Episode 165: Furry Fish

I hope you’re all well and not too bored if you’re one of the millions who are having to stay inside right now! This week let’s learn about a fishy mystery, fish with fur!

Further reading:

Mirapinna esau – a Furry Fish from the Azores

The so-called fur-bearing trout:

A hairy frogfish:

The hairyfish (I couldn’t find any actual photos of one):

This man is serious about moldy fish. He wants the mold to think about what it’s done while it’s in time out:

Show transcript:

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

This week let’s learn about a fishy mystery, if not an actual mystery fish. Are there any fish with hair?

Sometimes you’ll see a mounted fish that has fur, usually decorating a restaurant. It may be the same type of restaurant that also has a stuffed jackalope, which we talked about in episode 113. Fur-bearing trout are jokes by taxidermists, who usually attach rabbit fur to a stuffed fish.

But some cultures have stories about fish with hair. This includes the Japanese story of big river fish with hair on their heads like people, although since these fish are supposed to come out of the water at night to fight and play, they’re probably not actual fish. There’s also an Icelandic legend about an inedible trout with fur that shows up in rivers where people are not being nice enough.

Could these stories be based on a real animal? Are there any fish that grow fur or hair?

Mammals are the only living animals that grow actual hair from specialized cells, but lots of animals have hair-like coverings. Baby birds have downy fuzzy feathers that look like hair and many insects have hairlike structures called setae [see-tee], made of chitin, that make them look furry.

Some fish grow hairlike filaments that help camouflage them among water plants and coral. We’ve talked about the frogfish and its relatives, the anglerfish, many times before, because they’re such weird-looking fish, many of them deep-sea species that are seldom seen. The hairy frogfish isn’t a deep-sea species, though. It lives in warm, shallow waters, especially around coral reefs, and grows to about 8 inches long, or 20 cm. The hairlike filaments that cover its body help it blend in among seaweed and anemones. It’s usually brownish-orange or yellowish, but it can actually change its color and pattern to help it blend in with its surroundings. This color change doesn’t happen fast, though. It takes a few weeks.

Like other frogfish, it has a modified dorsal spine called an illicium with what’s called an esca at the end. In deep-sea species of anglerfish, the esca contains bioluminescent bacteria, but in the hairy frogfish it just looks like a worm. The fish sits immobile except for the illicium, which it twitches around. When a fish or other animal comes to catch what looks like a worm swimming around in the water, the frogfish goes YOMP and gulps the animal down. Like other frogfish species, the hairy frogfish has large, strong pectoral and pelvic fins that it uses to walk across the sea floor instead of swimming.

Another fish that looks like it has hair is called the hairyfish. The hairyfish barely grows more than two inches long, or 5.5 cm. It eats copepods and other tiny crustaceans that live near the ocean’s surface and it’s covered with small hairlike filaments. Its close relations are equally small fish called tapetails because its tail fin has a narrow extension at least as long as the rest of its body called a streamer. The tapetail was described in 1956 but scientists were confused because no one had ever found an adult tapetail, just young ones. It wasn’t until 2003 that a team of Japanese scientists discovered that the DNA of tapetails matched the DNA of a deep-sea fish called the flabby whalefish. There are lots of whalefish species, but the largest only grows to about 16 inches long, or 40 cm. It looks very different from its larval form, with loose skin without scales or hair-like filaments or the tail streamer. But even after researchers figured out that the tapetail and hairyfish are larvae of whalefish, there was still another mystery. All the whalefish ever found were females. Where were the males? Finally they identified yet another deep-sea fish called a bignose fish as the male of the species. The bignose fish has a huge liver but its mouth doesn’t go anywhere—it doesn’t have a throat or stomach. It gets its name from a bulge on its snout that gives it a keen sense of smell.

It turns out that after a larval whalefish develops into an adult, the male doesn’t need to eat. It lives off the fat and nutrients stored in its huge liver and uses its sense of smell to find a female in the depths of the ocean. The female remains a carnivore, eating any small animals it can catch, and it often migrates at night from the deep sea to nearer the surface, then returns to the depths during the day. So far we don’t know which species the hairyfish develops into as an adult.

But the hairy frogfish and the hairyfish are both rarely seen marine fish. Are there hairy-looking freshwater fish that might have inspired the legends of furry fish?

There is a disease called cotton mold that infects fish and makes them look like they have white or grayish spots of fur. Saprolegnia is the name of the mold, which lives in water and can infect fish in the wild and in aquariums. It mostly prefers cold fresh water and usually infects fish that are already injured. It spreads across the fish’s skin and makes it look fuzzy, and eventually it kills the fish. Salmon and trout are common targets of this mold, which may be the source of the Icelandic story.

As for the Japanese story about the hairy fish creatures that come out of the river at night, zoologist Karl Shuker suggests the legend may be based on sightings of the northern fur seal. While seals are mammals, not fish, they do look superficially like fish, and while seals also usually live in the ocean, they occasionally stray into rivers.

So that seems to cover the hairy fish mystery. But next time you go on a fishing trip or just hang out in a boat, keep an eye out for fish with fur just in case.

You can find Strange Animals Podcast online 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. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 163: Three Weird Fish

Thanks to Nathan for his suggestions! This week we’re going to learn about three strange and interesting fish!

A northern snakehead:

A giant snakehead:

A Greenland shark, fish of mystery:

The upside-down catfish is indeed upside down a lot of the time (this is actually a picture of Synodontis nigriventris, closely related to the upside-down catfish we talk about in the episode):

An ancient Egyptian upside-down catfish pendant that ladies wore in their hair:

Show transcript:

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

We haven’t done a fish episode in a while, so this week let’s learn about three weird fish. Thanks to Nathan for suggesting the first two fish, the snakehead and the Greenland shark.

The snakehead is a freshwater fish that gets its name because while it’s an ordinary-looking fish for the most part, it has a flattened head that looks a little bit like a snake’s. Different species of snakehead look different in other ways, of course, so let’s examine a couple of typical species.

The northern snakehead is native to Asia, but it’s been introduced into other parts of the world by accident or as a food fish. It’s one of the largest species, with reports of some specimens growing up to five feet long, or 1.5 meters. It’s usually no more than three feet long, though, or 1 meter. It’s brown with darker blotches and has sharp teeth that it uses to catch fish, frogs, and other small animals.

Like other snakeheads, the northern snakehead can breathe air and survive out of water for several days as long as it stays damp. Young snakeheads can even wriggle considerable distances on land to find water. It likes stagnant or slow-moving water.

Because it’s a fierce predator that can find its way to new waterways, introduced snakeheads are invasive species that can cause havoc to populations of native fish. The northern snakehead has been introduced into many waterways in the United States in the last twenty years, as a result of people releasing unwanted aquarium fish and accidental release of snakeheads in fish-farming operations. Since snakeheads reach mature age quickly and females can lay thousands of eggs at a time, snakeheads are illegal to own in many places now and release snakeheads into the wild is even more against the law.

The giant snakehead also grows up to five feet long, or 1.5 m, and is from parts of southeast Asia. Young giant snakeheads are red, but when they grow up they’re black and white with a thick black stripe down each side. It’s also been introduced into a lot of places as a food fish and a game fish, but since it’s a tropical species it can’t survive colder weather and isn’t as invasive as a result, at least not outside of tropical and subtropical areas.

The giant snakehead can be aggressive, though, especially when it’s guarding its nest. Both parents act as guards of the eggs and the newly hatched babies, which follow their mother around wherever she goes. That’s actually really cute.

Next let’s talk about the Greenland shark. We covered it briefly in episode 74, about colossal squid and the things that eat them, but mostly we talked about its close relative the sleeper shark. The Greenland shark is similar in some ways but it’s much bigger than the sleeper shark. It lives in the North Atlantic and Arctic Oceans where the water is barely warmer than the freezing point and it grows up to 24 feet long, or 7.3 meters, with females being larger than males.

But despite how enormous it is, it’s not a shark you need to worry about. First of all, what are you doing swimming in water that cold? Second, the Greenland shark is a slow swimmer, no more than about 1 ½ miles per hour, or 2.6 km/h. You can walk faster than that without even trying. You can probably dog-paddle faster than that.

And yet, the Greenland shark manages to eat seals and fish and other animals that move quickly. Since no one’s actually observed a Greenland shark hunting, no one knows how they catch prey. Some researchers speculate that it sneaks up on sleeping seals and grabs them. It also eats a lot of carrion, including dead moose and reindeer and polar bears that fall into the water and drown. One shark was found with an entire reindeer in its stomach.

The Greenland shark spends winter in shallow water where it’s warmer, but in summer it spends more time in deep water. At least one submersible observed a Greenland shark 7,200 feet below the surface of the ocean, or 2,200 meters. Occasionally a Greenland shark travels more widely, usually in deep water where the water is cold. In 2013 one was caught by researchers in the Gulf of Mexico, which is way far away from the Arctic. It was swimming at over 5,700 feet deep, or 1,750 meters.

The Greenland shark is adapted to the cold and pressure of the deep sea in many ways. Its blood contains three types of hemoglobin, which help it absorb as much oxygen as possible from water that’s poorly oxygenated to start with. Its muscles and other tissues contain high levels of urea and other compounds that increase its buoyancy, so that it doesn’t need to work as hard to stay in one place. But the presence of urea in its muscles means that the Greenland shark not only tastes horrible, it’s toxic. In Iceland Greenland sharks are considered a delicacy, but only after the toxins have been removed from the meat by long treatment. This includes burying it in the ground for weeks, partially fermenting it, and drying it for several months afterwards. Most people don’t bother and any commercial fishing boats that catch Greenland sharks just toss them back overboard.

The Greenland shark has a very slow metabolism and grows extremely slowly too. That’s okay, though, because it lives a very long time. A VERY long time. The biggest Greenland sharks may be as much as 600 years old. Researchers examine the crystals in dead Greenland shark eyeballs to determine when they were hatched.

And speaking of Greenland shark eyeballs…some of you know where this is going. I hope you’re not eating grapes or anything right now. There’s a type of copepod, a crustacean, that acts as a parasite of the Greenland shark and the Pacific sleeper shark, its close relative. The copepod grows to about an inch long, or 28 mm, and attaches itself to the shark’s cornea, which is part of the eyeball. This impairs the shark’s vision but it doesn’t seem to care and it doesn’t seem to have any trouble finding food.

Okay let’s stop talking about that. Our third and final weird fish for this episode is a type of catfish that’s sometimes kept in aquariums. It’s called the upside-down catfish.

There are actually a number of closely-related catfish known as upside-down catfish, but the one we’ll talk about today is Synodontis batensoda. It lives in parts of Africa in marshy areas and slow-moving water. It grows to a little over a foot and a half long, or 50 cm, and eats plankton, algae, mollusks, insects and larvae, and crustaceans.

But the upside-down catfish gets its name from its habit of swimming upside down. Because it’s kept as an aquarium fish so often, many people assume that the upside-down swimming is something it developed because it’s kept in an enclosed aquarium habitat. But that’s actually not the case.

The catfish used to be well-known in Egypt, and there’s even an Egyptian tomb carving depicting a catfish swimming upside down, dating to the Middle Kingdom around 4,000 years ago. The upside-down catfish was often depicted in jewelry, too, including hair ornaments so beautifully made that the species of catfish can be determined. Young women in Egypt traditionally wore fish ornaments to decorate their braids. There’s a story about one young woman who was helping row a king across a lake when her fish pendant fell into the water. She stopped rowing, naturally, which messed up the other rowers. The king wanted to know why the boat had stopped, and when the woman explained, he offered to give her a new fish pendant. But no, she said, she wanted that one, the one that was now at the bottom of the lake. But the king had a magician who said no problem, and caused the water to fold back like a blanket, exposing the lake’s bottom so the pendant could be retrieved. I didn’t make that story up, either. It’s from the Westcar Papyrus that dates to around the 17th century BCE.

So why does the upside-down catfish swim upside down? Like other catfish, its mouth is angled downward so it can find food in the mud at the bottom of the water. So when it wants to grab an insect on the water’s surface, or eat algae off the bottom of a submerged leaf, it can only do so by turning upside down.

So that’s it for this week’s episode. I don’t know what else to say because I’m just sitting here trying to imagine how I’d manage if someone told me I had to swim upside down. But then, I can barely swim right side up. Good job, upside-down catfish!

You can find Strange Animals Podcast online 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. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 156: Animals of Mongolia

In honor of my new favorite band, The Hu, let’s learn about some animals from their country, Mongolia! (You can also watch the “Wolf Totem” video with English lyrics.)

