Monthly Archives: June 2019

Episode 125: Triceratops and other ceratopsids

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It’s time to learn about some more dinosaurs, ceratopsids, including the well-known Triceratops!

Triceratops:

An artist’s frankly awesome rendition of Sinoceratops. I love it:

A Kosmoceratops skull:

Pachyrhinosaurus had a massive snoot:

Protoceratops:

Fighting dinos!

Show transcript:

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

Back in episode 107, about ankylosaurus and stegosaurus, I mentioned that one day I’d do an episode all about triceratops and its relations. Well, that day is today. It’s the ceratopsid episode!

Ceratopsids are a family of dinosaurs with elaborate horns on their faces and frills on the back of their heads. They almost all lived in what is now North America and most of them lived in the late Cretaceous. Triceratops is the most well known, so we’ll start with it.

The name triceratops, of course, means three face horns, and it did indeed have three face horns. It had one on its nose and two on its brow, plus a frill that projected from the back of its skull.

Triceratops was a big animal, around 10 feet high at the shoulder, or 3 meters, and about 30 feet long, or 9 meters. Its body was bulky and heavy, sort of like a rhinoceros but, you know, even bigger and more terrifying.

Like the rhinoceros, triceratops was a herbivore. It had a horny beak something like a turtle’s that it probably used to grab plant material, and it had some 40 teeth on each side of the jaw. These teeth were replaced every so often as the old ones wore down, sort of like crocodilians do. Back when triceratops lived, around 68 million years ago, grass hadn’t developed yet. There were prairies in parts of western North America the same way there are today, but instead of grass, the prairies were covered in ferns. Many researchers think triceratops mostly ate ferns, grazing on them the same way bison graze on grass today.

In fact, the first paleontologist to study a triceratops fossil thought it was an extinct type of bison. This was a man called Othniel Charles Marsh. To his credit, Marsh only had a little piece of a triceratops skull to examine, the piece with the brow horns. And since the brow horns of a triceratops do look a little like the horn cores of a bovid, and since this was 1887 before a lot was known about dinosaurs, and since the fossil was found in Colorado where the buffalo roam, it’s understandable that Marsh would have assumed he was looking at a gigantic fossil bison skull. He figured it out the following year after examining another skull with the nose horn intact, since bovids are not known for their nose horns, and he naturally named it Triceratops.

It’s tempting to assume that Triceratops was a herd animal, but we don’t have any evidence that it lived in groups. It was common and we have lots of fossil triceratops, especially the thick-boned skulls, but it seems to have mostly been a solitary animal.

It’s pretty obvious that the triceratops’ horns must have been for defense. It lived at the same time as Tyrannosaurus rex, which preyed on triceratops often enough that we have a lot of Triceratops fossils with T rex tooth marks in the bones. We also have some triceratops fossils with T rex tooth marks in the bones that show signs of healing, indicating that the triceratops successfully fended off the T rex and lived. But what was the frill for?

Researchers have been trying to figure this out for years. There were a lot of different ceratopsid species, many of which may have overlapped in range and lived at the same time, so some researchers suggest the frill’s size and shape may have helped individuals find mates of the same species. Triceratops has a rather plain frill compared to many ceratopsid species, which had frills decorated with points, spikes, scalloped edges, lobes, and other ornaments.

But the ornamental elements of the frills change rapidly through the generations, which suggests that they weren’t for species recognition. If that was the case, the frills would have stayed about the same to minimize confusion. Instead, they get more and more elaborate, which suggests that they were a way to attract mates who liked fancy head frills. You know, like a snazzy hairstyle.

Of course, the frill could have more than one use. It could be attractive to potential mates and also could have protected the back of the skull from T rex bites, just like a snazzy hairstyle still keeps your head warm in cold weather. Then again, in many species of ceratopsid the frill is thin and rather fragile, so it’s more likely to be just for display. It’s very likely that the frills were brightly colored or patterned.

So what were some of these other ceratopsids with strange shaped frills? I’m SO glad you asked! There were so many ceratopsids, and they all had bodies shaped roughly the same but with head frills and horns that looked very different from each other. Some had no horns, just a frill. Some just had a nose horn, some just had brow horns. The horns were shaped differently in different species, too. Researchers group ceratopsids into two major groups: the chasmosaurines, which have longer frills and usually long brow horns and short nose horns; and the centrosaurines, which typically had larger nose horns and small brow horns, and snouts that were thicker top to bottom.

