Category Archives: fossils

Episode 329: Manatees and a Surprise Sloth

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Thanks to Alexandra and Pranav for their suggestions this week! Let’s learn about manatees and sloths, including a surprising extinct sloth.

Further reading:

Sloths in the Water

A West Indian manatee:

A three-toed sloth:

Show transcript:

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

This week we have a suggestion from Alexandra and Pranav, who wanted an episode about manatees. We’ll also talk about another marine mammal, a weird extinct one you may never have heard of.

The manatee is also called the sea cow, because it sort of slightly resembles a cow and it grazes on plants that grow underwater. It’s a member of the order Sirenia, which includes the dugong, and sirenians are probably most closely related to the elephant. This sounds ridiculous at first, but there are a lot of physical similarities between the manatee and the elephant. Their teeth are very similar, for instance, even if the manatee doesn’t grow tusks. The elephant has a pair of big chewing teeth on each side of its mouth that look more like the bottoms of running shoes than ordinary teeth. Every so many years, the four molars in an elephant’s mouth start to get pushed out by four new molars. The new teeth grow in at the back of the mouth and start moving forward, pushing the old molars farther forward until they fall out. The manatee has this same type of tooth replacement, although its teeth aren’t as gigantic as the elephant’s teeth. The manatee also has hard ridged pads on the roof of its mouth that help it chew its food.

Female manatees are larger than males on average, and a really big female manatee can grow over 15 feet long, or 4.6 meters. Most manatees are between 9 and 10 feet long, or a little less than 3 meters. Its body is elongated like a whale, but unlike a whale it’s slow, usually only swimming about as fast as a human can swim. Its skin is gray or brown although often it has algae growing on it that helps camouflage it. The end of the manatee’s tail looks like a rounded paddle, and it has front flippers but no rear limbs. Its face is rounded with a prehensile upper lip covered with bristly whiskers, which it uses to find and gather water plants.

Every so often a manatee will eat a little fish, apparently on purpose. Since most herbivorous animals will eat meat every so often, this isn’t unusual. Mostly, though, the manatee spends almost all of its time awake eating plants, often from the bottom of the waterway where it lives. It lives in shallow water and will use its flippers to walk itself along the bottom, and also uses its flippers to dig up plants. Its upper lip is divided in two like the upper lips of many animals, which you can see in a dog or cat as that little line connecting the bottom of the nose to the upper lip. In the manatee, though, both sides of the lips have a lot of muscles and can move independently.

There are three species of manatee alive today: the West Indian manatee that lives in the Gulf of Mexico down to the eastern coast of northern South America, the Amazonian manatee that lives exclusively in fresh water in the Amazon basin, and the West African manatee that lives in brackish and fresh water. Sometimes the West Indian manatee will also move into river systems to find food.

Back in episode 153 we talked about the Florida manatee, which is a subspecies of West Indian manatee. In the winter it mostly lives around Florida but in summer many individuals travel widely. It’s sometimes found as far north as Massachusetts along the Atlantic coast, and as far west as Texas in the Gulf of Mexico, but despite its size, the manatee doesn’t have a lot of blubber or fat to keep it warm. The farther away it travels from warm water, the more likely it is to die of cold.

In the 1970s there were only a few hundred Florida manatees alive and it nearly went extinct. It was listed as an endangered species and after a lot of effort by a lot of different conservation groups, it’s now only considered threatened, but it’s still vulnerable to habitat loss, injuries from boats, and getting tangled in fishing gear and drowning. Occasionally a crocodile will eat a young manatee, but for the most part it’s so big, and lives in such shallow water, that most predators won’t bother it. It basically only has to worry about humans, and unfortunately humans still cause a lot of manatee deaths every year with boats.

A lot of times, a manatee that’s hit by a boat is only injured. There are several rehabilitation centers in the United States, where an injured manatee can be treated by veterinarians until it’s healed and can be reintroduced into the wild.

One other detail that makes the manatee similar to the elephant is its flippers, which is probably not what you expected me to say. Most manatees have toenails on their flippers that closely resemble the nails on elephant feet. The exception is the Amazonian manatee that doesn’t have toenails at all.

A lot of the food the Amazonian manatee eats actually floats on the surface of the rivers where it lives, and it will also eat fruit that drops into the water. Because the Amazon basin is subject to a dry season where there’s not a lot of food, the manatee eats a lot when it can to build up fat reserves for later. During the dry season, it usually moves to the biggest lakes in the area as the rivers and shallower lakes dry up or get too shallow for the manatee to swim in. Since the manatee has a low metabolic rate, it can live off its fat reserves until the dry season is over.

One interesting thing about the manatee is that it only has six vertebrae in its neck. Almost all other mammals have seven, even giraffes. The exception is the two-toed sloth, which also has six, and the three-toed sloth, which has a varying number of neck vertebrae, up to nine in some species!

Pranav also wanted to learn about sloths, so let’s talk about them next. All sloths are native to Central and South America. The sloths living today live in forests, especially rainforests, and spend almost all their time in trees.

A sloth makes the manatee look like a speed demon. It spends most of its time hanging from its long claws beneath branches, eating leaves and other plant material, but when it does move, it does so extremely slowly. This helps it stay camouflaged from predators, because its fur contains algae that makes it look green, so a barely-moving green-furred sloth hanging from a tree just looks like a bunch of leaves. It does move from one tree to another to find fresh leaves, and once a week it climbs down from its tree to defecate and urinate on the ground. Yes, it only relieves itself once a week.

The sloth’s digestive tract is also extremely slow, which allows it to extract as much nutrition as possible from each leaf. It takes about a month for a sloth to fully digest one mouthful of food.

The three-toed sloth is about the size of a large cat while the two-toed sloth is slightly larger, maybe the size of a small to medium-sized dog. The two-toed sloth is nocturnal while the three-toed sloth is mostly diurnal. Even though they look and act very similar, the two types of sloth are not very closely related. Both have long curved claws and strong pulling muscles, although their pushing muscles are weak. This is why a sloth can’t walk like other animals; the muscles that would allow it to do so aren’t strong enough to support its own weight. And yet, it can hang from a branch and walk along it for as long as it needs to. I don’t think I could hang from a branch by my fingers for five minutes without having to let go.

Surprisingly, the sloth can also swim quite well, which allows it to find new trees even if there are streams or rivers in the way. But a few million years ago, a different type of sloth lived off the coast of western South America and did a whole lot of swimming. In fact, later species of Thalassocnus were probably fully marine mammals.

We talked about Thalassocnus briefly way back in episode 22. It was related to the giant ground sloths that were themselves related to the living three-toed sloths. The earliest Thalassocnus fossils are of semi-aquatic animals that grazed in shallow water. Fossils from more recent species show increasing adaptations to deeper water, including increased weight of the skeleton to help it stay underwater instead of bobbing up to the surface.

Thalassocnus eventually evolved a stiff, partially fused spine, which reflects the unusual way it moved around underwater. Instead of swimming the way a whale does, or even the way a dog or person does, it moved more like a hippopotamus. Hippos sort of bounce along underwater, using their feet to push off from the bottom. Thalassocnus probably did this too and used its long tail to help it maneuver.

Thalassocnus was a lot bigger than modern sloths. Even the smallest known species were the size of a big human, and the biggest species grew up to 11 feet long, or 3.3 meters. That biggest species was the one that lived most recently, up to about 1.5 million years ago, and researchers think it was fully aquatic. Its nostrils were on the top of its snout and it had prehensile lips to help it find plants underwater. Some researchers even think it could have had a short trunk something like a tapir. It had seven neck vertebrae, as in most other mammals.

There’s still a lot we don’t know about Thalassocnus, but because we have fossils of five different species that lived at different times, scientists are able to determine a lot about how it developed from a mostly terrestrial animal to a mostly or fully marine animal. The youngest species had smaller, weaker legs than the earlier ones, which suggests it didn’t use its legs to walk on land. It probably lived a lot like modern manatees, finding sea grasses and other plants on the sea floor in shallow water, but not able to swim very fast.

One last thing about the manatee is that it spends about half of its time asleep, and it sleeps underwater. It comes up for a breath every 15 minutes or so. Modern sloths sleep a lot too, around 15 hours a day. Chill sleepy friends.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 328: Giant Ants

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Thanks to Richard from NC for suggesting Titanomyrma!

Further reading:

‘Giant’ ant fossil raises questions about ancient Arctic migrations

A fossilized queen Titanomyrma ant with a rufous hummingbird (stuffed) for scale:

Show transcript:

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

This week we have a suggestion from Richard from North Carolina, who sent me an article about an extinct giant ant called Titanomyrma. This episode is short, but I think you’ll find it interesting.

We’ve talked about ants in previous episodes, most recently episode 185. Most ant colonies consist of a single queen ant who lays all the eggs for her colony, seasonally hatched males with wings who fly off as soon as they’re grown, and worker ants. The worker ants are all female but don’t lay eggs. Army ants have another caste, the soldier ant, which are much larger than the worker ants and have big heads and strong, sharp mandibles. In many species of ant, the worker ants are further divided into castes that are specialized for specific tasks.

