud croak.

Male bullfrogs have territories in swampy areas that they defend from other males, but the territories aren’t very large, maybe 20 feet apart from each other at most, or 6 meters. The males tend to move around and gather in groups during the breeding season, though, which is usually spring and early summer. The males croak loudly to attract females, and sometimes wrestle each other to show who’s stronger.

The female bullfrog lays her eggs in shallow water with plenty of plant cover. If the temperature isn’t too warm or too cold, the eggs hatch in about five days into tadpoles. The tadpoles have gills and teeth, although at first they don’t use their teeth for anything. They eat algae and other tiny food at first, and as they grow bigger, they start catching larger food.

In warmer climates, the tadpole starts to metamorphose into a frog in a few months. In colder climates, the tadpole can take up to three years to grow into a frog.

A full-grown bullfrog will eat anything it can swallow, not just insects. It’ll eat mice and other rodents, bats, birds, other amphibians, crawdads, snails, fish, and small reptiles. It uses its long sticky tongue to catch its prey, then clamps its jaws shut so the prey can’t escape. If part of the prey is sticking out of its mouth, like a tail or leg, the frog uses its thumbs to cram the bits in. If the prey won’t quit struggling, the frog may jump into the water and swim around until the animal drowns. They should call them sharkfrogs, not bullfrogs.

A lot of animals eat bullfrogs, though, like alligators and various snakes, birds like herons and kingfishers, and river otters. I have personally seen a snapping turtle attack a bullfrog. That was creepy. Sometimes when something attacks a bullfrog, it will actually scream. This sometimes startles the predator enough that it lets go, and the bullfrog can escape. Bullfrogs show some resistance to snake venom too.

The bullfrog gets its name from its voice, not its size. It sounds like this:

[bullfrog croaking]

Next, hopefully I will not lose my voice before I finish talking about the raven. There are a number of different raven species but they all look similar. They’re big black birds with heavy bills and deep, raspy voices. They look like a buff crow. We’ll talk about the common raven today, which lives throughout the northern hemisphere: that means North America, Greenland, and most of Eurasia.

The common raven can grow up to 26 inches long, from bill to tail, or 67 cm, with a wingspan over four feet wide, or 150 cm. Its feathers are glossy black, with purplish or blue iridescence in sunlight. Young ravens look similar but are not as glossy. Sometimes you’ll see a picture online of a little black poof of a baby bird labeled as a baby crow or raven, but that’s a mistake. Baby ravens have sleek feathers, not downy feathers. I’ll put pictures in the show notes so you can see the difference.

The raven is an omnivore, which means it pretty much eats anything it can get. It will eat roadkill and other carrion, fruit and grain, insects, small animals, other birds, and eggs. It’s also extremely smart, which means it can figure out how to get into trash cans and other containers to find food humans think it secure. If a raven finds a good supply of food, it will call other ravens to join in the feast. This usually happens when a younger raven finds food and calls its friends, even if the food source is being guarded by a mated pair of adult ravens. Those pesky kids.

Ravens mate for life, but younger birds who haven’t paired off usually live in flocks. They’re devoted family birds, with grown young of a pair sometimes hanging around to help their parents raise the next nest. The raven lives a long time, up to 21 years in the wild and over 40 years in captivity.

The only animals that eat ravens are large owls and eagles, and even that’s rare. Ravens are big enough, strong enough, and smart enough to defend themselves.

Ravens are extremely intelligent birds. Research suggests that they may even have something approaching an actual language. They can certainly reason and deceive each other, and demonstrate empathy in their interactions with other ravens. They also use tools to help get food, and are well known to play with items, sometimes making toys out of twigs or other items to play with as a group. Young ravens in particular are curious and will steal shiny things.

Ravens can imitate other animals and birds, even machinery, in addition to making all sorts of calls. It can even imitate human speech much like parrots. If a raven finds a dead animal but isn’t strong enough to open the carcass to get at the meat, it may imitate a wolf or fox to attract the animal to the carcass. The wolf or fox will open the carcass, and even after it eats as much as it wants, there’s plenty left for the raven.

But ravens also communicate nonvocally with other ravens. A raven will use its beak to point with the way humans will point with a finger. Incidentally, dogs understand what pointing means, but wolves don’t. Just throwing that in there. They’ll also hold something and wave it to get another raven’s attention, which hasn’t been observed in any other animal or bird besides apes.

