Episode 288: Mystery Invertebrates

Thanks to Joel for suggesting this week’s topic!

Happy birthday to Fern this week!

Further reading:

Small, rare crayfish thought extinct is rediscovered in cave in Huntsville city limits

Hundreds of three-eyed ‘dinosaur shrimp’ emerge after Arizona monsoon

An invertebrate mystery track in South Africa

The case of the mysterious holes in the sea floor

Contemplating the Con Rit

The Shelton Cave crayfish, rediscovered:

The three-eyed “tadpole shrimp” or “dinosaur shrimp,” triops [photo from article linked above]:

A leech track in South Africa [photo from article linked above]:

A track, or at least a series of holes, discovered in the deep seafloor [photos from article linked above]:

Show transcript:

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

Thanks to Joel who suggested we do an episode about mystery invertebrates! It took me a while, but I think you’re really going to like this episode. Some of the mysteries are solved and some are not, but they’re all fun.

Before we get to the mystery animals, though, we have a birthday shout-out! A great big happy birthday to Fern! I hope you have your favorite type of birthday cake or other treat and get to enjoy it with your loved ones.

Our first mystery starts in a cave near Huntsville, Alabama in the southern United States, which is in North America. Shelta Cave is a relatively small cave system, only about 2,500 feet long, or 760 meters. That’s about half a mile. It’s a nature preserve now but in the early 1900s it was used as an underground dance hall with a bar and everything.

Biologist John Cooper studied the cave’s aquatic ecosystem in the 1960s when he was doing his dissertation work. His wife Martha helped him since they were both active cavers. At the time, the cave ecosystem was incredibly diverse, including three species of crayfish. One was called the Shelta Cave crayfish, which was only a few inches long, or about 5 cm, mostly translucent or white since it didn’t have any pigment in its body, and with long, thin pincers.

It was rarer than the cave’s other two crayfish species, and unlike them it had only ever been found in Shelta Cave. From 1963 to 1975, only 115 individuals had been confirmed in repeated studies of the cave’s ecosystem.

Then, in the 1970s, several things happened that caused a serious decline in the diversity of life in the cave.

The first was development of the land around the cave into subdivisions, which meant that more pesticides were used on lawns and flower beds, which made its way into the groundwater that entered the cave. It also meant more people discovering the cave and going in to explore, which was disturbing a population of gray bats who also lived in the cave. To help the bats and keep people out, the park service put a gate over the entrance, but the initial gate’s design wasn’t a very good one. It kept people out but it also made it harder for the bats to go in and out, and eventually the bats gave up and moved out of the cave completely. This really impacted the cave’s ecosystem, since bats bring a lot of nutrients into a cave with their droppings and the occasional bat who dies and falls to the cave floor.

The gate has since been replaced with a much more bat-friendly one, but studies afterwards showed that a lot of the animals found in the cave had become rare. The Shelta Cave crayfish had disappeared completely. One was spotted in 1988 but after that, nothing, and the biologists studying the cave worried that it had gone extinct.

Then, in 2019, a team of scientists and students surveying life in the cave spotted a little white crayfish with long, thin pincers in the water. The team leader dived down and scooped it up with his net to examine more closely. The crayfish turned out to be a female Shelta Cave crayfish with eggs, which made everyone excited, and after taking a tiny tissue sample for DNA testing, and lots of photographs, they released her back into the water. The following year they found a second Shelta Cave crayfish.

The Shelta Cave crayfish is so little known that we don’t even know what it eats or how it survives in the same environment with two larger crayfish species. Biologist Dr. Matthew Niemiller is continuing Dr. Cooper’s initial studies of the cave and will hopefully be able to learn more about the crayfish and its environment.

Next let’s travel from a cool, damp, flooded cave in Alabama to northern Arizona. Arizona is in the western United States and this particular part of the state has desert-like conditions most of the year. Almost a thousand years ago, people built what is now called Wupatki Pueblo, a 100-room building with a ballcourt out front and a big community room. It was basically a really nice apartment building. Wupatki means “tall house” in the Hopi language, and while the pueblo people who built it are long gone, Wupatki is still an important place for the Hopi and other Native American tribes in the area. It’s also a national monument that has been studied and restored by archaeologists and is open to the public.

In late July 2021, torrential rain fell over the area, so much rain that it pooled into a shallow temporary lake around Wupatki, including flooding the ballcourt. The ballcourt is 105 feet across, or 32 meters, and surrounded by a low wall. One day while the ballcourt was still flooded, a tourist came up to the lead ranger, Lauren Carter. The visitor said there were tadpoles in the ballcourt.

There are toads in the area that live in burrows and only come out during the wet season when there’s rain, and Carter thought the tadpoles might be from the toads. She went to investigate, saw what looked like tadpoles swimming around, and scooped one up in her hands to take a closer look. But the tadpoles were definitely not larval toads. In fact, they kind of looked like teensy horseshoe crabs, with a rounded shield over the front of the body and a segmented abdomen and tail sticking out from behind, with two long, thin spines at the very end that are called caudal extensions. It had two pairs of antennae and lots of small legs underneath, some adapted for swimming. The largest of the creatures were about two inches long, or 5 cm.

What on earth were they, and where did they come from? This area is basically a desert. Carter stared at the weird little things and remembered hearing about something similar when she worked at the Petrified Forest National Park, also in Arizona. She looked the animal up and discovered what it was.

It’s called Triops and is in the order Notostraca. Notostracans are small crustaceans shaped sort of like tadpoles, which is why it’s sometimes called the tadpole shrimp, but it’s not a shrimp. It has two eyes on the top of its head visible through its flattened, smooth carapace. Species in the genus Triops also have a so-called third eye between the two ordinary eyes, although it’s a very simple eye that probably only detects light and dark. Many crustaceans have these third eyes in their larval forms but very few retain them into adulthood.

Notostracans have been around for about 365 million years, and haven’t changed much in the last 250 million years. It’s an omnivore that mostly lives on the bottom of freshwater pools and shallow lakes, often temporary ones like the flooded ballcourt, although some species live in brackish water and saline pools, or permanent waterways like peat bogs.

Triops eggs are able to tolerate high temperatures and dry conditions, with the eggs remaining viable for years or even decades in the sediment of dried-up ponds. When enough water collects, the eggs hatch and within 24 hours are miniature versions of the adult Triops. They grow up quickly, lay lots of eggs, and die within a few months or when the water dries up again.

Triops eggs are even sold as aquarium pets, since they’re so unusual looking and are easy to care for. They basically eat anything. They especially like mosquito larvae, so if you see some in your local pond or other waterway, give them a tiny high-five.

In 1996, some workers near Indianapolis, Indiana were servicing a tank full of chemical byproducts from making plastic auto parts when they noticed movement in the toxic goo. They investigated and saw several squid-like creatures swimming around. They were red-brown and about 8 inches long, or 20 cm, including their arms or tentacles, but were only about an inch wide, or 2.5 cm.

The workers managed to capture one and put it in a jar, which they stuck in the break room refrigerator. By the time someone in management arranged to have it examined by a scientist, the jar had been thrown out. If you’ve ever tried to keep food in a break room fridge, you’ll know that there’s always someone who will throw out everything in the fridge that isn’t theirs, no matter whether it’s labeled or brand new or not. I have had my day’s lunch thrown out that had only been in the fridge a few hours. Anyway, when the tank was cleaned out the following year, no one found any creatures in it at all.

This sounds really interesting, but there’s precious little information to go on. The story appeared in a few newspapers but we have no names of the people who reportedly saw the creatures, no follow-up information. It has all the hallmarks of a hoax or urban legend. The creatures’ size also seems quite large for extremophiles in a small, closed environment. What would they find to eat to get so big?

Next let’s talk about some mysterious tracks made by invertebrates, as far as we know. We’ll start with a track on land that was a mystery at first, but was solved. A man in the Kruger National Park in South Africa named Rudi Hulshof came across a weird track in the sandy dirt that he didn’t recognize. It was maybe 10 mm wide and kind of looked like a series of connected rectangles, as though a tiny person was moving a tiny cardboard box by rolling it over and over, but there weren’t any footprints, just the body track.

Curious, Hulshof followed the track to find what had made it, and finally discovered the culprit. It was a leech! Most leeches live in water, whether it’s the ocean, a pond or swamp, a river, or just flooded ground. Most species are parasitic worms that attach to other animals with suckers, then pierce the animal’s skin and suck its blood. The leech stays on the animal until it’s full, then drops off. Some leeches are terrestrial, but it appears that this one was a freshwater leech that had attached to an animal passing through the water, then dropped off onto land. It had crawled as far as it could trying to find a better environment, but when Hulshof found it it was dead, so it had not had a good day.

The leech moves on land by stretching the front of its body forward, then dragging its tail end up in a bunch kind of like a worm (it is a kind of worm), so that’s why its track was so unusual-looking. It’s a good thing Hulshof found the leech before something ate it, or else he’d probably still be wondering what had made that track.

We have photographs of other tracks that are still mysterious. You may have heard about one that’s been in the news lately. This one was found by a deep-sea rover in July 2022, more than a mile and a half deep, or 2500 meters, in the north Atlantic Ocean.

The track may or may not actually be a track, although it looks like one at first glance. It consists of a line of little holes in the seafloor, one after the other, although they’re not all the same distance apart. The rover saw them on two separate dives in different locations, so it wasn’t just one track, but although the scientists operating the rover remotely tried to look into the holes, they couldn’t get a good enough view. It does look like there’s sediment piled up next to the holes, so researchers think something might actually be digging the holes, either digging down from the surface to find food hidden in the sediment, or digging up from inside the sediment to find food in the water. The rover did manage to get a sample of sediment from next to one of the holes and a water sample from just above it, and eventually those samples will be tested for possible environmental DNA that might help solve the mystery.

This wasn’t the first time these holes have been seen in the area, though. An expedition in 2004 saw them and hypothesized that the holes are made by an invertebrate with a feeding appendage of some kind that it uses to dig for food. Not only that, we have similar-looking fossil holes in rocks formed from deep marine sediments millions of years ago.

Other deep-sea tracks have a known cause, and humans are responsible. In the 1970s and 1980s, ships with deep-sea dredging equipment traveled through parts of the Pacific Ocean, testing the ocean floor to see whether the minerals in and beneath the sediment were valuable for mining. A few years ago scientists revisited the same areas to see how the ecosystems impacted by test mining had responded.

The answer is, not well. Even after 40 years or so since the deep-sea mining equipment sampled the sea floor, the marks remain. The deep sea is a fragile ecosystem to start with, and any disturbance takes a long, long time to recover—possibly thousands of years. So while the holes discovered in 2022 were almost certainly made by an animal or animals, they might be quite old.

Let’s finish with a mystery animal we’ve talked about before, but a really long time ago—way back in episode 6. It’s definitely time to revisit it.

In 1883 when he was 18 years old, a Vietnamese man named Tran Van Con had seen the body of an enormous creature washed up on shore at Hongay in Vietnam. Van Con said it was probably 60 feet long, or 18 meters, but less than three wide wide, or 90 cm. It had dark brown plates on its back with long spines sticking out from them to either side, and the segment at its tail end had two more spines pointing straight back. It didn’t have a head, which had presumably already rotted off, or something bit it off before the animal washed ashore. It had been dead for a long time considering the smell. In fact, it smelled so terrible that locals finally towed it out to sea to get rid of it. It sank and that was the last anyone ever saw of it. The locals referred to it as a con rit, which means “millipede,” since the armor plates made it look like the segmented body of an immense millipede.

