Episode 026: Humans Part Two

Part two of our humans episode is about a couple of our more distant cousins, the Flores little people (Homo floresiensis) and Homo naledi, with side trips to think about Rumpelstiltskin, trolls, and the Ebu gogo.

Homo floresiensis skull compared to a human skull. We are bigheaded monsters in comparison. Also, we got chins.

Homo naledi’s skull. I stole that picture from Wits University homepage because I really liked the quote and it turns out it’s too small really to read. Oh well.

Some of our cousins. Homo erectus in the middle is our direct ancestor. So is Lucy, an Australopithecus, although she lived much longer ago.

Show transcript

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

This week is part two of our humans episode. Last week we learned how modern humans evolved and about two of our close cousins, Neandertals and Denisovans. This week, we’re going to walk on the weirder side of the hominin world.

Before we get started, this episode should go live on July 31, 2017, one week before I fly to Helsinki, Finland for WorldCon 75! Don’t worry, I’ve got episodes scheduled to run normally until I get home. If you’re going to be in Finland between August 8 and August 17, let me know so we can meet up. On Thursday, August 10 and 4pm I’ll be on a panel in room 207 about how to start a podcast, so check it out if you’re attending the convention. I’ll also be in Oslo during the day on August 7 and have two birding trips planned with lunch in between, and I’d love you to join me if you’re in Oslo that day too. Then, two weeks after I return from Finland, I’ll be attending DragonCon over Labor Day weekend. blah blah blah this is old news

Now, let’s learn about some of our stranger distant cousins!

In 2003, a team of archaeologists, some from Australia and some from Indonesia, were in Indonesia to look for evidence of prehistoric human settlement. They were hoping to learn more about when humans first migrated from Asia to Australia. One of the places they searched was Liang Bua cave on the island of Flores. They found hominin remains all right, but they were odd.

The first skeleton they discovered was remarkably small, only a bit more than three and a half feet tall [106 cm] although it wasn’t a child’s skeleton. That skeleton was mostly complete, including the skull, and appears to be that of a woman around 30 years old. She’s been nicknamed the Little Lady of Flores, or just Flo to her friends. Officially, she’s LB1, the type specimen for a new species of hominin, Homo floresiensis.

But until very recently, that statement was super controversial. In fact, there’s hardly anything about the Flores remains that aren’t controversial.

At first researchers thought the remains were not very old, maybe only twelve or thirteen thousand years old, or 18,000 at the most. Stone tools were found in the same sediment layer where Flo was discovered, as were animal bones. The tools were small, clearly intended for hands about the size of Flo’s, which argued right off the bat that she was part of a small-statured species and wasn’t an aberrant individual.

The following year, 2004, the team returned to the cave and found more skeletal remains, none very complete, but they were all about Flo’s size. Researchers theorized that the people had evolved from a population of Homo erectus that had arrived on the island more than three quarters of a million years before, and that they had become smaller as a type of island dwarfism. A volcanic eruption 12,000 before had likely killed them all off, along with the pygmy elephants they hunted.

But as more research was conducted, the date of the skeletons kept getting pushed back: from 18,000 years old to 95,000 years old to 150,000 years old to 190,000 years old. Dating remains in the cave is difficult, because it’s been subject to flooding and partial flooding over the centuries. Currently, the skeletal remains are thought to date to 60,000 years ago and the stone tools to around 50,000 years ago.

When news of the finds was released, the press response was enthusiastic, to say the least. The skeletons were dubbed Hobbits for their small size, which made the Tolkien estate’s head explode, and practically every few weeks it seems there was another article about whether there were small people still living quietly on the island of Flores, yet to be discovered.

And, of course, there were lots of indignant scientists who were apparently personally angry that the skeletons were considered a new species of hominin instead of regular old Homo sapiens. Part of the issue was that only one skull has ever been found. It’s definitely small, and the other skeletal remains are all correspondingly small, and the stone tools are all correspondingly small, and the skull shows a number of important differences from that of a normal human. But that doesn’t necessarily mean it’s not a subspecies of Homo sapiens, and of course that needs to be investigated. But some of the arguments got surprisingly ugly. There were even accusations that the entire find was faked. One person even suggested that the skull’s teeth showed evidence of modern dental work.