The Hu. Oh my heart:

If you need the podcast’s feed URL, it’s https://strangeanimalspodcast.blubrry.net/feed/podcast/

A handsome prize-winning domesticated yak and rider (photo taken from this site):

The saiga, an antelope with a serious snoot:

A Bactrian camel (photo by *squints* Brent Huffman, looks like):

The taimen, a fish that would swallow you whole if it could:

Further watching:

A clip from the TV show Beast Man showing how moist the soil is in parts of the Gobi

Show transcript:

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

Recently, podcaster Moxie recommended a band she liked on her excellent podcast Your Brain on Facts. The band is called The Hu, spelled H-U, and she mentioned they were from Mongolia. I checked the band out and FELL IN LOVE WITH THEM OH MY GOSH, so not only have I been recommending them to everyone, I also want to learn more about their country. So let’s learn about some interesting animals from Mongolia.

But first, a quick note. About six months ago I had to migrate the site to an actual podcasting host, since I’d run out of memory on my own site. Well, there doesn’t seem to be any point to keep the old site open anymore since all the podcasting apps I checked appear to have the new feed and everything is on the new website. So in another week or two, the old site will close. If you suddenly stop receiving new episodes, please email me at strangeanimalspodcast@gmail.com and let me know what app you use for podcast listening, so I can get it updated. In the meantime, if your app gives you the option of entering a podcast feed manually, I’ve made a new page on the website, strangeanimalspodcast.blubrry.net, where you can copy and paste the feed URL. It’s also in the show notes. Feel free to contact me if you have any questions or if something isn’t working. Now, back to Mongolia and its animals.

Mongolia is located in Asia, north of China and south of Russia, with the Gobi Desert to the south and various mountain ranges to the north and west. You actually probably know some Mongolian history without realizing it. You’ve heard of the Great Wall of China, right? Well, it was built to keep out the Mongols, who would ride their horses into China and raid villages. Genghis Khan was the most famous Mongol in history, a fearsome warrior who conquered most of Eurasia in the early 13th century.

While you’re thinking about that, here’s a short clip of my favorite Hu song, called “Wolf Totem.” There’s a link in the show notes if you want to watch the official video.

Oh my gosh I love that song.

Anyway, Mongolia has short summers but long, bitterly cold winters. Many people are still nomadic, a traditional culture that’s horse-based. A lot of Mongolia is grassland referred to as the steppes, which isn’t very good for farming, but which is great for horses. Domesticated animals include horses, goats, and a bovid called the yak. Let’s start with that one.

The yak is closely related to both domestic cattle and to bison, and is a common domesticated animal in much of Asia. The wild yak is native to the Himalaya Mountains in Eurasia. It’s a different species from the domesticated yak and is larger, with a big bull wild yak standing up to 7.2 feet at the shoulder, or 2.2 meters. A big bull domesticated yak is closer to 4 ½ feet high at the shoulder, or almost 1.4 meters. The wild yak is usually black or brown, but domesticated yaks may be other colors and have white markings. Occasionally a wild yak is born that has golden fur.

Both male and female yaks have horns, although the males usually have larger horns with a broader spread than the females. The male also has a larger shoulder hump than the female, much like bison, and males are also larger and heavier. The reason the domesticated yak is so popular in the mountains and in areas where winters are long and cold, like Mongolia, is that it has long, dense hair with a soft undercoat that keeps it warm. It’s also naturally adapted to high altitudes where there’s less oxygen, with large lungs and heart. As a result, it doesn’t do well in lower altitudes and can even die of heat if it gets too warm, since it can’t sweat.

The yak is domesticated for its meat and milk, to pull plows, as a riding animal, and for its soft undercoat which is combed out in spring and used to make yarn. Even the yak’s droppings are useful, since they’re mostly undigested plant fibers that burn really well once they’re dry, so they can be used instead of wood to build fires.

In Mongolia, yak milk is used to make butter, cheese, and yogurt. And vodka. Yak races and yak festivals are increasingly popular as tourist attractions, but yak herding is a tradition dating back thousands of years.

The wild yak is a protected species where it still lives, mostly in China, India, and Tibet, but it’s still threatened by poaching and habitat loss due to domesticated yak herds pushing out their wild cousins. In the wild, the yak prefers to live in elevations too high for trees to grow. It eats grass and other plant material and can survive on a diet too poor to sustain cattle. This is because it has a larger rumen and the plants it eats can stay in its digestive tract for longer to extract as many nutrients as possible.

It’s rare for a domesticated animal to also be endangered, but yak herding in Mongolia is in steep decline, with 70% fewer yaks raised now than there were twenty years ago. There are a number of reasons for the decline. More people are moving to cities in Mongolia since they can make more money there instead of farming. Some farmers have started raising cattle or yak-cattle hybrids instead of yaks, since cattle and cattle hybrids produce more milk and meat even though they eat considerably more than yaks do. Worse, cloth made of sheep’s wool and other fibers is being exported by Chinese farmers labeled as Mongolian yak wool, which has caused the market for actual yak wool to crash. Yak wool is as soft and warm as cashmere, which comes from goats, but yaks are much better for the fragile mountain environment in Mongolia than goats are. Hopefully, increased tourism, including yak festivals, will help farmers make money from their traditional ways of life.

Instead of mooing like a cow, the yak grunts, although wild yak are usually silent. This is what a domesticated yak sounds like:

[yak grunting]

Another bovid, this one found only in Mongolia, is the Mongolian saiga. Some researchers consider it a subspecies of the saiga that was once found throughout Eurasia while others consider it a separate species. It’s critically endangered, possibly with as few as 5,000 animals left in the wild, threatened by poaching and competition with livestock. But the saiga frequently has twins instead of just one baby at a time, which helps its numbers increase quickly as long as people stop shooting the males for their horns. Some people think have medicinal qualities. They don’t, of course. The saiga almost went extinct back in the 1920s, but it recovered, so it can recover again as long as people leave it alone.

The saiga stands nearly three feet tall at the shoulder, or 81 cm, and its coat is usually a sandy pale brown in color. In winter it grows a long coat to keep warm. It’s also rather stocky in shape compared to other antelopes, which helps keep it warm too. But the main adaptation it has for cold weather is its nose. The saiga has a remarkable snoot. It almost looks like it has a little trunk. Its muzzle is considerably enlarged to make plenty of room for large nasal passages, which warms air before it reaches the lungs and also filters dust from the air. The nostrils point downward. The males have pale-colored horns that can grow nearly nine inches long, or 22 cm, although the closely related Russian saiga has horns that are almost twice that long. The horns grow upward and slightly back. The saiga migrates across the steppes and lives in herds that are sometimes quite large.

Another animal that’s domesticated but still lives wild in some parts of southern Mongolia and northern China is the Bactrian camel. That’s the camel that has two humps instead of just one. Like the yak, the domesticated and wild Bactrian camels are different species although they’re closely related. The wild Bactrian camel is smaller with a flatter head. A domesticated Bactrian camel can stand up to 7 ½ feet high at the shoulder, or 2.3 meters.

The wild Bactrian camel is critically endangered due to poaching and habitat loss, although it’s protected in both Mongolia and China. There may be only 1,000 of them left in the wild, and some of those are hybrids of wild and feral domesticated Bactrian camels. Since they’re different species, offspring of wild and domesticated Bactrian camels are often infertile. A wild Bactrian captive breeding program in Mongolia is underway and has been successful so far.

When you think of a camel, you probably think of a hot desert. Camels of all kinds are well adapted to desert life. The one-hump camel is a dromedary, which is a domesticated animal native to the Sahara Desert in northern Africa and other arid regions. But the two-humped Bactrian camel is adapted to a different kind of desert, the cold desert. Although it can get hot in the Gobi Desert in summer, winters are long and very cold, but mainly a desert just doesn’t get much rain. In the case of the Gobi, what little moisture it receives in winter is mainly from snow and frost, although it also gets an average of almost 8 inches of rain in the summer, or 19 cm.

The wild Bactrian camel, therefore, has to be able to survive without a lot of water. Some people think camels store water in their humps, but the humps are actually made up of fat. Fat is full of water, though, and when the camel can’t find any food or water, its body will reabsorb the fat to keep itself alive. If you see a camel with floppy or skinny humps, you know it’s not had much to eat recently and has had to use up its fat stores.

The wild Bactrian camel grows thick fur in winter to keep it warm in temperatures that can drop to -27 degrees Fahrenheit in winter, or -32.8 Celsius, but it sheds a lot of this heavy coat in summer when temperatures can soar to 99 F, or 37 C. Unlike most animals, it can safely eat snow without risking hypothermia, where the body core temperature falls to dangerous levels. It can also safely drink water that’s even saltier than the ocean. It lives in small herds that travel across the desert from one water source to another, since if it stayed in one area it would soon eat all the food available. It eats any plants it can find.

Mongolia has several rivers and lakes, so naturally it has some interesting water animals too. The taimen [TIE-min] is a large fish sometimes called the Eurasian river trout or Siberian giant trout, but it’s actually more closely related to the salmon. It lives in parts of Mongolia and Russia but is threatened by overfishing and water pollution. Until recently in Mongolia, people didn’t eat much fish, plus the taimen was considered the offspring of an ancient river spirit so was left alone. These days, unfortunately, not only are more people eating fish in Mongolia, sport fishing has become a big tourist draw. Conservationists are encouraging anglers to practice catch and release to save the remaining population.

The taimen grows up to six feet long, or two meters, and is a vicious predator. It will eat anything it can catch, including smaller taimen, and in fact will occasionally try to swallow a fish that’s too big, and will suffocate and die as a result. It lives in swift-moving water but is sometimes found in lakes. It grows slowly and lives a long time, and there are rumors of it hunting in packs. As a result, it’s sometimes called the river wolf. Stay away from anything called the river wolf, that’s my advice.

It wouldn’t be an episode about Mongolian animals if we didn’t talk about a mystery animal called the Mongolian death worm. We talked about it once before way back in episode ten, about electric animals, but that was a long time ago so let’s look at it again now.

The story goes that a huge wormlike creature lives in the western or southern Gobi Desert, and most of the time it stays below ground. During the rains of June and July it sometimes comes to the surface. It’s generally described as looking like a sausage or an intestine, red or reddish in color, as thick as a person’s arm, and as long as three or four feet, or up to about 1.5 meters. Its head and tail look alike, sort of like a giant fat earthworm, although some reports say it has some pointy bristles or spines at one end. Touching a death worm is supposed to lead to a quick, painful death, because why would you name something a death worm if it didn’t kill you? Some people report that it can even spit venom or emit an electrical shock that can kill people or animals at a distance.

The National Geographic Channel has a show called Beast Man, or used to, I don’t know, but in 2018 it aired an episode about the Mongolian death worm. I didn’t watch the whole episode, just clips, and while they didn’t actually find one, it was interesting. One lady they interviewed, who saw a death worm when she was a little girl, said it was about two feet long, or 60 cm, reddish in color, and its head and tail looked the same. This matches up with what other people have reported. In one clip, the show’s host tests the soil moisture content in the southern Gobi and is surprised that underneath the dry surface, the ground is actually quite moist. I’ll put a link to that one in the show notes.

There are actually earthworms that live in parts of the Gobi, including two species described in 2013. The earthworms don’t resemble reports of the Mongolian death worm, but if an earthworm can survive, other soft-bodied creatures can too. That’s assuming that the death worm is actually a worm and not a reptile or amphibian of some kind.

The best suggestion for what the death worm might be is an animal called the amphisbaenian. It’s sometimes also called the worm lizard, and while it’s not any kind of lizard, it is a reptile. Amphisbaenians live in many parts of the world, including most of South America and parts of North America, parts of Africa, southern Europe, and the Middle East. But since amphisbaenians live almost all of their lives underground, it’s very likely that species unknown to science live in other places. And much of Mongolia is extremely remote and probably not very well explored by scientists.

Amphisbaenians resemble snakes but they also resemble worms. The eyes are tiny and can be hard to spot, and the head and tail look very similar as a result. Many species are pink or reddish in color, although some are blue or other colors, including spotted, and many have scales that grow in a ringed pattern that make it look even more like an earthworm. But they’re not big animals, generally around six inches long, or 15 cm. Also, they’re slender like an earthworm, not as big around as someone’s arm. And they’re completely harmless to humans and large animals.

That doesn’t mean there can’t be a big amphisbaenian living in the remote parts of the Gobi, rarely seen even by the people who live there. Or, of course, the Mongolian death worm might be a completely different kind of animal, one totally unknown to science—maybe one that’s related to the amphisbaenian but radically different in appearance. Or it might be a mythical monster, although there are enough plausible-sounding witness sightings to think there’s something in the Gobi that looks like a big fat red horrible worm, even if it’s not actually dangerous.

What worries me, though, is that there don’t seem to be any sightings from recent times. Only old people report having seen a death worm back when they were young. Considering that so many Mongolian animals are endangered, it could be that the death worm is also declining in numbers so that fewer of them are around to be seen. Let’s hope Mongolian scientists are out there looking for the death worm and that they figure out what it is so it can be protected and studied in its natural habitat.

You can find Strange Animals Podcast online 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. We also have a Patreon at Patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes.

Thanks for listening!

Episode 155: Extreme Sexual Dimorphism

Many animals have differences between males and females, but some species have EXTREME differences!