I will soon be reduced to communicating nonvocally if I don’t stop and rest my voice. So I’ll shut up and let you listen to a real raven:

[raven sound]

You can find Strange Animals Podcast online at strangeanimalspodcast.com. blah blah blah I’m not saying it this week. My throat hurts.

Thanks for listening! Next week hopefully I’ll be all better and sound like a human again instead of like a frog or a raven.

Episode 111: Poisonous moths, venomous bugs

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Let’s get gross and horrible this week! Are there any bugs with so much venom they could kill you? What would happen if you ate 5,000 moth digestive tracts? Why am I even talking about this stuff? Listen and find out! Thanks to Grady and Tania for today’s topic suggestions!

The giant silkworm moth caterpillar. Do not touch. No seriously, don’t! You might d i e

The southern flannel moth and its larva, a puss caterpillar. Fuzzy, yes, but don’t pet the caterpillar:

A luna moth and its caterpillar. It will not kill you:

A bullet ant. Look at those chompers!

The white-spotted assassin bug. At least you can see it coming:

Show transcript:

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

This week’s episode is a suggestion from Grady, who also sent several other really good suggestions we’ll hopefully get to soon. The one we’re looking at this week is poisonous bugs! And because another listener, Tania, suggested we cover moths, we’ll also make sure to talk about a lot of poisonous or venomous moths too.

Technically, if an insect is poisonous that means it will make you sick if you eat it. If an insect bites or stings you and it injects poison into the wound, it’s referred to as venomous. But you can call both poisonous because everyone will know what you mean. Also, you would probably get sick if you ate a venomous bug too, now that I think about it.

You might think I’m joking when I talk about eating bugs, but in many parts of the world people do. If you think about it, it’s no weirder than eating shrimp, lobster, oysters, or eggs. Remember that humans are omnivores, and that means we will eat just about anything. Those things don’t all have to be cookies and peanut butter sandwiches, although I haven’t had my lunch yet and if I had to choose between a PB&J with maybe a couple of Thin Mints afterwards, I’d choose that over a big bowl of deep-fried crickets. But lots of people would choose the crickets. It all depends on what you’re used to and what’s considered acceptable in your culture.

But even in areas where people eat lots of insects, they don’t eat every kind of insect. Some really are poisonous because they eat plants that contain toxins and store those toxins in the body. The monarch butterfly caterpillar eats milkweed, which contains poisons that can harm the heart, so don’t eat monarch butterflies. But because insects are generally quite small, the toxins one insect can hold aren’t usually enough to make you really sick unless you eat a whole bunch of them. That’s why children in some parts of Italy can eat a particular moth without dying even though it contains the deadly poison cyanide.

You know what? Let’s start with this moth, because what the heck, Italian children. Why are you eating these moths anyway, and why are you not dying of cyanide poisoning?

There are a number of closely related moth species that children in the Carnia region of Italy traditionally eat. The moth’s wingspan is only about an inch wide, or 30 millimeters. It’s most common in the Italian Alps and it flies around during the day, which makes it easy to find and catch. Its body is grayish, and one pair of its wings are greenish or gray with red spots, while the other pair of wings is mostly red. There’s also a variety with yellow wing markings instead of red. The reason it has such bright colors is because it stores a liquid containing cyanide in its digestive system, and the bright colors tell potential predators to leave it alone, it’s poisonous.

The problem is, the moth’s digestive system also contains sugars called glucosides, which makes it taste sweet. And before you laugh at little Italian children catching moths to eat because they’re sweet-tasting, think about how much effort you may have put into extracting a tiny bead of nectar from honeysuckle blossoms.

But honeysuckle doesn’t contain cyanide. Why don’t those little moth-eating kids get sick?

Researchers have studied this, mostly because they were worried about the children. It turns out that there’s so little cyanide in each moth that even a small child would have to eat at least 170 moths whole in a short period of time to die. Since most of the time the kids pull the moths apart and only eat the tiny piece of the digestive tract that contains sugar, that reduces the amount of cyanide they ingest. A kid would have to eat 5,000 moth digestive tracts to die, and frankly if a kid was that determined to have that much sugar, they’d probably be more likely to spend their time doing odd jobs for money to buy candy instead of catching thousands of moths.

Well, that was gross. I feel like we’re off to a really good start in this episode.

So, eating 5,000 moth digestive tracts aside, are there any bugs out there that are so venomous that they could kill you?

Yes there are. But you’re probably not going to run across them, and even if you do, you’re probably going to be just fine. It’s rare that someone dies after touching Lonomia moth caterpillars, although it does happen. But if you do touch one of the caterpillars, even if you don’t die, you’re not going to feel very good.

