Category Archives: fossils

Episode 057: Horseshoe Crabs and Cone Snails

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Let’s learn about horseshoe crabs and cone snails! The former is harmless, the latter is deadly. Both are interesting!

This episode’s animals are inspired by the podcast Animals to the Max and by the book Strange Survivors by Dr. Oné R. Pagán. Check both out because they are awesome!

A horseshoe crab will never hurt you and just wants to be left alone to be a horseshoe crab:

A trilobite fossil:

A cone snail just wants to be left alone to be a cone snail but it will kill you if it has to:

Above: the stripey tube thing is the snail’s siphon, the pink tube thing is the snail’s proboscis, or VENOM DUCT.

The Glory of the Sea has a pretty shell:

More cone snail shells:

The rarest seashell in the world:

Show transcript:

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

This week we’re going to look at animals inspired by a book I recently read and a podcast I recently discovered.

The podcast is called Animals to the Max, and it’s one of several new animal podcasts that I’ve been enjoying lately. In most episodes, the host Corbin Maxey interviews someone who works with animals. Recently I was listening to episode 15, and the subject of horseshoe crabs came up briefly. Those things are awesome and well deserving of the term living fossil, so let’s start there.

First of all, horseshoe crabs are not actually crabs. They’re not even crustaceans. In fact, they’re more closely related to spiders and scorpions than to crustaceans. There are four species of horseshoe crabs alive today, three from Asia and one from the Gulf of Mexico and American Atlantic coast. Females are larger than males and depending on the species, may be about a foot long including the tail, or 30 cm, or twice that length.

The horseshoe crab gets its name from its rounded, slightly domed carapace that’s kinda sorta the shape of a horse’s hoof, with a long spike of a tail sticking out from its rear. It has a ridiculous number of eyes—seriously, it has nine eyes plus some photoreceptors on its tail. But it doesn’t see very well. Mostly it just senses light, although it can also see into the ultraviolet range.

It also has five pairs of legs tipped with little claws, and its mouth is in the middle of the base of its legs. Its legs act as shredders to cut up its food into tiny pieces. It eats worms and other invertebrates, and will eat fish if it can get it. Most of the time it swims upside-down. It can breathe air on land for short periods of time as long as its gills stay damp. Oh, and it can regenerate legs if one is injured.

Horseshoe crab blood is blue because instead of hemoglobin, its blood contains hemocyanin to transport oxygen throughout the body. Hemoglobin contains iron, which is red, while hemocyanin contains copper, which is blue. Its blood also contains amebocytes instead of white blood cells, and amebocytes have medical applications for humans, specifically as a way to detect bacteria in medical equipment. That means horseshoe crab blood is valuable. Half a million horseshoe crabs are caught every year, up to 30% of their blood is harvested, and the crabs released back into the wild none the worse for wear. At least, that’s how it’s supposed to go. In fact, almost 30% of the horseshoe crabs released just up and die due to stress, and some companies don’t even release them. They just quietly sell them as bait. Horseshoe crabs have been used as commercial fishing bait and ground up as fertilizer for years. Because of all these pressures, along with pollution and the development of beaches where they lay their eggs, the horseshoe crab has gone from being one of the most numerous animals in the ocean to threatened in a matter of decades. Fortunately, many places have put protections and harvesting limits in place to help the population rebound.

Horseshoe crabs first appear in the fossil record 450 million years ago, near the end of the Ordovician Period, back when most life lived in the oceans and fish with jaws were only just evolving. This was well before dinosaurs. This was well before any animals were living on land at all, although probably some marine animals had discovered that if they laid their eggs on the beach, nothing much would eat them, and some other marine animals had discovered that if they could haul themselves out onto the beach for short periods of time, they might find some eggs to eat. The horseshoe crabs alive today are basically identical to the horseshoe crabs found throughout the fossil record. They hit on a successful body plan hundreds of millions of years ago and have stuck with it ever since.

Trilobites were also everywhere during the Ordovician as well as before and after, until they died out 252 million years ago. Trilobite fossils are really common so you’ve probably seen them, but they looked sort of like big roly-polies, or pill bugs, or sow bugs, depending on what you call them. Horseshoe crabs are actually related to trilobites, and one of the big questions is why trilobites died out after being so incredibly successful for so long—270 million years—while horseshoe crabs didn’t. It was probably just luck. The Great Permian Extinction event wiped out almost 90% of all life on earth, and even before then trilobites were already in decline, while the horseshoe crab was chugging along just fine.

If you’re on the beach and see a horseshoe crab on its back, trying to get right side up, help it by flipping it onto its feet. It won’t hurt you, and you might very well save its life.

The other animal I want to look at today is the cone snail, inspired by a brand new book called Strange Survivors by Oné Pagán. Dr. Pagán kindly sent me an advance copy and it is definitely a book a lot of you would find interesting. It’s about evolutionary forces and how things like venom developed in various animals. I’ll put a link in the show notes if you want to order a copy for yourself. One of the animals Dr. Pagán talks about in the book is the cone snail. I’d never heard of it before but it’s fascinating.

There are something like 800 species of cone snail, in fact. They live in tropical oceans and their shells often have beautiful geometric patterns, the kind collectors spend big bucks for. But all cone snails are venomous and some can be fatal. Cone snails are snails and therefore not exactly known for their speed, but the larger ones hunt and kill fish. How do snails hunt fish? Usually it’s the other way round.

Well, let me just tell you. You are not even going to believe this, but you should, because it is a real thing that actually happens. I’ll use the geographic cone snail as an example, because it’s been well studied. It’s about 6 inches long, or 15 cm, and is common throughout shallow reefs in the Indian Ocean and the Red Sea. It’s also the most toxic of cone snails, and there is no antidote to its venom.

So, imagine a cone snail on the bottom of a shallow, warm ocean. Small fish are swimming around. The cone snail has a mottled brown and white shell, quite pretty, and the snail itself is somewhat similar in color with a siphon sticking out of the bottom of its shell. It’s not bothering anything and some little fish ignore it because hey, they’re fast fish and it’s just a slow snail.

But when the little fish get close to the snail, something odd happens. They just sort of slow down. They stop moving and sink to the bottom, but they don’t act panicked. That’s because the snail has released venom into the water, venom containing insulin that mimics the insulin found in fish. When a fish absorbs the venom through its gills, it goes into hypoglycemic shock, which stuns it. The snail then fires a modified hollow tooth called a harpoon into the fish, injecting more venom and killing the fish. The harpoon is attached to the snail’s body by a proboscis, or venom duct, which the snail uses to winch the fish into its mouth to digest.

So far researchers have found two snails that stun fish with venom released into the water, the geographic and the tulip cone snails, but all cone snails have the harpoon contraption to shoot fish with. And the harpoon is fast. It travels at about 400 miles per hour, or 644 km per hour, and special muscles at the base of the venom duct can pump venom into the fish just as fast. Sometimes a snail will hide in the mud or sand and wiggle its proboscis like a worm, and when a fish comes to investigate, the snail harpoons it. It takes the snail a week or two to digest a fish, and during that time it also grows a new harpoon.

Cone snails also use their harpoons defensively, and they can penetrate right through clothes and even divers’ wetsuits. And the venom can kill a human in a matter of hours. The problem is that many cone snail shells are really pretty, so people pick them up to look at. The snail thinks it’s about to be eaten, defends itself, and the person thinks, “Ow, that felt funny. And my hand is going numb. Hmm. Now my whole body is going numb, how strange.” And then they die. Well, it takes longer than that, but you get the idea. Of course, only 36 people have actually died from cone shell stings in the last 90 years, but just a reminder that if you don’t get in the water you are probably safe from venomous marine snails.

On the other hand, researchers are very interested in the cone snail’s toxins. They could lead to painkillers that don’t cause dependency, better treatments for diabetes, and even treatments for nervous system disorders like Parkinson’s disease and Alzheimer’s. At least one painkiller developed from peptides in a cone snail toxin is already on the market.

One cone snail, the Glory of the Sea, was at one time thought to be the rarest shell in the world. In 1970 its habitat was discovered by divers, in various places throughout the Indo-Pacific but mostly near the Solomon Islands. Before then, though, collectors would spend thousands of U.S. dollars on a specimen. These days they can still go for around one or two hundred bucks just because they’re really pretty and still not terribly common. I’ll put a picture of one in the show notes.

This episode is a little short so let’s just plunge down this rare shell rabbit hole. The rarest shell in the world is arguably that of Sphaerocypraea incomparabilis, and its story is pretty awesome. In 1963 a trawler dredged up a dark brown cowrie type shell that made its way to a Russian shell collector. Rumors of the shell leaked out and in the 1990s, a collector named Donald Dan flew to Moscow and managed to buy the shell. It turned out to be the shell of a snail that had been thought extinct for 20 million years. It’s still extremely rare, though. Only six of the shells are known to be in collections and the living snail still hasn’t been examined by scientists or formally described.

I don’t want to get in the water more than about ankle deep, but I do enjoy beachcombing. Apparently there’s some money to be made in shell collecting, too, but don’t pick up any cone snail shells unless you’re 100% certain the shell is empty.

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

Thanks for listening!

Episode 055: Lungfish and the Buru

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Let’s learn about the LUNGFISH, which deserves capital letters because they’re fascinating and this episode took so flipping long to research! Mysteries abound!

The lovely marbled lungfish from Africa:

The South American lungfish:

The Australian lungfish CHECK OUT THOSE GAMS:

Another Australian lungfish:

Further Reading:

The Hunt for the Buru by Ralph Izzard

Show Transcript:

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

This week’s episode is about the lungfish, and I’m going in depth about some mystery lungfish later in the episode. So don’t give up on me if you think freshwater fish are boring.

Lungfish are unusual since they are fish but have lungs and can breathe air. Some fish species can get by for a short time gulping air into a modified swim bladder when water is oxygen poor, but the lungfish has real actual lungs that are more mammal-like than anything found in other fish. The ancestors of lungfish, which developed during the Devonian period nearly 400 million years ago, may have been the ancestors of modern amphibians, reptiles, birds, and mammals. This is still a controversial finding, but a 2017 molecular phylogenetic study identified lungfish as the closest living relatives of land animals.

Africa has four species of lungfish, from the smallest, the gilled African lungfish that only grows around 17 inches long, or about 44 cm, to the largest, the marbled lungfish, which can grow more than six and a half feet long, or two meters. They all resemble eels, with long bodies and four thin, almost thread-like fins. They mostly eat crustaceans, molluscs, and insect larvae. The adults have small gills but breathe air through their lungs exclusively.

The South American lungfish is in a separate family from the African lungfishes, but it’s very similar in most respects. It can grow over four feet long, or 125 cm, and looks like an eel at first glance. Its fins are thread-like and not very long, and while it has small gills, they’re nonfunctional in adults. It mostly eats snails and shrimp, and like the African lungfishes, its teeth are fused into tooth plates that crush the shells of its prey easily.

Baby South American and African lungfish have external gills like newts but look more like tadpoles. After a couple of months they develop the ability to breathe air.

The African and South American lungfishes live in swamps and shallow river basins, and during the dry season, the water of their homes may dry up completely. At the onset of the dry season, the lungfish burrows a foot or two deep into the mud, or 30 to 60 centimeters, and lines the burrow with mucus to keep its body from drying out. Then it curls up in the bottom of the hole and lowers its metabolism, and stays there for months until the rains return and soak its dried mud home. This is called aestivation, and it’s related to hibernation except that it usually happens in warm weather instead of cold.

The Australian lungfish, also called the Queensland lungfish, lives in Australia and retains many features that are considered primitive compared to other lungfish species. It’s so different from the other lungfish species it’s even in a different order. Let’s learn about just how different it is and why that’s important.

In 1869 a farmer visiting the Sydney Museum asked why there were no specimens displayed of a big olive-green fish from some nearby rivers. The curator, Gerard Krefft, had no idea what the guy was talking about. No problem, the guy said, or probably no worries, he’d just get his cousin to send the museum a few. Not long after, a barrel full of salted greenish fish that looked like big fat eels arrived and Krefft set about examining them.

When he saw the teeth, he practically fainted. He’d seen those teeth before—in fossils several hundred million years old. No one even knew what fish those teeth came from. And here they were again in fish that had been pulled from a local river only days before.

The Australian lungfish doesn’t have ordinary teeth, it has four tooth plates or combs that resemble regular teeth that have fused together. Its skull is also very different from all other fish, possibly because of its feeding style. It crushes its prey with its tooth combs, so its skull has to be able to withstand a lot of pressure from the force of its own bite. Other lungfish species share this trait to some degree, but with modifications that appear more recent.

The Australian lungfish lives in slow-moving rivers and deep ponds and hunts using electroreception. Larger ones mostly eat snails and crustaceans, while smaller ones also eat insect larvae and occasionally small fish. It can grow up to about five feet long, or 150 cm. Its body is covered with large overlapping scales, and its four fins look more like flippers or paddles. Its tail comes to a single rounded point. In short, it looks superficially like a coelacanth, which is not a big surprise because it’s related to the coelacanth. While the Australian lungfish doesn’t actually get out of the water and walk on its fins, it does stand on them and sometimes walks around on them underwater.

Unlike the other lungfishes, the Australian lungfish has only a single lung instead of a pair. Most of the time it breathes through its gills, but at night when it’s active, or during spawning season or other times when it needs more oxygen, it surfaces periodically to breathe. When it does so, it makes a distinctive gasping sound. During droughts when its pond or river grows shallow, an Australian lungfish can survive when other fish can’t. As long as its gills remain moist, it can survive by breathing air through its lung. But unlike other lungfish, it doesn’t aestivate in mud.