The elephant seal male and female are very different sizes:

The huia female (bottom) had a beak very different from the male (top):

The eclectus parrot male (left) looks totally different from the female (right):

The triplewart seadevil, an anglerfish. On the drawing, you can see the male labeled in very small letters:

The female argonaut, also called the paper nautilus, makes a delicate see-through shell:

The male argonaut has no shell and is much smaller than the female (photo by Ryo Minemizu):

Lamprologus callipterus males are much larger than females:

The female green spoonworm. Male not pictured because he’s only a few millimeters long:

Show transcript:

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

I still have a lot of listener suggestions to get to, and don’t worry, I’ve got them all on the list. But I have other topics I want to cover first, like this week’s subject of extreme sexual dimorphism!

Sexual dimorphism is when the male of a species looks much different from the female. Not all animals show sexual dimorphism and most that do have relatively small differences. A lot of male birds are more brightly colored than females, for instance. The peacock is probably the most spectacular example, with the males having a brightly colored, iridescent fan of a tail to show off for the hens, which are mostly brown and gray, although they do have iridescent green neck feathers too.

But eclectus parrot males and females don’t even look like the same bird. The male is mostly green while the female is mostly red and purple. In fact, the first scientists to see them thought they were different species.

Males of some species are larger than females, while females of some species are larger than males. In the case of the elephant seal, the males are much larger than females. We talked about the northern elephant seal briefly last week, but only how big the male is. A male southern elephant seal can grow up to 20 feet long, or 6 meters, and can weigh up to 8,800 pounds, or 4,000 kg. The female usually only grows to about half that length and weight. The difference in this case is because males are fiercely territorial and fight each other, so a big male has an advantage over other males and reproduces more often. But the female doesn’t fight, so her smaller size means she doesn’t need to eat as much.

Another major size difference happens in spiders, but in this case the female is far larger than the male in many species. For instance, the body of the female western black widow spider, which lives throughout western North America, is about half an inch in length, or 16 mm, although of course that doesn’t count the legs. But the male is only half this length at most. Not only that, the male is skinny where the female has a large rounded abdomen, and the male is brown with pale markings, while the female is glossy black with a red hourglass marking on her abdomen. Female western widows can be dangerous since their venom is strong enough to kill many animals, although usually their bite is only painful and not deadly to humans and other mammals. But while the male does have venom, he can only inject a tiny amount with a bite so isn’t considered very dangerous in comparison.

The reason many male spiders are so much smaller than females is that the females of some species of spider will eat the male after or even during mating if she’s hungry. The smaller the male is, the less of a meal he would be and the less likely the female will bother to eat him. In the case of the western black widow, the male prefers to mate with females who are in good condition. In other words, he doesn’t want to spend time with a hungry female.

If you remember episode 139, about skunks and other stinky animals, we talked about the woodhoopoe and mentioned the bill differences between males and females. The male woodhoopoe has a longer, more curved bill than the female because males and females eat a slightly different diet of insects so they won’t compete for the same food sources.

But a bird called the huia took beak differences to the extreme. The huia lived in New Zealand, although it officially went extinct in 1907. It was a wattlebird, which gets its name from the brightly colored patch of skin on either side of the face, called wattles. In the case of the huia, the wattles were orange, while the feathers over most of the body were glossy black. It also had a strip of white at the tip of the long tail. The male’s beak was fairly long and pointy, although it also curved down slightly. But the female’s beak was much longer and more slender, curving downward in an arc.

The huia lived in forests in New Zealand, where it ate insects, especially beetle grubs that live in rotting logs. People used to think that a mated pair worked together to get at grubs and other insects. The male would use his shorter, stouter bill to break away pieces of rotting wood until the grub’s tunnel was exposed, and then the female would use her longer, more slender bill to fish the grub out of the tunnel. But actual observations of the huia before it went extinct indicate that it actually didn’t do this. Like the woodhoopoe, males and females preyed on different kinds of insects. The male did break open rotting wood with its beak in a way that’s very different from woodpeckers, though. Instead of hammering at the wood, it would wedge its bill into a crevice of the wood and open its beak, and the muscles and other structures it used to do so were so strong that it could easily break pieces of wood off. This action is known as gaping and other birds do it too, but the huia was probably better at it than any other bird known.

The huia went extinct partly due to habitat loss as European settlers cleared forests to make way for farming, and partly due to overhunting. Museums wanted stuffed huias for display, and the feathers were in demand to decorate hats. And as a result, we don’t have any huias left.

Sometimes the size difference between males and females reaches extreme proportions. We’ve talked about the anglerfish several times in different episodes, and it’s a good example. It’s a deep-sea fish with a bioluminescent lure on its head that it uses to attract prey. Different species grow to different sizes, but let’s just talk about one this time, the triplewart seadevil.

The triplewart seadevil is found throughout much of the world’s oceans, preferably in medium deep water but sometimes in shallow water and sometimes as deep as 13,000 feet, or 4000 meters. The female grows to about a foot long, or 30 cm. It’s black in color, although young fish are brown. Its body is covered with short spines and it has a lure on its head like other anglerfish. The lure is called an illicium, and it’s a highly modified dorsal spine that the fish can move around, including extending and retracting it. At the end of the illicium is a little bulb that contains bioluminescent bacteria. Whatever animals are attracted to the glowing illicium, the fish gulps down with its great big mouth.

But that’s the female triplewart seadevil. The male is tiny, only 30 mm long at the most. The male doesn’t have an illicium; instead, his jaws and teeth are specialized for one thing: to bite onto the female and never let go. When a male finds a female, he chooses a spot on her underside to latch on, and once he does, his mouth and one side of his body actually fuse to the female’s body. Their circulatory and digestive systems fuse too. Before the male finds a female, he has great big eyes, but once he fuses with a female his eyes degenerate because he no longer needs them. He’s fully dependent on the female, and in return she always has a male around to fertilize her eggs. But this attachment is actually pretty rare, because it’s hard for deep-sea fish to find each other.

Another sea creature where the females are much larger and very different from the males is the argonaut, or paper nautilus. The argonaut is an octopus that lives in the open ocean in tropical and subtropical waters. Instead of living on the bottom of the ocean, though, the paper nautilus lives near the surface, and while the female looks superficially similar to a nautilus, it’s only distantly related.

The female argonaut generally grows to about 4 inches long, or 10 cm, although the shell she makes can be up to a foot across, or 30 cm. In contrast, males are barely half an inch long, or 13 mm. The female’s eight arms are long because she uses them to catch prey, with two of her arms being larger than the others. She grabs small animals like sea slugs, crustaceans, and small fish and bites it with her beak, and like other octopuses she can inject venom at that point too. But the male has tiny little short arms except for one, which is slightly larger.

Like other cephalopods, the male uses one of his arms to transfer sperm to the female so she can fertilize her eggs. In most cephalopods that means an actual little packet of sperm that the male places inside the female’s mantle for her to use later. But in the argonaut, the male’s larger modified arm is called a hectocotylus, and it has little grooves that hold sperm. The male inserts the hectocotylus into the female’s mantle, then detaches it and leaves the arm inside her. Then he leaves and regrows the arm, as far as researchers know. We don’t actually know for sure since it’s never been observed, but octopuses do have the ability to regenerate lost arms. The female usually keeps the hectocotylus and sometimes ends up with several.

At that point the female creates a shell by secreting calcite from the tips of her two larger arms. The shell is delicate, papery, and white, and it resembles the shell of the ammonite, which we talked about in episode 86. The female lays her eggs inside the shell, then squeezes inside too, although she can come and go as she likes.

There’s still a lot we don’t know about the argonaut, but we know more than we used to. In the olden days people thought the female used her two larger arms as sails at the surface of the water. Eventually scientists figured out that was wrong, but they were still confused as to why there only seemed to be female argonauts. They didn’t know that the males were so small and so different, and in fact when early researchers found hectocotyluses inside the females, they assumed they were parasitic worms of some kind. Eventually they worked that part out too.

But still, for a very long time researchers thought the argonaut’s shell was just for protecting the eggs, but it turns out that the female uses the shell as a flotation device. She can control how much air the shell contains, which allows her to control how close to the surface she stays. In a 2010 study of argonauts rescued from fishing nets and released into a harbor, if the shell doesn’t contain enough air, the argonaut will jet to the surface and stick the top of its shell above the water. The shell has small openings at this point so air can get in, and once the argonaut decides it’s enough, she seals the holes by covering them with two of her arms. Then she jets downward again until she’s deep enough below the surface that the pressure compresses the air inside the shell and cancels out the weight of the shell. This means the argonaut won’t bob to the surface but she also won’t sink, and instead she can just swim normally by shooting water from her funnel like other octopuses.

A species of cichlid fish from Lake Tanganyika in Africa, Lamprologus callipterus, also differs in size due to a shell, but not like the argonaut. Instead, the male is much larger than the female. The male can be up to five inches long, or nearly 13 cm, while the female is less than two inches long, or 4 ½ cm. The females lay their eggs in shells, but not shells they make. The shells come from snails, so the male needs to be larger so he can pick up and carry a big empty shell. The female, though, still needs to be small enough to fit inside the shell.

A moth called the rusty tussock moth is also sexually dimorphic. Its caterpillar grows around 1 to 1.5 inches long, or 3 to 4 cm, with females being a little larger than male caterpillars but otherwise very similar. But after the caterpillars pupate, they’re much different. The male moth has orangey or reddish-brown wings and a wingspan of about 1.5 inches, or almost 4 cm. The female doesn’t have wings at all. She emerges from her cocoon and perches next to it, and releases pheromones that attract a male. After the female mates, she lays her eggs on her old cocoon and dies, as does the male.

Let’s finish up with an animal you may never have heard of, the green spoonworm. It’s a marine worm that lives throughout much of the Mediterranean and the northeastern Atlantic Ocean. It lives on the sea floor in shallow water, partly buried in gravel and sand. The female grows up to about six inches long, or 15 cm, and sort of looks like a mostly deflated dark green balloon, although it may also look kind of lumpy. It also has a feeding proboscis that it can extend several feet, or about a meter.

As a larva, the green spoonworm floats around in the water, but whether it becomes male or female depends on where it settles. If it lands on the seafloor it transforms into a female and starts secreting a toxin called bonellin. Bonellin is what gives the green spoonworm its dark green color. The bonellin is mostly concentrated in the feeding proboscis and allows the spoonworm to paralyze and kill the tiny animals it eats.

But if the larva happens to land on a female green spoonworm, contact with the bonellin causes it to become a male. And the male is only a few mm long, doesn’t produce bonellin, and can’t even survive on its own. The female sucks the male into her body through the feeding proboscis, but instead of digesting him, he lives inside her and fertilizes her eggs. In return she provides him with all the nutrients he needs. A female may have more than one male living inside her, making sure that her eggs will always be fertilized.

There are lots more animals that show extreme sexual dimorphism, of course, but that at least gives you an idea of how different animals evolve to fit different environmental pressures. Weird as they seem to us, to the animals in question, it’s just normal–and it’s our appearance and how we do things that would seem weird to them. Perspective is everything.

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you like the podcast and want to help us out, leave a rating and review on Apple Podcasts or whatever platform you listen on. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us and get twice-monthly bonus episodes.

Thanks for listening!

Episode 153: The White River Monster

Let’s start out the new year with a bona fide mystery animal, the White River Monster from Arkansas! Is it a real animal? If so, is it a known animal or something new to science? If it’s a known animal, what could it be? Lots of questions, maybe a few answers! Happy new year!

Further listening:

MonsterTalk

The not exactly useful picture supposedly of the White River Monster, taken in 1971:

A northern elephant seal, AKA Mr. Blobby:

A Florida manatee:

A bull shark:

Two bottlenose dolphins:

An alligator gar (below) and a human (above):

Alligator gar WEIRD FISH FACE:

Gulf sturgeon:

Show transcript:

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

If you’ve listened to the final episode of 2019 last week, you’ll remember it was about some mystery water animals of various kinds. Well, I’ve got another water mystery for you today to start off the new year, the White River monster. I heard about this one in a recent episode of MonsterTalk, which is a great podcast I recommend if you don’t already listen to it.

The White River is in North America, originating in the mountains in northwestern Arkansas and flowing from there through Missouri, then back into Arkansas where it joins the Mississippi River. In 1915 a man near the small town of Newport, in the central Ozarks region of Arkansas, saw an enormous animal with gray skin in the river.

A few other people saw it too, but it wasn’t until July of 1937 that things really heated up. The monster returned, and this time a lot of people saw it. News of it hit the local papers and spread throughout the country, and people started showing up to look for it. Some people came prepared to kill or catch it while others just wanted to see it.

Estimates of the monster’s size varied quite a bit. A man named Bramlett Bateman, who owned a lot of the farmland along that stretch of the river, was quoted in several newspaper articles. He described the monster as being the length of three cars in one article, but in another his estimate was smaller, only 12 feet long, or 3.7 m, and four or five feet wide, or 1.2 to 1.5 meters. But it doesn’t seem that he or anyone else got a really good look at it.