Almost all the ceratopsids have been found in North America, where they were super common in the Cretaceous. But Sinoceratops was discovered in 2008 in China. It wasn’t as big as Triceratops, topping out at about 6 ½ feet tall, or 2 meters, but what it lacked in bulk it made up in head frill ornamentation. Its frill was relatively short and was edged with small horns that curve forward. Its frill also had knobs along its edge and down the middle, which is unique among all ceratopsids and may have been the base for small keratin horns. Since keratin doesn’t fossilize, we have no way of knowing. It also had two holes in the frill that made it lighter, but they would have been covered with skin (no matter what a certain movie may have led you to believe). Its single nose horn pointed almost straight up, and in front of the nose horn it had a bony knob. It basically had no brow horns, just what may have been bony knobs above its eyes.

Kosmoceratops had probably the most ornamented skull of any known ceratopsid, and maybe any known dinosaur, with 15 horns growing from it. The rear of its frill curled forward like a collar, edged with flat, pointed projections. The frill was scalloped along its sides. Its brow horns were long, pointy, and arched sideways and slightly downward. Kosmoceratops also had a cheek horn under each eye and a flattened nose horn just in front of the brow horns. It lived in what is now Utah, in the United States, some 76 million years ago, and was only described in 2010.

Pachyrhinosaurus had flattened bony nose and brow horns more properly called bosses, since they aren’t actually horns. But Pachyrhinosaurus did have horns on its frill, although the size, shape, and number of the frill horns vary from individual to individual.

These bosses resemble the base of rhinoceros horns, which as you may recall are made of keratin. Some researchers think the bosses found in Pachyrhinosaurus and other ceratopsids may have also had keratin horns growing from them.

Remember how I said Triceratops didn’t appear to be a herd animal? Triceratops is considered a chasmosaurine, and chasmosaurines all seemed to be fairly solitary animals. But the other big group of ceratopsids, centrosaurines, may have been herd animals. Pachyrhinosaurus was a centrosaurine, for instance, and several bonebeds containing dense collections of fossil pachyrhinosaurus have been found where the individuals appear to have died at the same time. The biggest found so far is in Alberta, Canada, where paleontologists have excavated thousands of bones, from full grown adults to babies. Researchers suggest a herd of the animals may have died trying to cross a flooded river. The species of Pachyrhinosaurus found in the Alberta bonebed had both bosses and short brow horns.

Even though only one species of ceratopsid has been discovered in Asia so far, earlier basal forms were common in Asia. Protoceratops, which only stood about two feet tall, or 60 cm, lived in what is now the Gobi Desert in Mongolia around 80 million years ago. Researchers think some of these early species in the genus Protoceratops migrated into North America on the Bering land bridge, where they evolved into ceratopsids.

Protoceratops looked like a mini ceratopsid with a simple neck frill and no horns. We have a lot of Protoceratops fossils and some of them are frankly amazing.

For instance, a Protoceratops fossil found in 1965 was preserved with its own footprint in the ground near it. The fossils of baby protoceratopses have been found together in one nest, which suggests the parents cared for their young. We even have a fossil of a protoceratops and a Velociraptor that both died together while fighting. The velociraptor’s hind leg is extended where it kicked protoceratops with its vicious claws, but the velociraptor’s arm is in protoceratops’s jaws, broken.

Fighting dinosaurs. It’s one of those things that makes life worth living, you know?

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 124: Updates 2 and a new human

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It’s our second updates and corrections episode! Thanks to everyone who sent in corrections and suggestions for this one! It’s not as comprehensive as I’d have liked, but there’s lots of interesting stuff in here. Stick around to the end to learn about a new species of human recently discovered on the island of Luzon.

The triple-hybrid warbler:

Further reading:

New species of ancient human discovered in the Philippines: Homo luzonensis

Show transcript:

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

Yes, it’s our second updates episode, but don’t worry, it won’t be boring!

First, a few corrections. In episode 45 I talked about monotreme, marsupial, and placental mammals, and Tara points out that the placenta and bag of waters are different things. I got them mixed up in the episode. The bag of waters is also called the amniotic sac, which protects and cushions the growing baby inside with special amniotic fluid. The placenta is an organ attached to the lining of the womb, with the bag of waters inside the placenta. The umbilical cord connects the baby to the placenta, which supplies it with all its needs, including oxygen since obviously it can’t breathe yet.

Next, I covered this correction in in episode 111 too, but Judith points out that the picture I had in episode 93 of the Queen Alexandra’s birdwing butterfly was actually of an atlas moth. I’ve corrected the picture and if you want to learn more about the atlas moth, you can listen to episode 111.

Next, Pranav pointed out that in the last updates episode I said that the only bears from Africa went extinct around 3 million years ago–but the Atlas bear survived in Africa until the late 19th century. The Atlas bear was a subspecies of brown bear that lived in the Atlas Mountains in northern Africa, and I totally can’t believe I missed that when I was researching the nandi bear last year!