The Australian lungfish hasn’t changed appreciably for the last 100 million years. The only real change it exhibits from its ancestors 300 million years ago is that it’s not as big, since they grew some 13 feet long, or 4 meters. Lungfish used to be widespread fish that lived in freshwater back when the world’s continents were smushed together in one supercontinent called Pangaea, some 335 million years ago. When Pangaea began to break up into smaller continents about 175 million years ago, various species of lungfish remained in different parts of the world. Now we’ve only got six species left…maybe.

A lot of mysterious eel-like fish or fish-like lizard stories might refer to lungfish. Some of the mystery animals are probably extinct, whatever they were, but some might still be around. All known lungfish were only discovered by science within the last 150 years or so, and it’s quite possible more are lurking quietly in remote swamps and rivers.

That brings me to a mystery that may or may not have anything to do with the lungfish. Occasionally when I’m researching a topic for an episode, I come across something interesting that doesn’t really belong in that episode but which isn’t enough on its own for a full episode. I sometimes spin those into bonus episodes for our Patreon subscribers. That happened recently with our Brantevik eel episode, where some blue river eels took me down a research rabbit hole that had nothing to do with eels. But a mystery animal I only covered in passing in that bonus episode suddenly has new meaning for this one.

The mystery animal is the indus worm, sometimes called the scolex. We don’t know what it was, if anything. It might have been a fable that got repeated and exaggerated over the centuries. It might have been something more akin to disinformation. It might have been both.

We have the story from multiple ancient sources, back to Ctesius’s original account in the fourth century BCE. The story goes that the river Indus, which flows through modern-day China, India, and Pakistan, contained a white worm of enormous size. It was supposed to be around 7 cubits long, or 10 ½ feet, or just over three meters, but it was so big around that a ten-year-old could barely encircle it with their arms, and that’s a straight-up quote from Ctesius only not in ancient Greek. In other words, it was a big fat eel-like creature over ten feet long, white in color. Moreover, it had weird teeth. Ctesias didn’t mention the teeth, but a few hundred years later Aelian said that it had two teeth, square and about eighteen inches long, or 45 cm, which it used to catch and crush animals that it caught at night.

This is an interesting detail that points to an animal with teeth something like a lungfish. But the indus worm was also supposed to drag animals into the water when they came to the edge to drink, which sounds like a crocodile—but the ancient Greeks were familiar with crocodiles and this clearly wasn’t one. The word crocodile comes directly from Greek, in fact. But there’s one more important detail about the indus worm that changes everything.

The indus worm was supposed to be useless except for the oil it produced. Now, all animal fat produces flammable oil, but it has to be rendered first. The indus worm was full of just plain oil. According to the ancient accounts, after an indus worm was killed—not an easy thing to do, apparently, as it required dozens of men with spears and clubs to subdue—it was hung up over a vessel, and the oil allowed to drip into the vessel from the body for a full month. One indus worm would produce about 2 ½ quarts, or almost five liters of oil. The oil was so flammable that only the king of India was allowed to own it, and he used it to level cities. Not only that, but the flame it produced couldn’t be put out unless it was smothered with mud.

This sounds like a petroleum-based flame. It might even refer to Greek fire, a deadly weapon of the ancient world. We don’t know what Greek fire was made of, but it wasn’t an animal-based oil. It could be that rulers who knew the secret of producing unquenchable flame obfuscated the knowledge by telling people the oil came from a vicious animal only found in one distant river. If so, it’s possible that the indus worm wasn’t based on a real animal at all.

I can just hear the conversation that started it all. “Hey, where do you get that oil that sticks to people and burns them up even after they jump in the water?” “Oh, um, it’s really hard to get. Yeah, totally hard. You know those little white worms that sometimes get in figs? Picture one of those that’s like, ten feet long, and it only lives in one river in India…”

Anyway, we have no way of knowing whether the indus worm was a real animal. It actually sounds kind of plausible, though, especially if you assume some of the stories are either exaggerated or confused with other animals. The Indus is a really long river with a lot of unique animal species. It’s possible there was once a lungfish that grew ten feet long and had flattened tooth plates like those of South American and African lungfishes.

Then again, there is another possibility. The rare Indus river dolphin grows to about eight and a half feet long, or 2 ½ meters. I’m probably going to do an entire episode on freshwater dolphins eventually so I won’t go into too much detail about it today, but while young dolphins have pointed teeth, when the dolphin matures its teeth develop into square, flat disks. But the dolphin isn’t white, it’s brown, and no one could look at a dolphin and call it a worm.

But there are other reports of mystery fish in Asia that may be lungfish. This is where I had to stop research for this episode until I ordered, received, and read a book called The Hunt for the Buru by Ralph Izzard. If in doubt, go back to the primary sources whenever possible. Izzard was a foreign correspondent for the London Daily Mail, and in 1948 he and a photographer accompanied explorer Charles Stonor on an expedition to find what they thought might be a living dinosaur or some other reptile. But while many cryptozoologists today think the buru might be a type of monitor lizard, zoologist Karl Shuker suggests the details given in the book sound more like a type of lungfish.

Accounts of the buru were collected in an anthropological study of the Apa Tani tribe in 1945 and ’46. The Apa Tani live in a large valley in northeastern India, in the foothills of the Himalayas, and were an insular people who at the time rarely traveled away from their valley. They’re characterized in The Hunt for the Buru as intelligent and practical, but not especially creative. They have no system of reading or writing, produce no art, and are efficient and knowledgeable rice farmers. The relevant parts of the study are reproduced in The Hunt for the Buru, and I’m happy to report that this was a genuine scholarly study, not a bunch of enthusiastic amateurs asking leading questions. The buru information was only collected incidentally as part of the tribe’s history and traditions, but I suspect mostly because the anthropologists found it interesting. A quick look online for more modern information about the Apa Tani point to them being really nice people. They have a festival celebrating friendship every spring that lasts an entire month. These days they’re much more mainstream but still continue their traditional practices of farming.

According to the Apa Tani, their ancestors migrated to the valley along two rivers, and accounts of their migration match up with actual places with a high degree of accuracy even though the migration took place many centuries ago. In other words, these are people with a detailed oral history, and that’s important when we come to their accounts of the buru.

When they reached the valley, it was largely flooded with a swamp and lake. In the lake was an animal they called the buru. It wasn’t an aggressive animal. It lived in deep water but occasionally came to the surface, stuck its head above water, and made a noise translated as a hoarse bellow. Occasionally a buru would nose through the mud in shallower water, and frequently waved its head from side to side. It didn’t eat fish and was described as living on mud. It was about 4 meters long, or a bit over 13 feet, and was dark blue blotched with white, with a white belly. I’ll go into more details of its appearance in a few minutes.

The Apa Tani drained much of the swamp and lake to create more farmland for rice paddies, and on four occasions, a buru was trapped in a pool of deeper water. The Apa Tani killed the burus trapped this way and buried their bodies, and the location of the buried burus are still known. The Apa Tani reported that there were no more burus in the valley.

In 1947, Charles Stonor was traveling near the Apa Tani’s valley and asked a member of a different tribe if he’d ever heard of the buru. Stonor apparently was both a trained zoologist and had at least some background in anthropology, according to Izzard. To Stonor’s surprise, the man said he not only knew about the buru, but said it lived in a swamp not too far away, called Rilo. Naturally Stonor decided to visit, and when he spoke to the nearby villagers, they said the buru did indeed live in the swamp.

Stonor recorded their accounts of the animal. It lives underwater and only comes to the surface briefly—“every now and again they come up above the surface. When one of them comes up there is a great disturbance and splashing, and the beast comes straight up out of the water, stays for a few moments only, and then disappears down again.” The buru were described as black and white, with a head as large as a bison’s but with a longer snout, and with a pair of small backwards-pointing horns. The buru was only seen in summer, when the swamp floods and becomes a lake. But no one in the Rilo village had ever seen a buru up close.

In early 1948 Izzard heard about the buru from a friend, and approached Stonor to ask if he wanted to undertake a small expedition to look for it. Stonor agreed, and in April 1948 the expedition headed out on the search.

They… didn’t find any burus. Spoiler alert: after months of careful daily watches of the swamp, they decided the buru had possibly once lived in the valley, but was now extinct, and since it had never been an animal the villagers paid much attention to, no one had realized it was gone. This sounds absurd until you realize that the village had only been settled about a decade before. Many trees had been felled, which increased erosion so that the swamp had silted up considerably and was no longer very deep even at full flood. It’s possible that the burus had died due to these changing conditions, especially if they hadn’t been very numerous to start with.

The expedition returned to civilization only to find that rumors of the buru hunt had leaked, and the papers were full of reports of a 90-foot “dinotherium” sighted in the jungle.

I find it interesting that Izzard rejected the idea that the buru was a lungfish, because, he writes, “no known fish would expose itself above water, for no practical purpose, for such a length of time.” Presumably Izzard didn’t realize that lungfish actually use their lungs to breathe air, and that they must surface briefly to do so.

So was the buru reported in the Rilo swamp the same buru that had once lived in the Apa Tani valley? Probably not. Izzard notes that while the two valleys are relatively close to each other, he does point out that they were completely separated by a ridge of mountains. Even if both burus were the same kind of animal, they were probably different subspecies at the very least considering how long the two populations must have been separated.

Let’s return to the Apa Tani buru, since the reports gathered from the mid-1940s anthropological study are clear and detailed compared to the Rilo buru reports.

The Apa Tani buru had limbs, but while some reports called them short legs that somewhat resembled mole forelegs with claws used for digging, one old man stubbornly refused to describe them as legs. The anthropologists found this confusing because they assumed he was talking about a reptile. I’ll quote from the relevant sections of the report. The old man was named Tamar.

“ ‘The buru was long: it had a long tail with flanges on the sides: they lay along it when resting, but were pushed out sideways when the beast was moving: it could twist its tail round and catch anything with it.’ The flanges were demonstrated by holding a piece of paper against a stick. We use the word ‘flange’ for want of a better expression. Tamar described them as pieces fastened on the sides of the tail. …

Q What sort of legs did it have?

A ‘It had no legs: the body was like a snake.’ Tamar then described and demonstrated that the tail flanges were grouped in two pairs, were about 50 cm long, and were as thick as a man’s arm: he added they were used in burrowing. We got the impression that he was trying to convey the meaning that they were appendages, but not limbs in the true sense of the word.”

I wonder if he was trying to explain, through an interpreter, something he himself probably didn’t fully understand, lobed fins. The Australian lungfish’s lobed fins do look like stubby legs with a frill around them that could be taken to be claws.

Tamar also described the buru as a snake-like creature. He said its head was like a snake’s with a long snout and that it had three hard plates on its head that helped it burrow into the mud. And like the other reports, he said it ate mud, not fish or animals.

This sounds a lot like a lungfish, which eats crustaceans and snails it digs out of the mud. Admittedly Tamar also said it had a forked tongue, which is not a lungfish trait. Many cryptozoologists think this forked tongue points to a type of monitor lizard, but while some monitor lizard species do spend a lot of time in the water, notably the widespread Asian monitor lizard, the buru is described as being exclusively aquatic. Monitor lizards also are very lizardy, with large, strong legs. And monitor lizards don’t stay in the mud when a swamp dries up.

To me, all this paints a picture of a large lungfish, blue and white in color, with lobed fins like an Australian lungfish and probably working gills as well as a lung or pair of lungs. It may have aestivated in the mud like African and South American lungfish during the dry season, and during the rainy season when it was spawning, it might have needed to breathe at the surface like the Australian lungfish to give it more oxygen than its gills could manage on their own.

Hopefully someone’s out there looking for burus in other remote swamps of Asia. I can’t do it myself. I’m busy.

There are brief anecdotal reports of possible new species of lungfish in Asia, Africa, and South America, although with very little to go on. But I wouldn’t be one bit surprised if someone discovered another lungfish species in a hard-to-reach swamp one of these days. Those 400-million-year-old fish are survivors.

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

Thanks for listening!

Episode 053: Dragons

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It’s our one-year anniversary! To celebrate, I’ve opened up a Patreon bonus episode for anyone to listen to. Just click the link below and you can listen in your browser:

bonus episode – Salty Animals

This week’s episode is about dragons, specifically dragons of western/English-speaking tradition. Even narrowing it down like that leaves us with a lot of ground to cover! Thanks to Emily whose suggestion of the Komodo dragon as a topic started this whole ball rolling.

A dragon from the game Flight Rising, specifically one of MY dragons. Her name is Lily. She’s so pretty.

The Lambton worm:

A spitting cobra:

A Nile crocodile:

Deinosuchus skeleton and two humans for scale. I stole this off the internet as usual so I don’t know who the people are. They look pretty happy to be in the picture:

St. George and the Dragon (REENACTMENT):

Klagenfurt dragon statue:

A wooly rhino skull:

The star of the show today, the Komodo dragon!

Show transcript:

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

This week let’s celebrate the podcast’s one-year anniversary with a big episode about dragons. Emily suggested komodo dragons as a topic, and then it all just spiraled out of control from there.

But first, a bit of housekeeping. Since it’s our one-year anniversary I’ve unlocked a Patreon episode so that anyone can listen. This one’s about salty animals. There’s a link in the show notes. Just click it and it’ll take you to the page where you can listen on your browser. You don’t need a Patreon login or anything.

Second, I got a polite correction recently from a listener about subspecies. Podbean is being a butt so I can’t actually see the comment, just read it in the email they sent, so I’m not sure who to thank. But they pointed out that “when the subspecies name is the same as the species name, it means it’s the first subspecies formally described, or the nominate subspecies.” In other words, Panthera tigris tigris didn’t get that second tigris because it’s extra tigery, it got it because it was the first tiger subspecies described. Although it is extra tigery.