It was described by numerous people as being gray-skinned. Bateman said it had “the skin of an elephant…with the face of a catfish.” I dug into as many original newspaper articles as I could find without actually paying for access to them, and very few of them have a real description of the animal. The only description given in a New York Times article from July 23, 1937 is this:

“Half a dozen eye-witnesses…reported seeing a great creature rise to the surface at rare intervals, float silently for a few minutes and then submerge, making its presence known only by occasional snorts that bubbled up from the bottom.”

Another article quotes Bateman as saying he saw the monster “lolling on the surface of the water.”

Bateman decided he was going to blow the monster up with dynamite. What is it about people whose go-to solution to seeing an unidentified animal is to throw dynamite in the water? The local authorities said, uh no, you cannot just throw dynamite into the river, but other people brought machine guns and other weapons and patrolled the river looking for the monster. A plan to make a giant net and catch the monster petered out when people found out that making and deploying a net that big is expensive and difficult.

The monster was mostly reported in an eddy of the river that stretched for about a mile and was unusually deep, about 60 feet deep, or 18 meters. The river is about 75 feet wide at that point, or 23 meters. The Newport Chamber of Commerce hired a diver from Memphis named Charles B. Brown, who brought an eight-foot harpoon with him when he descended into the river. He didn’t find anything, but the tourists had fun.

Suggestions as to what the monster might be ranged from a sunken boat that sometimes bobbed briefly to the surface to a monstrous catfish. Many people were convinced it was a huge fish of some kind, especially an alligator gar.

Eventually sightings tapered off and the excitement died down until June of 1971, when it started being seen again. Again the size estimates were all over the place, with one witness saying it was the size of a boxcar, which would be about 50 feet long, or 15 meters, and 9 feet wide, or 2.8 meters. Another witness said it was only 20 feet long, or 6 meters. Some witnesses said it had smooth skin that looked like it was peeling all over, had a bone sticking out of its forehead, and it made sounds that one witness described as similar to both a horse’s neigh and a cow’s moo. On July 5, 1971, three-toed tracks 14 inches long, or 36 cm, were also found on an island together with crushed plants that showed a huge animal had come out of the water.

This time, at least, no one tried to dynamite or even net the monster. Instead, in 1973 Arkansas passed a law creating the White River Monster Refuge along that section of the river, to protect the monster. But no one has seen it since.

There is a photo of the monster taken in 1971, but it’s a blurry Polaroid that was reproduced in a newspaper and the original lost. The photo was taken by a man named Cloyce Warren, who was out fishing with two friends. Warren said it had “a spiny ridged backbone and [was] splashing all around.”

So what could the White River Monster be? Is it a misidentified known animal, a completely unknown animal, or just a hoax?

Obviously people are seeing something in that part of the White River. But it’s reportedly so big that if there was a population living anywhere in the river, it would be spotted all the time. So maybe it’s an animal that only sometimes strays into the White River and actually lives in the much larger Mississippi River—or even in the Gulf of Mexico, where it sometimes swims upriver.

Cryptozoologists and other interested people have made suggestions over the years. One suggestion is that it’s an elephant seal. The northern elephant seal is an enormous animal, although it’s nowhere near 50 feet long. The male is much larger than the female, up to 16 feet long, or 4.8 meters, and bulky with blubber that keeps it warm when diving deeply for food in the Pacific Ocean where it lives.

But wait, the Pacific Ocean? You mean it doesn’t live in the Gulf of Mexico?

Nope, the endangered elephant seal only lives in the Pacific. And the Pacific Ocean is separated from the Gulf of Mexico by a whole lot of the North American continent.

A man named Joe Nickell, who’s a paranormal investigator and who was interviewed on MonsterTalk episode 204, has suggested the White River Monster is a manatee—specifically the Florida manatee, which is a subspecies of West Indian manatee. In the winter it mostly lives around Florida but in summer many individuals travel widely. It’s sometimes found as far north as Massachusetts along the Atlantic coast, and as far west as Texas in the Gulf of Mexico.

The manatee is large, up to 15 feet long, or 4.6 meters, with females being somewhat larger than males. Its skin is gray but since it moves slowly, it can look mottled in color due to algae growing on its skin, and it sometimes also has barnacles stuck to it the way some whales do. It has a pair of front flippers with three or four toenails, no hind legs, and a paddle-like tail. It eats plants and only plants, and is completely harmless to humans, fish, and other animals. Also because it moves slowly and spends a lot of time at the surface, since it’s a mammal and has to breathe air, it’s vulnerable to being injured by boats.

In the 1970s there were only a few hundred manatees alive and it nearly went extinct. It was listed as an endangered species and after a lot of effort by a lot of different conservation groups, it’s now only considered threatened. So while people might recognize a manatee these days, back in the 1970s it was practically unknown everywhere except southern Florida since it was so rare. And in the decades before 1971, people didn’t travel as much and didn’t know much about increasingly rare animals that didn’t live in their particular part of the world.

In other words, it’s completely possible that people from Arkansas would see a manatee in 1915, 1937, and 1971 and not know what it was. But could a manatee really travel that far from the ocean and survive?

The Mississippi River empties into the Gulf of Mexico in Louisiana in the United States. Texas is to the west of Louisiana, then Mississippi, Alabama, and Florida to the east. In other words, it’s well within the known range of the Florida manatee. Manatees are known to sometimes travel up the Mississippi. This happened most recently in October of 2016 when a manatee traveled as far as Memphis, Tennessee before it was found dead in a small lake connected to the river. That’s a distance of 720 miles, or 1,158 km, and that was with wildlife officials trying to capture it to return it to the Gulf. That same year a manatee also traveled as far as Rhode Island along the Atlantic coast. Memphis is actually much farther up the Mississippi than the White River is, so if the manatee had branched off into the White River it might have led to new sightings of the White River Monster.

The manatee can live in fresh water perfectly well. One species, the Amazonian manatee, is a fully freshwater animal that never leaves the South American rivers where it lives. But despite its size, the manatee doesn’t have a lot of blubber or fat to keep it warm. The farther away it travels from warm water, the more likely it is to die of cold.

But while an errant manatee might explain some White River Monster sightings, it doesn’t fit with all of them. Other animals from the Gulf of Mexico sometimes find their way up the Mississippi too. It’s a huge river, and since an ocean animal doesn’t understand what a river is, it doesn’t know it’s never going to reach the ocean again unless it turns around. Most marine animals can’t survive for long in fresh water, but some animals, like the manatee, can tolerate fresh water much better. That’s also the case for the bull shark.

In 1937, the same year the White River Monster was spotted for the second time, a five-foot bull shark, or 1.5 meters, was caught in Illinois, which is even farther upstream from the Gulf of Mexico than Tennessee and Arkansas. Bull sharks live throughout much of the world’s oceans in warmer water near coasts and are often found in rivers and lakes, although they don’t live as long in fresh water as they do in salt water. The largest bull shark ever measured was 13 feet long, or 4 meters, so a large one is about the size of a manatee.

Occasionally a dolphin travels up the Mississippi River, but marine dolphins can’t survive for long in fresh water and will die soon if they can’t make their way back to the ocean. A dolphin in fresh water starts to develop skin lesions and then the skin begins to peel, leading to bacterial infection and death. Remember that some witnesses in 1971 described the White River Monster as a gray animal with peeling skin.

Nine different species of dolphin and many species of whale live in the Gulf of Mexico. Of those, only the bottlenose dolphin lives close to the coast and is usually the species that accidentally travels into fresh water and can’t find its way out. The bottlenose dolphin isn’t any larger than the manatee, up to about 13 feet long, or 4 meters.

1971 was an active hurricane year, including the category 5 Hurricane Edith that killed 37 people in mid-September. Marine animals that can travel quickly, like dolphins and sharks, will flee to calmer waters when a hurricane approaches, and while that usually means out to sea, it wouldn’t be out of the question for a frightened dolphin or other large marine animal to make its way into the Mississippi by accident ahead of a hurricane, especially a hurricane as big as Edith.

Another possible identity for the White River Monster is one that was suggested in 1937, the alligator gar. It’s a freshwater fish that lives throughout the Mississippi River and other rivers and lakes in the southern United States and parts of northern Mexico. The alligator gar gets its name because of its toothy jaws, which do resemble an alligator’s, and it can grow up to ten feet long, or 3 meters. It’s a really weird fish and eventually I’ll probably do a full episode on it and its relatives, just as I have a full episode planned about the manatee. It has gills like other fish, but it can also breathe air through its swim bladder, which is lined with lots of blood vessels that absorb oxygen. Every so often an alligator gar will come to the surface and gulp air to replenish the oxygen in its swim bladder, so it would be seen at the surface briefly but periodically as was described by many witnesses. This is also the case for the manatee and dolphin, who breathe air.

The alligator gar is an ambush predator, which means it waits in the water without moving much at all until an animal approaches. Then it shoots forward and grabs it. It mostly eats small fish, invertebrates of various kinds, and waterfowl like ducks.

The final possibility of the White River Monster’s identity is the gulf sturgeon. It’s a subspecies of the Atlantic sturgeon that lives in the Gulf of Mexico, although it’s also known from various rivers in the southeastern United States. The reason it’s found in rivers is that the gulf sturgeon is anadromous [a-NADro-mus], the term for a fish that migrates from the ocean into fresh water to spawn. The salmon is the most famous anadromous fish, which fights its way upriver to spawn and then die. In the case of the gulf sturgeon, it hatches in fresh water and lives there for the first two years or so of its life before making its way downstream to the ocean. Then it returns to freshwater to spawn every spring, usually the same river where it was hatched, and goes back to the ocean in autumn.

The gulf sturgeon fits a lot of the descriptions of the White River Monster sightings. It’s covered with five rows of scutes that project from the back and sides in a sort of low sawtooth pattern, which fits the “spiny ridged backbone” that Cloyce Warren reported seeing in 1971, and its elongated snout has sensory barbels like a catfish, which matches Bramlett Bateman’s 1937 description of the monster having the face of a catfish. It’s gray, gray-green, or brownish in color with a lighter belly, and it can grow up to 15 feet long, or 4.5 meters, although most are about half that length.

The gulf sturgeon usually migrates in groups, but occasionally one can get separated from its group and find its way into a stretch of water by itself. It also doesn’t eat much during the summer when it’s in freshwater. In the winter it lives just off the coast in shallow water, where it’s a bottom feeder. It sucks up invertebrates from the sea floor, feeling for them with their barbels. It gains lots of weight during the winter and then loses it all in the summer. Sturgeons do sometimes jump out of the water, especially in summer–as much as fix feet out of the water. No one’s sure why. Also during the summer, the sturgeon makes a sound like a creaky hinge.

I think it’s probable that the White River Monster sightings are of more than one type of animal, and while we can make an educated guess as to which animals might have been spotted and misidentified, we can’t know for sure. So while at least some of the sightings may have been of a manatee or a gulf sturgeon or another of the animals we talked about today, there’s also the possibility that something else occasionally swims up the Mississippi from the Gulf and into the White River. Hopefully, next time the White River Monster appears, someone gets a really good look at it and some good pictures so we know for sure.

This is what a sturgeon sounds like, by the way:

[sturgeon creaky sound]

You can find Strange Animals Podcast online 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. We also have a Patreon if you’d like to support us and get twice-monthly bonus episodes.

Thanks for listening!

Episode 152: The Freshwater Seahorse and Other Mystery Water Animals

This week let’s look at some (mostly) smaller mystery animals associated with water! Thanks to Richard J., Janice, and Simon for the suggestions!

Further reading:

What Was the Montauk Monster?

The black-striped pipefish. Also, that guy has REALLY BIG FINGERTIPS:

The Pondicherry shark, not looking very happy:

A ratfish. What BIG EYES you have!

The hoodwinker sunfish, weird and serene:

The Montauk monster, looking very sad and dead:

Show transcript:

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

Let’s finish off the year with an episode about a few mystery animals, specifically a few mystery animals associated with water. Thanks to Richard, Janice, and Simon for the suggestions!

We’ll start off with a mystery suggested by Richard J, but not the Richard J. who is my brother. A different Richard J. Apparently half the people who listen to my podcast are named Richard, and that’s just fine with me.

Richard wanted to know if there are there such things as freshwater seahorses. We’ve talked about seahorses before in episode 130, but seahorses are definitely marine animals. That means they only live in the ocean. But Richard said he’d heard about a population of seahorses native to Lake Titicaca in Bolivia, which is in South America. I put it on my suggestions list, but Richard was on the case. He sent me a link to an article looking into the mystery, which got me really intrigued, so I bumped it to the top of my list. Because I can do that. It’s my podcast.