Lots of people have made suggestions as to what the con rit could be, but nothing really fits. It was the length of a whale, but it doesn’t sound like any kind of whale known. The armored plates supposedly rang like metal when hit with a stick. Even if this was an exaggeration, it probably meant the armor plates were really hard, not just the skin of a dead whale that had hardened in the sun. It also implies that the plates had empty space under them, allowing them to echo when hit. Zoologist Dr. Karl Shuker suggests that the plates might have been the exoskeleton of a crustacean of some kind, which makes a lot more sense than a whale, but the sheer size of the carcass is far larger than any crustacean, or even any arthropod, ever known.

There’s also some doubt that the story is accurate. It might even be a hoax. We only know about the con rit at all because the director of Indochina’s Oceanographic and Fisheries service, Dr. A. Krempf, talked to Tran Van Con about it in 1921. That was 38 years after Van Con said he saw the creature, so he might have misremembered details. Not only that, Krempf translated the story from Vietnamese, and there’s no way of knowing how accurate his translation was.

The con rit is also a monster from Vietnamese folktales, a sort of sea serpent that had lots of feet. It was supposed to attack fishing boats to eat the sailors, until a king caught it and chopped it up into pieces. A local mountain was supposedly formed from its head, and the other pieces of its body turned into the unusual stones found on a nearby island.

There’s always the possibility that Tran Van Con actually told Krempf this folktale, but that Krempf misunderstood and thought he was telling him something he actually witnessed. Then again, there are eight reports from ships in the area between 1893 and 1915 of creatures that might have been a con rit. One account from 1899 was a sighting of a creature estimated as being 135 feet long, or 41 meters, which was rowing itself along at the surface by means of multiple fins along its sides.

Whatever the con rit was, there haven’t been any sightings since 1915. That doesn’t mean there isn’t a population of incredibly long invertebrates living in the deep ocean in southeast Asia. If it does exist, maybe one day a deep-sea rover will spot one. Maybe it dug those little holes, who knows?

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 284: Billy Possum and Teddy Bear

Thanks to Pranav and Zachary for their suggestions this week, where we learn the story behind two cuddly toys and the animals that inspired them!

The cartoon that inspired the toy:

My own teddy bear:

An American black bear (not William Taft although yes, there is a resemblance, including a willingness to eat entire possums in one sitting):

William Taft:

A Virginia opossum:

A possum with babies!

Stop trying to make Billy Possum a thing:

Admittedly it was pretty cute:

Show transcript:

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

This week we’re going to learn about two cuddly animals, one of which you’ve definitely heard of, the other you might not have. Oh wait, you’ve heard of both animals for sure—but you might not have heard about the toys based on the animals. Thanks to Pranav and Zachary for their suggestions.

The president of the United States at the beginning of the 20th century was Theodore Roosevelt, who served from 1901 to 1909. He was sometimes called Teddy instead of Theodore, although he didn’t actually like the nickname. Roosevelt is widely considered to have been a very good president, as well as an interesting and sometimes eccentric man, but his main contribution to history as far as most people are concerned is the teddy bear.

Roosevelt was an active man who spent a lot of time horseback riding, playing tennis, hiking, swimming, boxing, and lots of other things. He also liked to read, spoke several languages, and wrote poetry—and he was an avid hunter and would travel the world to kill things. That’s what he was doing in November 1902, when the governor of Mississippi invited him on a bear hunting trip.

The hunting party killed several bears that day, but Roosevelt hadn’t shot anything. Some of the president’s attendants decided to help things along, and they chased a bear down with hounds until it was exhausted, beat it until it was almost dead, and tied it to a tree. I know, this is awful. I’m sorry. Then they said, “Hey, Mr. President, we found you a bear to shoot.”

Not only did Roosevelt refuse to kill the bear, he was angry at the people who had treated it so badly. He requested that the poor animal be shot to put it out of its misery, since by that point it was already dying from its treatment.

Because Roosevelt was the president, everything he did made its way into the newspapers, including this event. A political cartoonist used the bear hunt in a cartoon, only instead of an adult bear he made the bear a cute little cub. This inspired an inventor named Morris Michtom and his wife Rose to make a little bear cub doll to sell at their candy shop in Brooklyn, New York. They labeled it “Teddy’s bear” and the rest is history.

Most teddy bears don’t look much like an actual American black bear. The black bear lives in forested areas throughout much of North America and used to be even more widespread, but was hunted to extinction in many areas. It’s more closely related to the Asian black bear than it is to other bears found in North America, including the grizzly and polar bears. Its fur is usually black although some black bears are gray, various shades of brown, or sometimes even a rare cream color. The biggest American black bear ever measured was just barely under 8 feet long, or 2.41 meters, and probably weighed 1,100 pounds, or 500 kg. Most black bears are a lot smaller than that, though.

Black bears mate in summer but the fertilized egg cells don’t start developing until November. This gives the female plenty of time to gain lots of healthy weight before she finds a safe place to spend the winter. Black bears hibernate in cold weather, although scientists are still debating whether its metabolic changes constitute true hibernation. A bear will use a hollow tree or small cave as a den, or will dig a den. It gets comfortable in its den and soon its heart rate starts to drop until it only beats about 8 times a minute. Its body temperature stays about the same as usual and unlike many other animals that hibernate, it’s not sound asleep the whole time. It spends a lot of time awake and may even get up and move around, maybe even go out on nice days and look for food. Mostly, though, a hibernating bear doesn’t eat or drink, and it doesn’t need to defecate or urinate. Once the weather starts warming up, it emerges from its den and spends a few weeks just roaming around, eating whatever it can find while its body returns to non-hibernation status.

Babies are born during the winter, and they’re extremely small and underdeveloped at birth, only about 8 inches long on average, or 20 cm. A mother bear usually has two or three cubs, sometimes just one and occasionally four. The mother bear nurses her babies and keeps them warm through the rest of the winter, and once the weather warms up they’re big enough to come outside with her for the first time.

The American black bear is an omnivore, but it eats a lot more plant materials than it does meat. It especially likes berries and other fruit. It also eats a lot of insects, including ants, bees, and an especially nasty type of wasp called a yellow jacket. The bear has thick fur to help protect it from stings, but it also eats up the insects really fast. You can’t sting a bear if a bear just crunched you up with its big teeth. The black bear will catch fish whenever it can, will eat fawns and other baby animals when it can find them, will eat small animals like rodents when it gets the chance, will eat eggs when it comes across a nest, and will eat carrion, especially when it first emerges from hibernation.

Although black bears are dangerous, they’re also shy and avoid people when they can. The exception is when they get used to people food, either because they were given food by people, or because they found food that people left. That’s why it’s so incredibly important to never feed wild animals, especially dangerous ones like bears, and why you should learn how to properly hang your backpack from a tree when you’re camping so a bear can’t get it. If a bear learns to associate humans with food, it will become aggressive. When that happens, forest rangers have to make the hard decision to kill the bear before it hurts or kills a person.

While other species of bear growl, the American black bear doesn’t. The closest it comes to a growl is a deep call it makes in its throat, and it also makes huffing sounds, moans and grunts, squeals, clicks and pops that it makes with its mouth, including tongue clicking, and when it’s comfortable a bear may make a rumbling sound something like a hum or a purr.

This is what a black bear sounds like:

[bear sounds]

So, back to teddy bears. Plush toy bears were incredibly popular while Teddy Roosevelt was in office, but toy manufacturers were pretty sure the fad would drop in popularity once Roosevelt was no longer president. William H. Taft became president after Roosevelt, and in January 1909 he attended a banquet in Atlanta, Georgia where the main course served was possum and sweet potatoes.

These days most people don’t eat the Virginia opossum, more commonly called the possum in the United States, but it used to be considered a delicacy. Taft wolfed down an entire roast possum by himself, so fast that a doctor sitting at the table with him said he needed to slow down. Taft liked his food and he especially liked possum, and when his supporters presented him with a plush toy possum after the meal, he found it amusing.

But the people who’d given him the toy possum weren’t playing around. Ha ha, get it? Playing? Toy? They were certain their possum was going to be the next big thing. They formed a company called the Georgia Billy Possum Company and advertised the toys with the slogan, “Good-bye, Teddy Bear. Hello, Billy Possum.” They also released postcards, pins, songs and sheet music, and all sorts of other stuff branded with Billy Possum in hopes of hyping up their toy and becoming millionaires.

The problem, of course, is that while everyone cared about the poor bear that Roosevelt refused to kill, no one cared that Taft could eat a whole roast possum in one sitting. Besides, Taft was boring. Billy Possum never took off and people kept their teddy bears.

In many articles about Billy Possum, the whole idea of a possum being cute enough to make a cuddly toy from is laughed at. But possums are adorable! The Virginia opossum is a nocturnal marsupial that lives throughout much of the eastern United States, especially the southeast, and just about all of Mexico. It’s gray and white with a bare pink nose and bare pink toes, and it also has a long prehensile tail that’s mostly bare of fur that it uses to help it climb around in trees. Most possums are about the size of a cat but with much shorter legs. It’s the only marsupial that lives in North America.

The possum is omnivorous and eats fruit, carrion, eggs, nuts, vegetables, insects, and other small animals like mice and frogs. It’s resistant to the venom of snakes, bees, and scorpions, and will happily eat all three of these types of animals. It’s even less picky than the bear about what it eats and will genuinely eat pretty much anything, from birdseed and cat food it finds in people’s yards, to crayfish and baby rabbits, to ticks and persimmons, to slugs and snails.

The possum doesn’t live very long, and pretty much anything that can catch it will eat it, but it reproduces efficiently. Like other marsupials, the female has two vaginas and wombs and the male has a double penis. The female can have more than 20 babies at a time, although 8 or 9 is more common, and like other marsupials they’re born extremely early. The newborn babies are the size of a bean or a honeybee, but they’re strong enough to crawl into their mother’s pouch to find a teat. Since the possum has 13 teats, and each baby needs a teat to stay latched onto while it finishes developing, even if the mother has more than 13 babies, only 13 babies will survive.

The babies stay in their mother’s pouch for 2 1/2 months, at which point they start riding on her back instead. She carries them around for the next couple of months, teaching them how to be possums.

The possum has one real defense against predators, which it only resorts to when running away or hissing with its fur puffed up doesn’t help. It will flop onto its side with its tongue hanging out but its eyes open, and its heart rate drops and its breathing becomes shallow and slow. It also expels a stinky fluid from its anal glands. In short, it looks, acts, and smells like it’s already dead. It’s called “playing possum,” and it actually works pretty well…until the possum plays dead when threatened by a car. That’s why possums are so often killed by cars.

Many people think the possum is dirty or carries diseases, but this isn’t actually true. The possum grooms its fur and keeps it clean, and it’s actually less likely to have a disease than many other mammals. It’s even resistant to rabies, possibly because its body temperature is lower than that of most mammals and this helps keep the rabies virus from reproducing.

The Virginia opossum also has a secret that scientists only recently discovered. Its fur glows bright pink under ultraviolet light. No one is sure why.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 282: Little Longtailed Birds

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Thanks to Elaine for suggesting one of our long-tailed birds this week!

Happy birthday to Jasper!! Have a great birthday!