Finally, ever since episode 66 people have been emailing me about Tyrannosaurus rex, specifically my claim that it was the biggest land carnivore ever. I don’t remember where I found that information but it may or may not be the case, depending on how you’re defining biggest. Biggest could mean heaviest, tallest, longest, or some combination of features pertaining to size.

Then again, in 1991 a T rex was discovered in Canada, but it was so big and heavy and in such hard stone that it took decades to excavate and prepare so that it can be studied. And it turns out to be the biggest T rex ever found. It’s also a remarkably complete fossil, with over 70% of its skeleton remaining.

The T rex is nicknamed Scotty and was discovered in Saskatchewan. It lived about 68 million years ago, and turns out to not only be the biggest T rex found so far, it was probably the oldest. Paleontologists estimate it was over 30 years old when it died. It was 43 feet long, or 13 meters. This makes it bigger than the previously largest T rex found, Sue, who was 40 feet long, or 12.3 meters. Scotty also appears to be the heaviest of all the T rexes found, although estimates of its weight vary a lot. Of course some researchers debate Scotty’s size, since obviously it’s impossible to really know how big or heavy a living dinosaur was by just looking at its fossils. But Scotty was definitely at least a little bigger than Sue.

Scotty is on display at the Royal Saskatchewan Museum in Canada.

Way back in episode 12, I talked about snakes that were supposed to make noises of one kind or another. Many snakes do make sounds, but overall they’re usually very quiet animals. A snake called the bushmaster viper that lives in parts of Central America has long been rumored to sing like a bird. The bushmaster can grow up to ten feet long, or 3 meters, and its venom can be deadly to humans.

Recently, researchers discovered the source of the bushmaster’s supposed song. It’s not a snake singing. It’s not a bird singing. It’s not even a single animal–it’s two, both of them tree frogs. One of the frogs is new to science, the other is a little-known frog related to the new one.

I tried so hard to find audio of this frog, and I’m very bitter to report that I had no luck. The closest I could find was not great audio of this frog, whose name I forgot to write down, which I think is related to the new frogs.

[frog sound]

Now let’s do some quick, short updates, mostly from recent articles I’ve happened across while researching other things.

A triple-hybrid warbler, its mother a golden-winged/blue-winged hybrid (also called a Brewster’s warbler) and its father a warbler from a different genus, chestnut-sided, was sighted in May of 2018 by a birder in Pennsylvania. Lowell Burket noticed it had characteristics of both a blue-winged and a golden-winged warbler but sang like a chestnut-sided warbler. He contacted the Cornell Evolutionary Biology Lab about the bird with photos and video of it, and they sent a researcher, David Toews, out to look at it. Toews caught the bird, measured it, and took a blood sample for analysis. I think a listener told me about this article but I didn’t write down who, so thank you, mystery person.

Red-fronted lemurs chew on certain types of millipedes and rub the chewed-up millipedes on their tails and their butts. They also eat some of the millipedes. Researchers think the millipedes secrete a substance called benzoquinone, which acts as an insect repellant and may also help the lemurs get rid of intestinal parasites. Other animals rub crushed millipedes on their bodies for the same reasons.

A recent study of saber-toothed cat fossils show that many of the animals with injuries to their jaws and teeth that would have kept them from hunting properly survived on softer foods like meat and fat. Researchers think the injured cats were provided with food by other cats, which suggests they were social animals. The study examined micro-abrasions on the cats’ teeth that give researchers clues about what kinds of food the animals ate.

Simon sent me an article about a 228 million year old fossil turtle, Eorhynchochelys [ay-oh-rink-ah-keel-us]. It was definitely a turtle but it didn’t have a shell. Instead, its ribs were wide, which gave its body a turtle-like shape. Turtle shells actually evolved from widened ribs like these. Researchers are especially interested because Eorhynchochelys had a beak like modern turtles, while the other ancient turtle we know of had a partial shell but no beak. This gives researchers a better idea of how turtles evolved. Oh, and in case you were wondering, Eorhynchochelys grew over six feet long, or over 1.8 meters.

The elephant bird, featured in episode 51, was a giant flightless bird that lived in Madagascar. Recently new research about elephant birds has revealed some interesting information. For one thing, we now know what the biggest bird that ever lived was. It’s called Vorombe titan and grew nearly ten feet tall, or 3 meters, and weighed up to 1,800 lbs, or 800 kg. It was first discovered in 1894 but not recognized as its own species until 2018.

There’s also some evidence that at least some elephant bird species may have been nocturnal with extremely poor vision. This is the case with the kiwi bird, which is related to the elephant bird. Brain reconstruction studies of two species of elephant bird reveal that the part of its brain that processed vision was very small. It resembles the kiwi’s brain, in fact. One of the species studied had a larger area of the brain that processed smell, which researchers hypothesize may mean it lived in forested areas.