Freshwater seahorses are supposedly known in the Mekong River and in Lake Titicaca, and sometimes you’ll see reference to the scientific name Hippocampus titicacanesis. But that’s actually not an official scientific name. There’s no type specimen and no published description. Hippocampus is the generic name for many seahorse species, but like I said, they’re all marine animals and there’s no evidence that any live in freshwater at all. Another scientific name supposedly used for the Mekong freshwater seahorse is Hippocampus aimei, but that’s a rejected name for a seahorse named Hippocampus spinosissimus, the hedgehog seahorse. It does live in parts of the Indo-Pacific Ocean, including around Australia, especially in coral reefs, and sometimes in the brackish water at the Mekong River’s mouth, but not in fresh water.

On the other hand, there’s no reason why a seahorse couldn’t adapt to freshwater living. A few of its close relatives have. There are a few species of freshwater pipefish, and in the world of aquarium enthusiasts they are actually sometimes called freshwater seahorses. The pipefish looks like a seahorse that’s been straightened out, and most of them are marine animals. But some have adapted to freshwater habitats.

This includes the black-striped pipefish, which is found off the coasts of much of Europe but which also lives in the mouths of rivers. At some point it got introduced into the Volga River and liked it so much it has started to expand into other freshwater lakes and rivers in Europe.

The pipefish is closely related to the seahorse, but while it does have bony plates like a seahorse, it’s a flexible fish. It swims more like a snake than a fish, and it can anchor itself to vegetation just like a seahorse by wrapping its tail around it. It mostly eats tiny crustaceans and newly hatched fish, since it swallows its food whole. It usually hides in vegetation until a tiny animal swims near, and then it uses its tube-shaped mouth like a straw to suck in water along with the animal. Just like the seahorse, the male pipefish has a brooding pouch and takes care of the eggs after the female deposits them in his pouch.

So where did the rumor that seahorses live in the Mekong come from? The Mekong is a river in southeast Asia that runs through at least six countries, including China, Thailand, Cambodia, and Vietnam. Parts of it are hard to navigate due to waterfalls and rapids, but it’s used as a shipping route and there are lots of people who live along the river. Like all rivers, it’s home to many interesting animals, including a type of giant softshell turtle that can grow up to six feet long, or 1.8 meters, a type of otter, a bunch of enormous fish, including three species of catfish that can grow up to almost ten feet long, or 3 meters, and a giant freshwater stingray that can grow up to 16 feet long, or 5 meters, and of course lots more animals that aren’t as big or as impressive, but which are still important to the river’s biodiversity. But there’s no evidence of seahorses anywhere throughout the Mekong’s 2700 mile length, or 4,350 km.

But there is a hint about where the rumor of a Mekong seahorse could have come from. One researcher named Heiko Bleher chased down the type specimens of the supposed Mekong seahorse in a Paris museum, which were collected in the early 20th century by a man named Roule. Roule got them in Laos from a fisherman who had nailed the dried seahorses to his fishing hut. The fisherman told Roule the seahorses were from the Mekong, but when they were further studied in 1999 Roule’s specimens were discovered to actually be specimens of Hippocampus spinosissimus and Hippocampus barbouri. Both are marine fish but do sometimes live in brackish water at the mouth of the Mekong. So the fisherman wasn’t lying, but Roule misunderstood what he meant.

As for the freshwater seahorse supposedly found in Lake Titicaca, that one’s less easy to explain. Titicaca is a freshwater lake in South America, specifically in the Andes Mountains on the border of Bolivia and Peru. It’s the largest lake in South America and is far, far above the ocean’s surface—12,507 feet above sea level, in fact, or 3,812 meters. It’s also extremely deep, 932 feet deep in some areas, or 284 meters. It’s home to many species of animal that live nowhere else in the world. Why couldn’t it be home to a freshwater seahorse too?

Titicaca was formed when a massive earthquake some 25 million years ago essentially shoved two mountains apart, leaving a gap—although technically it’s two gaps connected with a narrow strait. Over the centuries rainwater, snowmelt, and streams gradually filled the gaps, and these days five rivers and many streams from higher in the mountains feed water into the lake. Water leaves the lake by the River Desaguadero and flows into two other lakes, but those lakes aren’t connected to the sea. Sometimes they dry up completely. So Titicaca isn’t connected to the ocean and never was, and even if it was, seahorses are weak swimmers and would never be able to venture up a river 12,000 feet above sea level. Some 90% of all fish in the lake are found nowhere else in the world. There’s just simply no way a population of seahorses could have gotten into the lake in the first place, even if they could survive there.

That doesn’t mean there aren’t any freshwater seahorses out there ready to be discovered, of course. But I don’t think you’re going to find any in Lake Titicaca. And I have no idea how the rumor got started that any live there.

From a tiny seahorse let’s move on to a small shark, another topic suggested by Richard J. The Pondicherry shark grows to about 3.3 feet, or 1 meter, and once lived throughout the Indo-Pacific, especially in coastal waters. It’s considered critically endangered, but it’s so rare these days that we hardly know anything about it except that it’s harmless to humans, eats small fish and other small animals, and was once common. But until the mid-2010s, scientists were starting to worry it was already extinct. Then in 2016 two different Pondicherry sharks were photographed in two different places—and not where anyone had expected to find it. Some tourists took a photo of one in a river called the Menik and a freshwater fish survey camera caught a photo of one in the Kumbuk River. Both rivers are in Sri Lanka. Since then researchers have spotted a few more. The shark is protected, and hopefully the excitement around the shark’s rediscovery has helped people in the area learn about it so they know not to bother it. Some sharks tolerate fresh water and brackish water quite well, so it’s not surprising that the Pondicherry shark has moved into the rivers where it has less competition from commercial fishing boats.

Our next water mystery is actually not really a mystery, just a really strange-looking fish related to sharks. This one was suggested by my aunt Janice who doesn’t actually listen to the podcast but who likes to send me links to strange animal articles that she comes across on the internet. This one is called Chimaera Monstrosa, sometimes called the rat fish.

The rat fish mostly lives in the deep sea, although it’s sometimes seen in shallower water, and can grow up to 5 feet long, or 1.5 meters. It’s mostly brown but has white markings. Its body looks more or less like a regular plump shark-like fish, but it has great big round green eyes, relatively long pectoral fins, and a very long tail that tapers to a point. The tail gives it its common name, since it kind of resembles a rat’s tail. It eats whatever it can catch on the ocean floor, including crustaceans and echinoderms.

Ratfish, and other chimaeriformes, are most closely related to sharks, and like sharks they have skeletons that are made of cartilage instead of bone. Since they’re rarely seen and look really weird, every so often someone catches one and posts about it online, and then my aunt sends me a link. They are really interesting fish, though.

Simon also sent me an article about an interesting fish a while back, the hoodwinker sunfish. We talked about the sunfish, or mola mola, in episode 96. The hoodwinker sunfish, or mola tecta, was only discovered in 2017 despite its large size. So far it’s known to live in the South Pacific around New Zealand, Australia, South Africa, and Chile, but only off the southernmost parts of those countries. But in early 2019 one washed up in Southern California.

The mystery sunfish was measured at almost 7 feet long, or 2.1 meters. An intern at the University of California at Santa Barbara found it, but didn’t know what it was. But once photos of the fish were posted online, two experts from Australia recognized it immediately—but because it showed up so far out of its known range, they were cautious about IDing it from just a photo. That’s despite the fact that one of the experts, Marianne Nyegaard, was actually the person who named the species. She asked for samples and more photos, and when she got the results, it really was a hoodwinker sunfish. But what was it doing in the warm waters of the northern Pacific instead of the cold southern waters? No one knows except the sunfish.

Let’s finish with another mystery animal you may have heard of. On July 12 or 13, 2008, depending on which source you consult, three friends visited Ditch Plains Beach, two miles away from the little town of Montauk in New York state in eastern North America. It was a hot day and the beach was crowded, and when the three noticed people gathered around something, they went to look too. There they saw a weird dead animal that had obviously washed ashore. One of the three took a picture of it, which appeared in the local papers and then the local TV news along with an interview with the three. From there it went viral and was dubbed the Montauk monster.

The monster was about the size of a cat, but with shorter legs and a chunkier body, and a relatively short tail. It didn’t have much hair but it did have sharp teeth, and the front part of its skull was exposed so that it almost looked like it had a beak. Its front paws were elongated with long fingers, almost like little hands.

So what was the monster? People all over the world made guesses, everything from a sea turtle without a shell to a diseased dog or just a hoax. Some people thought it was a mutant animal that had been created in a lab on one of the nearby islands, escaped, and died trying to swim to the mainland.

But while no one knows what happened to the animal’s body, scientists have studied the photo and determined that it was probably a dead raccoon that had been washed into the ocean. The waves had tumbled the animal’s body around through the sand long enough to rub off most of its remaining fur and some of its facial features, and then it washed ashore during the next high tide. It was also somewhat bloated due to gases building up inside during decomposition. It’s the animal’s teeth and paws that made the identification possible, since both match a raccoon’s exactly. Remember that raccoons have clever front paws that help them open locking trash bins, as we learned in episode 138.

So the Montauk monster isn’t actually a mystery, except what happened to it, but don’t be discouraged. There are still lots of genuinely mysterious animals in the ocean, from misplaced sunfish to creatures no one has ever seen yet. Maybe you’ll be the one to discover them.

You can find Strange Animals Podcast online 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. We also have a Patreon at Patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes.

Thanks for listening!

Episode 151: Fossils with other fossils inside

Thanks to Pranav who suggested this week’s amazing topic, animals that fossilized with the remains of their last meal inside!

Indrasaurus with a lizard inside. Yum!

Baryonyx:

Rhamphorhynchus (left, with long wing bones) and its Fish of Doom (right):

The fish within a fish fossil is a reminder to chew your food instead of swallowing it alive where it can kill you:

The turducken of fossils! A snake with a lizard inside with a bug inside!

Show transcript:

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

This week we have a listener suggestion from Pranav, who has sent me so many amazing suggestions that he has his own page on the ideas spreadsheet. When he emailed me about this one, he just suggested cool fossils, but the links he provided had a really interesting theme that I never would have thought about on my own. This week we’re going to learn about some fossil animals that have fossils of their last meal inside them!

We’ll start with a recent discovery of a new microraptor species, Indrasaurus wangi, which lived about 120 million years ago. It was an interesting animal to start with, because it had arms that were very similar to bird wings, although with claws, but its hind legs also had long feathers that made it almost like a four-winged animal. It was found in 2003 in northeastern China, but when researchers were studying it in 2019 they found something amazing. Not only did it have an entire lizard skeleton where its stomach once was, showing us that it swallowed its prey whole, the lizard itself was a species new to science.

We know what else Indrasaurus ate because more Indrasaurus fossils have been found in the area, many of them so well preserved that its fossilized stomach contents have been preserved too. It ate mammals, birds, lizards, and fish—basically anything it could catch.

Another species that was similar to Indrasaurus, called Anchiornis, also called a four-winged bird-like dinosaur, was found with what appears to be a gastric pellet in its throat. The pellet contains the bones of more than one lizard and was probably ready to be horked up the way many carnivorous birds still regurgitate pellets made up of the indigestible parts of their prey, like bones, scales, and fur.

The fossilized remains of food inside a fossilized organism has a term, of course. It’s called a consumulite. It’s a type of bromalite, which is a broader term for any food or former food found in a fossilized organism’s digestive tract. The term bromalite also includes coprolites, which are fossilized poops.

Naturally, it requires a high degree of preservation for consumulites to form, and a high degree of skill to reveal the often tiny and delicate preserved details. And consumulites are important because they let us know exactly what the animal was eating.

Consumulites aren’t limited to prey animals, either. A small armored dinosaur, a type of ankylosaur, called Kunbarrasaurus, which lived around 115 million years ago in what is now Australia, was a herbivore. The type specimen of the species, which was described in 2015, was incredibly well preserved—almost the entire skeleton, most of its body armor, and the contents of its stomach. Paleontologists can determine not just what kinds of plants it had eaten—which include ferns and seeds—but how it was processing its food. Most herbivorous dinosaurs swallowed leaves and other plant parts whole, then crushed the food in a powerful gizzard or gizzard-like organ along with rocks or grit. The rocks helped break up the plant material, and we have lots of these rocks associated with fossilized dinosaurs. The rocks are called gastroliths and are usually worn smooth. But Kunbarrasaurus didn’t have any gastroliths, and the plant material was so well preserved that researchers could see the cut ends of the plants where Kunbarrasaurus had bitten them. And all the pieces were small. Kunbarrasaurus therefore probably chewed its food, which meant it also probably had lips and cheeks of some kind to help keep the food in its mouth while it was chewing.

Another example of an animal with a consumulite that helped solve a mystery about its diet is Baryonyx. Baryonyx is a type of spinosaurid, a theropod dinosaur that grew at least 33 feet long, or 10 meters. It was discovered in 1983 in Surrey, England, and was described in 1986. It lived around 125 million years ago. It walked on its hind legs and probably used its arms to tear its prey into bite-sized pieces, because its first finger had a huge claw 12 inches long, or 31 cm.