The biggest species of ant alive today is probably the giant Amazonian ant. The workers can grow over 1.2 inches long, or more than 3 cm, which is huge for an ant. It lives in South America in small colonies, usually containing less than 100 workers, and unlike most ants it doesn’t have a queen. Instead, one of the workers mates with a male and lays eggs for the colony. The giant Amazonian ant can sting and its sting contains venom that causes intense pain for up to two days. Fortunately, you will probably never encounter these giant ants, and even if you do they’re not very aggressive.

Another contender for the biggest species of ant alive today is the Dorylus genus of army ants, also called driver ants, which we talked about in episode 185. It lives in Africa in colonies that have millions of members, and the queen is the largest ant known. A queen army ant can measure 2.4 inches long, or 63 millimeters, but worker ants are much smaller.

Around 50 million years ago, giant ants related to modern driver ants lived in both Europe and North America. The genus is Titanomyrma and three species are known so far, found in Germany, England, Canada, and the American states of Tennessee and Wyoming.

The Wyoming ant fossil was discovered years ago and donated to the Denver Museum of Nature and Science, where it was stored in a drawer and forgotten about. In 2011 a curator found it and showed it to a paleoentomologist named Bruce Archibald. Dr. Archibald recognized it immediately as a fossilized queen ant even though it was the size of a hummingbird. He also realized it was very similar to a type of giant ant that once lived in Germany.

The German discovery was the first Titanomyrma species discovered, and it’s also the biggest known so far. The queen Titanomyrma gigantea grew up to 2.8 inches long, or 7 centimeters. Males grew up to 1.2 inches long, or 3 cm. The fossilized queen ants found have wings, with a wingspan of over 6 inches, or 16 cm. The other two known species are generally smaller, although still pretty darn big for ants.While they’re not that much bigger than the living Dorylus queens, most of the size of a queen Dorylus ant comes from her enlarged abdomen. Titanomyrma ants were just plain big all over.

Titanomyrma didn’t have a stinger, so it’s possible it used its mandibles to inflict bites, the way modern army ants do. It might also have sprayed formic acid at potential predators, as some ants do today.

The biggest ants alive today all live in tropical areas, so researchers thought Titanomyrma probably did too. During the Eocene, the world was overall quite warm and parts of Europe were tropical. The northern hemisphere supercontinent Laurasia was in the process of breaking up, but Europe and North America were still connected by the Arctic. Even though the Arctic was a lot warmer 50 million years ago than it is now, it was still too cold for a tropical ant. If Titanomyrma couldn’t survive in cold weather, how did it spread from one continent to another when it had to go through the Arctic?

There were warming periods during the Eocene that lasted a few hundred thousand years at a time, so researchers thought the ants probably migrated through the Arctic while it was warmer than usual. Then, in early 2023, a fossilized Titanomyrma queen ant was discovered in Canada. Because the rock it was preserved in has been distorted over the years, we can’t be certain how big the ant actually was. What we do know, though, is that the ant lived in a mountainous area that could get quite chilly, very different from the tropical climate scientists thought the giant ants needed.

As a result of the new finding, researchers are reconsidering whether the giant ants that lived 50 million years ago were really all that similar to modern giant ants. Just because the biggest ants alive today require tropical climates doesn’t mean that ancient giant ants did.

Hopefully more giant ant fossils will turn up soon, so we can learn more about where they lived, how they lived, and precisely how big they could get.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 325: The Burrunjor

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We have merch available again!

Thanks to Will for suggesting this week’s topic, the burrunjor!

Muttaburrasaurus had a big nose [picture by Matt Martyniuk (Dinoguy2) – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=3909643]:

The “rock art” that Rex Gilroy “found”:

Show transcript:

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

Recently, Will suggested we learn about an Australian cryptid called the burrunjor. As it happens, this is a short chapter in my book Beyond Bigfoot & Nessie: Lesser-Known Mystery Animals from Around the World, which is available to buy if you haven’t already. I’ve updated it a little from the chapter, so even if you have the book I think you’ll find this a fun episode.

Dinosaurs once lived in what is now Australia, just as they lived throughout the rest of the world. Similar to the southwestern United States reports of little living dinosaurs that we talked about in episode 252, some people in northern Australia report seeing living dinosaurs running around on their hind legs—but these dinosaurs aren’t so little.

The burrunjor, as it’s called, is often described as looking like a Tyrannosaurus rex. Mostly, though, people don’t actually see it. Instead, they hear roaring or bellowing and later see the tracks of a large, three-toed animal that was walking on its hind legs.

One Australian dinosaur that people mention when trying to solve the mystery of the burrunjor is Muttaburrasaurus. It was an ornithopod that grew up to 26 feet long, or 8 meters. It walked on its hind legs and had a big bump on the top of its muzzle that made its head shape unusual. No one’s sure what the bump was for, but some scientists speculate it might have been a resonant chamber so the animal could produce loud calls to attract a mate. Other scientists think it might have just been for display. Or, of course, it might have been both—or something else entirely. None of the Australian dinosaur sightings mention a big bump on the dinosaur’s nose. Muttaburrasaurus also had four toes on its hind feet, not three, and it disappeared from the fossil record about 103 million years ago. It also probably ate plants, not meat.

Another suggestion is that the burrunjor is a megaraptorid that survived from the late Cretaceous. These dinosaurs looked like theropods but with longer, more robust arms. Most scientists these days group them with the theropods. Most of the known specimens are from what is now South America, but two species are known from Australia, Australovenator and Rapator.

Australovenator is estimated as growing up to 20 feet long, or 6 meters, and probably stood about the same height as a tall human. It was a fast runner and relatively lightly built. It disappeared from the fossil record around 95 million years ago, not that we have very many bones in the first place. We only know Rapator from a single bone dated to 96 million years ago. It was probably related to Australovenator, although some paleontologists think Australovenator and Rapator are the same dinosaur. Either way, it’s doubtful that any of these animals survived the extinction event that killed off all the other non-avian dinosaurs.

“Burrunjor” is supposed to be a word used by ancient Aboriginal people to describe a monstrous lizard that eats kangaroos. But in actuality, Burrunjor is the name of a trickster demigod in the local Arnhem Aboriginal tradition and has nothing to do with reptiles or monsters. The Aboriginal rock art supposedly depicting a dinosaur-like creature doesn’t resemble other rock art in the region and isn’t recognized by researchers or Aboriginal people as being authentic.

All accounts of the burrunjor trace back to a single source, an Australian paranormal writer named Rex Gilroy. Gilroy was the one who “discovered” the rock art of a supposed dinosaur and none of the sightings he reports appear in local newspapers. The first mention of the word burrunjor referring to a monster appears in 1995, when Gilroy’s book Mysterious Australia was first published. According to Gilroy, the most recent burrunjor sighting is from 1985, when a family driving to Roper River reported seeing a feather-covered dinosaur that was 20 feet long, or 6 meters. But again, that report doesn’t appear in the newspapers, just in Gilroy’s books.

Gilroy’s burrunjor is probably a hoax, but there is a big lizard in Australia that sometimes stands on its hind legs. Monitor lizards live throughout Australia and are often called goannas. The largest Australian species can grow over 8 feet long, or 2.5 meters. All monitor lizards, including the Komodo dragon that lives in Indonesia, can stand on their hind legs. The lizard does this to get a better look at the surrounding area. It uses its tail as a prop to keep it stable and can’t actually walk on its hind legs, but an 8-foot lizard standing on its hind legs might look like a dinosaur from a distance.

An even bigger monitor lizard, called Megalania, lived in Australia until at least 50,000 years ago and maybe much more recently. It’s possible that Aboriginal Australians lived alongside it, although there’s no evidence for this either way. (Unless you count the evidence that that would be really really cool.)

Megalania is considered the largest terrestrial lizard known. Dinosaurs weren’t lizards and crocodilians aren’t either, but monitor lizards are. We don’t have any complete fossils of Megalania but its total length, including its tail, is estimated to be as much as 23 feet long, or 7 meters. This is more than twice the length of the Komodo dragon, the largest lizard alive today and a close relation. Like the Komodo dragon, Megalania was probably venomous.

As for Rex Gilroy, he recently passed away at the age of 79 and his books about the burrunjor are out of print. Rest in peace, burrunjor man.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 324: The Tenrec and Adalatherium

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We have merch available again!

Thanks to Eva and Leo for suggesting the tenrec!

Further reading:

Marooned on Mesozoic Madagascar

Introduction to Adalatherium hui

The lowland streaked tenrec:

The hedgehog tenrec rolls up just like an actual hedgehog [photo by Rod Waddington, CC BY-SA 2.0, via Wikimedia Commons]:

Actual hedgehog, not a tenrec:

Lesser hedgehog tenrec REALLY looks like an actual hedgehog [By Wilfried Berns www.Tierdoku.com – Transferred from de.wikipedia to Commons.Orig. source: eigene Fotografie, CC BY-SA 2.0 de, https://commons.wikimedia.org/w/index.php?curid=2242515]:

Adalatherium:

Show transcript:

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

This week we’re going to learn about a weird little animal suggested by both Eva and Leo, the tenrec of Madagascar. While we’re at it, we’re going to learn about another little animal found on Madagascar a long time ago that’s one of the weirdest mammals ever discovered.