There are a number of Lonomia species. The adult moths are brown or grayish, with the males sometimes yellow. It has delicate darker brown markings to help it mimic small dead leaves. The species that is most venomous is sometimes called the giant silkworm moth, Lonomia obliqua, and it lives in South America. It’s especially well known in southern Brazil. The caterpillar grows to about two inches long, or 5.5 cm, and is either green or brown with lots of hair-like spines growing from the back and sides.

A lot of caterpillars have these hair-like spines, and most of them aren’t venomous. They can cause a rash, though, since the spines are very thin, detach easily, and can irritate the skin. But the caterpillar of the giant silkworm moth has spines with powerful venom. The venom contains an anti-clotting agent that causes internal bleeding that can eventually lead to death. But one little caterpillar doesn’t contain enough venom to kill a person all by itself. The trouble comes when the caterpillars are gathered in groups on leaves or tree trunks, because then it’s easier for someone to accidentally touch a bunch of caterpillars at once, receiving hundreds or even thousands of tiny stings from the venomous hairs. Fortunately, the mortality rate for people who are stung by these caterpillars is only a little over 2%. That means almost 98% of people stung by one survive.

Another moth with a venomous caterpillar lives in the United States, especially the southeastern states. It’s called the southern flannel moth and it’s really pretty and fuzzy, yellow and white with some brown markings. The caterpillar is often called the puss caterpillar because it’s also fuzzy and somewhat resembles the end of a cat’s tail or a cat’s paw. But don’t touch it! The puss caterpillar has spines with venom sacs at the base just like the giant silkworm moth caterpillar has. If someone brushes against the spines, they inject venom into the skin. The puss caterpillar isn’t deadly, and most people who touch it only end up with a painful swelling at the injection site that feels like an extra bad bee sting. But some people have a more severe reaction, including fever, vomiting, and heart trouble.

Incidentally, in case you were wondering if caterpillars poop, of course they do. Some caterpillars, though, including the puss caterpillar, actually eject fecal pellets so that they fly away like tiny bullets of poop. This is partly so the caterpillar doesn’t make a mess on the leaf it’s eating, but mainly so that predators aren’t able to find the caterpillar after seeing or smelling its poop. But sometimes the puss caterpillar will fire fecal pellets at predators, so that’s yet another reason not to touch one.

Puss caterpillars build really tough cocoons, so tough that they can stay on a tree or bush for years after the moth is long gone. Some ant species actually move into puss caterpillar cocoons to raise their eggs. Spiders also sometimes live inside empty puss caterpillar cocoons.

There are other venomous moth caterpillars, but they’re all pretty similar to the ones we’ve discussed already. But while we’re on the subject of moths, let’s talk about just how amazing and weird they are. This goes for butterflies too, of course, which are very similar.

As an example, let’s discuss a type of moth that isn’t venomous or poisonous or dangerous in any way, the luna moth.

The luna moth is one of the largest moths in North America, and it’s fairly common in the eastern part of the continent. It’s beautiful, with pale green wings and a white body. Its wingspan can be as much as seven inches across, or 18 cm. The wings have yellow eyespots and long swallowtails that confuse bats’ echolocation by fluttering as the moth flies, scattering the reflections of the bat’s echolocation calls. The bat attacks the swallowtail instead of the moth’s body, allowing the moth to fly away.

This is the life cycle of the luna moth, which is similar to most moths’ life cycles. A female moth will lay several hundred eggs on the undersides of leaves the caterpillars will eat, usually only one or a few eggs per leaf spread across many trees. The luna moth caterpillar especially likes persimmon, sweet gum, wild cherry, hickory, willow, black walnut, and white birch trees. The eggs hatch into little green caterpillars after about a week. The caterpillars eat leaves, grow big enough to molt, eat and grow some more, molt again, and so on. The period between molts is called an instar, which in the luna moth is about a week, give or take. After five instars, the caterpillar is as big as it will get, generally around 3 ½ inches long, or 9 cm. It’s not dangerous, but if a predator approaches, it will rear up, clack its mandibles, and puke up the contents of its digestive system, which stinks.

Finally, the caterpillar leaves the tree where it’s lived its whole life and crawls around in the leaf litter underneath the tree. There it spins a cocoon out of silk, wrapped inside leaves to hide it, expels any water or food still in its intestines, and transforms within the cocoon into a pupa. The pupal stage takes about two or three weeks, and let’s find out what’s going on inside the cocoon during that time.