Further reading:

Fossil of Ancient Long-Tailed Bird Found in China

All adult scissor-tailed flycatchers have long tails:

The long-tailed sylph male is the one with the long tail:

The long-tailed widowbird male has a long tail:

The long-tailed widowbird female has a short tail:

The pin-tailed whydah male has a long tail:

A pin-tailed whydah baby (left) next to a common waxbill baby (right):

Kompsornis longicaudus had a really long tail:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week is a short episode all about little birds with really long tails. The tails are longer than the episode. Thanks to Elaine for suggesting one of the birds we talk about today!

But before we start learning about birds, we have a birthday shout-out! Happy birthday to Jasper, who has the best name and who will hopefully have the best birthday to go along with it!

Let’s start with Elaine’s suggestion, the scissor-tailed flycatcher. I’m embarrassed to admit that Elaine suggested this bird way back in 2020, so it’s about time we talked about it.

The scissor-tailed flycatcher lives in south-central North America during the summer, especially Texas and Oklahoma, and migrates to parts of Mexico and Central America in winter. It’s pale gray with black and white wings and tail, and salmon pink markings on its sides and under its wings. It also has a really long tail. It gets the name scissor-tail because its tail is so long and forked that it’s sort of the shape of an open pair of scissors. The male’s tail is typically longer than the female’s, longer than the rest of its body. The bird is about the size of an average songbird, with a body length of about 5 inches, or 13 centimeters, but with a tail that can increase its overall length to over 14 inches, or 36 cm.

The scissor-tailed flycatcher prefers open areas like pastures and fields, where there’s lots of space but some brush, trees, or fences nearby to perch in. It mostly eats insects, but it will also eat berries, especially in winter. It’s related to kingbirds and pewees and will even hybridize with the western kingbird where their ranges overlap. Its long tail is partly for display, but mostly it helps the bird maneuver in midair as it chases insects, or hover in midair as it looks around for an insect to catch. It especially likes grasshoppers, and when it catches one, it will usually kill it before eating it by smashing it against a tree limb or other perch.

Another little bird with a long tail is the long-tailed sylph, which is a type of hummingbird! It lives on the eastern slopes of the Andes Mountains in northwestern South America, mostly along forest edges, in gardens, grasslands, and other mostly open areas. It migrates to different parts of the mountains at different times of year to follow the flowering of its favorite plants. It’s larger than many species of hummingbird even if you don’t count the tail.

It eats nectar like other hummingbirds do, but also eats tiny insects and spiders. Its bill is black and not very long compared to most of its relations. Sometimes it will jab the tip of its bill straight through the base of a flower to get at the nectar, instead of inserting it into the flower like other hummingbirds do, and while it can hover, sometimes it perches to feed instead.

Both the male and female long-tailed sylph are a beautiful metallic blue and green in color, although the male is brighter and has purplish-brown wings. The female is about 4 inches long, or 10 cm, including her tail, and while the male is about the same size as the female, his tail is really long—up to 4.5 inches long, or 12 cm. His tail is forked like the scissor-tailed flycatcher’s, but unlike the flycatcher, the sylph’s tail makes it harder for the bird to fly. During breeding season the male attracts a mate by flying in a U-shaped pattern that shows off his tail and his flying ability.

The male long-tailed widowbird also attracts a mate with a flying display to show off his long tail. It lives in grasslands in a few parts of Africa, with the biggest population in South Africa. It forages in small flocks looking for seeds, and it also eats the occasional insect or spider. It’s a sparrow-like bird only about 4 inches long, or 10 cm, not counting its tail. The female is mostly brown with darker streaks and has a short tail. The male is black with red and white patches on the shoulders of his wings, called epaulets. His coloring, including the epaulets, is almost identical to that of a totally unrelated bird, the red-winged blackbird of North America, but he has something the blackbird doesn’t: a gigantically long tail.

The male widowbird’s tail is made up of twelve feathers, and about half of them grow up to 20 inches long. That’s nearly two feet long, or half a meter. Like the long-tailed sylph, the long-tailed widowbird’s tail actually makes it harder for him to fly. If it’s raining, he can’t fly at all. Fortunately for him, outside of the breeding season his tail is much shorter. During display flights, he spreads his tail feathers to show them off better and flies very slowly. Males with the longest tails attract the most females.

Similarly, the pin-tailed whydah is another little sparrow-like bird where the male grows a really long tail to attract females. It lives in grasslands, savannas, and open woodlands in sub-Saharan Africa, which just means south of the Sahara Desert. It mostly eats seeds.

During breeding season, the male is a striking pattern of black and white with a bright orangey-red bill and really long tail plumes. He’s about the size of the long-tailed widowbird but his tail grows about 8 inches long, or 20 cm. The female is brown with darker streaks and looks a lot like a sparrow, although it’s not related to sparrows. To impress a female, the pin-tailed whydah will hover in place near her, showing off his long tail plumes and his flying ability.

A lot of whydah species grow long tails. A lot of whydahs are also brood parasites, including this one, meaning that instead of building a nest and taking care of her own eggs, the female sneaks in and lays her eggs in the nest of a different species of bird. Then she flies away, probably whistling to make her seem extra nonchalant, and leaves the other bird to take care of her eggs and the babies when they hatch. She mostly lays her eggs in the nests of various species of finch, and not only do her eggs resemble the finch’s eggs except that they’re bigger, the babies resemble finch babies when they hatch, except they’re bigger.

Specifically, the babies have a really specific gape pattern. When an adult bird approaches its nest, a baby bird will gape its mouth wide to beg for food. This prompts the parent bird to shove some food down into that mouth. The more likely a baby is to be noticed by its parent, the more likely it is to get extra food, so natural selection favors babies with striking patterns and bright colors inside their mouths. Many finches, especially ones called waxbills, have a specific pattern of black and white dots in their mouths that pretty much acts as a food runway. Insert food here. The whydah’s mouth gape pattern mimics the waxbill’s almost exactly. But as I said, the whydah chick is bigger, which means it can push the finch babies out of the way and end up with more food.

The pin-tailed whydah is a common bird and easily tamed, so people sometimes keep it as a pet. This is a problem when it’s brought to places where it isn’t a native bird, because it sometimes escapes or is set free by its owners. If enough of the birds are released in one area, they can become invasive species. This has happened with the pin-tailed whydah in many parts of the world, including parts of Portugal, Singapore, Puerto Rico, and most recently southern California. Since they’re brood parasites, they can negatively impact a lot of other bird species in a very short time. But a study released in 2020 about the California population found that they mostly parasitize the nests of a bird called the scaly-breasted munia, a species of waxbill from southern Asia that’s been introduced to other places, including southern California, where it’s also an invasive species. So I guess it could be worse.

There are lots of other birds with long tails we could talk about, way too many to fit into one episode, but let’s finish with an extinct bird, since that seems to be the theme lately. In May 2020, an ancient bird was described as Kompsornis longicaudus, and it lived 120 million years ago in what is now China. Its name means long-tailed elegant bird. It was bigger than the other birds we’ve talked about today, a little over two feet long, or 70 cm, but a lot of that length was tail.

Kompsornis is only known from a single fossil, but that fossil is amazing. Not only is it almost a complete skeleton, it’s articulated, meaning it was preserved with all the body parts together as they were in life, instead of the bones being jumbled up. That means we know a lot about it, including the fact that unlike other birds of the time, it didn’t appear to have any teeth. It also shows other features seen in modern birds but not always found in ancient birds, including a pronounced keel, which is where wing muscles attach. That indicates it was probably a strong flier. It also had a really long tail, but unlike modern birds its tail was bony like a lizard’s tail although it was covered with feathers.

During their study of Kompsornis, the research team compared it to other birds in the order Jeholornithiformes, which seem to be its closest relations. There were six species known, with Kompsornis making a seventh—except that during the study, the team discovered that one species was a fake! Dalianraptor was also only known from one fossil, and that fossil was of a different bird with the arms of a flightless theropod added in place of its missing wings. Send that fossil to fossil jail!

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 280: Lesser-Known Sharks

Thanks to Tobey and Janice this week for their suggestions of lesser-known sharks!

Further reading/watching:

CREATURE FEATURE: The Spinner Shark [this site has a great video of spinner sharks spinning up out of the water!]

Acanthorhachis, a new genus of shark from the Carboniferous (Westfalian) of Yorkshire, England

150 Year Old Fossil Mystery Solved [note: it is not actually solved]

The cartoon-eyed spurdog shark:

The spinner shark spinning out of the water:

The spinner shark not spinning (photo by Andy Murch):

A Listracanthus spine:

Show transcript:

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

This week we’re going to learn about three sharks you may have never heard of before! The first was suggested by my aunt Janice and the second by listener Tobey. The third is a mystery from the fossil record.

You may have heard about the findings of a study published in November of 2021, with headlines like “Venomous sharks invade the Thames!” My aunt Janice sent me a link to an article like this. Nobody is invading anything, though. The sharks belong where they are. It was their absence for decades that was a problem, and the study discovered that they’re back.

The Thames is a big river in southern England that empties into the North Sea near London. Because it flows through such a huge city, it’s pretty badly polluted despite attempts in the last few decades to clean it up. It was so polluted by the 1950s, in fact, that it was declared biologically dead. But after a lot of effort by conservationists, fish and other animals have moved back into the river and lots of birds now visit it too. It also doesn’t smell as bad as it used to. One of the fish now found again in the Thames is a small shark called the spurdog, or spiny dogfish.

The spurdog lives in many parts of the world, mostly in shallow water just off the coast, although it’s been found in deep water too. A big female can grow almost three feet long, or 85 cm, while males are smaller. It’s a bottom dweller that eats whatever animals it finds on the sea floor, including crabs, sea cucumbers, and shrimp, and it will also eat jellyfish, squid, and fish when it can catch them. It’s even been known to hunt in packs.

It’s gray-brown in color with little white spots, and it has large eyes that kind of look like the eyes of a cartoon shark. It also has a spine in front of each of its two dorsal fins, which can inject venom into potential predators. The venom isn’t deadly to humans but would definitely hurt, so please don’t try to pet a spurdog shark. If the shark feels threatened, it curls its body around into a sort of shark donut shape, which allows it to jab its spines into whatever is trying to grab it.

The spurdog used to be really common, and was an important food for many people. But so many of them were and are caught to be ground into fertilizer or used in pet food that they’re now considered vulnerable worldwide and critically endangered around Europe, where their numbers have dropped by 95% in the last few decades. It’s now a protected species in many areas.

The female spurdog retains her fertilized eggs in her body like a lot of sharks do. The eggs hatch inside her and the babies develop further before she gives birth to them and they swim off on their own. It takes up to two years before a pup is ready to be born, and females don’t reach maturity until they’re around 16 years old, so it’s going to take a long time for the species to bounce back from nearly being wiped out. Fortunately, the spurdog can live almost 70 years and possibly longer, if it’s not killed and ground up to fertilize someone’s lawn. The sharks like to give birth in shallow water around the mouths of rivers, where the water is well oxygenated and there’s lots of small food for their babies to eat, which is why they’ve moved back into the Thames.

Next, Tobey suggested we talk about the spinner shark. It’s much bigger than the spurdog, sometimes growing as much as 10 feet long, or 3 meters. It lives in warm, shallow coastal water throughout much of the world. It has a pointy snout and is brown-gray with black tips on its tail and fins, and in fact it looks so much like the blacktip shark that it can be hard to tell the two species apart unless you get a really good look. It and the blacktip shark also share a unique feeding strategy that gives the spinner shark its name.