Another study of the elephant bird bones show evidence that the birds were killed and eaten by humans. But the bones date to more than 10,000 years ago. Humans supposedly didn’t live in Madagascar until 4,000 years ago at the earliest. So not only is there now evidence that people colonized the island 6,000 years earlier than previously thought, researchers now want to find out why elephant birds and humans coexisted on the island for some 9,000 years before the elephant bird went extinct. Hopefully archaeologists can uncover more information about the earliest people to arrive on Madagascar, which may help us learn more about how they interacted with the elephant bird and other extinct animals of the island.

Speaking of humans, humans evolved in Africa and until very recently, evolutionarily speaking, that’s where we all lived. Scientists rely on fossils, archaeological materials, and studies of ancient DNA to determine when and where humans spread beyond Africa. But at the moment, the DNA that researchers have studied doesn’t overlap entirely with what we’ve learned from the other sources. Basically this means that there are big chunks of data we still need to find to get a better picture of where our ancestors traveled. Part of the problem is that DNA preserves best in cold, dry areas, so most of the viable DNA recovered is from middle Eurasia. Fortunately, DNA technology is becoming more and more refined every year.

This brings us to a suggestion by Nicholas, who told me about a newly discovered hominin called Homo luzonensis. Homo luzonensis lived on an island called Luzon in the Philippines at least 50,000 years ago. It wasn’t a direct ancestor to Homo sapiens but was one of our cousins, although we don’t know yet how closely related.

No one thought humans could reach the island of Luzon until relatively recent times, because of how remote it is and because it hadn’t been connected to the mainland for the last 2 ½ million years. But when Homo floresiensis was discovered in 2004 on the island of Flores in Indonesia, which you may remember from episode 26, suddenly scientists got interested in other islands. Researchers knew there had been human settlements on Luzon 25,000 years ago, but no one had bothered to search for older settlements. In 2007 a team of paleoanthropologists returned to the island and found a foot bone that looked human. In 2011 and 2015 the team found some teeth and more bones from at least three different individuals.

We don’t know a whole lot about the Luzon humans yet. The discoveries are still too new. The Luzon hominins have a combination of features that are unique, a mixture of traits that appear more modern and traits that are seen in more ancient hominins. They’re also smaller in stature than modern humans, closer to the size of the Flores people. Homo luzonensis apparently used stone tools since researchers have found animal bones that show cut marks from butchering.

Researchers are starting to put together a picture of South Asia in ancient times, 50,000 years ago and more, and it’s becoming clear that there were a surprising number of hominins in the area. It’s also becoming clear that hominins lived in the area a lot longer ago than we thought. Researchers have found stone tools on the island of Sulawesi that date back at least 118,000 years. Even on Luzon, in 2018 researchers found stone tools and rhinoceros bones with butcher marks that date back over 700,000 years ago. We don’t know who those people were or if they were the ancestors of the Luzon people. We just know that they liked to eat rhino meat, which is one data point.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 123: Linnaeus’s mystery animals

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Carolus Linnaeus was a botanist who worked out modern taxonomy and binomial nomenclature, but there are two mystery animals associated with his work. Let’s find out about them!

Rembrandt sketched this elephant whose skeleton is now the type specimen of the Asian elephant:

Linnaeus’s original entry about Furia infernalis:

Further reading:

Ewen Callaway, “Linnaeus’s Asian elephant was wrong species”

Karl Shuker, “Linnaeus’s Hellish Fury Worm – The History (and Mystery) of a Non-Existent Micro-Assassin”

Show transcript:

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

This week let’s learn a little something about binomial nomenclature, which is the system for giving organisms scientific names. Then we’ll learn about a couple of mystery animals associated with the guy who invented binomial nomenclature.

That guy was Carlolus Linnaeus, a Swedish botanist who lived in the 18th century. Botany is the study of plants. If you’ve ever tried to figure out what a particular plant is called, you can understand how frustrating it must have been for botanists back then. The same plant can have dozens of common names depending on who you ask.

When I was a kid, the local name for a common plant with edible leaves that tasted deliciously tart was rabbit grass. I’ve never heard anyone anywhere else call it rabbit grass. Maybe you know it as sourgrass or false shamrock or wood sorrel.