First, the pupa is encased in a sort of exoskeleton called a chrysalis, which is inside the cocoon. Within the chrysalis, the caterpillar’s body starts to digest itself using its own digestive juices. This breaks its body down into cells in a sort of soup inside the chrysalis, and the cells then reform into the adult moth or butterfly.

Clearly, if you go through a metamorphosis like this that requires all your cells to turn into cell soup, you aren’t going to retain any memories from before you ensouped. Right? Well, according to a 2008 study with a moth called the tobacco hornworm, caterpillars that learned to avoid a particular odor retained those memories as full-grown moths. The moths would also avoid that odor. Researchers aren’t sure how this happens and I wasn’t able to find any follow-up studies, but it’s pretty mind-blowing. My brother sent this article to me ages ago, so thanks, Richard!

So, the luna moth has developed from a caterpillar into caterpillar soup and then into a newly-formed luna moth. The moth has serrated spurs made of chitin at the base of the front wings, which it uses to tear its way out of the cocoon. Its new wings are soft and wet, so it will spend a couple of hours waiting for the wings to harden before it can fly.

Male luna moths usually hatch first and fly away to find females. When a female luna moth hatches, she flies around until she finds a tree she likes, and then she stays in the tree and releases pheromones once it grows dark. Pheromones are chemicals that attract males, which is why the male moth has wider antennae than the female. He detects pheromones with his antennae, and can sense them up to six miles away from the female, or about 11 km. After he finds her, the pair mate, and within a day or so she starts laying eggs.

Like many moth species, adult luna moths don’t eat. They only have vestigial mouths and no digestive system at all. They mate, lay eggs, and die within about a week of hatching.

The luna moth is harmless even if you eat it or pet it—please don’t do either—but it is related to the deadly giant silkworm moth of South America. Fortunately, they look totally different and live in different places.

One last note before we leave moths behind and look at some other venomous insects. Back in episode 93 where we talked about some of the biggest insects in the world, I mentioned the queen alexandra’s birdwing butterfly. I put a picture of it in the show notes, or so I thought. Listener Judith caught my mistake and pointed out that the picture I’d posted was actually of an atlas moth. The atlas moth is in fact bigger than the queen alexandra’s birdwing butterfly, with a wingspan just shy of a foot across, or 30 cm. I swapped out the picture so it’s correct, so thank you to Judith for letting me know!

Now let’s take a look at some venomous insects that aren’t moths. Let’s just skip right over the ones you know about, like bees, and talk about a few interesting ones you might not have heard of. Like the bullet ant. It gets its name because its bite is so painful it feels like you’ve been shot with a gun.

The bullet ant lives in the rainforests of Central and South America. Worker ants are about an inch long, or 3 cm, which is pretty darn big for an ant. The queen ant is about the same size as the worker ants. It’s not closely related to any other ants alive today, but an ant discovered in amber dated to at least 15 million years old was determined to be the bullet ant’s closest relative. The bullet ant looks more like a wasp without wings than an ant, in fact. It’s black in color with massive jaws.

The bullet ant’s bite is considered the most painful of any insect. The ant injects venom with the bite that causes a burning pain throughout the body that lasts for a solid 24 hours without fading. It won’t kill you, but you may wish you were dead. The venom is a neurotoxin that can cause temporary paralysis of the part of the body that was bitten too.

An indigenous people of Brazil, the Sateré-Mawé, use the bullet ant bite in an initiation rite for warriors. That’s how much the ant’s bite hurts.

Finally, let’s learn about an insect with a terrifying name, the assassin bug. There are a lot of assassin bug species throughout the world, and while they sound scary, they can’t actually kill you. Their bite might hurt, but compared to a bullet ant bite, pffft. Easy peasy. But the white-spotted assassin bug of Africa does something the bullet ant only wishes it could do. If something disturbs a white-spotted assassin bug, it can spit venom. And if any of the venom gets into your eyes, it can temporarily blind you.

Assassin bugs mostly eat other insects. Some specialize in hunting spiders, some in hunting bedbugs or cockroaches. The assassin bug has a strong proboscis, or rostrum, that it uses to stab its prey and inject venom containing digestive enzymes. The venom paralyzes the insect and the digestive enzymes liquefy its insides. The assassin bug slurps up the liquefied insect insides. But if a predator attacks the assassin bug, it will inject a different kind of venom that causes intense localized pain and kills off the tissue around the injection site. No other insects are known to produce two different types of venom.