Amid all this, two unfortunate things happened. First, in December 2004 an Indonesian paleoanthropologist named Teuku Jacob removed almost all the bones from Jakarta’s National Research Centre of Archaeology for his own personal study for three months. When he returned them, two leg bones were missing, two jaw bones were badly damaged, and a pelvis was smashed. Then, not long after, Indonesia closed access to Liang Bua cave without explanation, although the archeological community suspected it was due to Jacob’s influence, and didn’t reopen it until 2007 after Jacob died.

It’s important to note that Jacob was a proponent of the theory that the remains found in Liang Bua cave were microcephalic individuals of the prehistoric local population, not a new hominin species at all. He also had a history of keeping Indonesian fossils from being studied unless he specifically approved of the research.

At any rate, since then, repeated studies of the LB1 skull have suggested that Homo floresiensis is a separate species of hominin and not a Homo sapiens with evidence of pathology, whether microcephaly or another disease, or a population with a genetic abnormality. There’s still plenty of research needed, of course, and hopefully some more skulls will be found. But it seems clear that Homo floresiensis isn’t just a weird subspecies of Homo sapiens.

One of the more common theories in the last few years was that Homo floresiensis was descended from Homo erectus, although Homo erectus was a lot bigger and more human-like than the Flores little people. But results of a study released just a few months ago show that Homo floresiensis shared a common ancestor with Homo habilis around 1.75 million years ago. Homo floresiensis may have evolved before migrating out of Africa, or their ancestor migrated and evolved into Homo floresiensis. Either way, they spread as far as Indonesia before dying out around 50,000 years ago.

Other hominin remains have since been found on the island. Part of a jaw and teeth were found at Mata Menge on the island of Flores, some 50 miles away from the cave. It’s around 700,000 years old and is a bit smaller than the same bones in the later skeletons. Researchers think it’s an older form of Homo floresiensis.

Possibly not coincidentally, modern humans arrived on the island about 50,000 years ago, maybe earlier, bringing with them the arts of fire, painting, making jewelry from animal bones, and killing all of our genetic cousins.

We don’t know if humans deliberately killed the Homo floresiensis people or if they just outcompeted them. It does seem pretty certain that the two hominin species coexisted on the island for at least a while. It’s even possible that knowledge of the strange small people of the island has persisted in folk tales told by the Nage people of Flores. Stories about the ebu gogo have been documented for centuries. They were supposed to be little hairy people around three feet tall [one meter], with broad faces and big mouths. They were fast runners with their own language and would eat anything, frequently swallowing it whole. In some stories they sometimes kidnapped human children to make the children teach them how to cook, although the children always outwitted the ebu gogo.

Supposedly, at some point, tired of their children being kidnapped and their food being stolen, villagers gave the ebu gogo palm fibers so they could make clothes. The ebu gogo took the fibers to their cave, and the villagers threw a torch in after them. The fiber went up in flames and killed all of the ebu gogo.

Until the discovery of Homo floresiensis, anthropologists assumed the stories were about macaque monkeys. But there’s a genuine possibility that the ebu gogo tales are memories of Homo floresiensis. It’s not just cryptozoologists and bigfoot enthusiasts making the connection between the ebu gogo and Homo floresiensis. Articles and editorials have appeared in journals such as Nature, Scientific American, and Anthropology Today. At least, they did back when archeologists thought Flo was only about 12,000 years old.

But we still don’t know for certain when Homo floresiensis went extinct. There may be remains that are much more recent than 50,000 years ago. Locals mostly say there are no ebu gogo left but that they were still around about a century ago. I don’t know how long historical elements can persist in an oral tradition without becoming distorted. As we discussed in episode 17, about Thunderbird, oral history is easily lost if the culture is disrupted by invasion, disease, war, or other major episodes. But some stories are tougher than others, and those that are less history and more entertainment—although they may contain warnings too—can be very, very old.