Before we get started, though, someone sent me a book! If your name is Jennifer or someone named Jennifer mailed this book to me for you, thank you! The book is called The Last Flight of the Scarlet Macaw: One Woman’s Fight to Save the World’s Most Beautiful Bird by Bruce Bercott. Thank you so much! I did not know when I started this podcast over six years ago that one of the benefits of doing an animal podcast is sometimes people send you books about animals, which is the best thing in the world. There’s no note so I thought I’d give you a shout-out on the podcast.

As we learned in episode 318, about 88 million years ago, the island of Madagascar broke off from every other landmass in the world, specifically the supercontinent Gondwana. The continent we now call Africa separated from Gondwana even earlier, around 165 million years ago. Madagascar is the fourth largest island in the world and even though it’s relatively close to Africa these days, many of its animals and plants are much different from those in Africa and other parts of the world because they’ve been evolving separately for 88 million years.

But at various times in the past, some animals from Africa were able to reach Madagascar. We’re still not completely sure how this happened. Madagascar is 250 miles away from Africa, or 400 kilometers, and these days the prevailing ocean currents push floating debris away from the island. In the past, though, the currents might have been different and some animals could have arrived on floating debris washed out to sea during storms. During times when the ocean levels were overall lower, islands that are underwater now might have been above the surface and allowed animals to travel from island to island until they reached Madagascar.

Sometime between 25 and 40 million years ago, a semiaquatic mammal reached Madagascar in enough numbers that it was able to establish itself on the island. It was related to the ancestors of a semiaquatic mammal called the otter-shrew, even though it’s neither an otter nor a shrew. The otter-shrew lives in parts of Africa and is pretty weird on its own, but we’ll save it for another episode one day. The otter-shrew’s relative did so well in its new home of Madagascar that over the millions of generations since, it developed into dozens of species. We now call these animals tenrecs.

It’s hard to describe the tenrec because the various species are often very different in appearance. There are some things that are basically the same for all species, though. First, the tenrec has a low body temperature, although it varies from species to species and also varies depending on time of year. That’s because some species of tenrec go into torpor when it’s cold, or sometimes full hibernation. During torpor the animal’s body temperature drops even more than usual. The common tenrec hibernates up to nine months out of the year.

Second, the tenrec has a cloaca, which is really unusual in placental mammals. Birds, reptiles, and amphibians have a cloaca, which is a single opening used for excretion and often for giving birth or laying eggs too. Most mammals have separate openings for different uses.

Third, all tenrecs are pretty small with only a little short tail. The biggest is only a little over a foot long at most, or 39 cm, and most are much smaller.

Leo specifically likes the streaked tenrec, so let’s learn about it to give us a better idea of what tenrecs are like in general. There are two species of streaked tenrec and while they live in different parts of Madagascar, they mostly live in tropical rainforests. They’re considered a type of spiny tenrec because they have quills all over like a tiny porcupine or a brightly colored hedgehog. The highland streaked tenrec is black and white, while the lowland streaked tenrec is black and yellow.

The streaked tenrec’s bright coloration gives a warning to potential predators that it is pointy. If a predator doesn’t figure it out, the tenrec will raise its quills and shake them to make a little rattling sound. If that doesn’t stop the predator and it tries to bite the tenrec, the quills can detach and will lodge in the predator’s mouth. That generally gets the point across. (haha, point)

The lowland streaked tenrec also communicates by rubbing its quills together to make ultrasonic sounds. This method of sound production is called stridulation and the streaked tenrec is the only mammal known to make sound this way. It has special muscles at the base of its quills that help it move the quills to make sounds. Stridulation is mostly found in insects, including crickets.

Like most tenrecs, the streaked tenrec has a long, thin snout and short legs. It spends a lot of its time digging for earthworms and other invertebrates, and it also eats fruit. It lives in family groups that sleep in shallow burrows. Also, it’s super cute. Just don’t lick it.

Another tenrec with spines is the hedgehog tenrec, which looks and acts incredibly like a hedgehog even though it’s not related. That’s yet another example of convergent evolution. The lesser hedgehog tenrec and the greater hedgehog tenrec, which by the way belong to different genera, are nocturnal animals that live in open forests, savannas, and people’s gardens in Madagascar. During the day it stays hidden in dead leaves or brush, or in a hollow of a tree trunk, and at night it comes out to find insects and other small animals to eat. If it feels threatened, it will roll up into a ball to protect its belly while turning itself into a very pointy mouthful. Its spines don’t come loose the way the streaked tenrec’s do, but they’re sharp. Sometimes a hedgehog tenrec will back up quickly toward a potential predator. If it backs into the predator’s nose, suddenly the predator discovers it’s not all that hungry and its nose hurts and it’s just going to leave.

Many species of tenrec resemble shrews. They’re smaller than a mouse, which they otherwise resemble except that they have a long nose and short tail, and they don’t have quills. Most tenrecs have 6 or 8 babies at a time, but some have more. The common tenrec can have up to 32 babies at a time. It has 29 teats! That’s the most teats known in any mammal.

All this is amazing, but while I was researching the tenrec I learned about an even weirder animal that lived on Madagascar at the end of the Cretaceous. That animal wasn’t a dinosaur, though. It was a mammal.

It was discovered by a team of paleontologists in 1999, but they didn’t actually know they’d discovered it. They thought the piece of rock only contained a small crocodyliform. When preparation of the specimen started in 2002, the scientist working on it received an incredible surprise. In addition to fossil remains of both an adult and a baby crocodyliform, there was an almost complete, articulated skeleton of a weird mammal. All three animals may have been buried suddenly by debris carried by a flash flood, which is why they’re so well preserved.

Most mammals that lived alongside dinosaurs were really small, maybe the size of rats at most, but Adalatherium was about the size of a cat. It may have actually grown larger than a cat, because the only specimen we have is an individual that wasn’t fully grown. It was built sort of like a little badger, with a broad body, short legs, short tail, and short snout.

Adalatherium is a member of a group of mammals called Gondwanatheria, which arose in the southern hemisphere around the time that the supercontinent Gondwana was breaking apart. We only have a few fossils of these animals so paleontologists still don’t know how they’re related, but Adalatherium is a big deal because it’s so detailed and almost the whole skeleton is preserved. Paleontologists have known for a long time that these Gondwanatheria were probably not related to modern mammals, but until Adalatherium was discovered no one realized just how weird these animals were.

If you could go back in time to look at Adalatherium when it was alive, you might not think it was all that weird. Also, you’d be a little distracted because dinosaurs would probably be trying to eat you. Most of the weird details probably weren’t visible, but they’re very obvious to scientists studying the fossilized bones. For instance, Adalatherium had a lot of vertebrae in its backbone, more than other mammals—at least 30 total thoracic and lumbar vertebrae. Humans have 17 total and cats have 20, to give you a comparison with modern mammals.

Adalatherium also had weird legs, with its front legs not really seeming to match its rear legs. Its front legs are longer with a strong shoulder, while its rear legs are short and bowed. Paleontologists think it might have been a burrowing animal, which would explain why its rear legs are strangely shaped compared to its front legs, but it could probably run pretty fast too. It also had unusual double grooves on its anklebones.

Another weird thing about Adalatherium was its skull. The parts of the skull that made up the nasal cavity had lots of little holes in it, called foramina, for nerves and blood vessels to pass through. This isn’t unusual in itself, but Adalatherium had more foramina than any other mammal ever examined, living or extinct. One of the foramen was on top of the snout and doesn’t match up with anything seen in any other mammal. Adalatherium probably had a whole lot of very sensitive whiskers, but for all we know, all the foramina were for some other sensory structure, one that was unlike any found in modern mammals.

Adalatherium lived at the end of the Cretaceous, and it’s possible it went extinct along with the non-avian dinosaurs. Gondwanatheria in general all went extinct by around 43 million years ago and as far as we know, no living descendants are still around. But we know very little about these interesting mammals. Hopefully more fossils of Gondwanatheria in general, and Adalatherium in particular, will turn up soon so we can learn more.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 322: The Javelina and Other Peccaries

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Thanks to Oceana and Leo for suggesting this week’s episode about the javelina! We’ll even learn about a mystery peccary too.

Further reading:

New Species of Peccary–Pig-Like Animal–Discovered in Amazon Region

A javelina, also called the collared peccary [By Wing-Chi Poon – Own work by uploader; at Cottonwood Campground, Big Bend National Park, Texas, USA, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4394434]:

Show transcript:

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

This week we have a suggestion by Oceana and Leo, the javelina! It’s an animal native to the Americas, also called the collared peccary. We’re going to learn about it and its close relations, including a mystery animal.

The javelina is in the family Tayassuidae, called the New World pigs. The rest of the world’s pigs, including the warthog and the babirusa and the domestic pig, belong to the family Suidae. While the two families are related, the ancestors of the New World pigs, or peccaries, split off from the ancestors of other pigs around 40 million years ago and they’ve been evolving separately for all that time.