Some people keep assassin bugs as pets. What is wrong with those people?

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 110: Three mystery animals from India

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Thanks to Pranav for this week’s suggestion! We’re going to look at three mystery animals from India, ones you may not have heard of.

A photograph reportedly of a kallana pygmy elephant, although scale is hard to tell:

A pink-headed duck, deceased:

Show transcript:

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

It’s time for a mystery animals episode, and this one was a suggestion from Pranav, who suggested mystery animals from India. Pranav also gave me lots of other excellent suggestions that I’ll hopefully get to pretty soon.

When I got the suggestion, I realized the only mystery animal from India I really knew about was one we talked about in episode 55, the buru. I had no idea what else might be hiding in the forests and mountains of India. Apologies in advance for undoubtedly mangling names and places from India. I tried to look up pronunciations to at least make an effort to get them right.

India is in south Asia, and it’s a huge country. The area is often referred to as the Indian subcontinent because it mostly sits on its own tectonic plate. Around 100 million years ago it was connected with Madagascar, then split off around 75 million years ago and for many millions of years it was a giant island. But it moved northward slowly—and we’re talking only around 8 inches a year, or 20 cm, which is actually pretty fast for a tectonic plate—and slowly crashed into Eurasia, shoving beneath the Eurasian plate and causing it to crumple upwards, creating the Himalayas.

About half of India’s landmass projects southward into the Pacific Ocean like someone dipping their foot into a bath to see if it’s too hot. As a result, the country has a lot of coastland. So there are amazingly high mountains to the north, tropical coasts to the south, and everything from desert to tropical rainforest in between. It even has some volcanic islands off its coast. It pretty much has everything you could want in a country, and that means it has an amazing variety of animal life too.

Many of India’s animals are ones everyone is familiar with from zoos and storybooks: elephants, tigers, rhinoceroses, cobras, pangolins, and lots lots lots more. But it also has its share of mystery animals. We’ll look at three of those mystery animals today. I think you’re going to like all three of them.

Let’s start with the mande burung. It’s supposed to be a giant ape-like animal as much as 8 or 10 feet tall, or up to 3 meters, with black hair. It lives in the remote forests of northeast India—specifically, in Meghalaya.

The mande burung has long been a creature of folklore in the area, until November 1995 when someone saw one. But I can’t find any information at all about what that sighting entailed. Interest in the mande burung has increased steadily since then, with cryptozoologists from India and other parts of the world mounting expeditions to look for it. They report finding footprints up to 15 inches long, or 38 cm, hair from unidentified animals, and nests made from leaves and grass. But there are no photographs of the animals, no mande burung feces, no dead bodies, and very few sightings, all of them within the last few decades and some of them decidedly questionable.

It’s certainly possible that there’s a mystery animal living in the area. Meghalaya is heavily forested outside of the cities and farmland. Some areas of forest are considered sacred, so they’ve never been logged, no one’s ever lived there, and no one hunts there. As a result, these sacred forests contain some of the richest habitats in all of Asia, containing plants and animals that live nowhere else. Meghalaya also has wildlife sanctuaries. So it’s pretty much guaranteed that there are animals living in Meghalaya that are unknown to science.

But while Meghalaya is primarily an agricultural region, tourism is becoming more and more important. A 2007 press release even talks about how the mande burung legend will bring more tourists to the area, and that a local group had started offering tours for people looking for the mande burung. That doesn’t mean the sightings aren’t genuine—I think most of them are—but as I’ve said many times, people see what they expect to see. The more people talk about the mande burung, the more likely people will think of it when they see a large animal they can’t identify. And there are lots of big animals living in the forests of Meghalaya, including an endangered species of gibbon, four species of macaque, and three species of bears. Any of these might resemble a bigfoot type of creature if seen in low light or poor conditions.

In 2001, a hair found in what’s called a “cedar tree root den” was DNA tested. Bear and human DNA was ruled out, and the DNA results didn’t match any known animals. But a follow-up test in 2008 gave a result that was just as surprising to scientists: the hair belonged to a Himalayan goral, a bovid that wasn’t known to live in the area until the DNA results came in. The goral is a small antelope-like animal with short horns that lives in the southern slopes of the Himayalas. It’s dark gray or gray-brown in color with a darker eel stripe along the spine. Generally, websites that like to talk about Bigfoots mention the first DNA test but don’t mention the follow-up, but I think the discovery of Himalayan goral hairs in Meghalaya is exciting. Who knows what else might be hiding in the forests too?