Researchers have traced some traditional folktales, like Rumpelstiltskin, back some 4,000 or even 6,000 years, although not without controversy. But while Rumpelstiltskin is usually described as a small person, no one’s suggesting that story is about real events. It’s the juxtaposition of the Flores discoveries of small skeletons and the oral tradition or small people living on the island that got researchers excited. And as it happens, there is an oral tradition many miles and many cultures away from Flores that might be something similar.

Old Norse stories about trolls date back thousands of years. The trolls vary in appearance and sometimes have a lot of overlap with other monsters, but generally are described as big and strong, not very smart, often placid unless provoked, and usually evil, or at least godless. Sometimes they capture humans who outwit them to escape. In one story, a man named Esbern Snare wanted to marry a woman, but her father would only agree to the marriage if Esbern would build a church. Esbern struck a deal with a troll, who said he would build the church—on one condition. If Esbern couldn’t guess the troll’s name by the time the church was built, the troll would demand as his payment Esbern’s heart and eyes.

Esbern agreed, but he failed to trick the troll into telling him his name. On the final day, in despair Esbern threw himself down on the bank of a river, where he overheard the troll’s wife singing to her baby:

“Hush, hush, baby mine,

Tomorrow comes Finn, father thine,

To bring you Esbern’s heart and eyes

To play with, so now hush your cries.”

Esbern rushed back to the church and greeted Finn the troll by name. In some version of the story, Finn is so furious that he leaves the church incomplete in some way, usually a missing pillar. For those of you who aren’t familiar with the Rumpelstiltskin story, that’s a variant. Oh, and Esbern Snare was a real person who lived in the twelfth century, although I’m pretty sure he didn’t actually strike any deals with trolls.

But I do wonder if some elements of troll folklore might be derived from memories of Neandertal people. I’m not the first to suggest this, although it is a pretty fringey theory. And in the end, we just don’t have any way to know. But it is interesting to think about.

As you may remember from part one of the humans episode, Homo sapiens evolved roughly 200,000 years ago. But around the same time, or a little earlier, another cousin in our family tree was living in southern Africa. Remains of Homo naledi were only discovered in 2013 by some cavers. Partial skeletons from at least 15 individuals were recovered in one field season, but due to narrow cave passages, the field work had to be done by people of small stature who weren’t claustrophobic, mostly women.

Homo naledi is a mixture of primitive and advanced features. Primitive in this case means more like our ape ancestors, and advanced means more like modern humans. Homo naledi had long legs and feet that looked just like ours, but also had a small brain and fingers that are much more curved than ours—not characteristics that would look out of place a few million years ago, but surprising to discover in our family tree at about the same time that modern humans were evolving.

On the other hand (with curved fingers), evolution doesn’t have an end goal. Homo sapiens is not the pinnacle of creation to which all other living beings aspire. We’re just another animal, just another great ape. If Homo naledi was successful in their environment with a small brain, that’s all that matters from an evolutionary standpoint.

There are lots of remains left in the cave, so many in fact that some researchers are convinced they didn’t get there by accident. It’s possible that the cave was used as a burial pit, maybe even over the course of centuries. Bodies may have been dropped in a deep shaft and were then moved by periodic flooding to the remote chamber where they were found, or they may have been carried to the cave depths and left there.

Homo naledi wasn’t a direct ancestor of Homo sapiens, but they were definitely a kind of human—no matter how small their brains may have been.

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 025: Humans Part I (Neanderthals and Denisovans)

This week is our first two-parter ever! I don’t intend to do that often but there was just too much to go over for one episode. This week we’ll talk about humans: where we come from, how we evolved, and who our closest cousins are–Neanderthals and Denisovans.

Some young humans. Humans can do many surprising things, including surfing, making stained glass, and repairing helicopters. Most humans like the color blue and enjoy listening to music.