Peccaries live throughout almost all of Central and South America up to southwestern North America and some of the Caribbean islands. All peccaries look like little hairy pigs, including a flat-ended pig snout that it uses to root in the ground, small eyes, short tusks, slender legs with cloven hooves, and a thin little tail. It’s relatively small compared to domestic pigs, about the size of a big dog at most, and is covered with a thick coat of bristly hair. When it’s angry or frightened, it can raise the bristles along its back to make it look larger. It also has scent glands that give off a pungent smell, which is how members of the same herd recognize each other, since peccaries have poor eyesight.

Peccaries mostly eat plant material, but they’re omnivores and will eat meat when they find it, from insects and grubs to frogs and even carrion. Because they root around in the ground and leaf litter, they stir up nutrients in a way that benefits other animals and the environment in general. In the case of the javelina, also called the collared peccary, musk hog, or skunk pig, it’s sometimes considered a pest since it will root up people’s flowerbeds and gardens. But the javelina doesn’t know the difference between a garden and a not-garden. It just wants to find some tasty grubs and roots.

Peccaries are social animals that usually live in small herds. The white-lipped peccary is widespread in the forests of Central and South America, and sometimes lives in herds of 300 animals or more, even as many as 2,000 according to some reports. It requires an enormous range as a result, and travels a lot of the day to find new areas to forage. It’s threatened by habitat loss, mostly deforestation. Like other peccaries, it smells sort of skunky and can be aggressive if threatened. It eats a lot of fruit in addition to other plant material, and because it has stronger jaws than the javelina, it can eat seeds and nuts that the javelina can’t, so the two species can coexist in the same environment without competing for the same food sources.

Until 1972, the Chacoan peccary was only known from some fossils found in 1930. Not only did scientists think it was extinct, they thought it had been extinct for a long time. But in the early 1970s, rumors about a new peccary species started to circulate. A team of biologists followed up with locals and discovered the peccary living in a small area of South America called Chaco. Surprise! New peccary just dropped.

The Chacoan peccary, also known as the tagua, looks a lot like a javelina although it doesn’t have a dew claw on its hind feet. It has a tough snout and brown and gray bristles, with white on its shoulders and around its mouth. It lives in small bands of around a dozen individuals that roam across a large range, eating tough vegetation that other animals wouldn’t even consider food—cacti, for instance. A peccary will roll a cactus around on the ground with its snout and hooves, rubbing the spines off so it can eat it. If that doesn’t work, it will pull the spines out with its teeth. Cacti contain acids that other animals can’t digest, but the Chacoan peccary has specialized kidneys that are adapted to break down those acids.

The Chacoan peccary is endangered due to hunting, habitat loss, and disease. The area where it lives is being rapidly deforested to make way for huge cattle ranches. This is bad enough, but when ranchers move in, they want roads to get to their land more easily, and once the roads are in place, not only can more hunters get to the area, but more peccaries are killed by traffic. It’s estimated that only about 3,000 Chacoan peccaries are alive today. The government of Paraguay is trying to reduce the impact of habitat loss by protecting key areas of forest, and breeding populations are kept in a number of zoos across the world.

There are only three living species of peccary known: the javelina, the white-lipped peccary, and the Chacoan peccary. But there may be a fourth, the giant peccary.

In 2000, a Dutch biologist named Marc van Roosmalen was researching animals in Brazil, and as part of his studies he talked to some local hunters. They showed him the hides of three big peccaries, but they looked different from the ordinary javelinas that lived in the area. Van Roosmalen had already spotted some javelinas that he’d thought seemed too big to be ordinary javelinas, so when he saw the hides he started wondering if there were two peccary species in that part of the Amazon region.

He returned in 2003 with a German filmmaker, who got video footage of a group of these mystery peccaries. They even found a skull. Van Roosmalen described the giant peccary as a new species in 2007, but not everyone agreed it was a new species.

The giant peccary is larger than the javelina but otherwise looks and acts very much like it. Since the javelina is common pretty much everywhere that peccaries are found, and can show a lot of variation in size and appearance, many scientists think the giant peccary is just a population of unusually large javelinas.

The giant peccary reportedly lives in pairs or small family groups instead of herds. The local people have a different name for it to differentiate it from the javelina, a name which means “the big javelina that lives in pairs.” But while a genetic study of the skull found in 2003 determined that the giant peccary diverged from all other peccary species around a million years ago, later analysis is less conclusive.

As of 2011, the giant peccary is in a sort of scientific limbo, waiting for more evidence and further studies to determine whether it’s actually a new species or just a bunch of big javelinas. Let’s hope we learn more about it soon and can clear up the mystery.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 321: Archaeopteryx

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We have merch available again!

Thanks to Eilee for suggesting this week’s topic, Archaeopteryx!

Further reading:

Dinosaur feather study debunked

Archaeopteryx fossil provides insights into the origin of flight

An Archaeopteryx fossil [By H. Raab (User: Vesta) – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8066320]:

Show transcript:

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

We’ve had a lot of mammal episodes lately, so this week let’s learn about a reptile…uh, a bird. Not quite a bird, not exactly a reptile. That’s right, it’s an episode about archaeopteryx, a suggestion by Eilee!

A quick note before we start to say that I finally got around to setting up merch again if you want to order a t-shirt or water bottle or whatever with the podcast’s logo on it. I’m using Redbubble this time because they have a lot more items available than our previous vendor. There’s a link in the show notes.

We also have new stickers and those are free, so if you want one, just drop me an email and let me know what your mailing address is. The new sticker is a drawing of a capybara made by me. Anyway, on to the archaeopteryx!

The first archaeopteryx fossils were discovered in Germany in 1861. Before the first skeleton of an archaeopteryx was discovered, though, a single feather impression was found in a limestone quarry that has produced a lot of spectacularly well-preserved fossils. When the full specimen turned up later that same year, palaeontologists decided the feather came from the same animal.

That decision has been questioned repeatedly over the years. A study conducted with laser imaging determined that the single feather was different from the feathers of other archaeopteryx specimens. Results of that study were published in 2019, but in October of 2020 results of a study conducted with a specialized electron microscope determined that the feather did come from an archaeopteryx. The 2020 study also found that the feather was black.

Archaeopteryx lived around 150 million years ago in what is now Europe. It was about the size of a crow but while it looked a lot like a bird, it also looked a lot like a little dinosaur. It had small teeth and a long lizard-like tail. Of the twelve Archaeopteryx fossils found so far, all but one have feather impressions that indicate it had flight feathers on its arms, or rather wings, but at least one specimen also had flight feathers on its legs, which are sometimes referred to as hind wings. These hind wings would have helped it maneuver through branches even though its front wings were limited in their range of motion. It was probably a slow flyer that ate whatever small animals it could catch.

The wing feathers of archaeopteryx were very similar to those of modern birds, and a study published in late 2020 discovered another similarity. Birds molt their feathers and replace them the same way mammals shed hairs and regrow them, but it’s a little trickier for birds. A bird that loses too many feathers from its wings can’t fly until new feathers grow in. Modern birds solve this issue by molting only one pair of wing feathers at a time, and once the replacement grows in, the next pair is shed. The study examined fossilized archaeopteryx wings using a process called laser-stimulated fluorescence imaging, which can reveal details that aren’t otherwise visible. It discovered feather sheaths hidden under what would have been the skin of the wings, ready to grow new feathers. The feather sheaths were the same on both wings and resembled the molting pattern seen in modern falcons.

Archaeopteryx also had feathers on the rest of its body, but they aren’t well preserved so paleontologists can’t determine too much about them. They might have been more fluffy than sleek, like the soft downy feathers in young modern birds, or it might be that the fluffy feathers just happened to be the ones that were most preserved.

Palaeontologists study archaeopteryx because it gives us so much information about how birds evolved from dinosaurs. Archaeopteryx was still very much a dinosaur even though it looked superficially like a bird. Microscopic examination of the fossilized cells and blood vessels inside its bones show that it actually grew very slowly. Modern birds grow extremely quickly when they’re young. One scientist pointed out that when you watch a flock of pigeons, you can’t really tell which ones are fully grown and which ones are still quite young, because baby pigeons grow to an adult size so quickly. Dinosaurs grew to their adult size much more slowly, even the small carnivorous dinosaurs that were ancestral to modern birds. The study determined that Archaeopteryx would probably have taken almost three years to grow to its adult size.

The Archaeopteryx fossil called “specimen number eight” was determined to be a different species from the others, in a study published in 2018. It’s about half a million years younger than the other known specimens and has characteristics found in modern birds that the others don’t have. Its adaptations would have made it a better, more efficient flyer. The differences weren’t noticed before because it’s not a very good specimen and many of the bones are damaged and still embedded in the rock where they can’t be seen. The study used a process called synchrotron microtomography to basically take a 3D scan of the fossil and its rock matrix so scientists can study the scan without breaking the rock open and destroying parts of the fossil.