The shark eats a lot of fish, especially small fish that live in schools. When the spinner shark comes across a school of fish, it swims beneath it, then upward quickly through the school. As it swims it spins around and around like an American football, but unlike a football it bites and swallows fish as it goes. It can move so fast that it often shoots right out of the water, still spinning, up to 20 feet, or 6 meters, before falling back into the ocean. The blacktip shark sometimes does this too, but the spinner shark is an expert at this maneuver.

There’s a link in the show notes to a page where you can watch a video of spinner sharks spinning out of the water and flopping back down. It’s amazing and hilarious. Tobey mentioned that the spinner shark is an acrobatic shark, and it certainly is! It’s like a ballet dancer or figure skater, but with a lot more teeth. And fewer legs.

Because spinner sharks mainly eat fish, along with cephalopods, they almost never attack humans because they don’t consider humans to be food. Humans consider the spinner shark food, though, and they’re listed as vulnerable due to overhunting and habitat loss.

We’ll finish with a mystery shark. I’ve had Listracanthus on my ideas list for a couple of years, hoping that new information would come to light, but let’s go ahead and talk about it now. It’s too awesome to wait any longer.

We know very little about Listracanthus even though it was around for at least 75 million years, since it’s an early shark or shark relative with a cartilaginous skeleton. Cartilage doesn’t fossilize very well compared to bone, so we don’t have much of an idea of what the shark looked like. What we do have are spines that grew all over the fish and that probably made it look like it was covered with bristles or even weird feathers. The spines are a type of denticle that could be up to 4 inches long, or 10 cm. They weren’t just spines, though. They were spines that had smaller spines growing from their sides, sort of like a feather has a main shaft with smaller shafts growing from the sides.

The spines are fairly common in the fossil record from parts of North America, dating from about 326 million years ago to about 251 million years ago. Listracanthus was closely related to another spiny shark-like fish, Acanthorhachis, whose spines have been found in parts of Europe and who lived around 310 million years ago, but whose spines are less than 3 inches long at most, or 7 cm.

Some researchers think the spines were only present on parts of the shark, maybe just the head or down the back, but others think the sharks were covered with the spines. Many times, lots and lots of the spines are found together and probably belong to a single individual whose body didn’t fossilize, only its spines. Some researchers even think that the flattened denticles from a shark or shark relation called Petrodus, which is found in the same areas at the same times as Listracanthus, might actually be Listracanthus belly denticles.

The spines probably pointed backwards toward the tail, which would reduce drag as the fish swam, and they might have been for display or for protection from predators, or of course both. The main parts of the spine were also hollow and there’s evidence there were capillaries inside, so they might have had a chemosensory or electrosensory function too.

Modern sharks have denticles that make their skin rough, sort of like sandpaper. One modern shark, the sandy dogfish, Scyliorhinus canicula, which is common in shallow water off the coasts of western Europe and northern Africa, and in the Mediterranean, has especially rough denticles on its tail. They aren’t precisely spines, but they’re more than just little rough patches. The sandy dogfish is a small, slender shark that barely grows more than about three feet long, or about a meter, and it eats anything it can catch. Young dogfish especially like small crustaceans, and sometimes they catch an animal that’s too big to swallow whole. In that case, the shark sticks the animal on the denticles near its tail, which anchors it in place so it can tear bite-sized pieces off. Some other sharks do this too, so it’s possible that Listracanthus and its relations may have used its spines for similar behavior.

We don’t know much about these sharks because all we have are their spines. Only one probable specimen has been found, by a paleontologist named Rainer Zangerl. Dr. Zangerl found the remains of an eel-like shark in Indiana that was covered in spines, but unfortunately as the rock dried out after being uncovered, the fossil literally disintegrated into dust.

In August of 2019, a fossil hunter posted on an online forum for fossil enthusiasts to say he’d found a Listracanthus specimen. He posted pictures, although since the fossil hasn’t been prepared it isn’t much to look at. It’s just an undulating bump down a piece of shale that kind of looks like a dead snake. Fortunately, the man in question, who goes by RCFossils, knew instantly what he’d found. He also knew better than to try to clean it up himself. Instead, he’s been working on trying to find a professional interested in taking the project on. In May of 2022 he posted again to say he’d managed to get an X-ray of the fossil, which shows a backbone but no sign of a skull. He’s having trouble finding anyone who has the time and interest in studying the fossil, but hopefully he’ll find someone soon and we’ll all learn more about this mysterious pointy shark.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 279: Mean Piggies

Thanks to Molly for suggesting andrewsarchus and entelodont, our mean “piggies” we learn about this week!

Further reading:

Andrewsarchus, “Superb Skull of a Gigantic Beast”

Dark Folklore by Mark Norman and Tracey Norman

Further listening:

The Folklore Podcast

Andrewsarchus (taken from article linked above):

Andrewsarchus’s skull. I’m not sure who the guy holding it is, but I like to think his name is Andrew:

Entelodont:

Show transcript:

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

I’m getting really backed up on listener suggestions, so over the next few months I plan to cover as many of them as possible. We’ll start with two suggestions by Molly, who wanted to learn about Andrewsarchus and the related Entelodont. We talked about entelodonts briefly back in episode 116, and if you remember that episode, you may remember that entelodonts are sometimes referred to as the terminator pig or the hell pig. So yes, we are going to learn about some mean piggies this week, with a bonus fun mystery piggy at the end.

Andrewsarchus mongoliensis lived in what is now central Asia about 42 million years ago. It’s only known from a single skull found in 1923 in Inner Mongolia, which is part of China these days. The skull has a long snout and is big and wide, over 2.5 feet long, or 83 cm. It has huge, strong teeth that look ferocious.

When the skull was first found, some paleontologists on the team thought it was from a huge wolf-like carnivore. But others weren’t so sure. They thought it was the skull of a pig relative, and pigs are omnivores. Without more fossil remains, we can’t know for sure what Andrewsarchus’s body looked like, but these days scientists mostly think it was closely related to entelodonts.

Despite being called the terminator pig, entelodonts weren’t very closely related to pigs, although they and Andrewsarchus are in the order Artiodactyla. That’s the order that includes all even-toed hoofed mammals and their close relations, including pigs, but also including hippos and whales. Hippos and whales are actually pretty closely related, and entelodonts and Andrewsarchus were more closely related to hippos than to pigs.

Daeodon [DIE-oh-don] was the biggest entelodont known, and it may have stood up to 7 feet tall at the shoulder, or just over 2 meters. It lived in North America, but there was another species from Eurasia, Paraentelodon intermedium, that was probably close to the same size. Both lived about 22 million years ago.

Entelodonts had big, wide skulls with flared cheekbones and knob-like bony protrusions, so its head may have looked something like a warthog’s head. It also had cloven hooves. We don’t know if Andrewsarchus had hooves since we haven’t found anything but that one huge skull. The larger species of Entelodont had a humped shoulder something like a bison for the attachment of strong neck muscles to support the head’s weight, and Andrewsarchus probably had this too. The rest of the body was much more lightly built, with short, slender legs and a skinny little tail.

Even though Entelodont teeth are fearsome-looking, and at least some species of Entelodont were probably active hunters, they’re considered omnivores and Andrewsarchus probably was too. In fact, because Andrewsarchus was found on what was once a beach along the ocean, some researchers think it might have used its big forward-pointing front teeth to dig shellfish out of the sand. Most likely it ate pretty much anything it could find or catch, including shellfish, turtles, and other small animals, carrion, and plant material like fruit, nuts, and roots.

The teeth of some entelodont species show wear marks that indicate it probably bit through bones pretty frequently, possibly while scavenging already dead animals but possibly also when killing prey. One fossil skull of a herbivorous artiodactyl that lived in North America was found with an entelodont incisor embedded in it.

On the other hand, we have a set of fossil tracks in Nebraska, in the United States, that shows the behavior of what may have been an entelodont called Archaeotherium. Archaeotherium lived around 30 million years ago and grew up to 5 feet tall at the shoulder, or 1.5 meters, although most specimens found were closer to 4 feet tall, or 1.2 meters. The fossil tracks are from three animals: a type of rhinoceros, a predator of some kind, possibly the hyena-like Hyaenodon, and a species of Archaeotherium. The rhinoceros tracks show that it was walking along, then suddenly took off at a run. The Hyaenodon tracks are nearby and possibly indicate pursuit of the rhino, or it might have just happened to be nearby and frightened the rhino. The Archaeotherium tracks, meanwhile, zigzag back and forth. What on earth is going on with that?

Entelodonts had a very good sense of smell, much like pigs do, and walking in a zigzag pattern would allow Archaeotherium to smell things more efficiently. Some researchers suggest it might have been keeping an eye on the rhino hunt, and that if the Hyaenodon managed to bring down its prey, Archaeotherium might have decided to chase Hyaenodon away from its kill. It might also have been waiting for one or both animals to become tired, and then it could attack. Then again, it might just have been looking for some yummy fruit to eat. While some places online will tell you Archaeotherium was hunting the rhino, that’s not what the tracks indicate.

Entelodonts could open their mouths really, really wide. If you’ve ever seen a hippo with its humongous mouth open, that’s what we’re talking about here. Male hippos sometimes fight by jaw-wrestling each other, and researchers think entelodonts might have done something similar. A lot of entelodont skulls show healed puncture wounds in places consistent with jaw-wrestling. The knobby protrusions on its skull might have been an adaptation to this behavior, with thickened skin over them to keep a rival’s teeth from biting too deeply. This is the case with some pigs with similar skull protrusions, which we talked about in episode 128. The head bite wounds are only seen in adult animals, and younger animals didn’t have the massive cheek and jaw muscles seen in adults.

The big question is whether Andrewsarchus was actually an entelodont or just closely related to the entelodonts. That’s the same thing paleontologists have been discussing for the last century. Until we find more Andrewsarchus fossils, though, there’s only so much we can determine about the animal, including how similar it was to the entelodonts. For instance, while entelodonts did have cloven hooves, the two halves of the hoof could spread apart like fingers, which is similar to the way camel feet are structured. This would have helped it walk on soft ground, like sand or mud. If Andrewsarchus turns out to have similar feet, it was probably an entelodont.

Finding more Andrewsarchus remains will allow us to get a good idea of how big it could grow, too. Estimates based on the same proportions seen in entelodonts suggest it might have stood about 6 feet tall at the shoulder, or 1.8 meters.

As we’ve established, entelodonts and Andrewsarchus weren’t actually pigs, although they probably looked a lot like weird oversized warthogs with some features seen in wild boars. There’s no evidence they had a pig-like snout, called a nasal disk, which is flattened at the end. Entelodonts had nostrils on the sides of the snout, something like a horse’s nostrils.

But let’s finish with an actual pig, the mystery of the sewer pig. I got this information from a fantastic book called Dark Folklore by Mark and Tracey Norman, and I read the book because I listen to The Folklore Podcast, which is by folklorist Mark Norman, although I think Tracey Norman helps out with it too. I’ll just quote from the book, and definitely check the show notes for a link if you want to order your own copy.

“Foreshadowing the 1980s panic about baby alligators being taken home as pets and subsequently flushed down the toilet into the sewer system of New York, 1859 London was overtaken by a panic about the Sewer Pigs of Hampstead.