But its skull was the real puzzle. Most theropods are meat-eaters, although a few evolved to eat plants. But Baryonyx had a long, relatively slender snout with a lot of close-growing teeth, and a sort of bulb at the end of its snout called a rosette. It looks more like the skull of a crocodilian called a gharial than a theropod. But as far as anyone knew when Baryonyx was discovered, there were no fish-eating theropods.

Until 1997, that is, when paleontologists studying Baryonyx spotted some overlooked details. In addition to a gastrolith in its belly area, they found some fish scales and teeth that showed evidence of being damaged by digestive acids. It probably hunted by wading through shallow water like a heron, catching fish and other animals with its long toothy snout.

It’s not just dinosaurs that are found with consumulites. Animals of all kinds eat all the time, so as long as the conditions are right to fossilize the remains of an animal, there’s a chance that whatever food was in the digestive tract might fossilize too. For instance, the same part of China that has yielded amazingly well preserved feathered dinosaurs has also produced other animals—including a carnivorous mammal called Repenomamus that grew more than three feet long, or one meter. I think we’ve talked about Repenomamus before, because we have evidence that it actually ate dinosaurs—at least baby ones, or it might have scavenged already dead dinosaurs. Either way, it lived around 125 million years ago and was shaped sort of like a badger with a long tail, although it wasn’t related at all to badgers or any other modern mammal. It probably laid eggs like monotremes still do. The reason we know what Repenomamus ate is because one specimen was found with pieces of a young Psittacosaurus in its stomach.

In at least one case it’s hard to tell which animal should be considered the eater and which should be considered the eaten. A fossil slab found in Southern Germany and described in 2012 contains a Rhamphorhynchus associated with two different fish.

Rhamphorhynchus lived around 150 million years ago and was a type of pterosaur with a long tail. Its wingspan was about six feet across, or 1.8 meters. It mostly ate fish, which it probably caught not by flying down to grab fish out of the water, like eagles do, but by floating like a goose and diving for fish. It had large feet and short legs, which would have helped it take off from the water just like a goose.

A fish that lived at the same time as Rhamphorhynchus was called Aspidorhynchus, and it grew up to two feet long, or 60 cm. It had long jaws filled with teeth, with the upper jaw, or rostrum, extending into a pointy spike.

In the fossil found in Germany, a Rhamphorhynchus has a small fish in its throat that it had probably just caught. While it was still swallowing it, an Aspidorhynchus fish attacked! But things obviously went wrong for everyone involved. Researchers suggest that the fish’s rostrum cut right through the flying membrane of Rhamphorhynchus’s left wing. The fish bit down but its teeth became tangled in the tissue. It started thrashing to free itself and Rhamphorhynchus was thrashing around too trying to get away, which only got them more tangled up together. The fish dived, drowning Rhamphorhynchus, and the weight of its body dragged Aspidorhynchus into deep water where there wasn’t enough oxygen for it to survive. It died too, and its heavier body lay partially across Rhamphorhynchus, holding it down so it wouldn’t drift away. The fossil shows Rhamphorynchus, Aspidorhynchus, and the tiny fish that Rhamphorhynchus never did get to finish swallowing.

Another fish, Cimolichthys, lived around 75 or 80 million years ago and grew a little over six feet long, or two meters. Its body was heavily armored by large scutes and it had several rows of teeth. It may have been related to modern salmon. It lived in what is now North America and Europe, and ate fish and squid. We know it ate fish and squid because, of course, we have the remains of various last meals found with preserved fossil Cimolichthys. For instance, one specimen was found with the internal shell of a cephalopod lodged in its throat. Researchers suspect the fish had tried to swallow a Tusoteuthis that was too big to fit down its throat. The Tusoteuthis got stuck and blocked the flow of water over the fish’s gills, basically drowning it. Tusoteuthis, by the way, could possibly grow up to 36 feet long, or 11 meters, although that depends on whether it had long feeding tentacles like modern squid or not. If it didn’t have long feeding tentacles, it was probably only about 19 feet long, or 6 meters, which is pretty darn big anyway. I wouldn’t want to have to swallow that thing whole. Not even if it was deep-fried first.

Another fish called Xiphactinus, which grew up to 20 feet long, or 6 meters, lived in the late Cretaceous period. It died out at the same time as the non-avian dinosaurs. It had massive fangs and was a terrifying predator, but sometimes that backfires. The fossil of a 13 foot, or 4 meter, Xiphactinus was found with a 6 foot long, or 1.8 meter, fish called Gillicus inside it. Paleontologists think Xiphactinus swallowed its prey whole, which thrashed around so much inside it that it ruptured an organ and killed the predator fish. Both fish sank to the bottom of the shallow Western Interior Seaway in North America until it was discovered in 1952.

Let’s finish with two even more incredible fossils. In 2008 paleontologists found a fossilized freshwater shark they dated to 250 million years ago. Right before it died, it had eaten two animals called temnospondyls. Temnospondyls were common animals, with many species found throughout the world, and researchers still aren’t sure if they were the ancestors of modern amphibians or a similar type of animal that died out without any descendants. One of the temnospondyls that the shark ate had the well digested remains of a spiny fish in its stomach.

But a few years later researchers in Germany found something even better. It’s a fossilized snake called a Palaeopython, related to boas. It was about three feet long, or one meter, and was still young. If it had lived to grow up, it would have doubled in size. It lived in trees but also hunted along the edges of rivers and lakes. About 48 million years ago, this particular snake caught a lizard that’s related to modern basilisk lizards. It swallowed the lizard headfirst. But then the snake died, possibly asphyxiated by a cloud of carbon dioxide from the volcanic lake nearby. We have a lot of incredibly detailed fossils from that lake, known as the Messel Pit.

Researchers aren’t sure how the snake made it into the lake. Maybe it was already in the shallow water when it died, or on the bank, and a wave washed it into the water. Maybe the wave was actually what killed the snake, washing it into the lake where it drowned. However it died, it sank into deep water and was covered in sediment that preserved it. Then, 48 million years later, paleontologists found it.

When the fossil was cleaned and prepared for study, researchers found that the lizard was preserved inside it. But there was another surprise inside the lizard! Right before it had been eaten by the snake, the lizard had eaten an insect. And the insect was so well preserved that researchers could tell it had an iridescent exoskeleton.

If I was fossilized right now, paleontologists from the far future would find a lot of chocolate in my stomach. Happy holidays to everyone, whatever your reason for celebrating at this time of year!

You can find Strange Animals Podcast online 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. We also have a Patreon if you’d like to support us and get twice-monthly bonus episodes.

Thanks for listening!

Episode 140: Rains of Fish and Frogs (and other things)

We’re starting off October (you know, MONSTER MONTH) with accounts of animals that fall from the sky like rain, mostly fish and frogs! Is this a real thing that actually happens, and if so, what causes it?

Further reading:

Raining Frogs

Recent observations of “mystery star jelly” in Scotland appear to confirm one origin as spawn jelly from frogs or toads

Not a real photo of an octopus falling in a storm:

This photo is probably real, two shrimp/prawns on a windshield in the same storm as above (in 2018):

A photo of people picking up fish in the street but I have no idea where it was taken:

An arctic lamprey found in someone’s yard:

Some of the stuff called star jelly, star rot, or star snot:

A walking catfish:

Show transcript:

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

It’s finally October, and that means monsters and other spooky stuff! I have lots of fun episodes planned this month, but first, an important announcement!

A few weeks ago I got a message from someone on Podbean, and I feel terrible because I can’t reply or even see the whole message or who it’s from! Podbean does not like me. I get an email with the first couple of lines of the message but when I click through and log in to Podbean to see the whole message and respond, Podbean goes, “Message? What message? You don’t have any messages.” So please, person who messaged me with a suggestion I can’t see, I’d love it if you email me at strangeanimalspodcast@gmail.com! And if anyone else has ever messaged me somewhere but never received a reply, email is the best way to get hold of me. I always reply, so if you don’t get an answer it means I never saw your message and you should totally send it again. Thanks!

So, back to the October fun! Let’s start off the month right with a strange phenomenon that’s been reported for untold centuries all over the world. Do fish and frogs and other animals actually sometimes fall from the sky like rain?

It seems pretty certain that while this is a rare event, and not all reports are of animals that actually fell from the sky, it does sometimes happen. In fact, lots of weird stuff falls from the sky from time to time. For instance, after a heavy rain over Punta Gorda, Florida at the end of August 1969, the streets were full of golf balls, dozens of them if not hundreds. But there wasn’t a golf course near the town.

Sometimes colored rain falls instead of ordinary clear water. This happens because raindrops form around tiny specks of dust or pollen in the air. When the dust is colored, the rain will be too. Red rains come from dust blown into the atmosphere from the Sahara while yellow rain results from dust from the Gobi Desert. Volcanic eruptions, soot, and other pollutants in the air can cause black rain. And a red rain that fell in Kerala, India in July 2001 was analyzed and the color found to be due to fungal spores. Snow is occasionally colored too, just like rain.

But sometimes frogs, fish, or other small animals do apparently fall from the sky, with or without rain. Here’s a typical report of a rain of frogs. It comes from the book The Unexplained by zoologist Karl Shuker, whose honesty and scholarship I trust. Not only that, it’s something that happened to his own grandmother, Gertrude Timmins. In 1902, Gertrude was only eight years old. She and her mother were walking across a field in the West Midlands in England when it started to rain. They opened their umbrellas, but a moment later Gertrude noticed that amid the regular pattering of rain on an umbrella there were some heavier thumps. Then she noticed that the thumps were caused by small frogs falling onto her umbrella and bouncing off onto the ground. Gertrude was frightened at first, naturally, because that’s just a weird thing to happen to anyone. But her mother told her not to be scared, it was just a rain of frogs.

Remember, Gertrude and her mother were walking across a field. There weren’t any trees or buildings around that the frogs might have fallen from. So where did they come from?

The main hypothesis is that the animals are picked up by a water spout or small tornado and carried on the wind until they’re dropped elsewhere, miles away. When I was a kid I thought this was a dumb suggestion. If a dissipating water spout dropped everything it had picked up out of a pond, why do people just report one kind of frog falling from the sky or one kind of fish? Where’s the algae, water plants, turtles, mud, and other stuff presumably also picked up and carried out of a pond?

The answer may be pretty simple. When the wind velocity is high, the tornado or water spout can carry heavy objects, but as the wind slows and loses energy, it starts to drop the heaviest items. But the wind is still moving, so as it moves across the land and slowly loses more and more energy, it drops the heaviest items first, then the next heaviest items, then the next heaviest, and so on.

It might not even be a tornado or water spout. A powerful updraft, which is often associated with storms, can lift light items like sticks, leaves, and pool toys and drop them miles away. Small frogs often weigh no more than a penny does and during breeding season can be incredibly common in a small area, hopping everywhere. It’s reasonable to assume that sometimes these little frogs get lifted from one area by a strong updraft and dropped elsewhere, astonishing anyone who happens to see it. If you doubt the strength of an updraft, keep in mind that storms can also generate downdrafts and they can be so powerful they destroy or uproot trees.

No one has witnessed frogs or other animals get sucked up into the air and dropped elsewhere, so we don’t know if it actually happens this way. But the animals are obviously getting into the air somehow.

Frogs aren’t the only animals witnessed to fall from the sky. Fish are actually probably the most common animals that fall with rain. It doesn’t even have to be raining.

On October 23, 1947 fish fell over Marksville, Louisiana in the United States. A biologist was having breakfast with his wife in a local restaurant when the server said that fish were falling from the sky. Naturally he went to look. He identified the fish as several different freshwater species common in the area, including two species of sunfish, a type of bass, and a few others, all ranging from 2 to 9 inches long, or 5 to 23 cm. It was a foggy but calm morning with no reports of tornados or strong winds in the area.

It’s possible that a small waterspout formed over one of the many nearby lakes, sucked up whatever fish happened to be in the wrong place at the wrong time, and deposited them a few miles away. Waterspouts form the same way tornados do except that it happens over water. The inside of a waterspout, like the inside of a tornado, is a low-pressure tunnel inside a high-pressure cone of air. It acts like a vacuum cleaner, sucking up water as it moves, and anything that’s in the water near the surface gets sucked up too.

There are two types of waterspouts. Tornadic waterspouts are tornados that happen to touch down over water instead of land. They can be dangerous and are usually reported in the local news and weather if they’re spotted. But fair-weather waterspouts aren’t associated with storms, although they do form ahead of developing storm systems. They’re typically smaller, much less dangerous, and much less likely to be reported to the news. So it’s possible that the 1947 fish fall was the result of a fair-weather waterspout.

This phenomenon isn’t something that used to happen in the olden days and doesn’t happen now. In June of 2009, there were tadpole rains in parts of Japan on two different days in slightly different areas. One man saw over a hundred dead tadpoles on car windshields in one parking lot after a rain shower.