The bracelet found with Denisovan bones in a Siberian cave. Humans didn’t make or wear this lovely thing, Denisovan people did.

Further reading:

How to Think Like a Neandertal by Thomas Wynn and Frederick L. Coolidge

Show transcript:

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

This will be our first two-part episode. There’s so much to cover with this topic that I decided to split it into two. This week we’re going to investigate an unusual family of great apes: both the living representative and their extinct relatives—and I don’t know why I’m saying “their extinct relatives,” because the great apes in question are known as Homo sapiens.

Humans tend to view ourselves as separate from the natural world. Some of us see ourselves as special, above other animals and better than them. Some of us see ourselves as despoilers of nature who can’t be trusted at all. But in reality, we’re neither angels nor devils. We’re animals too, and we fit neatly in the world because we evolved to live here, just like every other animal did too.

Humans have two major things going for us. First of all, we’re really smart. We’re only now learning the ways other animals show high intelligence, but even so, hands down we are the brightest apes in the circus. Our intelligence allows us to invent amazing things to make our lives more comfortable, like beds and shoes and medicine and umbrellas and podcasts. Unfortunately, our intelligence also lets us invent things that aren’t so nice, like bombs, because like our close cousins the chimpanzees, we can be real jerks.

But besides our intelligence, which is an obvious plus, we’ve got something very few other animals have: stamina, and the ability to shed heat efficiently, which makes us tireless hunters. In fact, that combined with our ability to make and use tools made early humans pretty much unstoppable.

Persistence hunting is only practiced by a few species of animal, like grey wolves, spotted hyenas, and humans. Humans aren’t especially fast runners compared to horses and deer and other prey animals, but we can just run on and on, sweating to cool ourselves, while our prey has to rest to cool down. One downside to this is that we can drive ourselves to heat exhaustion without realizing it, when conditions are just too hot to be constantly active.

I just looked this up, because I just realized I didn’t know if other female animals menstruate like human women. It turns out that female chimps do, along with a few other primates—and bats, for some reason. Solidarity with our bat girlfriends.

Actually, all placental mammals prepare a womb lining periodically, but when it turns out they don’t need it because they’re not going to have babies, they just reabsorb the material. Only a few species shed it, and even in humans we reabsorb most of it. Some researchers think we menstruate because it’s actually easier on the body to just dump the last of that unused stuff rather than spend extra energy absorbing it.

Now that we all know a few things about humans that we might not have known before, here’s a somewhat simplified overview of how humans evolved.

Humans and our ancestors are called hominins collectively. There were some apes 6 or 7 million years ago that were probably somewhat bipedal, and which are considered the earliest known hominins. We’re not sure which of the several species is our direct ancestor and which is our last shared ancestor with gorillas and chimpanzees.

Bipedalism is a defining trait of hominins. It took a long time to develop because there are a lot of skeletal and other changes needed to make it work effectively. By about 3 or 4 million years ago, the Australopithecines had evolved, and we know they walked upright at least part of the time because we have a fossilized track.

But why did bipedalism develop in the apes at all? Of all the apes, only humans developed bipedalism, and it actually still gives us a lot of problems: weak backs that are subject to injury, for instance, and even increased difficulty in childbirth, since the human pelvis had to change so much to adapt to walking upright. The cause was probably habitat change.

If you look at a map of Africa, you’ll see what looks like a string of lakes on the eastern side of the continent. Those lakes, and the volcanoes scattered around the area, including Mount Kilimanjaro, are caused by the East African Rift. Researchers are still working out what exactly is causing the rift, but we do know what’s happening in general. The tectonic plate Africa sits on, which is naturally known as the African Plate, is splitting in two.

This sounds alarming, especially if you happen to live there, but it’s a ridiculously slow process from our point of view. The rift widens barely seven millimeters a year. But that adds up when you’re talking millions of years, and the rift started at least ten million years ago and will continue for another ten million years until the plates separate completely and those lakes become part of the ocean.