“The sewer pigs were thought to be a monstrous porcine family living entirely below ground in the London sewer system, and even featured in the Daily Telegraph newspaper. A sow had apparently become trapped, it was said, and had given birth to a litter of piglets, the entire family living off the rubbish that accumulated in the sewers and producing litter after litter. The population lived in fear of these terrible creatures escaping from the sewer system and running riot throughout London.

“Obviously, there is nothing within a sewer system that would sustain a pig, let alone a number of them. The fear connected to this particular urban legend is disease and it arose after the hot summer of 1858 caused a devastating outbreak of typhoid and cholera in the city. Unsurprisingly, there has never been any evidence of pigs in London’s sewers, monstrous, lost or otherwise.”

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 275: The Axolotl, the Hellbender, and Friends

This week it’s Zoe and Dillon’s episode! They wanted to learn about some really interesting salamanders, including the axolotl and the hellbender!

A big birthday shout-out to Heather R. too. The very happiest of birthdays to you!

Further reading:

Mexico City’s endangered axolotl has found fame—is that enough to save it?

How Do Salamanders Breathe?

Most wild axolotls are brown:

Most captive-bred axolotls are leucistic:

The hellbender doesn’t have external gills as an adult:

The red eft, the juvenile stage of the red-spotted newt:

Adult mudpuppies have external gills just like axolotls do:

Show transcript:

Welcome to Strange Animals Podcast. We’re your cohosts, Zoe and Dillon. And I’m your third cohost, Kate Shaw.

This week we have Zoe and Dillon’s episode, and they want to learn about the axolotl, the hellbender, and some other salamanders. It’ll be the greatest amphibian episode ever!

But first, we have a birthday shout-out! Happy birthday to Heather R.! I hope the weather is perfect for your birthday and you get to go out and appreciate it.

So, let’s start with the axolotl, because everyone loves it! “Axolotl” isn’t the way it’s pronounced in its native country of Mexico, since it comes from the name of an Aztec god of fire and lightning, but it’s the common pronunciation in English so I’m going to stick with that one. In addition to Zoe and Dillon, at least one other listener has suggested we cover the axolotl. That would be Rosy, and I apologize to anyone else who suggested it but whose name didn’t make it onto the suggestions list.

Way back in episode 104, about tiger salamanders, we learned that the tiger salamander is closely related to the axolotl. But the two species look very different most of the time because the axolotl exhibits a trait called neoteny. In most salamanders, the egg hatches into a larval salamander that lives in water, which means it has external gills so it can breathe underwater. It grows and ultimately metamorphoses into a juvenile salamander that spends most of its time on land, so it loses its external gills in the metamorphosis. Eventually it takes on its adult coloration and pattern. But the axolotl doesn’t metamorphose. Even when it matures, it still looks kind of like a big larva, complete with external gills, and it lives underwater its whole life.

Very rarely, an axolotl metamorphoses into an adult form, at which point it looks a whole lot like a tiger salamander. This generally happens if the individual is exposed to excess iodine in its diet, and metamorphosing like this may actually lead to the axolotl’s death. Axolotls exhibit neoteny because it gives them an advantage in their natural range, so even though it seems strange to us compared to all those other salamanders, it’s what the axolotl is supposed to do.

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

Also if you’ve only ever seen pictures of axolotls you may think they’re all white or pink. That’s actually rare in the wild. Most wild axolotls are brown, greenish-brown, or gray, often with lighter speckles. They can even change color somewhat to blend in with their surroundings better.

It’s captive axolotls that are so often white or pink, or sometimes other colors or patterns. That’s because they’re bred for the pet trade and for medical research, because not only are they cute and relatively easy to keep in captivity, they have some amazing abilities. Their ability to regenerate lost and injured body parts is remarkable even for amphibians, but, interestingly, axolotls that have been induced to metamorphose have much less regeneration ability. Researchers study axolotls to learn more about how regeneration works, how vertebrates evolved various aspects of anatomy, how genetics of coloration work, and much more. They’re so common in laboratory studies that you’d think there’s no way they could be endangered—but they are. Some conservationists think there may be as few as 50 individuals left in the wild.

The main problem is habitat loss. One lake where the axolotl was once found is completely gone, drained to control flooding and provide more land for people to use. The other lake isn’t so much a lake anymore as a series of canals in Mexico City, and they’re polluted and home to introduced species of fish that eat axolotl eggs. Even though part of their range was designated as a nature reserve in 1993, that hasn’t done much to stop the pollutants or invasive fish.

Not only that, the captive-bred axolotls are so different from their wild cousins that some people think they should be considered a different species. You couldn’t take a pet axolotl and dump it into a lake and expect it to live. Conservation efforts in Mexico are focusing on a captive breeding program of axolotls caught in the wild. Since the salamander’s native range isn’t healthy right now, the group is trying to establish temporary homes in university ponds prepared just for that purpose. So far the project is a success.

At the same time, conservationists and just regular people who like axolotls are working hard to get its native habitat cleaned up. This includes educating people about the axolotl, and helping people set up small farms that use traditional methods that don’t require fertilizer or insecticides that run off into the water. These farms are called chinampas and are made up of artificial islands with canals around them. The islands actually help filter pollutants from the surrounding water, and the canals are ideal for axolotls to live in. The farmers also install screens with filters to keep invasive fish out and clean up the water even more, and some of the captive-bred wild axolotls have been introduced to these canals successfully.

Even though the axolotl has external gills to collect oxygen from the water, it has lungs too. It will sometimes gulp air from the surface, but most of the time it gets all the oxygen it needs from its gills. It eats small animals like worms, insects, and even small fish, but while it does have tiny teeth, they’re actually vestigial. The axolotl doesn’t chew its food but instead sucks its prey whole right down into its stomach.

We talked about the hellbender briefly in episode 14, but that was five years ago. In fact, it was exactly five years ago. Episode 14 was released on May 8, 2017, and this episode is being released on May 9, 2022. I swear I did not plan it that way but it’s pretty neat.

The hellbender has a restricted range too, although it’s not as restricted as the axolotl’s. It lives in parts of the eastern United States, especially in the Appalachian Mountains and the Ozarks. It can grow nearly 30 inches long, or 74 cm, and is heavy for its size, up to 5.5 lbs, or 2.5 kg. This is the fifth heaviest amphibian alive today in the whole world! It needs clean, shallow, fast-moving streams with lots of rocks, because it spends almost all its life in the water hiding among rocks. But the rocks are important for another reason too. As water rushes over and around rocks, it splashes around and absorbs more oxygen. Well-oxygenated water helps the hellbender breathe, which is even more complicated than it sounds.

Like other salamanders, the hellbender hatches from eggs laid in the water and at first are just big tadpoles with external gills. They metamorphose in stages until they’re full grown at almost two years old, at which point they lose their gills, although they may retain a nonfunctioning gill slit. The adult hellbender has large lungs, but it doesn’t use them for breathing. They’re just for buoyancy. The hellbender absorbs oxygen from the water through its skin, which is why it needs well-oxygenated water flowing quickly across it all the time. To increase its surface area and help it absorb that much more oxygen, its skin is loose and has folds along the sides.

The hellbender is flattened in shape, which helps it hide under rocks and helps keep it from being swept away by currents when it’s moving around in the water. It’s brown with black speckles on its back. It mostly eats crawdads, also called crayfish, but it will eat small fish and amphibians, tadpoles, the eggs of frogs and fish, and in fact it will also eat the eggs of other hellbenders. Occasionally a hellbender will eat a smaller hellbender too. It’s a solitary animal except during breeding season, and even then, once the female has laid her eggs in a nest the male makes and the male fertilizes them, the pair don’t spend any time together. The male actually chases the female away. Then he spends the next few months guarding the eggs and making sure they get enough oxygen by waving his tail and skin folds over them.

The hellbender doesn’t have very good eyesight, although it has a good sense of smell. It’s very territorial and seldom leaves the small stretch of water where it lives and hunts. Very occasionally it will leave the water and walk around on land. Most of the time it walks around underwater, though, instead of swimming. Its toes have rough pads that help it walk even on slippery rocks. During the day, though, it usually hides under its home rock. Its skin contains light-sensitive cells, which are mostly concentrated in its tail. This means that it can actually sense how much light is shining on its body even if its head is hidden under a rock. The reason its tail has more light-sensing cells is because its tail is more likely to be sticking out from under its rock. Since a lot of animals eat the hellbender, it needs to be fully hidden by its rock during the day.

Some people think the hellbender is poisonous or venomous, but it’s actually completely harmless unless you are a very small aquatic animal.

Because salamanders, like other amphibians, have to keep their skin moist, they’re vulnerable to water pollution. Any pollutants in the water are liable to be absorbed into the salamander’s body, which can make it sick. Habitat loss, disease, and invasive species are also major causes of declines in salamander species.

Salamanders have been around for at least 180 million years. Amphibians in general probably developed from lobe-finned fish around 360 million years ago. A study published in 2020 examined 3D scans of skulls from 148 species of salamander to compare minute differences and learn more about how they evolved. Animals that undergo metamorphosis, including salamanders, have very different skulls from animals that don’t, since different parts of the skull develop in stages independently of other parts. The study found that while salamanders have always been metamorphic, different life cycles have evolved separately at least eleven times.

One of the things Zoe asked in particular was whether salamanders actually breathe through their nostrils. It depends on the species. Salamanders are definitely complicated when it comes to breathing. Like many amphibians, the salamander doesn’t have special muscles to move air in and out of its lungs the way mammals do. Instead, it moves air in and out by gular pumping, also called buccal pumping.

A salamander lowers the floor of its mouth, expanding the throat, which pulls air into the throat by way of the nostrils. Then the salamander closes its nostrils and raises the floor of its throat. This causes the air to enter the lungs. It does the same process in reverse to breathe out. That’s why salamanders and other amphibians appear to be gulping all the time. That’s how they breathe.

Complicated as this sounds, the salamander doesn’t have to concentrate to do it any more than we have to concentrate to breathe. Also, even if it mostly gets oxygen through its lungs, all salamanders appear to be able to absorb a certain amount of oxygen through the skin too.

Zoe and Dillon were especially interested in salamanders that live in their part of the world, which is the state of Pennsylvania in the eastern United States. In addition to the hellbender, there are several dozen salamander species known from Pennsylvania, and probably quite a few that haven’t been discovered yet. This includes the red-spotted newt, which lives in forests in muddy or wet areas. It grows up to about 5 inches long, or 13 cm, and eats insects, worms, frog eggs and tadpoles, and other small animals.

As an adult, the red-spotted newt is greenish-brown, often with a row of red spots outlined with black along its sides and tiny black dots all over, and a yellow or orange belly. The adult mostly lives in the water, but during the juvenile stage it mostly lives on land and can travel widely, especially after rain. It also looks very different during the juvenile stage, with a bright orangey-red body and spots outlined with black, which is why it’s often called a red eft. An eft is a juvenile salamander. The bright red coloring may tell you not to eat the red eft, because it’s poisonous! Its skin contains toxins that make it taste bad and can make a potential predator sick.

Another salamander common throughout Pennsylvania is the spotted salamander, which can grow almost 10 inches long, or 24 cm. It’s a big, strong salamander that’s black or gray with big yellow or orangey spots all over. As a juvenile it looks very similar, although smaller, but with tiny spots or no spots.