On June 13, 2018, shrimp and possibly other sea creatures fell on the coastal city of Qingdao [zhing-daugh], China during a storm. The media reported it as a “seafood rain” since people posted photos of octopus, squid, starfish, mollusks, and shrimp that they claimed had fallen during the storm. Some of the photos are hoaxes, especially the ones of octopuses flying through the air, but at least some of them are real. Some people speculate that the source of the animals may have actually been a market stall, but since the city is on the coast of the Yellow Sea and the storm’s winds were measured at 77 mph, or 125 km per hour, it’s just as likely that the animals were lifted into the air from shallow water as from a market stall.

Sometimes we can figure out what the cause is of falling animals. In 2015 the Alaska Department of Fish and Game received four separate calls from people who’d found arctic lampreys on their property, including the parking lot of a store and someone’s front yard. If you remember from waaaaay back in episode 3, where we talked about the sea lamprey, lampreys are jawless fish with suckerlike mouths. They latch onto a fish and use their rasping teeth to parasitize it. The arctic lamprey grows to about a foot long on average, or 30 cm, but occasionally one will grow twice that long. It lives in cold freshwater lakes and rivers in the arctic, although it’s found as far south as Japan. An investigation revealed that all four lampreys found on land had cut marks and bruises in a specific pattern, which indicated that they’d been picked up in the beak of a seagull and then dropped, probably by accident when the lamprey wriggled too much. In 2015 there were an unusually high number of arctic lampreys in the Chera River, near where the four lampreys were reported on land.

A substance often referred to as star jelly or star rot has been seen in various parts of the world for centuries, usually connected in folklore with comets and shooting stars. In late 2008 through February 2009 the BBC’s Scotland Outdoors website collected photos and accounts of star jelly people had encountered in Scotland and other places. People reported finding lumps of the usually clear or white, jelly-like substance in their gardens, on walkways, on fence posts, stumps lawns, on the side of the road, in pastures, on rocks, and so on. One person found a lump of it on his tractor, another on a 3rd floor balcony.

Even hundreds of years ago some people suspected star jelly had something to do with frogs. At least some of it looks like the jelly-like matrix that surrounds the eggs of many frog and toad species. This is backed up by the presence of small black eggs in some star jelly that look like frog eggs. But it’s clearly not exactly frog spawn and is often found in places where a frog would never lay its eggs, even if it could for instance get up onto a third floor apartment balcony.

Many samples of star jelly have been examined by scientists and found to be the spawn jelly of frogs and toads, which is produced by the female to surround the eggs and keep them damp. As the female lays her eggs, each one is coated with a layer of spawn jelly, which absorbs water in the environment and increases in volume. Sometimes when a predator tears a frog or toad into pieces to eat it, the reproductive tract is torn open and its contents falls to the ground. When the spawn jelly is exposed to the air, it starts to absorb moisture from whatever it’s touching. This will make it swell up and become much more noticeable to people, especially if it’s rained and the spawn jelly has absorbed a lot of water.

Often an animal will eat a frog or toad, then later regurgitate the less digestible parts. This includes spawn jelly and some parts of the reproductive tract, specifically the oviducts since they contain the spawn jelly. Sometimes eggs are mixed in too. Star jelly has been examined and tested frequently, although most DNA testing has been inconclusive since samples are contaminated with bacteria. But a 2015 DNA test determined that the star jelly was from a frog. The test also found traces of magpie DNA, so we can probably guess what ate the frog.

Some star jelly doesn’t have anything to do with amphibians, though. Instead, some are slime molds or a type of freshwater algae-like bacteria known as nostoc. Neither slime molds nor nostoc fall from the sky but they can appear suddenly, so people may assume that’s what happened. Many birds that eat frogs and toads will eat them in midair, and may also regurgitate the indigestible portions while flying, so at least some star jelly does fall from the sky.

Sometimes people assume an animal has fallen from the sky when it actually hasn’t. For instance, the walking catfish will wriggle across dry land to find water when its pond dries up. It can grow up to 1 ½ feet long, or half a meter, and is usually grayish-brown with little white spots. Its skin is covered with mucus that helps keep it from drying out when it’s out of water. It’s native to parts of Southeast Asia, but it’s been introduced to other places, including southern Florida. In places where it’s not native, people may not be familiar with its ability to breathe air and move around out of the water, so when they see the walking catfish on land they may assume it fell from the sky.

The walking catfish is an invasive species in many areas. It’s an omnivore and can tolerate all kinds of habitats, including stagnant water where other fish can’t survive, since it can breathe air. Fish farmers in areas where the walking catfish lives have to put fences up around their ponds to keep walking catfish out. And if you see one, don’t pick it up. Its fins have spines that help stiffen them so it can use them to move more effectively on land, but that make them sharp.

We obviously don’t know everything about animals that fall from the sky, so let’s finish with a real mystery. It’s called the Kentucky Meat Shower and it happened on March 3, 1876 in a tiny community called Olympia Springs, Kentucky.

Olympia Springs is east of Lexington, Kentucky, in the southeastern United States. These days it’s in the Daniel Boone National Forest and just outside of the Olympia State Forest, so there’s not much in the area except wilderness. This was probably also the case in 1876 except that in 1876 there probably wasn’t a Dairy Queen restaurant a ten minute drive away. Wikipedia says it happened in a community named Rankin in the same county, but most other sources say Olympia Springs. Either way, it was an isolated, remote area at the time.

On this particular day, a woman only identified as Mrs. Crouch was in the yard, making soap. It was a perfectly clear day, not a cloud in the sky, when suddenly it started raining meat. She said it fell like big snowflakes all around her, but presumably not as pretty as snow, and lasted for several minutes. It was fresh meat, looked like beef or other red meat, and the pieces were irregularly shaped and gristly. Some were as big as 4 inches across, or 10 cm, but most about half that size. The meat landed all around, including on fences, in an area estimated to be about 100 yards across and 50 yards wide, or 91 by 46 meters.

Mrs. Crouch and her husband were understandably shaken by this event, and records don’t report whether the soap got finished that day but I suspect not. The next morning, the meat was still lying around, but it had dried out overnight and was starting to spoil. A couple of men stopped by and actually tasted it—ugh, I hope they at least cooked it first—and said they thought it might be venison or mutton. That’s meat from deer and sheep, respectively.

Samples of the meat were sent to various experts who examined it. Keep in mind that this was 1876 so they couldn’t do much more than look at it under an old-timey microscope. Two samples were identified as lung tissue, two as cartilage, and three as muscle.

As soon as the story hit the newspapers, people were quick to offer solutions that didn’t actually fit the reported facts. One person suggested that it was just nostoc that hadn’t actually fallen from the sky, it had been on the ground all along but that rain had made it swell up, which is something nostoc does. Never mind that nostoc is a slimy bacteria that looks nothing like meat—remember, it’s sometimes identified as star jelly—and that it wasn’t raining at the time and that Mrs. Crouch actually saw it fall and that pieces of it were found draped over fences. Plus, nostoc doesn’t taste like venison or mutton. Plus, samples were identified as actual meat.

The main suggestion is that some vultures were flying overhead and had disgorged some meat they had eaten, which had been caught by the wind and fell across a wide area. But while even nowadays people claim that is what must have happened, it has one big flaw. Vultures don’t disgorge meat while they’re flying. They disgorge it as a way to deter predators approaching their nest, and they may disgorge if a predator approaches while they’re feeding so they can get into the air quickly, but not while flying. Not only that, but any meat disgorged by a vulture would smell and taste horrible, since it would have already been rotting before the vulture ate it, and it would then be coated with caustic vulture digestive juices.

So what might have caused the Kentucky Meat Shower? If it wasn’t a newspaper hoax, which were really common in the late 19th century, it might have been the result of some poor animal that was swept up by a tornado, torn apart, and the smallest pieces dropped over the Crouch’s farm after the winds had dissipated. Presumably the heavier pieces, like bones, fell earlier and probably landed in the forest where no one saw them fall. I looked for a weather report for Kentucky for that day, but couldn’t find one. Eastern Kentucky is not too far north from where I live in East Tennessee, so I can verify that March can be a very warm month with unsettled weather. It wouldn’t be at all unusual to have a storm strong enough to generate a small but powerful tornado in March, although this usually happens at night after a hot day.

I don’t know if I believe the Kentucky Meat Shower really happened or if it was a hoax. But either way, we can stop blaming vultures.

You can find Strange Animals Podcast online 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. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 136: Smallest of the Small

Last week we learned about the smallest species of animals not typically thought of as small, like snakes and cetaceans. This week let’s look at some of the tiniest animals in the world, the smallest of the small!

Further watching:

A short video about jerboas. Really interesting and well-made!

A button quail:

Baby button quails are the size of BEES:

Kinglets are teeny birds even when grown up. Left, the golden-crowned kinglet. Right, the goldcrest. These birds MAY BE RELATED, you think?

The pale-billed flowerpecker, also teeny and with a cute name:

Moving on from birds, the pygmy jerboa is one of the smallest rodents in the world:

The Etruscan pygmy shrew is even tinier, probably the smallest known mammal alive today. Shown here with friend/lunch:

The Western pygmy blue butterfly is probably the smallest butterfly known:

But the pygmy sorrel moth is even smaller. Right: red marks left behind on a sorrel leaf eaten by its larvae:

One of the world’s teeniest frogs:

Show transcript:

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

Last week we learned about the smallest species of animals that aren’t typically thought of as small. But this week let’s learn about the smallest of the small animals. It’s like saying they’re the cutest of the cute animals. We’ll start with the bigger ones and get smaller and smaller as we go.

Let’s start with a bird. The smallest bird is the bee hummingbird, which we’ve talked about before. But there’s another bird that’s really small, the button quail. It’s about the size of a sparrow.

The button quail isn’t actually a quail, but it looks like one due to convergent evolution. There are a number of species in parts of Asia and Africa and throughout Australia. It generally lives in grasslands and is actually more closely related to shore and ocean birds like sandpipers and gulls than to actual quails, but it’s not very closely related to any other living birds. It can fly but it mostly doesn’t. Instead it depends on its coloring to hide it in the grass where it lives. It’s mostly brown with darker and lighter speckled markings, relatively large feet, and a little stubby nothing of a tail. It mostly eats seeds and other plant parts as well as insects and other invertebrates.

The button quail is especially interesting because the female is more brightly colored than the male, although not by much. In some species the female may have bright white markings, in some their speckled markings are crisper than the males. The female is the one who calls to attract a male and who defends her territory from other females. The female even has a special bulb in her throat that she can inflate with air to make a loud booming call.

The male incubates the eggs and takes care of the chicks when they hatch. Baby button quails are fuzzy and active like domestic chicken babies but they’re only about the size of a bumblebee. In many species, as soon as the female has laid her eggs, she leaves them and the male and goes on to attract another male for her next clutch of eggs.

People sometimes keep button quails as pets, specifically a species called the painted buttonquail or the Chinese painted quail. It’s about five inches long, or 12 cm. The female has black and white stripes on her face and throat. The birds can become quite tame and can live several years.

Button quails make a lot of different noises. This is what a button quail sounds like:

[button quail calls]

One of the smallest birds in the world that isn’t a hummingbird is the kinglet, with several species that live in North America and Eurasia. The goldcrest is a type of kinglet and the smallest European bird. It’s only 3.3 inches long, or 8.5 cm, although some individuals are larger. It looks a lot like the North American bird the golden-crowned kinglet, which is just a shade smaller at 3.1 inches, or 8 cm. Both species have a golden patch on the top of the head. The male also has an orangey spot in the middle of the golden patch. Both live in coniferous forests and eat insects and spiders.

Because kinglets are so small and active, they can starve to death quickly—in only an hour in some cases. Females lay up to 12 eggs at a time. TWELVE EGGS. That is a lot of eggs. The nest is too small to hold a dozen eggs in one layer so they end up in a pile. The female keeps all of them warm by pushing her legs down into the pile of eggs. Since her legs have a lot of blood vessels near the surface, they’re much warmer than most birds’ legs.

When the babies hatch, they stay in a pile. The ones on the top of the pile get fed first, naturally, but then they burrow down into the pile and push their siblings up toward the top. They’re not just being nice, though, since birds in the bottom of the pile stay warmer.

This is what a golden-crowned kinglet sounds like:

[bird call]

The pale-billed flowerpecker is even smaller than the kinglets and are among the smallest birds in Asia. It lives in parts of India and nearby areas and mostly eats berries, although it also eats flower nectar. It grows to only 3 inches long, or 8 cm, and is plain brownish-green in color with a short tail and shiny black eyes. It lives in forests but often visits gardens. It doesn’t lay a dozen eggs at a time, just an ordinary two or three.

This is what a pale-billed flowerpecker sounds like. These are some teeny sounds from teeny birds:

[bird call]

There are several rodents that are considered the smallest rodent, but we’re only going to learn about one of them today, the pygmy jerboa. On average it’s only 1.7 inches long, or 4.4 cm, not counting its extremely long tail.