Around the time the rift started forming, the East African plateau rose up, accompanied by a lot of volcanic activity. This caused a major change in the local habitats. What had once been thick forest and lush jungle became open woodland and savanna. Grasses grew tall, there wasn’t as much cover, and the animals that evolved and moved into the area were fast runners. It wasn’t a great area to be a knuckle-walker like other apes, but it was ideal for apes who could stand and walk upright.

The rift is where we’ve found so many important hominin fossils, including that of Lucy. Lucy was an Australopithecus who lived 3.2 million years ago. In Ethiopia, where the partial skeleton was found, she’s known as Dinknesh, which means “you are marvelous” in the local language.

That kind of makes me want to cry a little. Lucy wasn’t just some ape who could walk upright part of the time while carrying things. She was our great-great-great-a million times-great grandma.

[oops copyright infringement hahahahahahahahahahaha]

By around two and a half million years ago, Homo habilis had evolved. Homo habilis probably still looked a lot like an ape, but was also getting recognizably human. They walked upright all the time and made stone tools. Then, a little less than two million years ago, Homo erectus appears in the fossil record.

Homo erectus was definitely human-looking, with a human-like nose, ordinary human-sized height, and very little hair except on the head. And Homo erectus had dark skin, which is linked to the loss of body hair.

By a little less than one million years ago, Homo erectus was wearing clothes, cooking their food, and were adept in making and using stone tools. If you went back in time and met a Homo erectus, you’d think you were just meeting a really weird-looking person—and you would be right. Also, where did you get the time machine and can I get a ride in it?

By 200,000 years ago, modern humans, Homo sapiens, had fully evolved. If you could go back in time and meet those early humans, they would look, act, and think like the people you see around you today.

Of course, evolution isn’t as cut and dried as it sounds here. When one species evolves over long, slow generations into another, that doesn’t mean the population it evolved from vanishes. You may have heard the so-called argument against evolution: if humans evolved from monkeys, why are there still monkeys?

Well, first of all, apes and monkeys are different animals entirely. Both monkeys and apes, and all the other primates, evolved from a distant ancestor that wasn’t a monkey or an ape, but which had the characteristics that made it distinctly primate instead of feline or canine or hippopotamine…that’s not a word.

Second of all, species evolve because of environmental pressures, and those same pressures may not be present in all parts of the species’s range. Homo erectus survived well into the era of modern humans, and in fact we probably killed them off, either directly (because remember, we can be jerks) or indirectly by outcompeting them in the same habitats.

At some point, humans started moving out of Africa into other parts of the world, maybe about 55,000 years ago although we’re not really sure yet. Researchers are still working it all out, but some research suggests there might be more than one wave of migration, or that the migration started much earlier than 55,000 years ago.

The hominins I’ve mentioned so far weren’t the only ones around. Those were only our direct ancestors. There were others who split off from our ancestors and evolved separately, and if they hadn’t all died out (again, thanks to us, Homo sapiens jerkuses), we’d have populations of living cousins who are much more closely related to us than the other great apes. So let’s learn about some of them!

I’ve actually been putting off doing this episode because right now, we’re in the middle of a golden age of hominin discoveries. I kept thinking that if I just waited a few more weeks or months, new findings might very well be announced. In fact, right after I started research, sure enough, new information was published about a recently discovered Denisovan baby tooth.

There are two known groups of hominins who aren’t direct human ancestors to Homo sapiens, Neanderthals and Denisovans. They were around at the same time as modern humans for at least a while, but not usually in the same places.

Neanderthals spread throughout parts of northern Europe and Asia, and the Denisovans spread into Asia and down through the Malay Archipelago and into Australia. Again, I need to stress that these were not direct human ancestors. While they could and did interbreed with Homo sapiens, and many modern populations carry traces of Neanderthal and Denisovan DNA, there is no practical genetic difference in a human from one continent or background and a human from a different continent or background. We’re all human.