Finally, to wrap around to where we started, another large species of salamander that lives in parts of western Pennsylvania, and other nearby areas, is the mudpuppy. It looks a lot like a juvenile hellbender but isn’t as big, with the largest measured adult growing just over 17 inches long, or almost 44 cm. Like the axolotl, the mudpuppy exhibits neoteny. It lives in lakes, ponds, and streams and retains its gills throughout its life. Its gills are large and reddish in color. If a mudpuppy lives in your pond or backyard stream, you can be sure the water is clean because its gills are very sensitive to pollutants.

The mudpuppy spends most of its time under rocks and walking along the bottom of the lakebed or streambed, looking for food. It’s gray, black, or reddish-brown, sometimes with speckles or spots. It has a lot of tiny teeth where you’d expect to find teeth, and more teeth on the roof of its mouth where you would not typically expect to find teeth. It needs all these teeth because it eats slippery food like small fish, worms, and frogs, along with insects and other small animals.

Even though the mudpuppy has all those teeth, it’s harmless to humans and just wants to be left alone, but that’s pretty much the case for all salamanders. And some people.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 273: Noisy Invertebrates

Thanks to Isaac, Joel, Ethan, and Richard E. for their suggestions this week!

Don’t forget to check out our crowdfunding campaign for some cute enamel pins!

Further reading:

Snapping Shrimp Drown Out Sonar with Bubble-Popping Trick

One example of a pistol shrimp–there are many, many species (photo from this site):

A walnut sphinx moth sitting on someone’s hand (photo by John Lindsey, found on this page):

A caterpillar (photo by Ashley Bosarge, found on this page):

The Asian longhorned beetle (from this site):

The white-spotted sawyer pine beetle is another type of longhorned beetle:

Show transcript:

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

It’s been too long since we’ve had an invertebrates episode, so this week let’s learn about some invertebrates that make noise. Thanks to Isaac, Joel, Ethan, and Richard E. for their suggestions!

We don’t have a birthday shout-out this week, but we do have a reminder that the next five episodes, the ones releasing in May, are our Kickstarter episodes! Those are from the Kickstarter level where the backer got to choose the topic and work with me to craft the episode. I’ve been amazed at how fantastic those episodes turned out, and I think you’ll like them.

Speaking of crowdfunding campaigns, a quick reminder that the Tiny Pin Friends Indiegogo is still going on. It’s sort of stuck halfway to our goal, probably because I got busy with the book release and haven’t been telling people about the pins, so if you want to take a look at the pin designs, there’s a link in the show notes. Thanks!

Now, on to the invertebrates! Both Isaac and Joel suggested the same topic at different times, pistol shrimp. This is a group of shrimps also called snapping shrimps. Most species live in warm, shallow coastal habitats like coral reefs, but some live in colder water and at least one lives in freshwater caves.

The pistol shrimp only grows a few inches long at most, or about 5 cm. It gets its name from its big claw, which functions in a similar way to the workings of a pistol (sort of). But instead of shooting bullets, the claw shoots bubbles—but so incredibly fast, they might as well be bullets.

A pistol shrimp has two claws, but one is small and used for picking stuff up and grabbing food. The other claw is the pistol claw that’s much bigger and stronger. Which claw is which depends on the individual, and if a shrimp’s pistol claw gets damaged or bitten off, its other claw will develop into a pistol claw. The damaged or lost claw eventually regenerates into a little claw for manipulating food.

The pistol shrimp is mostly an ambush hunter. It will hide in a burrow or rock crevice with its antennae sticking out, and when a small animal like a fish happens by, the shrimp will emerge from its hiding place just far enough to get a good shot at the animal. It opens its big claw and snaps it shut so fast and so forcefully that it shoots tiny bubbles out at speeds of over 60mph, or 100 km/hour. Obviously the bubbles don’t travel very far at that speed, really only a few millimeters, but it’s powerful enough at this short range to stun or outright kill a small animal. The shrimp then grabs its stunned or dead prey and drags it back into its hiding spot to eat.

The process is way more complicated than it sounds. When the claw opens, water rushes into a tiny chamber in the claw. When it snaps closed, a tiny point on the claw pushes into the chamber, which leaves no room for the water. The water is therefore forced out of the chamber at such incredibly high pressure that it leaves vapor-filled cavities in the water, the bubbles, which collapse with a loud snapping sound. The pressure wave from the collapsing bubble is what actually kills or stuns an animal. Physics! I don’t understand it! Check the show notes for an article that goes into more detail about this process, which I’ve hopefully described correctly.

The bubble’s collapse makes such a loud noise that the pistol shrimp is one of the loudest animals in the ocean, but the sound lasts for less than a millisecond. It takes 100 to 400 milliseconds for you to blink your eye, to give you a comparison. The collapsing bubble also produces light and intense heat, but it’s such a tiny bubble with such a limited range that the heat and light don’t make any difference. The light isn’t very bright and lasts such a tiny amount of time that the human eye can’t even perceive it.

The pistol shrimp doesn’t only use its big claw to hunt for food and defend itself from potential predators. It also communicates with other pistol shrimp with the sound, and pistol shrimp can live in colonies of hundreds of individuals. With them all snapping together, no matter how short each snap is, the collective sound can be incredibly loud—so loud it interferes with sonar in submarines.

This is what it sounds like, although it also kind of sounds like popcorn popping, if you ask me:

[snapping shrimp sounds]

Next, Ethan suggested the walnut sphinx moth, because his son found one, they looked it up, and they were both amazed at how awesome it is. It lives in the eastern part of North America and is a big, robust moth with a wingspan up to 3 inches across, or 7.5 cm. Its wings and body are mostly brown and gray, often with darker and lighter markings but sometimes all one color. The edges of its wings have an uneven scallop shape and when it perches, it spreads both pairs of wings out in a sort of X shape. Its wing shape and coloring make it look a lot like an old dead leaf.

Like many moths, the walnut sphinx moth doesn’t eat at all as an adult. After it metamorphoses into an adult, it only lives long enough to mate and lay eggs. It spends most of its life as a caterpillar, where it eats the leaves of various kinds of trees, especially nut trees, including walnut, hazelnut, and hickory. The caterpillar is a pretty green with tiny white dots all over and yellow or white streaks along its sides, although some individuals are red, orange, or pink instead of green. It has a red or green horn on its tail end.

The most amazing thing about this moth is how the caterpillar keeps from being eaten. Lots of animals like to eat caterpillars, especially birds, but when a bird tries to grab this caterpillar, it thrashes around and actually makes a sound! You don’t typically think of caterpillars as noisy. It’s actually not very loud, but it does make a little whistle that mimics a bird’s alarm call, and can make a little buzzing sound too. The caterpillar makes the sound through its breathing tubes, called spiracles.

Researchers have played the caterpillar’s whistle sound at bird feeders and the birds react as though they’re hearing a bird making an alarm call.

This is what the whistle sounds like [whistle] and this is what the buzzing sounds like [buzz].

Richard E. recently tweeted some amazing pictures of beetles and suggested we cover more beetles, and I totally agree! We’ll finish with a beetle that makes this weird creaky sound:

[beetle sound]

The Asian longhorned beetle is sometimes called the starry sky beetle because it’s black with white dots. It’s native to eastern China and Korea, but it’s an invasive species in North America, parts of Europe, and other parts of Asia. It can grow about an inch and a half long, or 4 cm, but its antennae are up to twice as long as its whole body.

The female chews little holes in the bark of a tree and lays a single egg in each hole. When the larva hatches, it burrows deeper into the tree, eating sap and wood, until it’s ready to pupate. When it emerges as an adult, it chews its way out of the tree for the first time in its life, and flies away to find a mate. It especially likes poplar, maple, and willow trees. If enough beetle larvae are eating their way through a tree, the tree becomes weakened and can lose branches or even die.

There are lots of other species of longhorned beetle, though, and a lot of them make creaky scraping sounds. The male has ridges on his head that he scrapes along his thorax to attract a mate.

The white-spotted sawyer, also called the pine beetle, is native to North America and is black with a single white spot at the base of the wings, and sometimes with more white spots on the wings. It looks a lot like the Asian longhorned beetle but has black antennae whereas the Asian beetle has black and white antennae.

Like the many other longhorned beetle species, the female chews little holes in a tree to lay eggs in, but in this case she prefers pine and spruce trees, especially ones that are dead or dying or have sustained fire damage. The male white-spotted sawyer finds a good tree and defends it from other males, and if a female likes the tree she’ll mate with the male. But while the male keeps other males away, other females sometimes sneak in and lay eggs in the holes the female has already chewed in the tree. These nest holes take a long time to make and if a female can sneak some of her eggs into holes another female has already made, it saves her a lot of effort.

In addition to the male making a creaking noise to attract a mate, longhorned beetle larvae just generally make a lot of noises as they chew their way through a tree. If you’re ever walking through the woods and hear this sound, now you know what it is:

[creaky beetle sound]

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 269: Gila Monsters, Basilisks, and Sand Boas, oh my!

Thanks to Zachary, Enzo, and Oran for their suggestions this week! Let’s learn about some interesting reptiles!

Happy birthday to Vale! Have a fantastic birthday!!

The magnificent Gila monster:

The Gila monster’s tongue is forked, but not like a snake’s:

The remarkable green basilisk (photo by Ryan Chermel, found at this site):

A striped basilisk has a racing stripe:

I took this photo of a basilisk myself! That’s why it’s a terrible photo! The basilisk is sitting on a branch just above the water, its long tail hanging down:

The desert sand boa:

Show transcript:

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

This week we’re going to learn about three weird and interesting reptiles, with suggestions from Zachary, Enzo, and Oran, including a possible solution to a mystery animal we’ve talked about before!

But first, we have a birthday shoutout! A very happy birthday to Vale! You should probably get anything you want on your birthday, you know? Want a puppy? Sure, it’s your birthday! Want 12 puppies? Okay, birthday! Want to take your 12 puppies on a roadtrip in a fancy racecar? Birthday!

Our first suggestion is from Enzo and Zachary, who both wrote me at different times suggesting an episode about the Gila monster. How I haven’t already covered an animal that has monster right there in its name, I just don’t know.

The Gila monster is a lizard that lives in parts of southwestern North America, in both the United States and Mexico. It can grow up to two feet long, or 60 cm, including its tail. It’s a chonky, slow-moving lizard with osteoderms embedded in its skin that look like little pearls. Only its belly doesn’t have osteoderms. This gives it a beaded appearance, and in fact the four other species in its genus are called beaded lizards. Its tongue is dark blue-black and forks at the tip, but not like a snake’s tongue. It’s more like a long lizard tongue that’s divided at the very end.

The Gila monster varies in color with an attractive pattern of light-colored blotches on a darker background. The background color is dark brown or black, while the lighter color varies from individual to individual, from pink to yellow to orange to red. You may remember what it means when an animal has bright markings that make it stand out. It warns other animals away. That’s right: the Gila monster is venomous!

The Gila monster has modified salivary glands in its lower jaw that contain toxins. Its lower teeth have grooves, and when the lizard needs to inject venom, the venom flows upward through the grooves by capillary force. Since it mostly eats eggs and small animals, scientists think it only uses its venom as a defense. Its venom is surprisingly toxic, although its bite isn’t deadly to healthy adult humans. It is incredibly painful, though. Some people think the Gila monster can spit venom like some species of cobra can, but while this isn’t the case, one thing the Gila monster does do is bite and hold on. It can be really hard to get it to let go.