At the time that archaeopteryx lived, the sea levels were much higher than they are now and Europe was mostly a series of large islands in a shallow sea. The part of Europe that’s now Germany was subtropical but fairly dry, without much rain. All the archaeopteryx specimens have been found in limestone that was once mud at the bottom of a placid lagoon, protected from ocean currents and waves by small islands covered with shrubby vegetation. Archaeopteryx probably lived on these small islands, and while we don’t know how it behaved, many paleontologists think it may have hunted both by running on its long hind legs and by flying, just like a lot of birds do today. We have fossilized remains of little lizards and insects that would have made good meals for a hungry archaeopteryx.

What we do know is that sometimes an archaeopteryx had a very bad day and ended up drowning in the lagoon. On rare occasions, the body floated around until it decomposed enough that it sank into the mud at the bottom. Over millions of years, this mud turned into fine-grained limestone that preserved the fossil archaeopteryx remains in incredible detail.

For a long time, people thought archaeopteryx was a so-called missing link between dinosaurs and birds, and that it was the first bird. We now know that isn’t true. There were other bird-like dinosaurs that could fly before archaeopteryx evolved, although archaeopteryx was a very early flying avian dinosaur.

More importantly, we now know that birds are basically very derived dinosaurs. Dinosaurs had so many features we associate with birds, and birds still have so many features we associate with dinosaurs, that it’s hard to decide whether an animal like archaeopteryx was a bird-like dinosaur or a dinosaur-like bird. I guess it was sort of both.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 318: The Mysterious Malagasy Hippo

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Thanks to the Tracing Owls podcast for this week’s suggestion. I’m a guest on that podcast so make sure to check it out (but while my episode is appropriate for younger listeners, most episodes are not, so be warned).

Further reading:

Huge Hippos Roamed Britain One Million Years Ago

Kenyan fossils show evolution of hippos

The Kilopilopitsofy, Kidoky, and Bokyboky: Accounts of Strange Animals from Belo-sur-mer, Madagascar, and the Megafaunal “Extinction Window”

A sort-of Malagasy hippo:

Actual hippo (not from Madagascar, By Muhammad Mahdi Karim – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=121282994):

A modern hippo skull. There’s a reason the hippo is more dangerous to humans than sharks are [By Raul654 – Darkened version of Image:Hippo skull.jpg, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=242785]:

A pygmy hippo and its calf!

Show transcript:

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

This week we’re going to learn about a topic suggested by the host of the podcast Tracing Owls, because I’m actually a guest on that podcast in an upcoming episode! I think the episode releases later this week. I’ll put a link in the show notes, but be aware that while the podcast is interesting and often very funny, with topics that focus on weird stuff related to science, most episodes are not appropriate for younger listeners. (I think my episode should be okay.)

Several years ago now there was a movie called Madagascar, which is about a group of zoo animals that end up shipwrecked on the island of Madagascar. I love this movie, especially the lemur King Julian, but one of my favorite characters is a hippopotamus named Gloria, voiced by Jada Pinkett Smith. The island country of Madagascar is off the southeastern coast of Africa, but as we talked about in episode 77, it’s been separated from the continent of Africa for millions of years and the animals of that country have mostly evolved separately from the animals of Africa. That’s part of why the movie Madagascar is so funny, since the main characters in the movie are all native to Africa—a lion, a zebra, a giraffe, and Gloria the hippo—and don’t know anything about the animals they encounter on Madagascar. Like this guy:

[King Julian clip]

But it turns out that hippos did once live on Madagascar, and that’s what we’re going to learn about today.

We’re not sure when the first humans visited Madagascar, but it was at least 2500 years ago and possibly as much as 9500 years ago or even earlier. By 1500 years ago people were definitely living on the island. It’s likely that hunting parties would travel to Madagascar and stay there for a while, then return home with lots of food, but eventually people decided it would be a nice place to live.

Madagascar is a really big island, the fourth largest island in the world. It’s been separated from every other landmass for around 88 million years, and has been separated from Africa for about 165 million years. Many of the animals and plants that live on Madagascar are very different from the ones living anywhere else in the world as a result.

To put this into perspective, here’s your reminder that the closest living relative of the hippopotamus is the whale, and 60 million years ago the common ancestor of both hippos and whales was a small semi-aquatic animal. That was about 28 million years after Madagascar was on its own in the big wide ocean, and 105 million years after the landmass that we call Africa broke off from the supercontinent Gondwana and began moving very slowly into the position it’s in today. When Madagascar finally broke free of the landmass we now call India, dinosaurs were still the dominant land animal.

So why are there remains of small hippos on Madagascar? How did the hippos get to Madagascar and why aren’t they still around? Did the hippo originate in Africa or in some other place? So many questions!

The ancestors of modern cetaceans, which includes whales and dolphins and their close relations, are found in the fossil record about 52 million years ago, although it might have been 53 or even 54 million years ago depending on which scientist you ask. That’s when the whale side of the suborder Whippomorpha started developing separately from the hippo side. The “morpha” part of Whippomorpha just means “resembling,” and I’m happy to report that the “whippo” part is actually a combination of the words whale and hippo. Truly, it gave me great joy when I learned this fact, because I assumed “whippo” was something in Greek or Latin, or maybe referred to an animal with a whip-like tail. Nope, whale+hippo=whippo.

Anyway, while we know a fair amount about the evolution of cetaceans from their semi-aquatic ancestors, we don’t know much at all about the hippo’s evolution. There’s still a lot of controversy about whether hippos really are all that closely related to whales after all. They share a lot of similarities both physically and genetically, so they’re definitely relations, but whether they’re close cousins is less certain. The confusion is mainly due to not having enough fossils of hippopotamus ancestors.

The modern hippo, the one we’re familiar with today, usually called the common hippo, first appears in the fossil record about six million years ago. We have fossils of animals that were pretty obviously close relations to the common hippo, if not direct ancestors, that date back about 20 million years. But it’s the gap between the hypothesized shared ancestor of both hippos and cetaceans that lived around 60 million years ago, and the first ancestral hippos 20 million years ago, that is such a mystery.

What we do know, though, is that while the common hippo is native to Africa, its ancestors weren’t. Hippo relations once lived throughout Europe and Asia, and probably migrated to Africa around 35 million years ago. In fact, hippos were common throughout Eurasia until relatively recent times. In 2021, a fossilized hippopotamus tooth was found in a cave in Somerset, England that probably lived only one million years ago. That was well before humans migrated into the area, which was a good thing for the humans because this hippo was humongous. It probably weighed around 3 tons, or 3200 kg, while the common hippo is about half that on average.

This particular huge hippo, Hippopotamus antiquus, lived throughout Europe and only went extinct around 550,000 years ago as far as we know. This was during a time that Europe was a lot warmer than it is today and hippos migrated north from the Mediterranean as far as southern England. The common hippo, H. amphibius, the one still around today, also migrated back into Eurasia during this warm period and its fossilized remains have been found in parts of England too.

These days, there are only two living species of hippo, the common hippo and the pygmy hippo. We talked about the pygmy hippo briefly in episode 135, including the astonishing fact that it only grows around 3 feet tall, or 90 cm, and lives in deep forests in parts of west Africa. There also used to be some other small hippos that evolved on islands and exhibited island dwarfism, and which probably weren’t closely related to the pygmy hippo. These include the Cretan dwarf hippopotamus that lived on the Greek island of Crete until around 300,000 years ago and maybe much more recently, and the Cyprus dwarf hippopotamus that lived on the island of Cyprus until only around 10,000 years ago. The Cyprus hippo was the smallest hippo found so far, only about 2.5 feet tall, or 75 cm. There are dogs larger than that! But the small hippo we’re interested in is the Malagasy pygmy hippopotamus.

There actually wasn’t just one hippo species that lived on Madagascar. Scientists have identified three species, although this may change as more studies take place and as new remains are found. The different species probably didn’t all live on the island at the same time, and some researchers think they might have resulted from three different migrations of hippos to the island.

But how did they get to the island? Madagascar is 250 miles away from Africa, or 400 km, way too far for a hippo to swim. The Malagasy hippos were well established on the island, too, not just a few individuals who accidentally reached shore. That means there must have been some way for hippos to reach Madagascar fairly easily at different times.

The best hypothesis right now is that at times when the ocean was overall shallower than it is now, such as during the Pleistocene glaciations, there are enough small islands between Africa and Madagascar that hippos could travel between them pretty easily. Since those islands would be far underwater now, we don’t have any way to know for sure. We can’t exactly dive down and look for hippo fossils, unfortunately.

The really big question, of course, is whether any hippos still survive on Madagascar. We know they were around as recently as 1,000 years ago, because we have subfossil remains. (Just a reminder that subfossil means that the remains are either not fossilized, or only partially fossilized.) Not only that, the bones show butchering marks so we know people killed and ate the hippos. Right now scientists think the hippos were hunted to extinction by the humans who settled on Madagascar, but there’s some evidence that it happened much more recently than 1,000 years ago.

Over the last several hundred years, European colonizers of Madagascar collected stories from Malagasy natives about animals that resemble hippos. More recently, some stories have also been collected by scientists.

In 1995, a biologist named David Burney, who was studying recently extinct animals on Madagascar, interviewed some elderly residents in various villages. He wasn’t actually trying to learn about mystery animals, he was mostly just trying to find the paleontological sites scientists had found decades before. He figured the older residents would remember those scientists’ visits, and he was right. But the residents also had other stories to tell about the bones dug up by scientists. Some of them said those bones belonged to animals they had seen alive.