So now, let’s learn about dragons.

Until the early 13th century or so, the word dragon wasn’t part of the English language. We swiped it from French, which in turn got it from Latin, which took it from Greek. Before the word dragon became a common word, dragon-like creatures were frequently called worms. A worm used to mean any animal that was snakey in shape. Old stories of dragons in English folklore are frequently snakier than modern dragons. For instance, the Lambton worm.

The story goes that a man called John Lambton went fishing one Easter Sunday instead of going to church, and as punishment he caught not fish but a black leech-like creature with nine holes on each side of its head. He flung it into a well in disgust, and joined the crusades to atone for fishing on the Sabbath. But while he was gone, the worm grew enormous. It killed people and livestock, uprooted trees, and even blighted crops with its poisonous breath. It couldn’t be killed, either, because if it was chopped in two, its pieces rejoined.

When John Lambton returned from the crusades seven years later and found out what had happened, he sought the advice of a local wise woman about what to do. Then he covered a suit of armor with sharp spines, and wearing it, lured the worm into the river Wear, where it tried to squeeze him to death. But the spines cut it up into pieces that were swept away by the river so they couldn’t rejoin. The end.

I don’t want to derail the dragon talk too much here, but I’m just going to point out that the sea lamprey has seven little holes behind each eye called branchial openings. It’s also eel-like and can be partially black, and it’s gross. If you want to learn more about it, and about my irrational dislike of this interesting animal, you can go back and listen to episode three.

Anyway, even after English adopted the word dragon, it didn’t mean dragon exactly. It was just a word for a big snake, especially one with mythical attributes or enormous size. But artists the world over are fond of adding wings and legs to reptiles, especially to snakes. Snakes just look so…undecorated. Gradually dragon took on its current meaning, that of a reptile with four legs, possibly a pair of wings, decorative horns and spikes and spines, and the ability to breathe fire. Actual. Fire.

That kind of dragon simply can’t exist except in folklore and fiction. But human creativity aside, many aspects of the dragon, at least the dragons of western tradition, are based on those of real-life animals.

If you’ve listened to episode 12, about the wyvern, the basilisk, and the cockatrice, you may remember the confusion among those terms and what they stand for. Technically all three are types of dragons, since the definition of dragon is actually pretty loose. In that episode, we discussed the king cobra as the possible source of many stories of the basilisk.

The king cobra doesn’t spit venom, but many species of cobra do. While cobra venom won’t hurt you very much if it just touches undamaged skin, it will hurt your eyes if it gets into them. And spitting cobras aim for the eyes. The venom is actually sprayed directly from the cobra’s fangs, which have tiny holes in the front that work sort of like a spray bottle. Some species of cobra can spit venom over six feet, or two meters, and they can also inject venom by biting. Cobra venom can cause blindness if enough gets in the eyes, and it certainly causes eye pain and swelling. Not only that, but a few other species of venomous snake, such as the Mangshan pit viper, sometimes also spit venom.

As far as I’m concerned, a big snake that sprays venom at your eyes is a good basis for the story of a dragon that breathes fire. I’d almost rather deal with a firebreather, to be honest, because I know to stop, drop, and roll if I catch on fire. Be safe, kids. This has been a public service announcement.

Crocodiles have undoubtedly influenced dragon mythology. In fact, so many common dragon traits are present in crocodiles that if you discount the wings and firebreathing, crocodiles basically are dragons. The biggest crocodile living today is the saltwater crocodile, which can grow over 20 feet long, or 6 meters, and which lives in southeast Asia, eastern India, and northern Australia. The second biggest crocodile is the Nile crocodile, which can grow nearly as long, and which lives throughout much of Africa around rivers, lakes, and swamps. Male saltwater crocodiles are typically larger than females, while female Nile crocodiles are typically larger than males.

While crocodiles look like big lizards, they’re actually more closely related to birds and dinosaurs. They can also live a long time, occasionally over a hundred years. All crocodiles are good swimmers with webbed feet that help them change directions quickly. They can also run pretty fast out of water. A crocodile’s back is heavily armored with thick scales and osteoderms, or scutes, which are bony deposits in the skin. Crocodiles have long jaws studded with 80 teeth, and if a croc loses a tooth, another grows in its place. It can just keep replacing its teeth up to 50 times. It has good night vision, a good sense of smell, good hearing, and special sensory pits on its jaws that allow a croc to hunt and escape danger even in complete darkness. A croc’s stomach contains acid that would make even the bearded vulture envious, so it has no problem digesting bones, hooves, and horns efficiently, a good thing since Crocodiles usually swallow their prey whole. And crocodiles have the strongest bite of any living animal, stronger even than a great white shark.

Of course, there used to be bigger crocodiles. Do you want to learn about gigantic extinct crocodiles? OF COURSE YOU DO, that is basically why we’re all here.

Okay, so, there used to be a 35-foot, or almost 11-meter-long crocodile called Deinosuchus that lived around 75 million years ago in what is now North America. It basically looked like a modern crocodile, but its rear teeth were shorter and blunter than its front teeth. They were adapted to crush its prey rather than bite through it, probably because with a bite force that was probably stronger than a T. rex’s, it didn’t want to accidentally bite a big chunk out of the dinosaurs it ate. Yeah. It ate dinosaurs.

So crocodiles probably did a lot to inspire dragon folklore. There’s still a lot of mythology wrapped around the crocodile today, for that matter. You know those little birds that are supposed to clean crocodile teeth? Not actually a thing. I’ve lived my whole life thinking that was pretty neat, only to find it’s a myth.

Sometimes in spring a croc will lie in the water with sticks on its snout. When a bird flies down to pick up a stick for nesting, the crocodile will grab the bird and eat it. This is a real thing that happens, not a myth. Crocodiles are actually pretty smart. And sometimes they hunt in packs.

One of the most famous traditional dragon stories in the English language is that of St. George and the Dragon, which probably originated from stories brought back to Britain during the Crusades. The story became especially popular in the 13th century and there are many versions.

According to the story, a venomous dragon lived in a pond near a city, and had poisoned not only its pond, but the entire countryside. To keep the dragon from approaching the city, the people had to feed it their own children. Each day the people held a terrible lottery to see who had to send one of their children to the pond for the dragon to eat. One day the princess was chosen, and despite all the king’s gold and silver he had to send his daughter to be eaten by the dragon.

Fortunately for her, St. George just happened to be riding by. The dragon emerged from its pond and St. George thought, oh no, we’re not having any of that, and charged it. He wounded it with his lance, then had the princess give him her girdle to use as a collar. A girdle in this case was something between a decorative belt and a ribbon tied around the waist. As soon as St. George tied the girdle around the dragon’s neck, it became meek as a puppy and followed him back to the city.

Naturally, everyone was terrified, but St. George said he would kill the dragon if the king and his people would convert to Christianity. They did, he did, and that was the end of the dragon.

While crocodiles and big snakes undoubtedly strongly influenced dragon lore, something else did too. There’s a reason dragons are so often supposed to live in caves, for instance. Caves are good places to find fossils of huge extinct animals.

In Klagenfurt in Austria there’s a monument of a dragon, called the lindorm or lindwurm, that was erected in 1593. It still stands today, together with a statue of Hercules that was added almost 40 years later. The dragon statue is based on a story of the region. The story goes that a dragon lived near the lake and on foggy days would leap out of the fog and attack people. Sometimes people could hear its roaring over the noise of the river. Finally the duke had a tower built and filled it with brave knights. They fastened a barbed chain to a collar on a bull, and when the dragon came and swallowed the bull, the chain caught in its throat and tethered it to the tower. The knights came out and killed the dragon.

The original story probably dates to around the 12th century, but it was given new life in 1335 when a skull was found in a local gravel pit. It was clearly a dragon skull and in fact it’s still on display in a local museum. The monument’s artist based the shape of the dragon’s head on the skull. In 1935 the skull was identified as that of a wooly rhinoceros.

Other dragon stories probably started when someone saw huge fossils they couldn’t identify. Dragons, after all, can look like just about anything. Stories of benevolent dragons living on Mount Pilatus in Switzerland may have started by pterodactyl fossils that are frequently found in the area. In 1421 a farmer saw a dragon flying to the mountain, and it was so close to him that the farmer fainted. When he woke, he found a stone left for him by the dragon, which had healing properties. The dragonstone is in a local museum these days and has been identified as a meteorite.

It occurs to me that if one were rich, and by one I mean me, one could take a dragon tour through Europe and visit all these awesome monuments and museums. That would be part of my expedition to search for the tatzelwurm in the Alps.

We’ll finish up at the animal I mentioned at the beginning of the episode, the Komodo dragon. While in many respects the Komodo dragon is a real-life dragon, it probably didn’t influence traditional dragon stories in the western world because no one in Europe knew anything about it until 1910. It only lives on five small islands, notably Komodo, but it’s also found on the island of Flores where the Homo floresiensis remains were found.

There were rumors for years of a type of land crocodile found on Komodo. Dutch sailors said it actually breathed fire and could even fly. In 1910, a Dutch Colonial Administration official from Flores took some soldiers to Komodo and searched for the dragon. They shot one, and Peter Ouwens, director of the Zoological Museum in Bogor, Java, hired hunters who killed two more. Ouwens studied the lizards and published a formal description in 1912. In direct contrast to many governments of the time, who were apparently trying to drive as many species to extinction as possible, in 1915 the Dutch government listed the Komodo dragon as protected.

Keep in mind that at this time, people were completely bonkers about dinosaurs and other megafauna. The Komodo dragon got incredibly famous in a very short amount of time. A 1926 scientific expedition that brought back two live dragons and twelve preserved ones actually inspired the 1933 movie King Kong. Since Komodo dragons displayed in zoos proved to be huge draws, but didn’t survive long in captivity back then, if the dragon hadn’t already been protected it probably would have been driven to extinction by collectors capturing them for zoos and killing them to sell to museums as taxidermied specimens.

Researchers used to think that the Komodo dragon, which is a type of monitor lizard, demonstrated island gigantism, where some species that are typically not so big grow larger when a population is restricted to an island. Island dwarfism is its opposite, where big animals like elephants evolve to become smaller in an island habitat. But many species of monitor lizard are large even though they don’t live on islands, and it turns out that a close relative of the Komodo dragon lived in Australia until around 50,000 years ago. In fact, the first aboriginal settlers of Australia might have encountered it.

It was called Megalania and it was the largest straight-up lizard, as opposed to dinosaur, that’s ever been found. While we don’t have any complete skeletons, some researchers estimate it grew to around 18 feet long, or 5.5 meters, although older estimates had it up to 23 feet long, or 7 meters. Either way, it was much bigger than the Komodo dragon, which can grow just over ten feet long, or more than 3 meters.

Like the crocodile, the Komodo dragon’s skin contains osteoderms. It almost looks like it’s covered with tiny spines up close. Also like the crocodile, it grows new teeth when it loses old ones, which frankly is something I wish mammals could do because how useful would that be? It can run faster than a crocodile, can swim and dive well when it needs to although it prefers to stay on land, and when it’s young it can climb trees. Older dragons are too heavy to climb trees, but an adult can stand on its hind legs using its tail as a prop. It likes to dig burrows to sleep in, and females may dig nesting burrows 30 feet long, or 9 meters.

The Komodo dragon eats anything, from carrion to baby Komodo dragons to humans, but it especially likes deer and wild pigs. Its sense of smell is so acute, it can smell a dying animal almost six miles away, or 9 ½ km. It will swallow smaller prey whole but will tear chunks off of bigger carcasses.

We’re still learning about the Komodo dragon. For a long time researchers thought it had a nasty dirty mouth full of rotten meat, which infected its prey with bacteria when bitten. But it turns out that the Komodo dragon is actually venomous. This is still somewhat controversial, since the Komodo dragon’s saliva does contain 57 strains of bacteria and some researchers think that’s more toxic than its venom. Whatever the case, you do not want to be bitten by a Komodo dragon.

It’s primarily an ambush predator, and when it attacks an animal, it gives it a bite with its huge serrated teeth. If the animal gets away, no problem. The dragon’s venom contains anticoagulants so it will probably die of blood loss. As for the dragon itself, its blood actually contains antimicrobial proteins. Researchers hope to develop new antibiotics from the proteins.

Komodo dragon eggs are big, about the size of grapefruits. The mother dragon guards her nest until the babies hatch, and some researchers have observed mothers defending their babies for short periods after they hatch. Baby dragons mostly live in trees and eat insects, lizards, birds’ eggs, and other small prey. If they want to approach a grown-up dragon’s kill to eat some of it, a baby will roll around in poop first or in the stinky parts of the dead animal’s guts so the adult dragons won’t eat the baby. Captive female dragons occasionally lay fertile eggs even though they’ve never mated, a process known as parthenogesis.

Komodo dragons look dumb. They’re probably not exactly geniuses even compared to crocodiles. But dragons kept in captivity sometimes play with items in their enclosures, which is pretty neat. If even a Komodo dragon can take time out of its busy schedule to play, you can too.

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

Thanks for listening!

Episode 051: The Carolina Parakeet and the Elephant Bird

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This week’s episode is about the Carolina parakeet, a cheerful, pretty bird that was once common in the central and eastern United States but which has been extinct for a century. Thanks to Maureen for the suggestion! I’ve paired it with the elephant bird, a gigantic extinct bird that we don’t know much about except for its enormous eggs.