Around 1.8 million years ago, a population of Homo erectus migrated into Eurasia, where they gave rise to Neanderthals and Denisovans. When humans later migrated into the same areas, they encountered their close cousins and lived alongside them for possibly as long as 10,000 years before the human population increased to the point that…those other guys? They had to go.

The first Neanderthal fossils were discovered in 1829 in Belgium, but it’s the 1856 discovery of fossils in a cave in Neader Valley in Germany that gave us their name. “Thal” [pronounced like the word tall] means dale or valley in German, spelled with a TH, which is why so often the name is pronounced Neander-thal. It doesn’t really matter how you pronounce it.

Anyway, there’s still a lot of controversy regarding whether Neanderthals are a subspecies of Homo sapiens or a separate species in their own right. One incredibly “clever” and just precious suggestion in 1866 was that the group be named Homo stupidus. In fact, Neanderthals were probably as smart as humans and were definitely bigger and stronger than us (so don’t make jokes about them). They were well adapted to the cold with a barrel chest, relatively shorter limbs than humans, and an overall more robust build. They probably had better eyesight than we do too. Genetic evidence suggests that some populations may have had light skin and red or blond hair.

But it’s possible they weren’t as socially adept as humans. The average Neanderthal social group consisted of a close family unit—mother, father, and kids, or brothers and their mates, who were not related to one another, plus their kids—rather than extended relatives and related families, as is typical among humans. It’s likely that several family groups sometimes came together to share particular bonanzas in food. Neanderthals frequently killed mammoths, and a full-grown mammoth could feed a whole lot more than one family before the meat spoiled.

Grandparents probably weren’t usually part of most family groups not because no one liked their Grandma back then, but because Neanderthals had short, brutal lives. They speared mammoths at close range to kill them. That is metal as heck, but it’s also really hard on the body. It was rare for a Neanderthal to survive past 30, and by then he or she would look like an old, old person due to all the injuries sustained while hunting.

The authors of the marvelous book How to Think Like a Neandertal, which I’m drawing from quite a lot here, point out that Neanderthals and rodeo cowboys show similar patterns of injury over their lifetimes. And Neanderthals didn’t have hospitals and doctors they could visit.

While Neanderthals did make stone tools and use fire, analysis of their campsites shows sometimes interesting compared to human campsites. There’s no central fire pit. Almost every individual had their own fire where they did their own thing. In prehistoric human campsites, way back 25,000 years ago and even more, there’s generally one central fire that everyone gathers around. We still do this the world over. Can you even imagine going to summer camp and every kid spends the evening alone, tending their own little campfire and not singing camp songs, not spelling spooky stories, not eating s’mores together?

In addition, while there have been some controversial theories over some findings, as far as we can determine, Neanderthals didn’t make art. Some perforated seashells have been found at two Neanderthal sites in Spain that researchers think may have been worn as pendants, and we have evidence that Neanderthals, like other hominins for at least 300,000 years, used mineral pigments as body decoration. But they didn’t appear to use ceremonial items, didn’t create clothing beyond rough hide blankets or wraps, and they only had the barest minimum of funerary rites. Neanderthals may have been strong and smart, but they don’t appear to have been especially creative by our standards.

One old man Neanderthal, who was probably not more than 35 when he died, was so injured that he could probably not walk or do much of anything else by the final years of his life. He had lost most of his teeth and wouldn’t have been able to eat. But he lived for years, because someone helped him. Someone brought him food. Someone probably chewed it for him. And when he died, someone tucked him in a shallow hole and scattered dirt over his body. So however different Neanderthals were from us, they were also people.

By about 40,000 years ago, Neanderthals were extinct. That was probably too long ago to have left any traces in human collective memory, but that’s something I’ll bring up in part two of this episode next week.

We still don’t know much about the Denisovans because we only discovered the first specimen, a fragment of a finger bone, about ten years ago. The bone is from a young woman who lived about 41,000 years ago and was found in the Denisova Cave in Siberia, in the mountains not far from China and Mongolia. Since then, scientists have also found some teeth from two different adult males, and a baby tooth from a little girl who lived much earlier than the others.