In one village, several different people told a story about a cow-sized animal that had occasionally entered the village at night. It was dark in color and made distinctive grunting sounds, and had large floppy ears. When some people approached it too closely, it ran back to the water and submerged.

Dr. Burney thought the residents might have seen pictures of an elephant and transferred some of its details to the mystery animal, especially the large size and floppy ears. But when he showed a picture of an elephant to them, they were clear that it wasn’t the same animal. They chose a picture of a hippo instead, but said the animal they’d seen had larger ears. Various witnesses also said the animal had a large mouth with really big teeth, that its feet were flat, and that it was the size of a cow but didn’t have horns. One man even imitated the animal’s call, which Burney reported sounded like a hippopotamus even though the man had never seen or heard a hippo.

Burney was cautious about publishing his findings, and in fact in his article he mentions that even at the time, he and his team of scientists were cautious about even pursuing information about living Malagasy hippos. They didn’t want to be seen as acting like cryptozoologists, which says a lot about how cryptozoologists conduct their research. Cryptozoology isn’t a scientific field of study despite its name. Biologists, paleontologists, and other experts research mystery animals all the time. That’s just part of their job; they don’t have to call themselves something special. It’s unfortunately common that people who call themselves cryptozoologists don’t have a scientific background and may not know how to conduct proper field research. Very often, cryptozoologists also don’t know very much about the animals that definitely exist, and how can you determine what a true mystery animal is if you don’t know about non-mystery animals?

Luckily, Dr. Burney and his team decided to pursue this particular mystery animal, along with some others they learned about. The last hippo-like animal sighting they could pin to a particular date happened in 1976. If the animal in question was a hippo, and it really was alive only about 50 years ago, it might have gone extinct since then. Or it might still be alive and hiding deep in the forests of Madagascar.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

This is what a hippo sounds like, and you hear it all the time on this podcast because I like it:

[hippo sound]

Episode 306: Two Million Years Ago in Greenland

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This week we’re going to learn about a brand new study in Nature about animals and plants that lived in Greenland about two million years ago.

Happy birthday to Dillon!

Further reading:

A 2-million-year-old ecosystem in Greenland uncovered by environmental DNA

Scientists Reconstruct 2-Million-Year-Old Ecosystem from Environmental DNA

No bones? No problem: DNA left in cave soils can reveal ancient human occupants

Greenland now:

Greenland two million years ago [art by Beth Zaiken, taken from the second article linked above]:

Show transcript:

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

This week we’re going to do something a little different and talk about a new study just published in the journal Nature. A little section of this episode is taken from a recent Patreon episode, for those of you who listen and think, “Wait, I’m pretty sure I’ve heard that before.”

Before we get started, though, we have a birthday shoutout! A great big happy birthday to Dillon! I hope you do something really silly and fun on your birthday, like dance around wearing a ridiculous party hat and then eat cake.

Greenland is a big island off the eastern coast of Canada, but way far north, more or less in the Arctic. Even though it’s off the coast of North America, it’s considered part of Europe because for the last thousand years, it’s been controlled by Norway or Denmark at various times. Denmark’s got it right now. A little over 56,000 people live there today, most of them Inuit.

A big part of Greenland is covered in an ice sheet over a mile thick, which is so heavy it has pushed the central section of the island down so that it’s almost a thousand feet, or over 300 meters, below sea level. The land is much higher around the edges of the country. Basically Greenland is a gigantic bowl full of ice.

In 1966, the U.S. Army drilled into the ice to see what was under it, and the answer is dirt, as you might have expected. They took a 15-foot, or 4.5 meter, core sample and stuck it in a freezer, where everyone promptly forgot about it for 51 years. At some point it ended up in Denmark, where someone noticed it in 2017.

In 2019, the frozen core sample was finally studied by scientists. They expected to find mostly sand and rock. Instead, it was full of beautifully fossilized leaves and other plant material.

The main reason scientists were so surprised to find leaves and soil instead of just rock is that ice is really heavy, and it moves—slowly, but a mile-thick sheet of ice cannot be stopped. If you remember episode 277 about the rewilding of Scotland, you may remember that Scotland doesn’t have a lot of fossils from the Pleistocene because it was covered in glaciers that scoured the soil and everything in it down to bedrock, destroying everything in its path. But this hasn’t happened in Greenland.

Where the ice sheet now is, there used to be a forest. Obviously, the ice sheet hasn’t always covered Greenland. Research is ongoing, but a study of the sediment published in 2021 indicates that Greenland was ice free within the last million years, and possibly as recently as a few hundred thousand years.

If you go back a little farther, around two million years ago, Greenland was radically different. Not only was it ice free, it was much warmer than it is today. In north Greenland, which is now a polar desert, there was once an open forest where an incredible number of plants and animals lived. We know because of environmental DNA sequencing, often referred to as eDNA.

At this point most of us have a good understanding of what DNA is, but I’ll give you a quick explanation in case you’re not sure. DNA stands for Deoxyribonucleic acid, and it’s a polymer chain found in every organism’s cells that contains genetic instructions, essentially a guide on how to grow a particular type of animal. It’s way more complicated than that, but that gives you a basic idea. When cells replicate as an organism develops, either from an egg cell or a seed, the DNA directs what sequences of development happen at what stages. You inherit DNA from your parents but your personal DNA is always a little different from both parents’.

True crime podcasts talk about DNA a lot because every individual organism has a unique DNA profile, and since every single cell in our bodies contains DNA, criminals leave their unique signature at every crime scene. Now that scientists can sequence DNA from really tiny samples, many crimes have been solved when the only evidence was something like “this criminal murdered someone and then smoked a cigarette, and left the cigarette butt, and the DNA from their saliva on the cigarette butt was sequenced and run through a database of criminal DNA profiles, and now we know who the murderer is.” And then you get six commercials for mattresses and phone games.

But animal podcasts talk about DNA a lot because every species of organism has a unique genetic profile in addition to having a unique personal genetic profile. Scientists can retrieve DNA from a poop found in the forest and determine what species of animal left that poop. It probably wasn’t a Bigfoot. Scientists can also compare DNA from different animal populations to learn how closely related they are.

The most recent advance in DNA studies is environmental DNA, and it’s increasing our knowledge of the world in amazing ways. If you look at a lake, even if you go Scuba diving in the lake, even if you send a rover down to look at things in the lake, you won’t be able to see every single animal and plant and other organism that lives there. Fish are always moving around and may swim away from a diver or rover, or the water may be murky, and lots of animals stay hidden in the mud at the lake’s bottom. But if you take samples of the lake water and test it for DNA, suddenly you’re going to have more information than what you’d gather in days or weeks of just looking. Of course it’s important to observe animals in their natural habitats, but if you need to know whether an invasive species is living in the lake, or if an animal that hasn’t been seen for a long time is still extant in the lake, or if there are animals in the lake that no one’s ever seen before, eDNA can do that. The water is full of genetic material shed by different organisms.

It’s not just water, either, although testing water samples is pretty easy. DNA degrades quickly in ordinary circumstances, so while you can test soil to see what animals and plants live nearby, in most cases you’ll only find DNA that was deposited recently. But if the soil has been protected from sunlight, weather, and oxygen, such as soil found in a cave, there’s a chance that some ancient DNA can be found in it. That can tell us a lot about what animals lived in the cave a long time ago.

It’s not a few genetic sequences found in a single sample, either. As one scientist put it, there are trillions of DNA fragments in every single spoonful of dirt. Not all the samples are complete enough to sequence, but the ones that are can tell us a lot about the organisms that encountered that spoonful of dirt when it was at the surface of the cave. In Denisova Cave in Siberia, where a few remains of the Denisovan people were first discovered, researchers have learned that Denisovans and Neandertals lived in the cave for tens of thousands of years at different times, even though there aren’t any bones or artifacts remaining.

But the sediment from the Greenland eDNA study wasn’t from a cave. It had been preserved in permafrost for two million years without anything disturbing it, especially humans. It’s the oldest eDNA that’s been studied so far, more than a million years older than the previously oldest DNA. That was also found in permafrost and was recovered from a mammoth tooth.

Two million years ago in northern Greenland, poplar, birch, and thuja trees grew in an open forest along with various shrubs and other plants like ferns and moss. The thuja is sometimes called the tree of life or arborvitae and it’s an evergreen tree that’s related to junipers, sequoias, and cypresses. A lot of the plant DNA found was a surprise, since pollen from the plants had never been recovered in the area. Lots of plants related to modern roses and azaleas grew in the area, so we know there were flowers in spring and summer.

The area is called Kap København, and while it was still pretty cold, it was warm enough that much of the Greenland ice sheet had melted. In winter the temperature might have sometimes been as warm as 50 degrees Fahrenheit, or 10 Celsius, and only dipped to around 2 degrees Fahrenheit on average, or -17 Celsius. This is a whole lot warmer than modern days, where the winter temperature can drop to -50 Celsius, which is about the same in Fahrenheit, and almost never climbs above freezing except in summer.