There are over a hundred species of that plant throughout the world in the genus Oxalis, so it’s also sometimes just called oxalis. The species that’s most common in East Tennessee where I grew up is Oxalis dellenii, but all species look pretty much the same unless you get down on your stomach and really study the leaves and the flower petals and the stems. So if you were a botanist wanting to talk to another botanist about Oxalis dellenii back in the early 18th century, you couldn’t call it Oxalis dellennii. Not yet. You’d have to say, hey, do you know what rabbit grass is? And the other botanist would say, why no, I have never heard of this no doubt rare and astounding plant; and you’d produce a pot full of this pretty little weed that will grow just about anywhere, and the other botanist would look at it and say, “Oh. You mean sourgrass.” But imagine if you weren’t right by the other botanist and didn’t have the plant to show them. You’d have to draw it and label the drawing and write a paragraph describing it, just so the other botanist would have a clue about which plant you were discussing. Nowadays, all you have to do is say, “Hey, are you familiar with Oxalis dellenii?” and the other botanist will say, “Ah yes, although I myself believe it is the same as Oxalis stricta and that the differences some botanists insist on are not significant.” And then you’d fight. But at least you’d know what plant you were both fighting about.

Before Linnaeus worked out his system, botanists and other scientists tried various different ways of describing plants and animals so that other scientists knew what was being discussed. They gave each plant or animal a name, usually in Latin, that described it as closely as possible. But because the descriptions sometimes had to be really elaborate to indicate differences between closely related species, the names got unwieldy—sometimes nine or ten words long.

Carl Linnaeus sorted this out first by sorting out taxonomy, or how living creatures are related to each other. It seems pretty obvious to us now that a cat and a lion are related in some way, but back in the olden days no one was certain if that was the case and if so, how closely related they were. It’s taken hundreds of years of intensive study by thousands upon thousands of scientists and dedicated amateurs to get where we are today, not to mention lots of technological advances. But Linnaeus was the first to really attempt to codify different types of animals and other organisms depending on how closely they appeared to be related, a practice called taxonomy.

Linnaeus’s system is beautifully simple. Each organism receives a generic name, which indicates what genus it’s in, and a specific name, which indicates the species. This conveys a whole lot of information in just two words. A zoologist who hears the name Stenella longirostris will know that it belongs to the genus Stenella, which means it’s a type of dolphin, which means it’s in the family delphinidae. If they’re familiar with dolphins they’ll also know they’re talking about the spinner dolphin, and in this case they can even get an idea of what it looks like, since the specific name longirostris means ‘long beak.’ To make things even clearer, a subspecies name can be tagged on the end, so Stenella longirostris centroamericana is a subspecies of spinner dolphin that—you guessed it—lives in the ocean around Central America.

Carl Linnaeus was a young man when he started working out his classification system. He was only 25 when he traveled to Lapland on a scientific expedition to find new plants and describe them for science. This was in 1732 so travel was quite difficult. Linnaeus traveled on horseback and on foot, which as you can imagine took a long time and gave him lots of time to think. Within three years he had worked out the system we still use today.

You know what else Linnaeus invented? The index card. He needed index cards to keep track of all the animals and plants he and other scientists named using his binomial nomenclature system.

Linnaeus named a whole lot of plants and animals himself—something like ten thousand of them during his lifetime. And naturally enough, some mistakes crept in that have since been corrected. But a couple of his mistakes have led to mysteries, and those are the ones we’re going to look at today.

In 1753 Linnaeus got to examine a fetal elephant preserved in a jar of alcohol. Back then hardly anyone outside of Asia and Africa had seen an elephant, so Linnaeus was enormously excited about it and wrote to a friend that the specimen was as rare as a diamond.

Linnaeus described the species and named it Elephas maximus, also known as the Asian elephant today. But from records that still survive, the specimen was marked as having come from Africa. A Dutch pharmacist and collector had acquired the specimen around 1736, and after he died it was sold to King Adolf Frederick of Sweden, who let Linnaeus examine it. The auction catalog where it was listed for sale indicates that it was from Africa, but in his official description of the elephant Linnaeus wrote that it was from Ceylon, which is now called Sri Lanka, which is in Asia.

So ever since there’s been a mystery as to whether the elephant specimen was actually an Asian elephant or an African elephant, and if Linnaeus even knew that there were elephants in Africa. Because the specimen is of a fetal elephant—that is, a baby that died before it was fully developed, probably when its mother was killed while she was pregnant—it’s hard to tell just by looking if the specimen is an African or Asian elephant. We do still have the specimen, fortunately, which is held in the Swedish Natural History Museum’s collection.

A mammal expert at the London Natural History Museum, named Anthea Gentry, got curious about the specimen in 1999, when she saw it on a trip to Sweden. Gentry’s husband was a paleontologist who specialized in mammals, and later she showed him a photograph of the specimen and asked what he thought. He said he was pretty sure it was an African elephant, not an Asian elephant. Gentry got permission to do DNA testing on the specimen, but since it had been in alcohol for so long, not even the most advanced technology and the world’s most experienced expert in ancient DNA could get a usable genetic sequence from the tissue.