For instance, maybe a pygmy elephant! Well, okay, reports of a suspected dwarf elephant species called the kallana come from southern India, not northeastern. But it’s definitely a mystery animal.

The Indian elephant is a subspecies of Asian elephant that lives throughout much of mainland Asia. It’s smaller than the African elephant but still pretty big, with males standing as much as 11.3 feet at the shoulder, or 3.4 meters, although most are much smaller than this. Females are smaller than males and have smaller tusks, or sometimes no tusks. It was once common throughout India but is now endangered due to habitat loss and poaching. Tame elephants help with farming and with carrying heavy items and human riders across uneven terrain, but the elephants aren’t actually domesticated.

The kallana elephant reportedly only grows to around five feet high, or 1.5 meters, and while it looks like an ordinary Indian elephant except for its size, it doesn’t mix with Indian elephants and even appears to avoid them. It lives in rocky hills in and around the Peppara Wildlife Sanctuary in southern Kerala. It’s shy and can move much faster than regular elephants, and it doesn’t appear to have trouble with steep slopes the way elephants usually do.

In 2005, a wildlife photographer named Sali Palode got pictures of two kallana elephants, one alive, one a dead one they found by a lake. He took more photos in 2010, and in 2013 he got brief video footage. But there are no photos of a herd of kallana elephants, just solitary animals. Without being able to examine a kallana elephant in person, researchers don’t know if the elephant photographed is a new species or subspecies, or just an Indian elephant with a genetic anomaly similar to dwarfism in humans. The photos might even just be of young elephants that haven’t grown to their full size yet.

Until someone gets definitive footage of a herd of Kallana elephants, an individual is captured and studied, or someone takes samples of the elephant dung found throughout the hills and sends it for DNA testing, there’s no way of knowing if the small elephants Sali Palode has photographed and the local tribespeople report seeing are something special. Not that regular elephants aren’t special enough already, but if there is a population of anomalous elephants in the area, it’s important to learn about them so they can be further protected.

Our final mystery animal of India is the pink-headed duck. It lives in wetlands in parts of eastern India and a few nearby countries, and it gets its name because the male has a pink head and neck. It builds its nests in dense elephant grass and its eggs are almost completely round. It’s shy and prefers remote, isolated areas with deep ponds or lakes and thick grass.

So why are we talking about the pink-headed duck in a mystery animals episode? Well, unfortunately, there hasn’t been a single confirmed sighting of the duck since 1949. Some researchers push this back ever farther to 1935. The main reason it hasn’t been classified as extinct is that the occasional report of one occasionally trickles in.

The difficulty in knowing whether there really are pink-headed ducks still alive out there is that the areas where they are known to have lived are really hard to get to. I mean, unless you’re a duck. Then they’re great. The decline of the species started in the 19th century when British big game hunters would come through and basically just shoot everything that moved. It was already considered rare by the turn of the 20th century, which made hunters even more eager to shoot it so they’d have a rare trophy. Habitat loss and trophy hunting drove it nearly to extinction even if it’s not actually already extinct.

Recent expeditions by conservationists and birders hoping to find some pink-headed ducks haven’t found any definitive proof that any are still alive. A 2017 expedition to Myanmar didn’t find any of the ducks, but the team did interview locals who said they’d seen the ducks as recently as 2010.

We don’t know a whole lot about the pink-headed duck. Researchers think it was a diving duck, but it may have been a dabbler. A dabbling duck tips its body forward, head underwater and tail sticking up, to forage in shallow water, often on plants. A diving duck dives for its food, usually small animals of various kinds. We know the pink-headed duck ate snails and plants, but it probably ate other things too that we don’t know about.

A study of a taxidermied pink-headed duck’s feathers in 2016 determined that the pink color came from carotenoids, a pigment that also gives the flamingo its pink color. The only other duck with feathers pigmented by carotenoids is the pink-eared duck of Australia, which is only distantly related to the pink-headed duck. It has a tiny pink spot on each side of its head.

Conservationists and birdwatchers hold out hope that the pink-headed duck is still alive, hiding its round eggs in clumps of elephant grass far away from humans. Some researchers have even suggested it might be nocturnal, which would explain why it’s always been hard to find. It was never much of a duck for moving around, preferring to stay put instead of flying off to other areas. Hopefully someone will discover a healthy population one day, possibly somewhere no one’s even looked yet, and we can protect it and learn about it before it’s too late. Once a duck is gone, a duck is gone forever.

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 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.

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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!