The pygmy jerboa lives in the deserts of Pakistan and possibly in nearby areas too. It has very long hind legs and very short front legs so it hops like a tiny kangaroo, using its long tail as a way to balance and maneuver at high speeds. Its tail is twice as long as its body. Its large hind feet and the end of its tail are very furry to give it more surface area so it can easily maneuver through loose sand.

It mostly eats seeds and leaves, and it gets all the moisture it needs from the food it eats. It’s nocturnal and spends its days in the burrow it usually digs under bushes. Like many other tiny animals, when it rests it slows its metabolism drastically so it won’t starve to death while it’s asleep. Life is rough for tiny animals.

We don’t know a whole lot about the pygmy jerboa except that it’s endangered due to habitat loss, so let’s move on to an even smaller mammal.

The Etruscan shrew grows to about 1.6 inches long, or 4 cm, on average, not counting its short tail. The tail is about a third of the length of its body. It lives in southern Europe, parts of Asia, parts of the Arabian Peninsula, and northern Africa and prefers warm, moist climates. It’s the same size and weight as the bumblebee bat we talked about last week, so it’s one of the smallest mammals known.

The Etruscan pygmy shrew is pale brown with a lighter colored belly, a long nose, and short whiskers around its mouth that it uses to help it find its prey. It’s incredibly active and makes clicking noises almost constantly, as a way to alert other shrews that it’s there and is willing to defend its territory. It makes its nest among rocks and in the abandoned burrows of other animals.

Like the kinglets and other highly active, tiny animals, it has to eat a lot to keep its metabolism going—up to twice its own weight in food every day. It can also enter a torpid state where it reduces its body temperature and metabolism the same way the pygmy jerboa does, in order to not starve while it sleeps. But the Etruscan shrew doesn’t rest very often.

It mostly eats insects and other invertebrates like earthworms, but it will eat anything it can kill. This includes lizards, small rodents, and frogs. It especially likes grasshoppers and crickets, which are often as large as it is. In order to kill prey its own size, the shrew is incredibly fast. If you remember episode 82 where we talked about the star-nosed mole, the Etruscan shrew primarily hunts by touch and can react in barely 25 milliseconds when it touches something it wants to eat. It takes something like 300 milliseconds for a human to blink their eyes, if that gives you an idea of how fast the shrew is. It can touch a cricket and kill it in less time than it takes to blink.

So that’s as small as mammals get, as far as we know. What’s the smallest amphibian?

Well, it’s really, really small. The smallest known frog is only 7.7 mm long. Paedophryne amauensis isn’t just the smallest frog, it’s the smallest vertebrate known. It was only discovered in 2009 in Papua New Guinea.

It sounds like an insect and lives in the damp leaf litter on the forest floor, and it’s dark brown and black in color to blend in with dead leaves, so it was hard to find. Researchers only found it by using sensitive microphones to triangulate on its call, then quickly scooping up lots of leaf litter and stuffing it into plastic bags so anything living in the leaves couldn’t escape. Its eggs hatch into tiny froglets instead of tadpoles.

The tiniest frog is just about the same length as the tiniest fish, the stout infantfish that lives in a few coral reefs near Australia, including the Great Barrier Reef. It also grows 7.7 mm long on average, although females are typically longer and it can grow as much as 10 mm long. But the smallest known fish is the male of an anglerfish species that only grow 6.2 mm long. This doesn’t really count, though, since females grow up to two inches long, or 50 mm. Like other deep-sea anglerfish species, when a male of Photocorynus spiniceps finds a female, he bites her and stays there. Eventually his mouth actually fuses to her body and he lives the rest of his life as a sort of parasitic extension of the female. He supplies her with sperm to fertilize her eggs before she lays them, and she supplies him with nutrition and oxygen since he’s basically part of her body at that point. A female can have more than one male fused to her.

So, we seem to have reached the smallest vertebrates. What about the smallest insects and other invertebrates?

Butterflies are generally pretty small, but the smallest butterfly known is really, really small. The Western pygmy blue butterfly only has a wingspan of 20 mm at most but usually more like 12 mm across. That’s less than an inch. It lives in western North America and parts of the middle east, and has even been found on Hawaii. Its wings are a pretty coppery brown color with rows of black and white spots. It likes deserts and waste places where you wouldn’t expect to find anything as delicate as a tiny butterfly. Its caterpillars eat various types of weed plants.

That is pretty much it. There’s not much to this tiny butterfly. The real mystery is why it’s called the western pygmy blue when it’s not actually blue.

Compared to the smallest moth known, the western pygmy blue butterfly is a giant. The smallest moth is the pygmy sorrel moth and its wingspan is barely four millimeters. Its wings shade from silvery with a metallic bronze tint to purply with a white stripe, and gray along the ends. It’s really pretty but so tiny that it’s hard to spot. It lives in much of Europe and its larvae leave distinctive spiral shapes on sorrel leaves as it eats.

We’ll come back to insects in a minute or two, but let’s look at a few snails first. The smallest land snail is the Borneo snail. Its shell is only .7 of a mm high. It was only discovered in 2015. We don’t know a lot of about it yet, but it probably eats bacterial film growing on limestone in caves. So far researchers haven’t even found a living Borneo snail, though, just its shells.

The smallest water snail is even smaller than the Borneo snail. It’s from North America and its shell is only half a millimeter across at the most. Some individuals are only .3 mm across. Ammonicera minortalis lives in shallow water off the coast of southern Florida and around Cuba and other islands in that area. And that’s pretty much all we know about it. It’s a lot easier to study bigger animals just because they’re easier to find.

Small as that is, on average the smallest beetle is smaller than the smallest snail. It’s a type of featherwing beetle only described in 1999, and on average it’s .338 mm long. So far it’s only been found in Central America and it eats fungus. It’s yellowish-brown in color but that doesn’t really matter because it’s so small that you need a magnifying glass to really see it.

Once you start dividing millimeters, you’re getting into ridiculously tiny territory. But the smallest insect is a type of wasp known as a fairyfly. Kikiki huna is so small it’s measured in micrometers, sometimes called microns, and is smaller than some single-celled organisms. It’s only 150 micrometers long, which is shorter than an ordinary piece of printer paper is thick. It’s been found on Hawaii, Costa Rica, and Trinidad but it probably lives in other places but just hasn’t been found yet. Some researchers suspect that it’s as small as a flying animal can become without losing the ability to fly under its own power instead of just floating on the wind.

At this point anything smaller than Kikiki huna and its close relatives are made up largely of bacteria, which are frankly not as cute or as interesting as, say, button quail. So let’s finish with what may be the very smallest living organism ever found. Or it may not be. Because researchers are literally not even sure if the nanobe is even alive.

In 1996 researchers found what looked like filiments growing among rock samples collected from wells off the Australian coast. Some of them were only 20 nanometers in diameter. To put that into perspective, a nanometer is one billionth of a meter. That’s billion with a B. It’s one thousandth of a micrometer. A nanobe is a tenth of the size of the smallest known bacteria.

The researchers weren’t sure what they’d found so they did a lot of tests. They thought they might have discovered a new kind of crystal, but when they stained the nanobes with a type of dye that binds to DNA, the results indicated the nanobes might be living organisms. But no DNA has been successfully recovered from nanobes.

There’s still a lot of research to be done to determine what they are and if they’re actually alive, though. The main problem is that nanobes appear to be too small to contain all the things that living organisms need. But they do resemble fungi in some ways, just much, much smaller. If nanobes are alive, they’re extremely different from any living animal ever known and presumably live and reproduce in ways completely unlike all other life.

But here’s an interesting note. In 1996 researchers found structures inside a meteorite from Mars that look a lot like nanobes.

You can find Strange Animals Podcast online 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. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 133: The mangrove killifish and the unicorn pig

This week’s (short) episode is about two animals that should have been in the strangest small fish and weird pigs episodes, respectively. I left them out by accident but they’re so interesting that they deserve an episode all to themselves anyway. Thanks to Adam for suggesting the mangrove killifish!

Further reading:

25 Years in the Mud: How a Quirky Little Fish Changed My Life

The mangrove killifish just looks normal:

Not a unicorn pig (okay yes technically a unicorn pig):

Unicorn pig skull:

Show transcript:

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

A few weeks ago we had an episode about strange small fish. Shortly after that episode released, I was going through my disorganized ideas and suggestions file and realized I’d left out one of the best weird small fish ever, a suggestion by Adam. I also discovered I’d missed an extinct pig I’d planned to include in the recent weird pigs episode. So let’s play catch up in a short episode and learn about both this week.

The fish Adam suggests is called the mangrove killifish, also called the mangrove rivulus, which lives in parts of Florida and Mexico, down to Central and South America. It’s technically a marine fish, meaning it lives in salt-water, but it also likes brackish water, that’s less salty than the ocean, and occasionally it even lives in freshwater. It especially likes mangrove swamps. It grows up to 3 inches long, or 7.5 cm and is a mottled brown in color with an eye spot on its tail. It doesn’t look like anything special.

But the mangrove killifish has a lot in common with amphibians, especially the lungless salamanders. Many types of salamander absorb air through the skin instead of through lungs or gills. The mangrove killifish does this too. It often lives in abandoned crab holes, which may not have very high quality water. But that’s okay, because it can absorb air through its skin and can live out of the water for well over a month as long as its skin stays damp. It’s sometimes found in places where you wouldn’t expect to find a fish, like the inside of rotting logs or buried in damp dead leaves.

So how does the killifish get into the rotting logs or the leaf litter or the crab burrows that aren’t connected to waterways? It actually uses its tail to flip itself out of the water and onto land, and then it continues to flip here and there until it finds a place where it wants to live for a while. It can direct this jumping, not just flop around like most fish out of water, and can jump several times its own length.

A lot of times when the tide goes out, fish get trapped in crab holes, dimples in the sand or mud, and other shallow water. That’s okay if the tide comes back in far enough to re-submerge the holes, but if the water doesn’t quite reach, it’s not long before fish start to suffocate as all the oxygen in the water is used up. But the killifish doesn’t have that problem. It just flips itself out of the water. It can also leave the water if it gets too hot.

The killifish is also territorial in water, which requires a lot of energy. When it’s out of the water, or in a little temporary pool or a crab burrow where it doesn’t have to worry about other killifish, it can relax. On the other hand, it loses a lot of weight while it’s out of the water since it doesn’t eat as much. So there are trade-offs.

Even the killifish’s eggs can survive out of water. The fish usually lays its eggs in shallow water, sometimes even on land that’s just near water. The eggs continue to develop just fine, in or out of water, but they delay hatching until they’re submerged.

And that leads us to the most astonishing thing about the mangrove killifish. In most populations, almost all killifish are females, and most of the time they don’t need a male fish to fertilize their eggs. Females produce eggs but they also produce sperm that fertilize the eggs before they’re even laid. The eggs hatch into genetic duplicates of the parent—clones, basically. The term for an organism that produces both eggs and sperm is hermaphrodite, and while it’s common in some invertebrates, the killifish is the only known vertebrate hermaphrodite. Vertebrate, of course, is an animal with a backbone.

But while most killifish are females, there are occasionally males. Male killifish are orangey in color. When a male is around, females suppress their ability to self-fertilize eggs and they lay the eggs for the male to fertilize, just like any other fish. This helps keep the species genetically diverse and able to adapt to external pressures like increased numbers of parasites.

Next, let’s talk about the unicorn pig. Or pigicorn, if you like. It’s called Kubanochoerus [koo-ban-oh-ko-rus] and there were several species. It was related to modern pigs and lived throughout most of Eurasia and parts of Africa around 10 million years ago.

It was big, up to four feet tall at the shoulder, or 1.2 meters, and had tusks like other pigs. It probably looked a lot like a wild boar. But its skull is longer than modern pig skulls and it had horns. Three horns, specifically. Two of the horns were small and grew above the eyes, while a bigger horn grew forward from its forehead. The forehead horn wasn’t very long and was probably blunt. Researchers used to think males used these forehead horns to fight each other, but females had them too so they may also have been used for defense from predators.

That is literally all I can find out about this fascinating animal. I can’t even speculate about the horns since literally no other pig has horns, at least that I can find. Presumably the warty protrusions that many modern pig species have are similar to the horns that Kubanochoerus had. The eyebrow horns might have had the same purpose as the facial protrusions on warthogs and other pigs, as a way to protect the eyes when the pigs fight. The forehead horn, though…well, that’s just weird. It probably wasn’t covered with keratin, but we don’t know. My own guess is that it was something more like an ossicone and was covered with skin and hair. But again, we don’t know. Not until we invent a working time machine and go back to look at one.

That’s it, a very short episode. I’m actually in Dublin, Ireland right now attending WorldCon, so while I’m here I will keep an eye out for leprechauns, fairies, and pigicorns, just in case.

You can find Strange Animals Podcast online 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. We also have a Patreon if you’d like to support us that way.

Thanks for listening!