The world’s most experienced expert in ancient DNA was Tom Gilbert of the University of Copenhagen in Denmark. He did his best and failed, but he couldn’t forget about the little mystery elephant. In 2009 he got an idea for extracting genetic material from the specimen in a new way that might yield results. It took years, but he and his team got it to work. In 2012 the mystery was finally solved. Linnaeus’s little elephant was actually an African elephant.

But that’s not the end of the story. When a scientist describes a new species and gives it its scientific name, the first specimen described is known as the type specimen. Linnaeus’s elephant was the type specimen of the Asian elephant—but since it was proven to be an African elephant, it couldn’t continue to be the type specimen of the Asian elephant. But that meant that there was no official type specimen of the Asian elephant. They needed a specimen that was still available and that had been described by someone who had examined it scientifically.

When an animal is described officially, it’s a formal process. The International Commission on Zoological Nomenclature decides whether a suggested name is acceptable and makes decisions on type specimens and taxonomy. So researchers connected with the Commission started digging around for a new type specimen, preferably one from Linnaeus’s time or earlier.

A type specimen isn’t always a whole animal. A lot of times it’s just a little piece of a skeleton or a partial fossil, although the more complete a specimen is, the better. Linnaeus had described a partial elephant tooth at some point which was still available in a Swedish museum, and taxonomists were considering using that as a type specimen when they got an email from a paleontologist who specialized in elephants. He sent a copy of a travel journal from an amateur naturalist named John Ray, who had visited Florence in 1664 and wrote his observations of an elephant skeleton and skin on display in the duke’s palace.

And, it turned out, the elephant skeleton John Ray had described was in the collection of a museum in Florence. And it was definitely the skeleton of an Asian elephant—in fact, we even have what amounts to a photograph of the elephant when it was alive, because none other than the artist Rembrandt sketched it. So that skeleton was designated as the type specimen of the Asian elephant and all is well.

That brings us to the other mystery associated with Linnaeus, and this one is a lot less cute than a misidentified baby elephant. But before I tell you what the mystery animal is, let me tell you something that happened to Linnaeus before he’d even come up with his system of nomenclature. This happened in 1728, when Linnaeus was a broke college student staying with a professor and spending all his free time collecting botanical specimens in the marshes.

One day Linnaeus was searching for plants he didn’t already have specimens of when something stung him on the neck. Since he was wading around in a marsh, this was not really that unusual. But this wasn’t the usual insect sting or midge bite. Before long Linnaeus’s neck was painfully swollen, and soon one of his arms had swollen up too.

These days we’d recognize this as an allergic reaction, but back in 1728 they didn’t know what allergies were. By the time Linnaeus got home, he was in such bad shape that the doctor they called worried he wouldn’t survive.

Fortunately for Linnaeus and for science and humanity in general, he survived and went on to invent his naming system only eight years later. Some thirty years after he almost died, he published the tenth edition of his book, Systema Naturae, and included a formal description of the animal that had almost killed him. He named it the fury worm, Furia infernalis.

But there was no type specimen of a fury worm. Linnaeus hadn’t seen the one he believed had bitten him, and the only one anyone had shown him was a tiny worm so dried up and old that he couldn’t see any details. But he knew the fury worm existed because it had bitten him, and anyway everyone knew it was a real animal.

The fury worm was supposed to be tiny and slender, so small that it could be picked up by the wind and blown to other places. If it landed on a person or an animal it would immediately bite them with its sharp mouthparts, breaking the skin, then burrow into the flesh through the wound. It would dig in so quickly and so deeply that it was impossible to find, and even if you did find it, it was impossible to get out because of the backward-pointing bristles on its tail that kept it anchored in place. A person or animal bitten by the worm was likely to die within a day, sometimes within half an hour, unless a poultice of cheese or curds was applied to the bite.

Fortunately for most of the world, this horrible worm only lived in swampy areas in northern Sweden and Finland, Russia, and a few other nearby areas. In one year, 1823, some 5,000 reindeer died from fury worm attacks, and the export of reindeer furs was banned so the worm wouldn’t spread.

But. Where. Are. The. Worms??? And why would a parasitic worm kill its host so quickly? A parasite depends on its host staying alive for enough time that the parasite can benefit from whatever it’s getting from the host, whether that’s nutrients or a protected place to develop into its next life stage. This isn’t going to happen in half an hour.

So we have all this anecdotal evidence of the fury worm’s existence, even from such noted a scientist as Linnaeus himself, but no worms. And the symptoms reported from fury worm attacks varied quite a lot from patient to patient.