The fossilized remains of a Gila monster relative were discovered in 2007 in Germany, dating to 47 million years ago. The fossils are well preserved and the lizard’s teeth already show evidence of venom canals. The Gila monster is related to monitor lizards, although not closely, and for a long time people thought it was almost the only venomous reptile in the world. These days we know that a whole lot of lizards produce venom, including the Komodo dragon, which is a type of huge monitor lizard.

In 2005, a drug based on a protein found in Gila monster venom was approved for use in humans. It helps manage type 2 diabetes, and while the drug itself is synthetic and not an exact match for the toxin protein, if researchers hadn’t started by studying the toxin, they wouldn’t have come up with the drug.

The Gila monster lives in dry areas with lots of brush and rocks where it can hide. It spends most of its time in a burrow or rock shelter where it’s cooler and the air is relatively moist, and only comes out when it’s hungry or after rain. It eats small animals of various kinds, including insects, frogs, small snakes, mice, and birds, and it will also eat carrion. It especially likes eggs and isn’t picky if the eggs are from birds, snakes, tortoises, or other reptiles. It has a keen sense of smell that helps it find food. During spring and early summer, males wrestle each other to compete for the attention of females. The female lays her eggs in a shallow hole and covers them over with dirt, and the warmth of the sun incubates them.

The Gila monster is increasingly threatened by habitat loss. Moving a Gila monster from a yard or pasture and taking it somewhere else actually doesn’t do any good, because the lizard will just make its way back to its original territory. This is hard on the lizard, because it requires a lot of energy and exposes it to predators and other dangers like cars. It’s better to let it stay where it is. It eats animals like mice and snakes that you probably would rather not have in your yard anyway, and as long as you don’t bother it, it won’t bother you. Also, it’s really pretty.

Next, Oran wants to learn more about the basilisk lizard. We talked about it very briefly in episode 252 and I actually saw two of them in Belize, so they definitely deserve more attention.

The basilisk lives in rainforests from southern Mexico to northern South America. There are four species, and a big male can grow up to three feet long, or 92 cm, including his long tail. The basilisk’s tail is extremely long, in fact—up to 70% of its total length.

Both male and female basilisks have a crest on the back of the head. The male also has a serrated crest on his back and another on his tail that make him look a little bit like a tiny Dimetrodon.

The basilisk is famous for its ability to run across water on its hind legs. The toes on its large hind feet have fringes of skin that give the foot more surface area and trap air bubbles, which is important since its feet plunge down into the water almost as deep as the leg is long. Without the air trapped under its toe fringes, it wouldn’t be running, it would be swimming. It can run about 5 feet per second, or 1.5 meters per second, for about three seconds, depending on its weight. It uses its long tail for balance while it runs.

When a predator chases a basilisk, it rears up on its hind legs and runs toward the nearest water, and when it comes to the water it just keeps on running. The larger and heavier the basilisk is, the sooner it will sink, but it’s also a very good swimmer. If it’s still being pursued in the water, it will swim to the nearest tree and climb it, because it also happens to be a really good climber.

The basilisk can also close its nostrils to keep water and sand out, which is useful because it sometimes burrows into sand to hide. It can also stay underwater for as long as 20 minutes, according to some reports. It will eat pretty much anything it can find, including insects, eggs, small animals like fish and snakes, and plant material, including flowers. It mostly eats insects, though.

Fossil remains of a lizard discovered in Wyoming in 2015 may be an ancestor to modern basilisks. It lived 48 million years ago and probably spent most of its time in trees. It had a bony ridge over its eyes that shaded its eyes from the sun and also made it look angry all the time. It grew about two feet long, or 61 cm., and may have already developed the ability to run on its hind legs. We don’t know if it could run on water, though.

Finally, Zachary also suggested the sand boa. Sand boas are non-venomous snakes that are mostly nocturnal. During the day the sand boa burrows deep enough into sand and dirt that it reaches a cool, relatively moist place to rest. At night it comes out and hunts small animals like rodents. If it feels threatened, it will dig its way into loose soil to hide. It’s a constrictor snake like its giant cousin Boa constrictor, but it’s much smaller and isn’t aggressive toward humans.

Zachary thinks that the sand boa might actually be the animal behind sightings of the Mongolian death worm. We’ve talked about the Mongolian death worm in a few episodes, most recently in episode 156.

The Mongolian death worm was first mentioned in English in a 1926 book about paleontology, but it’s been a legend in Mongolia for a long time. It’s supposed to look like a giant sausage or a cow’s intestine, reddish in color and said to be up to 5 feet long, or 1.5 meters. It mostly lives underground in the western or southern Gobi Desert, but in June and July it surfaces after rain. Anyone who touches the worm is supposed to die painfully, although no one’s sure how exactly it kills people. Some suggestions are that it emits an electric shock or that it spits venom.

Mongolia is in central Asia and is a huge but sparsely populated country. At least one species of sand boa lives in Mongolia, although it’s rare. This is Eryx miliaris, the desert sand boa. Females can grow up to 4 feet long, or 1.2 meters, while males are usually less than half that length. Until recently it was thought to be two separate species, and sometimes you’ll see it called E. tataricus, but that’s now an invalid name.

The desert sand boa is a strong, thick snake with a blunt tail and a head that’s similarly blunt. In other words, like the Mongolian death worm it can be hard to tell at a glance which end is which. Its eyes are small and not very noticeable, just like the death worm. It’s mostly brown in color with some darker and lighter markings, although its pattern can be quite variable. Some individuals have rusty red markings on the neck.

It prefers dry grasslands and will hide in rodent burrows. When it feels threatened, it will coil its tail up and may pretend to bite, but like other sand boas it’s not venomous and is harmless to humans.

At first glance, the desert sand boa doesn’t seem like a very good match with the Mongolian death worm. But in 1983, a group of scientists went searching for the death worm in the Gobi. They were led by a Bulgarian zoologist named Yuri Konstantinovich Gorelov, who had been the primary caretaker of a nature preserve in Mongolia for decades and was familiar with the local animals. The group visited an old herder who had once killed a death worm, and in one of those weird coincidences, while they were talking to the herder, two boys rushed in to say they’d seen a death worm on a nearby hill.

Naturally, Gorelov hurried to the top of the hill, where he found a rodent burrow. Remember that this guy knew every animal that lived in the area, so he had a good idea of what he’d find in the burrow. He stuck his hand into it, which made the boys run off in terror, and pulled out a good-sized sand boa. He draped it around his neck and sauntered back to show it to the old herder, who said that yes, this was exactly the same kind of animal he’d killed years before.

That doesn’t mean every sighting of a death worm is necessarily a sand boa. I know I’ve said this a million times, but people see what they expect to see. The death worm is a creature of folklore, whether or not it’s based on a real animal. If you hear the story of a dangerous animal that looks like a big reddish worm with no eyes and a head and tail that are hard to distinguish, and you then see a big snake with reddish markings, tiny eyes, and a head and tail that are hard to distinguish, naturally you’ll assume it’s a death worm.

At least some sightings of the death worm are actually sightings of a sand boa. But some death worm sightings might be due to a different type of snake or lizard, or some other animal—maybe even something completely new to science. That’s why it’s important to keep an open mind, even if you’re pretty sure the animal in question is a sand boa. Also, maybe don’t put your bare hand in a rodent burrow.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 267: The Mystery Sauropod

Show transcript:

Hi. If you’re hearing this, it means I’m sick or something else has happened that has kept me from making a new episode this week. This was a Patreon bonus episode from mid-August 2019. I think it’s a good one. If you’re a Patreon subscriber, I’m sorry you don’t have a new episode to listen to this time. Hopefully I’ll be feeling better soon and we can get back to learning about lots of strange animals.

Welcome to the Patreon bonus episode of Strange Animals Podcast for mid-August, 2019!

While I was doing research for the paleontology mistakes and frauds episodes, I came across the discovery of what might have been the biggest land animal that ever lived. But while I wanted to include it in one episode or the other, it wasn’t clear that it was either a mistake or a fraud. It might in fact have been a real discovery, now lost.

In late 1877 or early 1878, a man named Oramel Lucas was digging up dinosaur bones for the famous paleontologist Edward Cope. Cope was one of the men we talked about in the paleontological mistakes episode, the bitter enemy of Othniel Marsh. Lucas directed a team of workers digging for fossils in a number of sites near Garden Park in Colorado, and around the summer of 1878 he shipped the fossils he’d found to Marsh. Among them was a partial neural arch of a sauropod.

The neural arch is the top part of a vertebra, in this case probably one near the hip. Sauropods, of course, are the biggest land animals known. Brontosaurus, Apatosaurus, and Diplodocus are all sauropods. Sauropods had long necks that were probably mostly held horizontally as the animal cropped low-growing plants and shrubs, and extremely long tails held off the ground. Their legs were column-like, something like enormous elephant legs, to support the massively heavy body.

We know what Diplodocus looked like because we have lots of Diplodocus fossils and can reconstruct the entire skeleton, but for most other sauropods we still only have partial skeletons. The body size and shape of other sauropods are conjecture based on what we know about Diplodocus. In some cases we only have a few bones, or in the case of Cope’s 1878 sauropod, a single partial bone.

Cope examined the neural arch, sketched it and made notes, and published a formal description of it later in 1878. He named it Amphicoelias [Am-fi-sil-i-as] fragillimus.

The largest species of Diplodocus, D. hallorum, was about 108 feet long, or 33 meters, measuring from its stretched-out head to the tip of its tail. Estimates of fragillimus from Cope’s measurement of the single neural arch suggest that its tail alone might be longer than Diplodocus’s whole body.

Cope measured fragillimus’s partial neural arch as 1.5 meters tall, or almost five feet. That’s only the part that remained. It was broken and weathered, but the entire vertebra may have been as large as 2.7 meters high, or 8.85 feet. From that measurement, and considering that fragillimus was seemingly related to Diplodocus, even the most conservative estimate of fragillimus’s overall size is 40 meters long, or 131 feet, and could be as long as 60 meters, or 197 feet. This is far larger than even Seismosaurus, which is estimated to have grown 33.5 meters long, or 110 feet, and which is considered the largest land animal known.

So why isn’t fragillimus considered the largest land animal known? Mainly because we no longer have the fossil to study. It’s completely gone with no indication of where it might be or what happened to it. And that has led to some people thinking that it either never existed in the first place, or that Cope measured it wrong.

One argument is that Cope wrote down the measurements wrong and that the neural arch wasn’t nearly as large as Cope’s notes indicate. But Lucas, who collected the fossil, always made his own measurements and these match up with what Cope reported. Lucas and Cope both remarked on the size of the fossil, which was far larger than any they had ever found.

Oddly, Cope’s nemesis Marsh inadvertently vouches for him by the things Marsh didn’t do. We know that Marsh kept tabs on Cope, including even paying people to spy on his fossil excavations. Marsh was also always ready to pounce on any of Cope’s mistakes and make them a big deal. But Marsh never said anything about the neural arch not being a real find, and never questioned Cope’s measurements of it.

Cope never mentioned what happened to the fossil. It wasn’t until 1921 that two researchers pointed out that it was missing from the Cope Collection. So what happened to it?

Most researchers suspect it just crumbled away. The fossil formed in a type of rock called mudstone, which fractures easily into little irregular cubes. In fact, Cope gave the sauropod the name fragillimus because the fossil appeared so fragile—not because of the mudstone per se, but because so much of the fossil had already weathered away and as a result it looked too delicate to be part of such a large animal.