The Carolina parakeet, deceased:

An ex-parrot next to an ex-passenger pigeon:

A still from the 1937? Nelson video:

The 2014 mystery parakeet photo:

An elephant bird, an elephant bird egg, and Sir David Attenborough (right):

Further Reading/Watching:

Here’s a close evaluation of the Nelson video taken in the late 1930s, supposedly in the Okefenokee Swamp.

I can’t get the Nelson video to embed properly, so here’s a link to it. You’ll need to scroll down to the bottom of the page for a decent-sized version that will play.

Show transcript:

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

This week’s episode is about two birds, one small and one really big, and both extinct. Probably.

First, let’s learn about the Carolina parakeet, a suggestion by listener Maureen. It was a type of small parrot that was common throughout a big part of the United States, as far west as Nebraska and parts of Colorado and as far north as New York, and as far south as Florida and around the Gulf of Mexico. It had a yellow and orange head and a green body with some yellow markings, and was about the size of a mourning dove or a passenger pigeon.

This story of extinction mirrors that of the passenger pigeon in many ways. The Carolina parakeet lived in forests and swamps in big, noisy flocks and ate fruit and seeds. But when European settlers moved in, turning forests into farmland and shooting birds that were considered pests, its numbers started to decline. In addition, the bird was frequently captured for sale in the pet trade and hunted for its feathers, which were used to decorate hats. Part of the reason it was so easy to kill was that if a wounded bird’s cries were heard by other Carolina parakeets—and they probably would hear it, since these birds were loud, with calls carrying up to two miles—the whole flock would come flying out to help the wounded bird.

By 1860 the Carolina parakeet was rare anywhere except the swamps of central Florida, and by 1904 it was extinct in the wild. The last captive bird died in the Cincinnati Zoo in 1918, which was not only the same zoo where the last passenger pigeon died in 1914, it was the same cage. It was declared extinct in 1939.

We don’t know a lot about the Carolina parakeet even though it survived into the 20th century because no one made any particular study of the bird. John Audubon painted it and made some notes, and we have a lot of skins, skeletons, and some stuffed specimens, but that’s about it. There were two subspecies, one that lived to the east of the Appalachian mountain range, and one that lived to the west, that went extinct sooner than the eastern subspecies and was more bluish-green than green.

One interesting thing that Audubon noted is that cats that killed and ate Carolina parakeets died. The bird ate a lot of cockleburs, and the cocklebur’s seed is poisonous—so much so that livestock die from eating them. If you listened to episode 31, venomous animals, you may remember the Africa spur-winged goose that eats toxic blister beetles, collects the toxin in its tissues, and is therefore poisonous to eat. It’s probable that the Carolina parakeet did the same with cocklebur toxins.

Sightings of the bird in the wild occurred through the 1920s and 30s. A whole flock of some 30 birds was spotted in Florida in 1920, and in 1926 three nesting pairs were seen in Okeechobee County, Florida by the Curator of Birds at Florida University, Charles Doe. Doe was so excited to find these supposedly extinct birds that he ROBBED ALL THREE PAIRS OF THEIR EGGS. Because that man was an idiot and he will go down in history as an idiot. Charles E. Doe, Idiot, it probably says on his tombstone. His egg-shaped tombstone, probably.

In the mid-1930s ornithologist Alexander Sprunt Jr collected a number of sightings of Carolina parakeets in the Santee Swamp in South Carolina. Numerous trained bird wardens and ornithologists saw the birds, but it didn’t matter. In 1938 the Santee River was dammed and a power plant built, which radically changed the area ecosystem, and much of the surrounding forest was cut down and the swampland drained during the construction process. No one has reported any parakeet sightings since then.

Of course, the southeast still has lots of swampland, some of it all but impenetrable. The Okefenokee Swamp in Georgia and Florida is close to half a million acres, or more than 1700 square kilometers, and most of that area has been a national wildlife refuge since 1974. In 1937 or a little after, someone shot about 50 seconds of color film footage of three green birds in the Okefenokee. The footage is usually attributed to a man named Oren, or Orsen, Stemville.

In the early 1950s an Audubon lecturer named Dee Jay Nelson bought an old film camera from a boat operator in the Okefenokee Swamp. The box it came in contained eight rolls of processed 16mm film, but Nelson didn’t actually view those rolls for about 15 years. One roll contained footage of alligators and toads native to the Okefenokee, and in between those was some strange footage of three green birds.

Roger Tory Peterson, a member of the American Ornithologists’ Union, got a copy of the film and presented it to the society for analysis in 1969. There was no consensus as to whether the birds were feral pet parakeets of some kind or Carolina parakeets. Peterson misplaced his copy of the film and when Nelson was contacted by the society in 1979, he said he had lost the original. But in 2005 the copy turned up in Peterson’s effects after he died. At that point the Ornithologists’ Union analyzed the film again and concluded that not only are the birds not Carolina parakeets, they appear to have been artificially colored to look like Carolina parakeets. In other words, it was a hoax—and not even a very good one. It’s possible that only one of the birds was even real; the others were probably taxidermied birds or models. Nelson’s story about how he found the footage is fishy anyway. In the 1960s Nelson was a screen-tour lecturer from Montana, so he may have shot the footage himself to illustrate some project that never got off the ground.

The 2005 analysis of the footage was thorough. The society even brought in botanists to find out what kind of tree is shown in the film, but they were unable to identify it and said that the Spanish moss draped on the branches appears to have been placed there instead of growing there naturally. I’ll put a link in the show notes to the society’s close notation of the footage, practically frame by frame. The film is archived with the Cornell University’s Laboratory of Ornithology, and I’ll include a link to the video too.

The problem with sightings is that the green parakeet, a species native to Central America as far north as the southern tip of Texas, and the red-masked parakeet from Ecuador and Peru, look similar to the Carolina parakeet and have been pets in the United States for a long time, as have many other parrot species. In Florida in particular, escaped parrots sometimes survive and band together in breeding colonies, and by the 1920s had already begun to do so. So if the Nelson footage isn’t a hoax, it might be mistaken identity.

While I’m pretty nearly certain that the Carolina parakeet really is extinct, if it still manages to hang on in the depths of the Okefenokee swamp or elsewhere, anyone who’s observed it might assume they’ve only seen a red-masked parakeet or something.

On April 1, 2009 someone posted an article that looked like a press release from Cornell University about the discovery of a population of Carolina Parakeet in northern Honduras. It was an April fool’s joke, but it was so convincing that people still claim it’s real. I really hate April fool’s, by the way.

In January 2014, someone posted an interesting picture to a bird forum, saying her son took the picture at their home in southern Georgia in 2010 and asking what kind of parrot it was. The bird’s a dead ringer for a Carolina parakeet sitting in an apple tree. The poster deleted the thread later, upset at being accused of posting a hoaxed picture. This being the internet, no one can agree on whether the picture is real or shopped. It looks real to me, but while it might be a young yellow-headed Amazon parrot, the red cheeks aren’t a yellow-headed trait. So it’s a mystery.

From this small, brightly colored bird we go to a gigantic one. The elephant bird stood about ten feet tall head to toe, or 3 m, and while it looks superficially like an ostrich, it was more closely related to the tiny kiwi of New Zealand. But the elephant bird only lived in Madagascar.

It’s possible that stories about the roc, an eagle so big it could pick up elephants, were actually garbled stories about the elephant bird. That’s where the name elephant bird comes from, incidentally. The real life elephant bird probably became the fabled roc not from sightings of the bird but from its eggs. The eggs were enormous, the largest bird egg known and possibly the largest egg ever known, some over a foot long or about 34 cm, and big enough to hold over two gallons of liquid, or seven and a half liters. We’re getting close to watermelon sized here.

In 1930, in the southernmost point of Western Australia, two boys were playing along the beach and discovered a gigantic egg buried in a sand dune. They took it home, where no one had any idea what bird might have laid it. It was twice the size of an ostrich egg. Eventually it was given to the Western Australia Museum, and in 1962 a naturalist examined it and identified it as the egg of an elephant bird. Another elephant bird egg was found in western Australia by three children in 1992. But what were they doing in Australia? Elephant birds can’t fly, were never native to Australia or anywhere else except Madagascar, and anyway by 1930 they were certainly extinct.

Well, eggs can float, especially in saltwater and especially if the embryo inside has died, as would happen if the egg was washed out of its nest and into cold water. The elephant bird liked to lay its eggs in sand along the beach or rivers. Sometimes they would be washed out to sea. People who found elephant bird eggs without knowing what kind of enormous bird they would hatch into would naturally tell stories about them, like the roc. And even now, when there are no elephant birds around to lay new eggs, intact eggs are still occasionally found. The shells of elephant bird eggs were as much as 4 mm thick, which doesn’t sound like much but is way thicker than any other egg shell. That’s over an eighth of an inch thick.

So these were big, tough eggs that weren’t easily destroyed. Moreover, the egg found in Australia in 1992 was dated to 2,000 years old and was found in deposits of sand that had been laid down a few thousand years ago too. Both eggs had been in place for millennia until those meddling kids dug them up.

In 1974 a King Penguin egg was found floating near the beach very near where the 1930 elephant bird egg was found, having drifted some 1200 miles, or 2,000 km, in only a matter of weeks. In 1991 another King Penguin egg was found in the same region. This one was covered in barnacles and algae, but both were easily removed without damaging the egg. And in the early 1990s, a man working on a dredge in the Timor Sea, which is part of the Indian Ocean, spotted an ostrich egg in the water and retrieved it. It was so heavily weighted down with algae that it wasn’t bobbing along at the surface, but it was still floating under the surface and was intact. Any barnacles that had grown on the elephant bird eggs would have been sandblasted off by wind once the eggs were beached. The 1930 egg had one surface polished smooth from exposure to wind.

The elephant bird ate plants, probably nuts and fruit. Some researchers think the fruit of some rare species of palm trees on Madagascar were eaten and dispersed by the elephant bird. It had muscular legs like an ostrich but was so heavy, it probably couldn’t run very fast.

We’re not sure when the elephant bird went extinct. Some egg shells have been dated to about 1,000 years ago and that seems to be the latest signs of elephant birds. But as late as the 17th century native people from Madagascar were adamant that it still lived in hard-to-travel swamps.

We do have a pretty good idea of why the elephant bird went extinct, though. The eggshells were used as buckets and bowls, and archaeological studies have found plenty of charred shells in cooking fires. One elephant bird egg could feed an entire family. The adult birds were also hunted and eaten. Not only that, when European settlers decided they’d like to live in Madagascar now, thanks very much, you native people can just shift over and give us all the good land, deforestation and overhunting combined to finish off the elephant bird forever.

Like other recently extinct animals, the elephant bird is a good candidate for de-extinction once cloning technology is perfected. But if we do get the elephant bird back, we have to promise not to eat all its eggs.

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

Thanks for listening!

Episode 050: Tallest Animals

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We’re discovering which animals are the tallest this week! This episode includes our first dinosaur!

Sauroposeidon proteles:

Giraffes:

Bop bop bop have at thee!

Paraceratherium (I couldn’t find one that I liked so I drew one, along with a giraffe and ostrich to scale):

Ostrich running:

I SAID DON’T @ ME

A fine day at the ostrich races. I could not make this stuff up if I tried:

Show transcript:

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

This week we’re looking at tall animals. Is the giraffe the tallest mammal that’s ever lived? Is the ostrich the tallest bird? And what about tall dinosaurs?

I don’t talk about dinosaurs much in this podcast because there are so many good podcasts devoted specifically to dinosaurs. I recommend I Know Dino. It’s family friendly and goes over the latest dinosaur news without talking down to listeners or dumbing down the information.

Four-footed animals are usually measured at the shoulder, since some animals hold their heads low, like bison, while others hold their heads high, like horses. But we’re talking about tall animals today, and that includes animals with long necks. So the measurements here are all from head to toe, with the head and neck held in its natural standing position.

Let’s start with the real biggie, the tallest dinosaur ever found.

In 1994 a guy named Bobby Cross noticed some fossils weathering out of the ground at the Oklahoma correctional facility where he worked as a dog trainer. As he always did when he found fossils, he called the Oklahoma Museum of Natural History. They sent a team to take a look. The team found four vertebrae, but they were just so big—around four feet long each, or 120 cm—that at first they thought they must be fossilized tree trunks.

Sauroposeidon proteles was probably closely related to Brachiosaurus, but was even bigger and taller. Sauroposeidon stood 60 feet tall, or 18 meters, and its neck alone was 39 feet long, or 12 meters. Its body and legs were relatively short and stocky. We don’t have a complete skeleton, just the four vertebrae found in southeastern Oklahoma, and a few vertebrae from two other individuals found in Montana and Texas. A trail of giant footprints in Texas may be a Sauroposeidon track too. But for sauropods, neck vertebrae are the most valuable fossils because they tell so much about the animal.

Sauroposeidon’s neck bones were massive, but they were lighter than they look due to tiny air sacs in the bones, like those in bird bones. The air sacs in bird bones actually contain air that flows through the lungs, called pneumatic bones, which provides the bird with more oxygen. A CT scan of the Sauroposeidon fossils—at least the portions of the fossils that would actually fit in the CT scanner—revealed that sauroposeidon’s vertebrae were constructed in the same way that bird bones are. We know that pterosaurs and theropods had pneumatic bones, so it’s not too surprising that at least some sauropods did too.

Sauroposeidon lived around 110 million years ago, during the Mesozoic era, specifically during the early to mid Cretaceous. The sea level was much higher then than it is now, so Sauroposeidon lived near the coast. It ate plants, and like many birds, it also swallowed stones to help it digest those plants, called gastroliths. Paleontologists have found lots of sauropod gastroliths associated with fossil animals. Unlike mammals, which chew their food before swallowing, sauropods swallowed it whole and the plant material was broken up in a stomach or gizzard-like structure. That’s why its head is so small relative to its body, and how it could eat enough plants to keep such an enormous body going. It probably ate literally a ton of food every single day.