Doubts about the fury worm’s existence were already common in the 19th century, and even back in the late 18th century Linnaeus started to have doubts. And as technology and scientific knowledge improved, the fury worm started to look less and less like a real animal and more and more like an explanation for things people had once not understood—like allergies, infection, and bacteria. The death of 5,000 reindeer in 1823 was finally traced to a disease called neurocysticercosis [neuro-cyst-iser-kosis], which is actually caused by a parasite, but not a fury worm. It’s caused by tapeworm larvae that only kill its host after the larvae have matured and are ready to infect a new animal, which happens when something eats the meat of the animal that has died.

So was the fury worm ever a real animal? Almost certainly not. I tried to find out if people are still reporting fury worm bites in northern Sweden and Finland, but I didn’t come up with anything. On the other hand, I did check and it doesn’t look like there’s a band named Furia infernalis, so if you were trying to think of a really cool name for your band, I got you.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

 

Episode 122: Strange Shark Ancestors

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This week let’s learn about some ancestors of sharks and shark relatives that looked very strange compared to most sharks today!

Stethacanthus fossil and what the living fish might have looked like:

Two Falcatus fossils, female above, male below with his dorsal spine visible:

Xenacanthus looked more like an eel than a shark:

Ptychodus was really big, but not as big as the things that ate it:

A Helicoprion tooth whorl and what a living Helicoprion might have looked like:

Show transcript:

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

This week we’re going back in time again to learn about some animals that are long-extinct…but they’re not land animals. Yes, it’s a weird fish episode, but this one is about shark relatives!

The first shark ancestor is found in the fossil record around 420 million years ago, although since all we have are scales, we don’t know exactly what those fish looked like. The first true shark was called Cladoselache [clay-dough-sell-a-kee] and lived around 370 million years ago, at the same time as dunkleosteus and other massive armored fish. We covered dunkleosteus and other placoderms back in episode 33. Cladoselache grew up to four feet long, or 1.2 meters, and was a fast swimmer. We know Cladoselache ate fish because we have some fossils of Cladoselache with fish fossils in the digestive system—whole fish fossils, which suggests that cladoselache swallowed its prey whole. Cladoselache also had fin spines in front of its dorsal fins that made the fins stronger, but unlike its descendants, it didn’t have denticles in its skin. It didn’t have scales at all.

The denticles in shark skin aren’t just protection for the shark, they also strengthen the skin to allow for the attachment of stronger muscles. That’s why sharks are such fast swimmers.

[Jaws theme]

Stethacanthidae was a family of fish that went extinct around 300 million years ago. It was related to ratfish and their relatives, including sharks. Stethacanthus is the most well-known of the stethacanthidae. It grew a little over 2 feet long, or 70 cm, and was probably a bottom-dwelling fish that lived in shallow waters. It ate crustaceans, small fish, cephalopods, and other small animals.

We have some good fossils of various species of Stethacanthidae and they show one feature that didn’t get passed down to modern ratfish or sharks. That’s the shape of its first dorsal fin, the one that in shark movies cuts through the water just before something awful happens.

[Jaws theme again]

Stethacanthidae’s dorsal fin was really weird. It was shaped sort of like a scrub brush on a pedestal, with the bristles sticking upwards, which is sometimes referred to as a spine-brush complex. Researchers aren’t sure why its fin was shaped in such a way, but since it appears that only males had the oddly shaped fin, it was probably for display. It also had a patch of the same kind of short bristly denticles on its head. Males also had a long spine that grew from each pectoral fin that was probably also for display. Some researchers think the males fought each other by pushing head to head, possibly helped by the odd-shaped dorsal fin.

In the past, before researchers figured out that only the males had the strange dorsal fin, some people suggested that the fish may have used the fin as a sucker pad to attach to other, larger fish and hitch a ride. This is what remoras do. Remoras have a modified dorsal fin that is oval-shaped and acts like a sucker. The oval contains flexible membranes that the remora can raise or lower to create suction. The remora attaches to a larger animal like a shark, a whale, or a turtle and lets the animal carry it around. In return, the remora eats parasites from the host animal’s skin. But remoras aren’t related to sharks.