Some of the animals that lived in the forest two million years ago were mastodons, reindeer, hares, geese, and various rodents related to voles and lemmings. There was even horseshoe crab DNA found from coastal water that had been pushed farther inland during flooding. All the animals found are related to modern animals that still live today, but only one, the Arctic hare, had actually been found in the fossil record in Greenland. They also found DNA of ants and fleas, plankton, algae, and lots of microbial life.

There is no ecosystem on earth today that quite matches that of Kap København from two million years ago. Until this study, scientists thought that not much lived in the area at the time, certainly not mastodons. Hopefully, environmental DNA can be recovered from even older sediments so we can learn more about the ancient world.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 305: The Chamois and the Cave Goat

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Thanks to Isaac for suggesting the chamois, our main topic this week!

Further reading:

The chamois in New Zealand

Extinct goat was cold-blooded

Myotragus balearicus: Extinction of mouse-goats

A chamois in its summer coat:

A chamois in its winter coat:

Myotragus, the “cave goat,” may have looked something like this museum restoration:

Nuralagus’s femur (left) compared to a regular rabbit femur:

Show Transcript:

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

This week we’re going to talk about an animal suggested by Isaac, the chamois, along with a few other animals. I realize we’ve talked about a lot of mammals lately so I’ll try to switch it up for the last few episodes of the year.

The chamois is a species of what are called goat-antelopes. Its name is French and is spelled c-h-a-m-o-i-s, but in English a lot of people pronounce it “shammy.” Shammy is also what people call polishing cloths of various types, because it’s short for chamois. If you ever heard those commercials on TV for something called the sham-wow, that’s a paper towel thingy that’s based on the shammy cloth. The reason for all this confusion between an animal and a cloth is that the original shammy cloth was a piece of leather from the animal that was used to polish high-quality items like fancy cars since it’s very soft and won’t scratch anything. Most shammy cloths you buy these days are likely to be made from plush cloth or the skin of domestic goats or sheep.

As for the animal, it’s native to mountainous parts of Europe, including the Alps. It’s also been introduced to New Zealand’s South Island where it’s an invasive species that threatens many native plants. Since chamois meat is considered a delicacy, commercial hunters in New Zealand travel into the mountains by helicopter, kill as many of the animals as possible, and bring the meat back to sell to restaurants. This is encouraged by the New Zealand government in an attempt to protect native plants, although red deer, feral goats, and hares are also introduced animals that do a lot of damage to the delicate mountain environment.

The chamois is small, only about two and a half feet tall at the shoulder, or 80 cm. It has cloven hooves and both males and females have small black horns. The horns are mostly straight but bend backwards at the tips into a sort of hook shape, and while males have thicker horns, they aren’t usually that much longer than the female’s. Horns grow up to 11 inches long, or 28 cm.

In summer the chamois’s fur is light brown with a darker stripe on each side of the face that runs from the nostrils, over the eyes, and up to the horns. In winter its fur grows very thick to keep it warm in its mountainous habitat, and it’s a much darker brown, almost black. It still has the dark band on its face with lighter colored fur on its cheeks and jaw, though. Its tail is very short and isn’t usually visible.

Female chamois live in small groups along with their offspring. Males are solitary most of the year, but during mating season in autumn and early winter, called the rut, males fight each other for the attention of females. The female gives birth to a single kid in late spring. In the winter the chamois migrates to lower elevations where there’s more food, but in summer it migrates to high elevations above the treeline where it’s safer from predators. It can run extremely fast, up to about 30 miles per hour, or 50 km/hour, and can jump as much as 20 feet, or 6 meters. It can even jump over six and a half feet high, or 2 meters, straight up. It’s very bouncy.

I mentioned that the chamois is a goat-antelope, so let’s go back to that term. The goat-antelope isn’t actually a type of antelope, although it is an antelope relation. Goat-antelopes are bovids, along with antelopes, actual goats, sheep, cows, and many others. The goat-antelopes are members of the subfamily Caprinae, which includes goats, sheep, musk ox, mountain goats, takins, and many other interesting animals that we need to talk about one day. One of these is the extinct Myotragus, called the mouse goat or the Balearic Islands cave goat because the first fossils were found in a cave. It didn’t actually live in caves, although it was weird in other ways.

The cave goat was a small animal, only about 18 inches tall, or 46 cm, and both males and females had small horns that probably looked like a goat’s horns. Like most other goat-antelopes, researchers think the cave goat was a browser that ate lots of different kinds of plants, although its ancestors had probably been grazers that ate mostly grass. But its eyes were oriented for binocular vision like a predator’s eyes, instead of being on the sides of its head as in most herbivores, which allows an animal a much wider range of vision to watch for predators. Since the cave goat had lived on islands for several million years and didn’t need to worry about large predators, it didn’t need the adaptations that other prey animals have. For instance, it probably was a slow walker and couldn’t jump at all, sort of the opposite of the chamois.

An analysis of the rate of growth in the cave goat’s bones discovered something really weird. Most mammals grow quickly and steadily throughout their youth and then stop growing when they reach adulthood. The cave goat grew very slowly and sometimes stopped growing completely for a while, and didn’t reach full maturity where growth stopped until it was about 12 years old. Most goat-antelope species reach their full size within a year or two. This pattern resembles that of a reptile, not a mammal, and researchers think it was an adaptation to its restricted habitat. An island only has so much food available at any given time, so being able to slow or stop growing for a while when food is scarce, then resume growing when there’s more food to convert to energy, is an efficient way to deal with scarcity. When the finding was published in 2009, a lot of articles called the cave goat cold-blooded, or ectothermic, but we don’t actually know if this was the case.

The cave goat went extinct around 3,000 years ago when humans arrived on the islands where it lived. But instead of ending on that sad note, let’s look very quickly at another animal that lived on the same islands before the cave goat. It was a gigantic weird rabbit called Nuralagus rex.

Nuralagus was a rabbit but due to island gigantism, it was way larger than an ordinary rabbit and would have looked very different. It was about 20 inches tall at the highest point of its back, or 50 cm. Like the cave goat but unlike other rabbits, it couldn’t jump. Its spine was stiff and there weren’t very many predators to worry about, so it could just walk around and find plants and other giant bunnies and that’s all it needed. It didn’t have very good hearing compared to most rabbits, so its ears were probably much shorter in relation to its body. It was only described in 2011, which just goes to show how many weird animal discoveries are still waiting to be found.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 304: Animals of the Paleogene

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Thanks to Pranav for suggesting this week’s topic, animals of the Paleogene, the period after the Cretaceous! Thanks also to Llewelly for suggesting the horned screamer, now one of my favorite birds.

Further watching:

Southern Screamers making noise

Horned Screamers making noise

Further reading:

The Brontotheres

Presbyornis looked a lot like a long-legged goose [art by Smokeybjb – CC BY-SA 3.0]

The southern screamer (left) and horned screamer (right), probably the closest living relation to Presbyornis:

Megacerops was really really big:

All four of these illustrated animals are actually megacerops, showing the variation across individuals of nose horn size:

Uintatherium had a really weird skull and big fangs:

Pezosiren didn’t look much like its dugong and manatee descendants:

Show transcript:

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

This week we’re going to look at some strange animals of the Paleogene period, a suggestion from Pranav. Pranav also suggested the naked mole-rat that we talked about in episode 301, but I forgot to credit him in that one.

As we talked about in episode 240, about 66 and a half million years ago, a massive asteroid smashed into the earth and caused an extinction event that ended the era of the dinosaurs. The geologic time period immediately after that event is called the Paleogene, and paleontologists study this era to learn how life rebounded after the extinction event. We’re going to learn about a few animals that evolved to fill ecological niches left vacant after dinosaurs went extinct.

These days, mammals fill a whole lot of these ecological niches, so it’s easy to assume that mammals have been successful for the last 66 million years. But while that’s true now, birds were incredibly successful for a long time. Basically for millions of years after the non-avian dinosaurs died out, it was dinosaurs 2.0 as the avian dinosaurs, better known as birds, spread throughout the world and evolved into some amazing organisms.

This included terror birds, which we talked about in episode 202. They lived in South America, except for one species from North America, and evolved really soon after the dinosaurs went extinct, appearing in the fossil record about 60 million years ago. They lasted a long time, too, only going extinct around 2 million years ago.

The earliest known terror bird was about three feet tall, or 91 cm, but its descendants became larger and more fearsome until they were apex predators throughout South America. The biggest species grew up to ten feet tall, or three meters, with a massive beak and sharp claws on its toes. It couldn’t fly but was a fast runner. You would not want a terror bird chasing you.

Lots of other birds evolved throughout the Paleogene, but most of them would look pretty familiar to us today. Paleontologists have found fossils of the ancestors of many modern birds, including penguins, hummingbirds, and parrots, which shows that they were already specialized some 25 or 35 million years ago or even more. In the case of penguins, we have fossils of penguin ancestors dating back to the late Cretaceous, before the extinction event. Those ancient penguins could probably still fly, but it didn’t take too long to evolve to be a fully aquatic bird. The species Waimanu manneringi lived around 62 million years ago in what is now New Zealand. It resembled a loon in a lot of ways, with its legs set well back on its body, and it probably spent much of its time floating on the water between dives. But unlike a loon, it had lost the ability to fly and its wings were already well adapted to act as flippers underwater.