We know a lot about sauropods, and since sauroposeidon appears to be structurally typical of other sauropods, just really big, it’s a safe bet to assume it was like other sauropods in many ways. It probably nested in groups and laid about two dozen eggs at a time in big nests on the ground. We don’t have any sauroposeidon eggs, but they probably wouldn’t have been all that big, maybe about the size of a football. Babies would have grown rapidly and were full grown in ten to twenty years. Sauroposeidon migrated in herds throughout the year, traveling from nesting grounds to new grazing grounds. While it lived near the ocean, it would have had to be careful about walking on soft ground. An animal that tall and heavy can get mired in mud easily. Paleontologists have actually found fossils of sauropods that died standing up, unable to climb out of a muddy hole after sinking in soft ground.

Giraffes are the tallest living animals today, with the tallest recorded giraffe, a male, measuring 19.3 feet, or 5.88 meters. That’s pretty darn tall, about 1/3 the height of sauroposeidon. Giraffes are related to deer and cattle, and live in the savannahs and forests of Africa, where they eat tree leaves that are much too high off the ground for other animals to reach. Female giraffes and their young make up loose groups, while males form groups of their own. While giraffes can kick hard enough to kill lions, when males fight over females, they use their necks. A male will swing its head at another male, and the two will tussle back and forth bopping necks together. As a result, male giraffes have thicker, stronger necks than females. Males are also usually taller than females.

The giraffe not only has a long neck and long legs, it has a long tongue that it uses to grab leaves that are juuuust too far away. The tongue is about 18 inches long, or 45 cm. A giraffe at Knoxville Zoo licked my hair once. The giraffe’s upper lip is also prehensile, and is hairy as a protection from thorns. Because of all the thorns it encounters, giraffe skin is surprisingly tough. The giraffe has large eyes that give it good vision, and it also has keen hearing and smell. It can close its nostrils to protect them from dust, sand, insects, and—you guessed it—thorns. So many thorns. And giraffe fur contains natural parasite repellents, which also makes giraffes smell funny.

All this is pretty awesome, but we’re not done with giraffe awesomeness. Giraffes have skin-covered horns called ossicones. Females and males both have ossicones, although males also have a median lump at the front of the skull that’s not exactly an ossicone but is sort of like one. Some females also have this median lump. Ossicones are made of cartilage that has ossified, or turned boney, and they’re covered in skin and hair, although since males use their ossicones in necking fights, they tend to rub all the hair off and have bald ossicones.

The only other animal alive today that has ossicones is the okapi, a close relative of the giraffe, but giraffe ancestors once had all kinds of weird ossicones. Xenokeryx amidalae, for instance, which lived about 16 million years ago in what is now Spain, had two ossicones over its eyes, and a third sticking up from the back of its head that was T-shaped. The name amidalae comes from the character Padme Amidala in Star Wars: The Phantom Menace, if you remember that weirdly shaped headdress she wore.

Because giraffes are so tall, they have some physical adaptations that are unique among mammals living today. A giraffe has the same number of neck bones as all other mammals except sloths and manatees, which are weird, but the vertebrae are much longer than in other mammals, almost a foot long, or 28 cm. The giraffe can also tilt its head right back until it’s just about in line with the back of the neck. I’m picturing everyone listening tilting their heads back right now, and hopefully you notice how the back of your neck curves when you look up. Also, please don’t wreck your car because you’re looking up while driving. The giraffe’s circulatory system is really unusual. Its heart is enormous and beats around 150 times per minute. The jugular veins, which are the big veins that carry blood up the neck to the brain, have valves that keep blood from running backwards when a giraffe lowers its head to drink.

Giraffes can walk, and giraffes can run, but they don’t have any other gaits. They can’t trot or canter, for instance. Even humans have more than two gaits, because we can skip. Despite its height, a giraffe can really move. It can run over 30 miles per hour, or about 50 km per hour, and keep it up for several miles. It has cloven hooves. Because a giraffe’s body is so heavy and its legs so long and thin, it has specialized ligament structures in its legs that keep them from collapsing. Horses also have this structure, which also helps the animal sleep while standing.

Oh, and the giraffe doesn’t eat leaves all the time. It spends a lot of the day just standing around chewing its cud.

There used to be a mammal that stood almost as tall as the giraffe at the shoulder. Paraceratherium orgosensis went extinct around 23 million years ago, and it’s not even related to the giraffe. It’s a member of the rhinoceros family. Like sauroposeidon, we don’t have a complete skeleton of paraceratherium, so its size is an estimate based on the proportions of closely related animals whose sizes we do know. It probably stood 18 feet high at the shoulder, or 5.5 meters, and while its neck was probably around 7 feet long, or a little over 2 meters, it probably held it forward like a rhino instead of up like a giraffe, so it didn’t add much to the animal’s overall height.

In episode 32 we learned about the giant moa, a flightless bird that once lived in New Zealand. It was probably the tallest bird that ever lived, with big females 12 feet tall, or 3.6 meters. But the tallest living bird is the ostrich. It also lives in Africa and is famous for being flightless and for being able to run really fast. In fact, it’s not only the tallest bird alive, it’s the fastest. It can run over 40 miles per hour, or about 70 km per hour, and it uses its large wings as rudders and even to help it brake. With its head raised, a big ostrich can be nine feet tall, or 2.8 meters.

There are a lot of differences between ostriches and most other birds. Most birds have four toes, for instance. The ostrich has two, one large toe with a hoof-like nail, and a smaller outer toe with no nail at all. All other living birds secrete urine and feces together, but the ostrich secretes them separately the way mammals do. And while most male birds don’t have a penis, the male ostrich does. And the ostrich has a double kneecap. Not only is that unique to birds, it’s unique to everything. No other animal known, living or extinct, has a double kneecap. Researchers have no idea what it’s for, although one hypothesis is that it allows a running ostrich to extend its legs farther, and another hypothesis is that it might protect tendons in the bird’s leg.

The ostrich eats plants, seeds, and sometimes insects. Like Sauroposeidon and many other dinosaurs and birds, the ostrich swallows small rocks and pebbles to help digest its food in its gizzard. The gizzard contracts, smashing the gastroliths and plants together to help break up the plant material the way mammals would chew it.

Ostrich eggs are the biggest laid by any living bird, about six inches long, or 15 cm. Females lay their eggs in a communal nest.

Ostriches are farmed like big chickens, for their feathers, meat, and skin for leather. Ostriches are also sometimes ridden and raced with special saddles and bridles. But ostriches aren’t easy birds to manage. They can be aggressive, and they can kill a human with one kick.

To wrap things back around to dinosaurs, some researchers think many fast-running dinosaurs used their feathered forelimbs the way ostriches use their wings, to help maneuver and possibly to help keep unfeathered portions of the body warm at night. During the day, when it’s hot, ostriches keep their wings raised so that their unfeathered upper legs can release heat into the atmosphere, but at night they cover their upper legs to retain heat. It’s just another link between birds and their long-distant ancestors, the dinosaurs.

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

Thanks for listening!

Episode 049: The Brantevik Eel and Friends

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This week’s episode is about some interesting eels, including the Brantevik eel.

A European eel:

A leptocephalus, aka an eel larva:

A moray eel. It has those jaws you can see and another set of jaws in its throat:

Episode transcript:

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

This week, we’re going to learn about the Brantevik eel and some other eels, including an eel mystery.

The Brantevik eel is an individual European eel, not a separate species. Its friends knew it as Åle, which I’ve probably misprounounced, so I’m nicknaming it Ollie. So what’s so interesting about Ollie the eel?

First, let’s learn a little bit about the European eel in general to give some background. It’s endangered these days due to overfishing, pollution, and other factors, but it used to be incredibly common. It lives throughout Europe, from the Mediterranean to Iceland, and has been a popular food for centuries.

The European eel hatches in the ocean into a larval stage that looks sort of like a transparent flat tadpole, shaped roughly like a leaf. Over the next six months to three years, the larvae swim through the ocean currents, closer and closer to Europe, feeding on microscopic jellyfish and plankton. Toward the end of this journey, they grow into their next phase, where they resemble eels instead of tadpoles, but are mostly transparent. They’re called glass eels at this point. The glass eels make their way into rivers and other estuaries and slowly migrate upstream. Once a glass eel is in a good environment it metamorphoses again into an elver, which is basically a small eel. As it grows it gains more pigment until it’s called a yellow eel. Over the next decade or two it grows and matures, until it reaches its adult length—anywhere from two to five feet, or 60 cm to 1.5 meters. When it’s fully mature, its belly turns white and its sides silver, which is why it’s called a silver eel at this stage. Silver eels migrate more than 4,000 miles, or 6500 km, back to the Sargasso Sea to spawn, lay eggs, and die.

One interesting thing about the European eel is that during a lot of its life, it has no gender. Its gender is determined only when it grows into a yellow eel, and then it’s mostly determined by environmental factors, not genetics.

Until the late 19th century, everyone thought these different stages—larva, glass eel, elver, yellow eel, and silver eel—were all separate animals. No one knew how or even if eels reproduced. The ancient Greeks thought eels were a type of worm that appeared spontaneously from rotting vegetation. Some people thought eels mated with snakes or some types of fish. By the 1950s the eel’s life cycle was more or less understood, but many researchers thought the European eels never made it to the Sargasso Sea to spawn. It was just too far, so they thought the eels that arrived in Europe were all larvae of the American eel, which is almost identical in appearance to the European eel. The Sargasso Sea is off the coast of the Bahamas, so the American eel doesn’t have nearly as far to travel. These days we know from DNA studies that the American and European eels are different species. The European eel is just a world-class swimmer.

European eels are nocturnal and may live in fresh water, brackish water, or sometimes they remain in the ocean and live in salt water, generally in harbors and shallows. They eat anything they can catch, from fish to crustaceans, from insect larvae to dead things, and on wet nights they’ll sometimes emerge from the water and slide around on land eating worms and slugs. Many populations don’t eat at all during the winter.

Now, back to the Brantevik eel. Brantevik is a tiny fishing village in Sweden. In 1859, an eight-year-old boy named Samuel Nilsson caught an eel and released it into his family’s well to eat insect larvae and other pests. This was a common practice at the time when water wasn’t treated, so the fewer creepy-crawlies in the water, the better.

And there the eel stayed. Ollie got famous over the years, at least in Sweden. Its 100th well anniversary was celebrated in 1959, and children’s books and even movies featured it. But in summer of 2014, Ollie died. Its well is now on the property of Tomas Kjellman, whose family bought the cottage and its well in 1962. Everyone knew about the resident eel, which the family treated as something of a pet. In fact, they discovered it was dead when they opened the well’s cover to show the eel to some visiting friends.

Ollie’s remains were removed from the well and shoved in the family’s freezer, and later sent to be analyzed at the Swedish University of Agricultural Science’s Institute of Freshwater Research. That analysis confirmed that Ollie was over 150 years old.

In the wild, European eels don’t usually live longer than twenty years, and ten years is more likely. But in captivity, where eels don’t spawn, they can live a long time. A female European eel named Putte lived over 85 years in an aquarium at Halsinborgs Museum in Sweden.

What most people don’t know is that Ollie wasn’t alone. Another eel still lives in the well and is doing just fine, but it’s younger, only about 110 years old.

The larvae of European eels are small, only about three inches at the most, or 7.5 cm. Even conger eel larvae are small, only 4 inches long, or 10 cm, and conger eels can grow 10 feet long, or 3 meters. But on January 31, 1930, a Danish research ship caught an eel larva 900 feet deep off the coast of South Africa—and that larva was six feet 1.5 inches long, or 1.85 meters.

Scientists boggled at the thought that this six-foot eel larva might grow into an eel more than 50 feet long, or 15 meters, raising the very real possibility that this unknown eel might be the basis of many sea serpent sightings.

The larva was preserved and has been studied extensively. In 1958, a similar eel larva was caught off New Zealand. It and the 1930 specimen were determined to belong to the same species, which was named Leptocephalus giganteus. Leptocephalus, incidentally, is a catchall genus for all eel larvae, which can be extremely hard to tell apart.

In 1966 two more of the larvae were discovered in the stomach of a western Atlantic lancet fish. They were much smaller than the others, though—only four inches and eleven inches long, or 10 cm and 28 cm. Dr. David G. Smith, an ichthyologist at Miami University, determined that the eel larvae were actually not true eels at all, but larvae of a spiny eel. Deep-sea spiny eels are fish that look like eels but they’re not closely related. And while spiny eels do have a larval form that resembles that of a true eel, they’re much different in one important way. Spiny eel larvae grow larger than the adults, then shrink when they develop into their mature form.

So the six-foot eel larvae, if it had lived, would have eventually developed into a spiny eel no more than six feet long itself at the most, and probably shorter.

More recent research has called Dr. Smith’s findings into question, and many scientists today consider L. giganteus to be the larvae of a short-tailed eel, which is a true eel—but not a type that grows much larger than its larvae. So either way, the adult form would probably not be much longer than a conger eel.

But…we still don’t have an adult. So there’s still a possibility that a very big deep-living marine eel is swimming around in the world’s oceans right now.