Other shark relatives had dorsal spines. Falcatus falcatus lived about the same time as Stethacanthus, around 325 million years ago. It grew up to a foot long, or 30 cm, and ate shrimp, fish, and other small animals. We have so many fossils of falcatus from the Bear Gulch Limestone deposits in Montana that we know quite a bit about it. It probably detected prey with electroreceptors on its snout like many modern sharks do, and it was probably a fast swimmer that could dive deeply. Its eyes are unusually large for a shark too. Females would have looked like a small, slender sharklike fish, but males had a spine that grew forward from just behind its head, sort of like a single bull’s horn. It’s called a dorsal spine and is actually a modified dorsal fin. It was probably for display, although males may have also used it to fight each other. We have a well preserved fossil of a pair of falcatus together, a male and female, where it looks like the female may be biting the male’s dorsal spine. Some researchers suggest the spine was used in a pre-mating ritual, but it’s probable that the fish just happened to die next to each other and no one was actually biting anyone.

Another shark relative with a dorsal spine is Hybodus, which grew up to 6 ½ feet long, or 2 meters. Hybodus was a successful genus of cartilaginous fish that lived from around 260 million years ago up to 66 million years ago. Researchers think its dorsal spine was used for defense since both males and females had the spine. Hybodus would have looked like a shark but its mouth was relatively small. It probably ate small fish and squid, catching them with the sharp teeth in the front of its mouth, but it also probably ate a lot of crustaceans and shellfish, which it crushed with the flatter teeth in the rear of its mouth.

Xenacanthus had a dorsal spine too, but it was a much different shark ancestor from the ones we’ve talked about so far. It lived until about 208 million years ago in fresh water. It grew to about three feet long, or one meter, and would have looked more like an eel than a shark. It was slender with an elongated body, and its dorsal fin was short but extended along the back down to the pointed tail. This suggests it probably swam like an eel, since eels have a similar fin structure. It probably ate crustaceans and other small animals.

Xenacanthus’s spine grew from the back of the skull and, unusually for a shark relation, it was made of bone instead of cartilage. Both males and females had the spine and some researchers suggest that it may have been venomous like a sting ray’s tail spine.

Rays are closely related to sharks, and if you want to see a fish that makes every single weird extinct shark look normal, just look at a sawfish. The sawfish is a type of ray and it’s alive today, although it’s endangered. I’m going to do a whole episode on rays pretty soon so I won’t go into detail, but the sawfish isn’t the only fish alive today with a long snout with teeth that stick out on either side. The sawshark is related to the sawfish but is actually a shark, not a ray. And there’s a third type of fish with a saw, related to both sawfish and sawsharks, called the Sclerorhynchidae. Sclerorhynchids went extinct around 55 million years ago and are considered part of the ray family, although they’re not ancestors of living rays. Sclerorhynchids grew around three feet long, or about a meter, and probably looked a lot like modern sawfish although with a rostrum, or snout, that was more pointed and less broad than most sawfish rostrums. The teeth that stuck out to either side were also relatively small. Researchers think Sclerorhynchids used their saws the same way modern sawfish and sawsharks do, to find small animals living on or near the bottom in shallow water and slash them to death before eating the pieces.

[Jaws theme again]

Most of the shark relatives we’ve talked about so far were pretty small, certainly compared to sharks like the great white or megalodon, which by the way we covered in episode 15 along with the hammerhead shark. But a shark called Ptychodus grew up to 33 feet long, or ten meters. It went extinct about 85 million years ago. Its dorsal fin had serrated spines and its mouth had lots and lots of really big teeth–up to 550 teeth, but they weren’t sharp. Instead, they were flattened with riblike folds that helped Ptychodus crush the mollusks it ate. It probably also ate squid and crustaceans, along with any carrion it might come across. It lived at the bottom of the ocean, but in relatively shallow areas where there were plenty of mollusks but not too many mosasaurs or other sharks that might treat Ptychodus as a nice big meal.

In episode 33, the one about dunkleosteus, we also talked about helicoprion and some of its relations. Helicoprion looked like a shark but was actually less closely related to true sharks than to ratfish. Helicoprion lived until about 250 million years ago and some researchers estimate it could grow up to 24 feet long, or 7.5 meters.

Instead of a weird dorsal fin, helicoprion had weird teeth. Weird, weird teeth. It had a tooth whorl instead of the regular arrangement of teeth, where its teeth grew in a spiral that seems to have been situated in the lower jaw. It looked like the blade of a circular saw. Now, this is bizarre but it’s not really all that much more bizarre than sawfish teeth, which aren’t even inside the mouth and stick out sideways. But the frustrating thing for researchers is that we still don’t have any helicoprion fossils except for the teeth whorls and part of one skull. Like most sharks and shark relatives, almost all of helicoprion’s skeleton was made of cartilage, not bone, and cartilage doesn’t fossilize very well. So even though helicoprion was widespread and even survived the Permian-Triassic extinction event, we don’t know what it looked like or what it ate or how exactly its tooth whorl worked. But I think it’s safe to say that it would not be good to be bitten by helicoprion.

[stop playing the Jaws theme omg]

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

[Jaws theme again]