These days paleontologists treat fossils with various preservatives to harden them, but that practice didn’t start until 1880, several years after the neural arch was found. Cope only made one drawing of it, which wasn’t his usual practice. It’s possible the fossil was so delicate at that point that just turning it over to draw the other side caused it to fall apart. Many researchers suspect that Cope or one of his assistants eventually discarded it after it crumbled into a pile of mudstone blocks.

Obviously, if we don’t have the fossil Cope examined, maybe we should go looking for more fossils that Cope’s workers might have missed. Cope did mention a femur located near the neural arch that may have been another fragillimus bone, but it’s not clear if the femur was actually collected. We have Cope’s journal entry where he sketched the dig sites Lucas was working, a rough map that shows at least seven sites. But it’s been a century and a half since then and most of the sites have been lost. In 1994 a team tried to relocate the site where Lucas found the neural arch, but without luck. It’s also possible that any remaining fossils have weathered away completely. In the dig sites that have been found, the mudstone has mostly weathered away down to the underlying sandstone.

Researchers have been able to estimate a probable age for fragillimus from Cope’s notes about the stratigraphy where the neural arch was found. Fragillimus probably lived in the late Jurassic, roughly 150 million years ago. This matches up with the age of other enormously large sauropods. But if fragillimus really was so much larger than the others, how did it live? Would an animal that size actually be able to support its weight, feed itself, and function overall? Wouldn’t it overheat in the sun or starve due to not finding enough food to power its colossal body?

Researchers think that sauropods grew to such enormous sizes because their food was nutritionally lacking. That doesn’t make sense until you realize that when a herbivore’s food is poor, the longer it can keep the plant material in its digestive system, the more nutrients it can extract from it. Sauropods were probably hindgut fermenters like all modern herbivorous reptiles and a lot of birds. The best way to keep lots of plant material in the digestive system is to be really big and have a really big digestive tract. This is the case with many herbivores today, like elephants, rhinos, and horses. Other benefits come from being extremely large, too, such as being larger than potential predators.

Sauropods generally lived in semiarid savannas. Grass hadn’t evolved yet, so researchers think the main groundcover plant was ferns, which sauropods probably ate in bulk. There would also have been shrubs, small trees, and some areas with much taller trees. It’s possible that sauropods spent most of the day among the trees, sleeping in the shade, and came out at night to do most of their grazing.

Cope also found fossils from another sauropod that he named Amphicoelias altus. In fact, he described both Amphicoelias species in the same paper. Some researchers have therefore suspected that the two species were actually the same. A. altus is estimated to grow about the same size as Diplodocus, about 82 feet long, or 25 meters.

But in 2018, a paleontologist named Kenneth Carpenter examined Cope’s information on fragillimus and came to some interesting conclusions. He reclassified it from the family Diplodocidae to the family Rebbachisauridae and renamed it Maraapunisaurus fragillimus. As a result, the estimates of its size have changed. Carpenter suggests that it was much smaller, about 99 feet long, or 30 meters, but that Cope’s measurements were correct. Sauropods of this family just have larger vertebrae than Diplodocidae.

The only difficulty with fragillimus being a member of the Rebbachisauridae is that this group of sauropods isn’t known to have lived in North America, just Europe and South America. But the fossil record is incomplete and every find requires researchers to adjust what we know about where dinosaurs lived and how widespread a particular species or family was.

Hopefully, eventually more and better remains of fragillimus will turn up soon. Then we can work out exactly how big it really was.

Thanks for your support, and thanks for listening! The next episode in the main feed will be about an unusual small fish and an extinct pig relative called the unicorn pig. Basically both those animals should have gone in other episodes but I messed up and forgot to add them to strangest small fish and the weird pigs episodes, but they’re both really neat and I wanted to share them.

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Episode 263: Pair Bonds

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Thanks to Ella and Jack for this week’s topic suggestion, animals that mate for life or develop pair bonds! Happy Valentine’s Day!

Further reading:

Wisdom the albatross, now 70, hatches yet another chick

The prairie vole mates for life:

Swans mate for life:

The black vulture also mates for life:

The Laysan albatross:

Wisdom the Laysan albatross with her 2021 chick (pic from the link listed above). I hope I look that good at 70:

Dik-diks!

The dik-dik nose is somewhat prehensile:

The pileated gibbon (and other gibbons) forms pair bonds:

Show transcript:

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

Last February Ella and her son Jack suggested a Valentine’s Day topic. I already had the February episodes finished last year, but this year Valentine’s Day falls on a Monday and that just seems too perfect to pass up. So thanks to Ella and Jack, we’re going to learn about some animals that are monogamous.

Valentine’s Day falls on February 14th and in many European cultures is a day celebrating love and romance. It also falls at the very beginning of spring in the northern hemisphere, when many animals start finding mates.

Different species of animal have different relationships. Some animals are social, some are solitary. Every species is different because every species has slightly different requirements for reproducing due to different habitats, foods, how much care the babies need, and so forth.

There are different types of monogamy among animals and it can get complicated, just as it’s often complicated in people, so I’m going to simplify it for this episode into two categories: animals that mate for life and animals that form pair bonds. Animals that mate for life, meaning the male and female seek each other out every mating season to have babies together, don’t necessarily spend all their time together outside of mating season. Animals in pair bonds spend a lot of their time together, but they don’t always exclusively mate with each other. But some animals do both.

For instance, the prairie vole. This is a little rodent that lives in dry grasslands in central North America, in parts of the United States and Canada. It’s about the size of a mouse with a short tail although it’s more chonky than a mouse, like a small dark brown hamster. It spends most of its time either in a shallow burrow it digs among grass roots or out finding the plant material and insects it eats by traveling through aboveground tunnels it makes through densely packed plant stems. It lives in colonies and is a social animal most of the time, and the male in particular is devoted to his mate. He’s so devoted that once he’s found a mate, he will even drive away other females who approach him.

The only time the prairie vole isn’t social is during mating season, which is usually twice a year, in fall and in spring. At that time, mated pairs leave the colony and find a small territory to have their babies. The pair spends almost all their time together, grooming each other, finding and sharing food, and building a nest for the babies. When the babies are born, both parents help care for them.

The male prairie vole mates for life. Most of the time “mating for life” means that if one of a pair dies, the other will then find a new mate. But for the male prairie vole, if his mate dies, he stays single for the rest of his life. He also shows behaviors that are similar to grief in humans. The female prairie vole is a little more practical and although she also grieves if her mate dies, she’ll eventually find another mate. Researchers who study prairie voles have discovered that the hormones found in mated pairs are the same as those in humans who are in love.

That’s so sweet, and I wish I didn’t have to talk about the voles dying. I think the opposite of love isn’t hate; the opposite of love is grief. It’s okay to be sad even for a long time when someone you love dies or moves far away, or if your own pair bond doesn’t work out. It’s also okay to find happy moments even when you’re grieving. Life is complicated. Also, just going to point out, devoted as they are to each other, sometimes a prairie vole will mate with someone besides their own mate.

One bird that’s famous for being monogamous is the swan. It mates for life and also forms pair bonds. These pair bonds form while the swans are still young, and the young couples basically just hang out together long before they’re old enough to have babies. It’s no wonder pictures of swans appear on so many wedding invitations and Valentine’s day cards. It helps that they’re beautiful birds too. The black vulture also mates for life but no one puts vultures on a wedding invitation. Also, swans sometimes split up and find new mates. Things don’t always work out with a pair bond, even for swans.

Another large, beautiful bird that mates for life is the albatross, but it doesn’t form a pair bond. Most of the time the albatross is solitary, traveling thousands of miles a year as it soars above the open ocean, looking for squid, small fish, and other food near the surface of the water. But once a year in some species, and once every two years in other species, albatrosses return to their nesting grounds and seek out their mate.

Albatrosses live a very long time so are really picky about who they choose as a mate. Once a pair forms, they develop a complicated, elegant dance to perform together. Each couple’s dance is unique, which helps them find each other in a crowded nesting colony when they haven’t seen each other in a couple of years.

The oldest wild bird in the world that we know of is a Laysan albatross named Wisdom. She was tagged by scientists in 1956 when she was at least five years old already, and as of 2021 she was still healthy and producing healthy chicks with her mate. Her leg tag has had to be replaced six times because she’s outlasting the material used to make the tags.

The Laysan albatross is a smaller species of albatross, with a wingspan of not quite 7 feet, or over two meters. Its body is mostly white, although its back is gray, with black and gray wings and a dark smudge across the eyes that looks very dramatic. It spends most of the time in the northern Pacific between the west coast of North America and the east coast of Asia, but it only nests on 16 tiny islands. Most of these are part of the Hawaiian islands with a few near Japan, but recently new breeding colonies have been spotted on islands off the coast of Mexico.

Wisdom the albatross is estimated to be at least 70 years old as of 2021 and she’s raised 30 to 36 chicks successfully. Because of her age, which is old even for an albatross, she may have outlived her first mate and taken another. She’s been with her current mate since at least 2012.

Albatrosses only lay one egg during nesting season. Both parents help incubate the egg and feed the baby when it hatches. It takes two or three months for the egg to hatch, depending on the species. Once the egg hatches, it’s at least another 5 or 6 months before the chick is old enough to leave the nest and care for itself, and in some species this is as much as 9 months. This means a big time and energy investment for both parents.

Albatrosses don’t reach sexual maturity until they’re at least five years old. Birds younger than this still join the breeding colony and practice their dance moves for when they’re old enough to choose a mate.

Pair bonding and mating for life are common in birds, rare in amphibians, reptiles, and fish, and surprisingly rare in mammals. One mammal that both mates for life and forms a pair bond is a tiny antelope called a dik-dik.

The dik-dik lives in parts of eastern and southern Africa and is barely bigger than a rabbit, which it somewhat resembles in shape. It stands less than 16 inches tall at the shoulder, or 40 cm, although its back and rump are arched and rounded and so are actually higher than the shoulder. Females are usually larger than males, while only males have horns. The horns arch back from the head but because the male has a tuft of long hair on the top of his head, and because the horns are only about 3 inches long at most, or 7.5 cm, they can be hard to see.

The dik-dik has an elongated snout that’s somewhat prehensile. It lives in hot areas without much water, so it gets most of its moisture from the plants it eats. Most of the time hot weather doesn’t bother it, but on exceptionally hot days it can cool down by panting through its long nose. Its nose is lined with blood vessels close to the surface and it has special nose muscles that allow it to pant quickly. Air moving over the blood vessels helps cool the blood.

Because pretty much everything eats the dik-dik, traveling long distances to find a mate is dangerous. Once the dik-dik finds a mate, they stay together for life in a small territory and spend most of their time together. Females give birth to one fawn twice a year, and the fawn no longer needs its parents at about 7 months old. Parents drive away their grown offspring, who leave to find a mate and territory of their own.

Humans, of course, strongly pair bond because we’re such intensely social creatures, and many people choose a partner and stay with them for life. Then again, we don’t always. Surprisingly, our closest living cousins, the great apes, are also very social, but they don’t typically form pair bonds and females may mate with different males.

The gibbon, which is a lesser ape instead of a great ape, does often form long-lasting pair bonds. We’ve talked about various species of gibbon in previous episodes. Gibbons are the apes that sing elaborate duets with their mates, with their children sometimes joining in as a chorus.

Here’s a pair of pileated gibbons singing together. The female is named Molly and was in a rehabilitation center after being injured, but she found a wild mate while she was recovering:

[gibbons singing]

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. 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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!