The longest known eel is the slender giant moray, which can reach 13 feet in length, or 4 meters. Morays are interesting eels for sure. They live in the ocean, especially around coral reefs, and have two sets of jaws, their regular jaws with lots of hooked teeth, and a second set in the throat that are called pharyngeal jaws, which also have teeth. The moray uses the second set of jaws to help grab and swallow prey that might otherwise wriggle out of its mouth. The moray has a strong bite and doesn’t see very well, although its sense of smell is excellent. This occasionally causes problems for divers who think it would be fun to feed an eel and end up with a finger bitten off. Don’t feed the eels, okay? Not only that, but a moray can’t release its bite even if it’s dead, so if one bites a diver, someone has to pry the eel’s jaws open before the bite can be treated. And as if all that wasn’t warning enough to not feed wild animals, and frankly just stay out of the water entirely, research suggests that some morays are venomous. Oh, and the giant moray sometimes hunts with a fish called the roving coralgrouper, which grows to some four feet long, or 120 cm, which is a rare example of interspecies cooperative hunting.

Some people believe that at least some sightings of the Loch Ness monster can be attributed to eels—European eels, in this case. An eel can’t stick its head out of the water like Nessie is supposed to do, but it does sometimes swim on its side close to the water’s surface, which could result in sightings of a string of many humps undulating through the water. But while eels do live in and around Loch Ness, it’s unlikely that any European eel would grow much larger than around five feet, or 1.5 meters. Still, you never know. Loch Ness is the right habitat for an eel to grow to its maximum size, and while we have learned a lot about eels in general, and the European eel in particular, since Ollie was released into a well in Brantevik, we certainly don’t know everything about them.

One last note about eel larvae. Occasionally on facebook and other social media, well-meaning people will share warnings about a nearly invisible wormlike parasite that can be found in drinking water, with pictures of, you guessed it, eel larvae. Eel larvae are not parasites, are not found in fresh water at all, and even if you did accidentally swallow one, you’d just digest it and get a little protein out of the bargain. So you don’t need to worry about those clickbait warnings, the eels do.

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

Thanks for listening!

Episode 041: Comb Jellies and Sea Sponges THE CONTROVERSY

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We’re learning about comb jellies this week, along with the sea sponge, and the MASSIVE CONTROVERSY ABOUT THE TWO THAT IS PITTING SCIENTIST AGAINST SCIENTIST I might be overstating it just a bit

The lovely Arctic comb jelly:

The lovely Venus’s girdle comb jelly:

A fossil comb jelly. Probably lovely when it was alive:

A sea sponge (most are not this Muppet-like):

Show transcript:

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

For this week’s episode, we’re revisiting jellyfish, more properly known as jellies. The first jelly episode is far and away our most popular and I can’t figure out why. I mean, I’m glad people like it. This time, we’re going to learn all about comb jellies, which are not really as exciting as true jellies. There is no ship-sinkingly enormous comb jelly lurking in the oceans of the world. But they are really interesting.

When you think of a jelly, you probably picture a roughly bell-shaped thing with long stinging tentacles. But most comb jellies are more like egg-shaped blobs, and either don’t have tentacles at all or only have relatively small tentacles that don’t sting. Although they look alike superficially, comb jellies and true jellies are so different that scientists don’t think they’re very closely related at all. Comb jellies are officially called ctenophores (TEN-oh-fours), spelled with a c-t at the beginning if you were wondering. I looked up the pronunciation. Yeah, I know, I pronounced Pliny wrong all through episode 12, but come on, it looks like it should be pronounced Pliny and not Plinny. It’s not like anyone ever came up to me and said, “Hey, what about that Plinny, what a guy.” I just read the name.

But I digress, inexplicably.

Instead of pulsing its bell to maneuver in the water, a comb jelly has rows of tiny compact filaments called cilia, fused together in combs that help it swim. The combs are also called swimming plates.

There are two main types of comb jellies, those with tentacles and those without tentacles. The ones without are called Nuda, or Beroids, and while they don’t have tentacles, they do have combs of extra-large cilia, called macrocilia, that sever prey into pieces small enough to swallow. Mostly they eat other comb jellies. Beroids also have big mouths, but a beroid can actually seal its mouth shut while it’s moving so it’s more streamlined.

Comb jellies with tentacles are divided into eight orders roughly based on body shape. The most common order, the cydippida, are egg-shaped with a pair of thin tentacles that they use sort of like fishing lines. The tentacles are long and sticky, trapping tiny organisms or particles of food. Some species have branched tentacles but none have more than two. The tentacles can retract—when you see a picture of a comb jelly with a weird spring-like thing sticking out from its bottom, that’s a retracted tentacle, not anything gross like a poop. The tentacles contain cells called colloblasts. When an organism touches a tentacle, the colloblast cells rupture and basically release glue that keeps the prey from escaping.

A cydippid comb jelly also has eight combs that run from the top of the body to the bottom, which makes it look sort of like a fancy decorated egg. Comb jelly cilia are iridescent, by the way, so they reflect light in rainbow patterns. Basically what I’m saying is, these little guys are actually really pretty.

All comb jellies are predators, but most eat plankton and other tiny food, because most comb jellies are really small—only a few inches long at most. Bigger species may eat krill and small crustaceans. The biggest comb jelly, Cestum veneris, more often called Venus’s girdle, can grow some five feet long, or 1.5 meters, but only some two inches, or 5 cm, wide. It looks like a nearly transparent or purplish ribbon and lives in tropical and subtropical seas. I wouldn’t want to touch it, but it’s not exactly dangerous. In fact, it’s so delicate that a diver attempting to touch one may accidentally destroy it instead. A lot of comb jellies are that delicate, making them hard to study, so we still don’t know a whole lot about them.

Comb jellies only have one body opening, called a mouth for convenience sake although the jelly uses it for anything that requires a body opening. Until recently, researchers thought that included pooping. Yeah, now you see why it’s not exactly a mouth. But it turns out that a comb jelly has pores on the opposite end of its body from its mouth opening that it uses to release at least some particles of indigestible food. This is interesting since it helps scientists understand how the anus evolved.

There aren’t that many species of comb jellies, maybe 100 or so. But new ones are discovered occasionally, especially deep-sea comb jellies. While comb jellies that live near the surface of the ocean are usually transparent, many deep-sea species are red, since it’s a color most deep-sea animals can’t see. Most are also bioluminescent, and when threatened some species will secrete a luminescent goo. The predator may get confused and attack the goo while the comb jelly swims away as fast as its frantically waving cilia can take it.

If you’ve listened to episode 15, about the hammerhead shark and megalodon, you’ll remember that we don’t have a lot of shark fossils because shark skeletons are made of cartilage, not bone. We just have a lot of shark teeth, mostly. Now think about how big and solid sharks are, then think about how smooshy jellies are. Then try to imagine what a jelly fossil might look like. Yeah.

We do have some comb jelly fossils, though. But we don’t have many. Like, five. We have five. The oldest are from the mid-Cambrian, some 500 million years ago, but they were very different from the comb jellies living today. They had lots more combs, for one thing—between 24 and 80 instead of 8. Researchers have found other fossils that may be of comb jellies. There’s a good possibility that they were widespread throughout the oceans back then—but from genetic testing and other molecular analysis, it appears that the comb jellies alive today are all descended from a common ancestor that survived the Cretaceous-Paleogene extinction around 65 million years ago. So it’s possible that in addition to so many dinosaurs dying off, almost all comb jellies went extinct then too.

Just think, if that one species hadn’t survived and evolved into the comb jellies we have today, researchers might not have a clue what animal those comb jelly fossils represented. If you know about the Burgess shale fossils that have baffled and fascinated paleontologists for decades now, because so many of the fossils don’t resemble anything living today, then it’ll make sense to learn that a few of those five comb jelly fossils were actually found in the Burgess shale.

There are some other comb jelly fossils discovered in China and dated to 520 million years ago. But they don’t resemble the comb jellies living today at all because they had skeletons and spines. Pretty much every fossil found from the Cambrian had supportive or armored structures, even ones like comb jellies that don’t have those things today. I’ll probably do a whole episode eventually about the Cambrian period and the Burgess shale discoveries.

Anyway, there’s some controversy going on right now regarding whether comb jellies or sponges were the species that gave rise ultimately to all other animals, so let’s take a quick side trip and learn about sponges.

The sponge is a very simple animal, still around today. They don’t have any specialized structures like nerves or a digestive system or a circulatory system or organs. They’re just a sponge, basically. And if you were wondering, the sponge you use to clean your kitchen is named after the sea sponge, not vice versa, and you can still get actual dried sea sponges to use for cleaning. They’ve been used that way for millennia. It wasn’t until 1866 that scientists even realized sponges were animals and not plants.

Living sponges just hang out in the ocean or freshwater, stuck to a rock or something. Water flows through them and washes food and oxygen in and waste out. That’s it. That’s all a sponge does is let water flow through it. I feel like there’s a life lesson to be learned there, but I’m too busy doing ten things at once to figure it out.

Mostly sponges eat bacteria and other tiny food particles, although some eat small crustaceans and a few have developed a symbiotic relationship with plantlike microorganisms, which live safely in the sponge and produce enough food for both it and the sponge. Every so often a sponge will release eggs or sperm into the water. If the conditions around a sponge deteriorate, some species will create bundles of unspecialized cells called gemmules. When conditions improve, the gemmules will either grow into new sponges or, if the sponge that created them has died, it will recolonize the original sponge’s skeleton.

A sponge’s skeleton is a sponge, by the way. If you’ve got a natural sea sponge in your house, that’s what you’re cleaning your kitchen counters with, the skeleton of a sea sponge. Different sponges use different minerals to create their skeletons and most are pretty hard, but the ones sold as natural sponges are softer and throughout history have been used for everything from padding armor, applying paint, and filtering water. Loofah sponges aren’t actually made from sea sponges, though. They’re actually from the dried insides of the sponge gourd. I did not actually know that until just now.

Oh, and guess what else I just learned? There’s a small population of bottlenose dolphins in Western Australia that use sponges. The dolphins frequently hunt close to the bottom of the bay. To keep from scraping its rostrum, or bill, in the sand, a dolphin will sometimes stick a sponge under its chin. Researchers think that one especially smart dolphin figured this out and has been teaching her children how to do it ever since.

So that’s the sea sponge. Useful for many things, not much of a party animal. Compared to sea sponges, comb jellies are intellectual masterminds. Even though comb jellies don’t have brains.

Instead, comb jellies have a nerve net. The nerves are concentrated around its mouth and on its tentacles. It does also contain an organ that helps the jelly sense its orientation, basically so it knows which way is up. It usually swims with its mouth pointing upward, incidentally. But while the comb jelly’s nervous system is pretty sophisticated for such a simple animal, it’s also very different from other animals’ nervous systems. Like, super different. Its nerves are constructed from different molecules and use different neurotransmitters.

Its nerve cells are so different from other animals’ that some researchers think it actually evolved separately. Specifically, neuroscientist Leonid Moroz thinks so. He thinks that the first ancestor of comb jellies split off from the sea sponges some three quarters of a billion years ago and evolved separately from all other animals.

Since comb jellies use a different set of chemicals as other animals to accomplish the same tasks, a couple of articles I read make a big deal about how evolution must therefore follow a prescribed path—that animals must have certain traits to survive. But assuming comb jellies did split off from sponges that early and did evolve separately from other animals, they were still competing against those other animals. It’s not like they had an ocean to themselves, although that would be awesome if they did, because who knows what they might have evolved into?

The controversy about whether sea sponges or comb jellies were basically the trunk of the tree of animal life started in 2008, when a study in the journal Nature compared DNA sequences across a number of animal species and suggested that the comb jellies were evolutionarily first. A 2013 paper published in Science by another team of researchers made the same conclusion based on the genome of a species of comb jelly called the sea walnut. That is such a cute name. Don’t you just want to cuddle the little sea walnut and make little hats for it?

All this ignited what some articles call a firestorm of controversy. I like to imagine researchers reading the articles and FREAKING OUT. Moroz’s studies of the comb jelly’s nervous system, and the complete genome of a different comb jelly, the sea gooseberry, appeared in Nature in 2014. Moroz now thinks that nervous systems have developed independently at least nine times in various different groups.

The controversy at this point appears to have several factions. Moroz’s group thinks comb jellies split off from sponges, and that everything else split off from comb jellies but developed separately in the neurological sense. Another group thinks comb jellies split off from sponges and everything evolved from comb jellies, and that comb jellies aren’t all that weird neurologically. Another group thinks comb jellies and sponges split off from a common ancestor of both that had a simple nervous system, which comb jellies retained but sponges lost, and that everything else evolved from comb jellies. But then there’s the other side, the ones who think sure, comb jellies split off from sponges, but so did everything else ultimately, and comb jellies are no more the base of all animal life than the man in the moon.

One thing everyone agrees on, though, is that we still don’t know enough about comb jellies. And they are really pretty.

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

Thanks for listening!

Episode 037: The Dobhar-Chu

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This week we’re in Ireland learning about the dobhar-chú, a vicious creature that might be an otter but might be a KING otter! Either way, it’s a killer.

The weird creature carved on Grace Connolly’s gravestone:

How can such an adorable floof be so MURDEROUS? Eurasian otter:

The giant otter (from South America) imitating a sea serpent (hmm):

Giant otter has teeth:

Further reading:

The Search for the Last Undiscovered Animals by Karl PN Shuker

Show transcript:

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

We’re one week closer to Halloween, and it’s time to learn about a mysterious, deadly animal from Ireland called the Dobhar-chú (pronounced do-war-coo). Appropriately enough, our story starts in a graveyard.

Conwall Cemetery is in the town of Drummans, near the valley of Glenade. In the cemetery is a sandstone grave marker lying flat on the ground. It’s about 4 ½ feet wide and nearly two feet high, or 1.37 by .6 meters, and is dated September 24, 1722. The name on the stone is Grace Con, wife of Ter MacLoghlin. But the main part of the stone is made up of a carving of an animal.