Another bird would have looked familiar at first glance, but really weird when you gave it a second look. Presbyornis lived between about 62 and 55 million years ago in what is now North America, and it lived in flocks around shallow lakes. It was the size of a swan or goose and mostly shaped like a goose, with a fairly chonky body and a long neck. It had a large, broad duckbill that it used to filter small animals and plant material from the water and its feet were webbed…but its legs were really long, more like a heron’s legs.

When the first Presbyornis fossils were found in the 1920s, the scientists thought they’d found ancient flamingos. But when a skull turned up, Presbyornis was classified with ducks and geese. It wasn’t very closely related to modern ducks and geese, though. Researchers now think its closest modern relation is a South American bird called the screamer. Llewelly suggested the horned screamer a long time ago and now that I have learned more about these birds, I love them so much!

The screamer looks sort of like a goose but has long, strong legs and a sharp bill more like a chicken’s. It lives in marshy areas and eats pretty much anything, although it prefers plant material. It has two curved spurs that grow on its wings that it uses to defend its territory from predators or other screamers, and if a spur breaks off, which it does pretty often, it grows back. The screamer mates for life and both parents build the nest together and help take care of the eggs and chicks when they hatch.

The horned screamer has a long, thin structure that grows from its forehead and looks sort of like a horn, although it’s not a horn. It’s wobbly, for one thing, but it’s also not a wattle. It grows throughout the bird’s life and may break off at the end every so often, and it’s basically unlike anything seen in any other bird. Maybe presbyornis had something similar, who knows?

The screamer gets its name from its habit of screaming if it feels threatened or if it just encounters something new or that it doesn’t like. The screaming is actually more of a honking call that sounds like this:

[screamer call]

People sometimes raise screamers with chickens to act as guard birds. It can run fast but it can swim faster, and it can also fly although it doesn’t do so very often. Although it’s distantly related to ducks, its meat is spongy and full of air sacs that help keep it afloat in the water, so people don’t eat it. It is vulnerable to habitat loss, though.

One organism that evolved early in the Paleogene was grass. You know, the plant that a whole lot of animals eat. There are lots and lots of different types of grass, not just the kind we’re used to mowing, and as the Paleogene progressed, it became more and more widespread. But it wasn’t as ubiquitous as it is now, so even though the ancestors of modern grazing animals evolved around the same time, they weren’t grazers yet. The word graze comes from the word grass, but ancient ancestors of horses and other grazing animals were still browsers. They ate all kinds of plants, and didn’t specialize as grazers until grasses really took off and huge grasslands developed in many parts of the world, around 34 million years ago.

Because the Paleogene lasted so long, between about 66 and 23 million years ago, there’s literally no way we can talk about more than a few animals that lived during that time, not in a single 15-minute episode. We’ve also covered a lot of Paleogene animals in previous episodes, like paraceratherium in episode 50, the largest land mammal known. It probably grew up to about 16 feet tall at the shoulder, or 5 meters, and taller if you measured it at the top of its head. Other examples are moeritherium, an ancient elephant relation we talked about in episode 18, the giant ground sloth that we talked about in episode 22, and the ancient whale relation basilosaurus that we talked about in episode 132. Patrons also got a bonus basilosaurid episode this month. But I’m pretty sure we’ve never talked about brontotheres.

Brontotheres first appear in the fossil record around 56 million years ago and they lived until at least 34 million years ago. All animals in the family Brontotheriidae are extinct, but they were closely related to horses. They didn’t look like horses, though; they looked a lot like weird rhinoceroses, although remember that rhinos are also related to horses. They were members of the odd-toed ungulates, along with tapirs and the gigantic Paraceratherium.

Fossil remains of brontotheres have been found in North America, a few parts of eastern Europe, and Asia, although they might have been even more widespread. The earliest species were only about three and a half feet tall at the shoulder, or about a meter, but later species were much larger. While they looked a lot like rhinos, they didn’t have the kind of keratin hose horns that rhinos have. Instead, some species had a pair of horns made of bone that varied in shape and size depending on species. The horns were on the nose as in rhinos, but were side-by-side.

Brontotheres developed before grasslands became widespread, and instead they were browsers that mostly ate relatively soft vegetation like leaves and fruit. Grass is really tough and animals had to evolve specifically to be able to chew and digest it. In fact, the rise of grasslands as the climate became overall much drier around 34 million years ago is probably what drove the brontotheres to extinction. They lived in semi-tropical forests and probably occupied the same ecological niche that elephants do today. This was before elephants and their relations had evolved to be really big, and brontotheres were the biggest browsing animals of their time.

Brontotheres probably lived in herds or groups of some kind. They were widespread and common enough that they left lots of fossils, so many that they were found relatively often in North America even before people knew what fossils were. The Sioux Nation people were familiar with the bones and called them thunder horses. When they were scientifically described in 1873 by Othniel Marsh, he named them after the Sioux term, since brontotherium means “thunder beast.”

Two of the biggest brontotheres lived at about the same time as each other, around 37 to 34 million years ago. Megacerops lived in North America while Embolotherium lived in Asia, specifically in what is now Mongolia. Megacerops is the same animal that’s sometimes called brontotherium or titanotherium in older articles and books.

Megacerops and Embolotherium were about the same size, and they were huge, although Embolotherium was probably just a bit larger than Megacerops. They stood over 8 feet tall at the shoulder, or 2.5 meters, and were more than 15 feet long, or 4.6 meters. This is much larger than any rhinos alive today and as big as some elephants. Their legs would probably have looked more like an elephant’s legs than a rhinoceros’s.

Brontothere nose horns weren’t true horns, since they don’t seem to have been covered with a keratin sheath, but they were formed from protrusions of the nasal bones. They might have been more like ossicones, covered with skin and hair. Megacerops had a pair of nose horns that were much larger in some individuals than others, and scientists hypothesize that males had the larger horns and used them to fight each other.

But this can’t have been the case for embolotherium. It had even bigger nose horns that were fused together in a wedge-shaped plate sometimes referred to as a ram, but they contained empty chambers inside that were a continuation of the nasal cavities. They wouldn’t have been strong enough to bash other embolotheriums with, but they might have acted as resonating chambers, allowing embolotherium to communicate with loud sounds. All individuals had these nose horns, even juveniles, and they were all about the same size, which further suggests that they had a purpose unrelated to fighting.

At about the same time the brontotheres were evolving, another big browsing animal also lived in what are now China and the United States. Two species are known, one in each country, and both stood about 5 feet tall at the shoulder, or 1.5 meters. It looked sort of like a brontothere in some ways, but very different in other ways, especially its weird skull, and anyway it was already big around 56 million years ago when brontotheres were still small and unspecialized.

Scientists aren’t sure what uintatherium was related to. It’s been placed in its own genus, family, and order, although some other uintatherium relations have been discovered that share its weird traits. Most scientists these days think it was probably an ungulate.

Uintatherium’s skull was extremely strong and thick, which didn’t leave a whole lot of room for brains. But what uintatherium lacked in brainpower, it made up for in sheer defensive ability. It had huge canine teeth that hung down like a sabertooth cat’s fangs, although males had larger fangs than females. Males also had three pairs of ossicones or horns on the top of the skull that pointed upwards. One pair was on the nose, one pair over the eyes, and one pair almost on the back of the skull. They could be as much as 10 inches long, or 25 cm, and paleontologists think that males wrestled with these horns the same way male deer will lock antlers and wrestle.

Uintatherium lived in the same habitat and probably ate more or less the same type of plants that later brontotheres did. They went extinct around the time that brontotheres evolved to be much larger, which suggests that brontotheres may have outcompeted uintatherium.

We’ll finish with one more Paleogene mammal, Pezosiren. It was only described in 2001 from several incomplete specimens discovered in Jamaica in the 1990s, and it lived between 49 and 46 million years ago.

Pezosiren was about the size of a pig, although it had a longer, thicker tail compared to pigs. It wasn’t any kind of pig, though, and in fact it was distantly related to elephants. It was the oldest known ancestor of modern sirenians. Pezosiren is also called the walking siren, because it still had four legs and probably spent at least part of the time on land, although it could swim well. Scientists think it probably swam more like an otter than a sirenian, propelling itself through the water with its hind legs instead of its tail.

Pezosiren was probably semi-aquatic, sort of like modern hippos, and already shows some details specific to sirenians, especially its heavy ribs that would help it stay submerged when it wanted to. It ate water plants and probably stayed in shallow coastal water. At different times in the past, Jamaica was connected to the North American mainland or was an island on its own as it is now, or occasionally it was completely submerged. About 46 million years ago it submerged as sea levels rose, and that was the end of Pezosiren as far as we know. But obviously Pezosiren either survived in other areas or had already given rise to an even more aquatic sirenian ancestor, because while Pezosiren is the only sirenian known that could walk, its descendants were well adapted to the water. They survive today as dugongs and manatees.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!