I’ll put a picture of the carving in the show notes. It’s not very clear, but basically, it looks like a heavy-bodied dog with limbs folded beneath it as though it’s crouching. It has a long tail although that has mostly worn off. Its head is small, with tiny ears, and its neck is folded back so that its head lies along its back. A hand holds the hilt of a sword that is plunged into the animal’s neck, with the tip of the sword just visible below the belly.

There are various stories and poems about what happened to Grace Con, or Grace Connolly, but they’re all basically the same. Incidentally, it was Gaelic custom for women to retain their maiden names, which is why Grace’s last name doesn’t match her husband’s.

One morning Grace went down to the lake either to wash or to do laundry, reports differ. When she didn’t return home, her husband Terence McGloughlan went to find her. But when he reached the lake, he found his wife’s body–with a monstrous animal, the dobhar-chú, feeding on it. Terence killed the beast, but as it died it gave a piercing whistle or squeal. The squeal was answered by another animal from the lake, which surfaced and charged Terence.

He fled home just ahead of the monster, leaped on his horse, and galloped away with the monster pursuing. Eventually his horse tired, so Terence dismounted and turned the horse sideways across the road to act as a sort of shield. When the dobhar-chú ducked to run beneath the horse’s belly, Terence stabbed it through the heart.

Dobhar-chú is an Irish term meaning water-hound. It’s used as a name for the Eurasian otter, but can also refer to something called a master otter or king otter. But before we go any farther, let’s get some background on the otters that live in Ireland and Scotland, since the legend of the dobhar-chú is known in both places.

The Eurasian otter lives throughout Europe and Asia. It’s shy, solitary, and territorial. It’s a pretty big animal, and some big adult males can grow as long as four and a half feet, or 1.4 meters, including the tail. Females are smaller. The otter’s toes are webbed, which makes it a good swimmer. It’s dark brown above, grayish-brown below, with white or cream-colored markings around the throat and cheeks. It has a long, slender body and flattened head with tiny ears and sensitive whiskers. Oh, and it’s incredibly cute. Oh my gosh is it cute.

The otter eats fish, frogs, and invertebrates like crayfish. It lives in rivers and lakes and likes plenty of cover around the water’s edge. While it prefers fresh water, it will enter the ocean, but it needs fresh water both to drink and to clean salt from its coat. It’s usually nocturnal and is especially active at dusk and dawn, although if an otter’s territory is along the coast it will be more active during the day since it forages in rock pools at low tide for fish and invertebrates. Sometimes people call otters who live along the coast sea otters, but in Great Britain and most of Europe they’re the same type of otter that lives in freshwater.

Instead of having one den, an otter’s territory has a number of places where it sleeps or just hangs out. Above-ground areas are called couches and are well hidden in dense vegetation and frequently on small islands. Underground areas are called holts. A holt might be dug into a river bank, among a big tree’s roots, or just be a crevice among fallen rocks. A mother otter will have her babies in a holt that’s fairly remote from her usual activities. She usually has two or three babies at a time, called cubs.

An otter marks its territory with droppings that actually smell nice, like new-mown hay. I have not smelled them myself so I can’t vouch for this. The droppings are called spraints. While otters were once common throughout Europe, they’re much rarer these days, mostly because they can’t live in polluted streams, and these days they are totally protected. You’re not even allowed to damage an otter’s couch or holt, much less the otter itself.

Now we know about the otter, but what’s a master otter? According to Irish and Scottish folklore, it’s basically a super-otter. It’s much larger than a regular otter and sometimes appears with scores of regular otters as though leading them, and it may have some magic powers. Carrying its pelt, or part of its pelt, is said to protect someone from injury or shipwreck. One description says it’s white except for black ear tips and a black cross on its back, another says it’s half wolf, half fish. One account from 1684 calls it an Irish crocodile and describes it as “of the pitch of an ordinary greyhound, of a black slimy skin, without hair,” and says it’s also called a water-dog or Anchu. Whatever it is, it’s rare and dangerous.

So what might it be? As it happens, there is a species of otter that sounds a lot like the dobhar-chú. It’s called the giant otter, and while these days a big male is not much more than about 5 and a half feet long, or 1.7 meters, in the past before they were nearly driven extinct for their fur, big males sometimes grew eight feet long, or 2.4 meters. Those lengths don’t even include the tail. The giant otter is brown or reddish in color, but when it’s wet it looks black. It has a white pattern on its throat that individuals use to identify each other, because unlike other otters, the giant otter is social, communicates with its clan members with whistles and other noises, is mostly active during the day, and can be aggressive. All this sure sounds like the dobhar-chú. The only problem is, the giant otter lives in South America, an entire ocean away from Europe.

Could a similar species of giant otter have once lived in Ireland and Scotland? We don’t have very many otter fossils, unfortunately–but we do have a recently discovered fossil of a new otter species from China. It’s been named Siamogale melilutra and it’s twice the size of the giant otter. From its teeth, it probably ate a lot of freshwater shellfish. The fossil dates to 6.24 million years ago, so it’s not likely that it was running around in Ireland in the early 18th century. But it’s interesting to know that really big otters did once exist in Asia, so it’s always possible that a species of rare giant otter also lived in parts of Europe until fairly recently.

Of course, it might be that the dobhar-chú really is just a folktale and not based on a real animal at all. Some accounts of a king otter say it’s the seventh cub of an ordinary otter, and the king otter’s magical attributes also push it farther into the realm of folklore than objective reality. It’s also possible that the dobhar-chú and the king otter are completely different animals, one real, one a folktale, with some confusion between the two since that’s just how people think.

I’m inclined to think that might be the case. So if we assume that the dobhar-chú is just an unusually large otter, does it fit the reported story? Do otters ever attack people?

Otter attacks are extremely rare, and usually only occur if a mother otter feels someone is threatening her cubs. In North America, where the river otter is very similar to the Eurasian otter, only 44 documented cases of an otter attacking a human have been recorded since 1875. Then again, when an otter does attack it can actually kill a human. Heck, the North American river otter occasionally kills alligators. An otter’s bite is similar in strength to that of a big dog, and it will chase people for at least a short distance if provoked. It can run 18 mph, or 30 km per hour. Usain Bolt can sprint 28 mph, or 45 km per hour, but most of us are a lot slower no matter how motivated we are.

In August of 2016, a Quebec woman swimming in a lake was attacked by an otter that repeatedly bit her legs until she managed to reach a dock with a ladder. Fortunately the otter didn’t chase her once she left the water. Needless to say, this is extremely unusual behavior for an otter, but it does happen. In 2014 an eight-year-old boy and his grandmother were swimming in a river in Washington state when an otter attacked the boy. When his grandmother came to his rescue, the otter turned on her. In 2013 a woman swimming in Yellowstone National Park was bitten and clawed by an otter. Her face, arms, and hands were bitten and some bones in her right hand broken. Fortunately, all these people recovered fully, but all of them had to spend time in the hospital.

So if Grace Connolly was in the lake back in 1733, bathing or washing clothes, and an otter took exception to her presence, it might well have killed her. The rest of the story might be embellishment or the otter might have also chased or attacked Grace’s husband before he managed to kill it. Either way, I don’t think we need to hypothesize about a rare giant otter in this case. A regular otter in a bad mood is scary enough.

Those little guys are cute as all get out, but don’t get too close. They bite.

Next week we’ll take a look at another water monster, this one from the sea–a weird and hideous two-legged fish thing–as we get closer and closer to Halloween.

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

Thanks for listening!

Episode 034: Saber-Toothed Animals

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This week we’ve got a heaping helping of animals with big pointy teeth! Whether you spell it saber or sabre, you don’t want teeth of that description biting you.

Smilodon is the best saber-toothed cat:

Thylacosmilus’s weird chin bone:

Thylacosmilus might have looked something like this when alive:

Kolponomos might have looked something like this when alive:

And the sabertooth fish is still alive!

Show transcript:

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

For this week’s episode, we’re looking at saber-toothed animals. The animal people generally think of as THE saber-tooth cat, or saber-tooth tiger, is Smilodon fatalis. Smilodon and its relatives were members of the feline family, although not very closely related to the big and little cats living today. We have a whole bunch of Smilodon fossils, many from the La Brea tar pits in California.

Smilodon was probably descended from a saber-tooth cat called Megantereon, which lived in North America, Eurasia, and Africa. It might have still been around only half a million years ago, was definitely around as recently as 2.5 million years ago, definitely around as long as 4.5 million years ago, and recent finds have been tentatively dated to 7 million years ago. So Megantereon was a very successful animal. It was stocky with strong forelimbs and neck, with long upper canines—not as big as Smilodon’s, but certainly saber-toothed. It wasn’t a giant cat, probably close to a jaguar in size, with males probably being around 5 or 6 feet long (or around 1.5 meters) not including the tail and a little over 2 feet high at the shoulder, or 72 cm. It probably killed its prey by leaping on it and biting its throat.

Megantereon probably acted a lot like a leopard, including climbing trees, but its descendant, Smilodon, was too heavy for tree-climbing. Smilodon was a big, tough kitty about the size of a modern lion. It lived in North America, and migrated into South America at some point too. It probably looked more like a bear than a cat since it was stocky, heavily muscled, and had a broad head and jaws that could open much wider than modern cats’.

Smilodon cubs didn’t have saber teeth. A cub only started growing its big teeth when it was around a year and a half old, and by around three years old the fangs were fully grown, about 7” long or 18 cm. Very few remains of young Smilodons have been found in the La Brea tar pits, so researchers think cubs were mostly fed and cared for by their mother until they had fully grown fangs and had learned to use them.

For a long time researchers thought Smilodon lived in forested areas, but recent studies show that it probably preferred open areas. One 2016 study compared carbon and nitrogen isotopes found in collagen samples from bones of Smilodon and other predators with those of prey animals in South America to find out what they were eating. It turns out that Smilodon ate a lot of Megatherium and other giant ground sloths, as well as a camel-like ungulate called Macrauchenia. There’s even some evidence that Smilodon may have hunted in family groups. Overall, the finding suggests that Smilodon lived a lot more like modern lions do than like other big cats.

The first Smilodon fossils found date to around 2.5 million years ago, but remains found in Florida dated to 5 million years ago have recently been described as a related saber-toothed cat. Smilodon lived until only 10,000 years ago at the end of the Pleistocene. It preyed on ice age megafauna and researchers think it may have died out when its main prey animals went extinct. Humans probably had something to do with their extinction too.

Smilodon wasn’t the only big predator in North America during the ice age, though. It wasn’t even the only big feline predator. It shared its territory with the American lion and the American cheetah. Neither of those had saber teeth but they’re awesome so I’m going to tell you a little bit about them anyway.

The American lion died out at the same time as much of the other ice age megafauna, around 11,000 years ago. Unlike Smilodon, it’s closely related to modern big cats—in fact, most researchers consider it a subspecies of the modern African lion. We don’t know for sure if the males had manes, but we do know that the American lion was much bigger than modern lions although not as heavy as Smilodon. It probably stood almost four feet tall at the shoulder, or 1.2 meters. Remains of American lions have been found in the La Brea tar pits so we know they shared territory with Smilodon.

The American cheetah lived on the prairies of North America. Its body plan resembled the modern cheetah’s and it was built for speed, but researchers aren’t sure if it was actually closely related to the modern cheetah. It may be more closely related to the cougar. It was a little larger and heavier than a modern cheetah. Either way, it’s probably the reason why pronghorn antelopes are so fast. They can run over 55 miles per hour or 88 km per hour, much faster than gray wolves and cougars, their current predators. The American cheetah died out around 12,000 years ago.

There are a lot of saber-toothed cats known to science, all related to Smilodon. But there are other animals with similar teeth that are unrelated to the saber-toothed cats. Thylacosmilus atrox looked superficially like a saber-toothed cat. It lived in South America, with most fossils found in Argentina, and went extinct close to three million years ago, long before Smilodon appeared in South America. But Thylacosmilus wasn’t a feline at all. It wasn’t even slightly related to felines. In fact, it was a marsupial, sometimes called a pouched saber-tooth because marsupials keep their babies in pouches, like kangaroos and possums.

Thylacosmilus was about the same size as Megantereon or a modern jaguar. Its saber-like canines were bigger than Smilodon’s and had roots so deep they were practically pressed up against the braincase. But it had something no saber-toothed cat had. Its lower jaw had a pair of bony downward projections called flanges. Think of it as a chin that went horribly wrong. The chin bones pointed downward at the same angle that the fangs pointed downward, and apparently protected them. Researchers aren’t sure if the fangs were actually inside the mouth or just pressed up against the outside of the chin.

Like Smilodon and its relatives, Thylacosmilus had immensely powerful forelegs that it used to grapple prey. But its jaws were weak. Smilodon’s jaws were much weaker than a big cat’s, but Thylacosmilus literally couldn’t outbite a domestic cat. Researchers think it grappled and subdued its prey with its forelegs, then delivered a precision bite with its fangs that severed the animal’s windpipe or major neck arteries. To do this, it didn’t need a strong bite, it needed strong neck muscles, and that’s exactly what it had.

Kolponomos was another saber-toothed animal, totally unlike Smilodon except for its teeth and powerful neck muscles. It’s related to bears, but that branch of the bear family also gave rise to pinnipeds like seals. Kolponomos lived around 20 million years ago along the Pacific coast and used its fangs not to bite the necks of its prey, but to pry shellfish off of rocks. Its snout was narrow and sloped downward, but we don’t have a complete skeleton so we don’t know how big it was or what it really looked like, but it probably resembled a buff sea otter with big fangs more than a seal or bear.

Clearly, saber teeth have evolved multiple times in different types of animals to serve different purposes. They’re not a recent development, either. 250 million years ago, just before dinosaurs evolved and took over the world. An animal called a gorgonopsid, or gorgon for short, lived in what is now Africa and Eurasia. Not a whole lot was known about it until 1998 when a very nearly complete skeleton was discovered in South Africa.

Complete skeletons are almost never found in the fossil record. Dinosaur and other animal skeletons displayed in museums are usually assembled from different individual animals. Sometimes a particular bone has never been found at all so scientists have to make an educated guess. But this gorgon looked like it had died and just flopped over. Nothing ate parts of it, nothing scattered its bones after it decayed. There it was, just waiting for the paleo team to find it.

Gorgon wasn’t a mammal. It wasn’t exactly a reptile either. It was a precursor to mammals, a reptilian creature with mammalian characteristics. It resembled a lion crossed with a monitor lizard, although researchers aren’t sure if it had actual fur or both bristles and scales. It was big—some ten feet or 3 meters long with saber-tooth fangs nearly 5” or 12 centimeters long. Reptiles living today have legs that stick out from the sides of their bodies, so when they walk their bellies are very close to the ground, but gorgon’s stance was different. Its walk probably resembled what’s called the “high walk” of crocodilians, where the gator lifts its body and tail off the ground entirely to walk more easily and quickly on land. Researchers think gorgon hunted by ambushing its prey and delivering a massive bite, then retreating to wait for the injured animal to weaken. This is similar to how komodo dragons hunt.

Gorgon died off in the Permo-Triassic extinction event 250 million years ago. Everyone knows about the Cretaceous-Paleogene extinction that ended the rule of the dinosaurs, but the Permo-Triassic extinction was even worse. More than 95% of all marine animals died out, and some 70% of land animals. Even a lot of insects went extinct, and some evidence suggests that a lot of plants went extinct too. Scientists don’t know what caused the extinctions, but it might have been a meteor strike like the one generally accepted to have caused the Cretaceous-Paleogene event. Whatever happened, it hit marine life hard because the oceans became extremely acidic due to increased CO2 levels in the air and the increased temperature at the ocean’s surface in many areas—104o F or 40o C. It took millions of years for the oceans to recover.

So far all the animals in this episode are extinct. While a lot of living animals have fangs of one kind or another, there don’t seem to be any that use their fangs the way saber-toothed cats did. But I don’t want to leave you after saying, “Yeah, something happened and everything DIED,” so I’ll finish up by talking about the sabertooth fish, of the family Evermannellidae. It’s alive and it’s wonderfully creepy.

The sabertooth fish lives in the depths of tropical and subtropical waters. It has tubular eyes that point upwards so it can see its prey, mostly squid, silhouetted against the far-off surface. It’s grayish-brown in color with a greenish iridescence. Its fins are brown. It has smooth skin without scales and a big mouth that can open extremely wide, which is good because the sabertooth fish can swallow prey that’s actually bigger than it is. Its stomach distends to hold whatever can fit down its gullet. This sounds terrifying, especially when you look at its teeth, but keep in mind that it’s only about seven inches long, or 18 cm. It has two pairs of curved fangs, one in the upper jaw, one in the lower, with smaller teeth in the back of its mouth. If you’ve ever tried to catch a living squid with just your mouth—and I really hope you have not—you’ll probably have noticed that it’s hard to keep the squid from slithering away. Wouldn’t some saber teeth help with that? The sabertooth fish thinks so.

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

Thanks for listening!

 

Episode 033: Dunkleosteus, Helicoprion, and their weird-toothed friends

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This week we’ll learn about some terrifying extinct fish, the armored dunkleosteus and the spiral-toothed helicoprion, plus a few friends of theirs who could TEAR YOU UP.

Dunkleosteus did not even need teeth:

Helicoprion had teeth like crazy in a buzzsaw-like tooth whorl:

Helicoprion’s living relatives, chimaeras (or ghost sharks) are a lot less impressive than they sound:

Helicoprion probably looked something like this:

But helicoprion has been described in all sorts of wacky ways over the years:

So what are the odds this rendition of edestus is correct? hmm

Show transcript:

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

This week we’ve got a listener suggestion! Will B. suggested placoderms, which were armored fish that lived hundreds of millions of years ago. He especially recommended Dunkleosteus. I looked it up and went, “Oh holy crap,” so you bet we’re going to learn about it today. I’m also pairing that terrifying fish with a really weird shark relation called Helicoprion. And we might even take a look at a few other fishes while we’re at it. Creepy extinct fish for everyone! Oh, and Will asked that I include more metric conversions. [heavy sigh] okay I guess

If you had happened to live around 350 million years ago when Dunkleosteus was alive, you would be a fish. Well, you would probably be a fish. I don’t know for sure. That was during the Late Devonian period, and the Devonian is remembered as the “age of fish” by undergraduate geology and palaeo students everywhere. While land plants were evolving like crazy, developing true roots and seeds, fish were even crazier. Ray-finned fish evolved during the Devonian and so did lobe-finned fish like coelacanths. The first amphibious critters developed in shallow lakes and started to spend time on land, and in the ocean there were early sharks, lots of trilobites, and a whole lot of armored fish. Including, eventually, dunkleosteus.

Dunkleosteus terrelli was the biggest species of placoderm. It probably grew over 30 feet long OR TEN METERS, WILL, which made it bigger than a great white shark. But dunkleosteus didn’t have teeth. And before you think, oh, it must have been a filter feeder or something, oh no. It didn’t need teeth. Instead it had bony plates like a gigantic beak. It could open and close its jaws incredibly fast—something like one 50th of a second—and could bite through armor and bone no problem. One article referred to its jaws as sheet-metal cutters. Scientists think its bite was as powerful as that of a T rex, although it didn’t quite match that of megalodon, but since T rex and megalodon both lived many millions of years later than Dunkleosteus, it’s useless to speculate who would win in a fight. But my money’s on Dunkleosteus.

Dunkleosteus wasn’t a fast swimmer. Its head was covered in heavy armor that probably served two main purposes. One, the armor plates gave its massive jaw muscles something substantial to attach to, and two, it kept its head safe from the bites of other placoderms. That’s right. Dunkleosteus was a cannibal.

We actually don’t know exactly how long Dunkleosteus was or what most of its body looked like. The only fossils we’ve found were of the head armor. We do have complete fossils and body impressions of other, much smaller placoderms, so since all placoderms seemed to have the same body plan we can make good guesses as to what Dunkleosteus looked like.

One surprising thing we do have associated with Dunkleosteus fossils are some remains of its meals. These are called fish boluses, and they’re basically just wads of partially-digested pieces of fish that either get horked up by whatever ate them or pass through the digestive tract without being fully digested. From the fish boluses, we know that Dunkleosteus probably preferred the soft parts of its prey and didn’t digest bones very well.

In 2013, a fossil fish over 400 million years old was described that combines features of a placoderm skeleton with the jaw structure that most bony fishes and four-footed animals share. Some other early bony fishes discovered recently also show some features of placoderm skeletons. What does that mean? Well, until these discoveries, researchers had thought bony fishes weren’t very closely related to placoderms. Now it looks like they were. And that means that placoderm jaws, those fearsome cutting machines, were actually the basis of our own jaws and those of most animals alive today. Only, in our case they’re no longer designed to shear through armor and bone. Maybe through Nutter Butters and ham sandwiches instead.

So what happened to dunkleosteus? Around 375 million years ago something happened in the oceans—not precisely an extinction event, but from our perspective it looks like one. Even without human help species do go extinct naturally every so often, and when that happens other species evolve to fill their ecological niches. But during the late Devonian, when species went extinct in the ocean… nothing took their place.

We don’t know what exactly was going on, but researchers have theories. One suggestion is that, since sea levels were rising, marine environments that were once separated by land got joined together. Species that had evolved in one area suddenly had access to a much bigger area. They acted like invasive species do today, driving native species to extinction and breeding prolifically. They kept new species from developing, and caused a breakdown in the biodiversity of their new territories. This only happened in the oceans, not on land, which adds credence to the theory.

It took a long, long time for the oceans to fully recover. For example, coral reefs disappeared from the fossil record for 100 million years as corals almost died out completely. But the animals that had already started evolving to take advantage of life on land survived and thrived—and that led to us, eventually. Us and our little unarmored jaws.

From Dunkleosteus and its sheet-metal cutter beak let’s go to another fish that looked like a shark but had teeth that are so bizarre I can’t even understand it. Helicoprion and its tooth whorl have baffled scientists for over a century.

The various species of Helicoprion lived around 290 million years ago. Like sharks, only its teeth are bony. The rest of its skeleton is made of cartilage, which doesn’t preserve very well.

So what’s a tooth whorl? It resembles a spiral shell, like a snail’s, only made of teeth. I’m not even making this up. Originally people actually thought they were some kind of weird spiky ammonite shell, in fact. Then someone pointed out that they were made of teeth, but no one could figure out what earthly use a circular saw would be if you were a fish and just wanted to eat other fish. Where would you even keep a circular saw of teeth?

Various suggestions included putting the tooth whorl at the very end of the lower jaw, just sort of stuck out there doing nothing; putting the tooth whorl way in the back of the throat where I guess it would cut up fish as they went down; on the snout, on the back, or even on the tail, which are not places where teeth typically do much good. Originally researchers thought the tooth whorl was probably a defensive trait, but now it’s accepted that it was used the way the rest of us use our teeth, which is to eat things with.

The smallest teeth in a tooth whorl are on the inside curls and the biggest are on the outside. Eventually researchers realized the small teeth were from when the individual was a baby fish and had little teeth. Like sharks, helicoprion kept growing teeth throughout its life. Unlike sharks, it didn’t lose its old teeth when the new ones grew in. The older, smaller teeth were just pushed forward along the curve of the whorl and eventually were buried within the animal’s jaw, with only the biggest, newest teeth actually being used.

In 1950 a crushed tooth whorl was found with some cranial cartilage, so scientists knew that the whorl was associated with the head and wasn’t, for instance, on the dorsal fin. That fossil was found in Idaho and consisted of 117 teeth. The whorl was 23 cm in diameter, or about 9 inches across, although slightly larger ones have been found. In 2011 the fossil was examined with a state-of-the-art CT scanner and a 3D computer model generated of the animal’s skull.

Researchers think they have a pretty good idea of what a living helicoprion’s head and jaws looked like. The tooth whorl was fused with and extended the full length of the lower jaw. It grew inside the mouth roughly where the tongue would be if it had a tongue, which it did not. Helicoprion didn’t have teeth in its upper jaw, so the tooth whorl acted less like chompers than like a meat slicing machine. When it closed its mouth, the tooth whorl was pushed back a little and would therefore slice through any soft-bodied prey in the mouth and also force its prey deeper into its mouth. Helicoprion probably ate small fish, cephalopods, and other soft-bodied organisms.

Since we don’t have any fossils or impressions of helicoprion’s body, we don’t know for sure what it looked like, but researchers estimate it probably grew to around 13 feet or 4 meters, but may have possibly exceeded 24 feet or 7.5 meters.

For a long time researchers thought helicoprion was a shark, but it’s now classified as a type of chimaera, which are small weird-looking shark-like fish known also as ghost sharks, spookfish, ratfish, and rabbit fish. I’m going to call them ghost sharks because that’s awesome. They’re not that closely related to sharks although they do have cartilaginous skeletons, and most species like the ocean depths. Ghost sharks have been spotted at depths of 8,500 feet, or 2,600 meters. The longest any species grows is around 5 feet, or 150 cm. Unlike helicoprion, they don’t have exciting teeth. They don’t really have teeth at all, just three pairs of tooth plates that grind together. Some species have a venomous spine in front of the dorsal fin.

While we’re talking about shark-like fish with weird teeth, let’s discuss Edestus, a genus of shark-like fish with weird teeth that lived around 300 million years ago, around the same time as dunkleosteus. It was related to helicoprion but it didn’t have a tooth whorl. Instead it had one curved bracket of teeth on the lower jaw and one on the upper jaw that meshed together like pinking shears. You know what pinking shears are even if you don’t recognize the name. Pinking shears are scissors that have a zigzag pattern instead of a straight edge, so you can cut a zigzag into cloth but not paper because do not dare use my pinking shears for anything but cloth. It dulls them.

Anyway, like helicoprion Edestus didn’t shed its teeth but it did grow new ones throughout its life, so like helicoprion it had a bunch of teeth it no longer needed. In Edestus’s case we don’t have any bits of skull or jaw cartilage to give us a clue as to how its teeth sat in its jaw. A lot of scientific art of Edestus shows a shark with a pointy mouth, where the upper point curves upward and the lower point curves downward with teeth sticking out from the middle. Sort of like an open zipper, if the zipper part was teeth and the non-zipper side was a shark’s mouth. To me that looks sort of ridiculous, and I suspect in reality Edestus looked a lot more like helicoprion. The downward and upward curved parts of the tooth arc was probably buried within its jaw, not sticking out. But that’s just a guess based on about 30 minutes of research.

Researchers estimate that the largest species of Edestus probably grew to about 20 feet long, or 6 meters. No one’s sure how or what it ate, but one suggestion is that if its teeth did project out of its mouth, it might have slashed at prey with its teeth sort of like a swordfish slashes prey with its elongated beak. Hopefully scientists will find a well preserved specimen one day that will give us some clues as to what Edestus looked like, at which point I bet the drawings we have now will look as silly as helicoprion with a tooth whorl perched on its nose.

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