According to DNA testing done on the finger bone, Woman X, as the finger’s owner is called, was neither a modern human nor a Neanderthal, although she was related to both and could interbreed with both. Denisovan DNA has been found in some populations of humans. Not only that, Woman X contained some Neanderthal DNA and DNA from an ancient human lineage that we don’t yet recognize. So there’s at least one other hominin we haven’t yet discovered. A toe bone has also been found that may be from a hybrid Denisovan-Neanderthal, but we don’t know for sure yet, since studies are still ongoing.

We don’t know what the Denisovans looked like, but just going from Woman X’s finger bone, which is much thicker than even a big human’s finger bones, we can guess they were pretty robust people. They may have looked a lot like Neanderthals. Some fossils thought to belong to Neanderthals may actually be Denisovan, so I bet a lot of museum and university collections are being examined closely right about now.

The Denisova Cave was used as a home by humans, Neanderthals, and Denisovans at different times going back some 125,000 years, and as recently as the 18th century, when a Russian hermit named Denis lived there. A bracelet discovered in the same layer of soil where Woman X’s finger bone was found has been dated to about the same time as the bone and is not a human artifact as far as archaeologists can tell.

It’s a green chlorite bracelet, carefully carved and beautifully polished. It was probably worn on the right wrist. It’s delicate, fragile, and probably belonged to someone important who wore it on important occasions. In other words, Denisovans wore and probably made jewelry. Unlike Neanderthals, they probably had important occasions.

A marble ring was found at the same time as the bracelet, but no information on it has been released yet. Hopefully, it won’t be long before we learn more about these new cousins of ours. They seem like interesting people.

That’s it for part one of our episode on humans. Next week we’ll take a look at some less closely related and more mysterious human relations, especially ones known as Hobbits for their small stature. Maybe by then you’ll have gotten that Toto song out of your head.

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 024: The Water Owl and the Devil Bird

This week’s episode is about two solved mysteries that aren’t exactly solved after all, the water owl and the devil bird! Let’s figure out what those two might really be!

Cuvier’s Beaked Whale:

A swordfish, swording everywhere it goes:

Seems definitive:

A possible culprit for the devil bird, the spot-bellied eagle owl:

The brown wood owl. Nice hair, dude.

Show transcript:

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

I got my air conditioning fixed, so you’ll be happy to know I’m not sitting in front of the microphone sweating like last week.

This week I wanted to look at a couple of animal mysteries that are supposedly solved. Imagine me cracking my knuckles to get down to business, because they’re not actually solved but you and I are going to solve them right now.

If you do a search for mythical animals that turned out to be real, the water owl is on just about every single one. The water owl is supposedly a huge sea monster with the body of a fish and the head of an owl, with big round eyes. According to the medieval myth, the water owl (also called the Xiphias) was supposed to ram ships with its sword-like beak, or slice through them with its huge dorsal fin.

According to those solve mystery animals lists, it turns out that the monster was really a Cuvier’s beaked whale. But in TH White’s 1960 translation of the Book of Beasts, a 12th century bestiary, Xiphias is clearly identified as a swordfish. Elsewhere it’s also called gladius, “so-called because he has a sharp pointed beak, which he sticks into ships and sinks them.” Not coincidentally, the swordfish’s scientific name is Xiphias gladius, which basically means “sword sword.”

Directly under the Gladius entry is that of the serra, which “is called this because he has a serrated cockscomb, and swimming under the vessels he saws them up.” I don’t know what the serra is supposed to be and neither does TH White. It’s possible it was a muddled account of the sawfish.

There is no entry for sea owl, water owl, or anything similar in any bestiary I could get my hands on. It’s possible that the Xiphias if medieval bestiaries and Cuvier’s beaked whale comes from the whale’s scientific name, Ziphius cavirostris, with Ziphius spelled differently from the swordfish’s Xiphias, although I’m pretty sure the pronunciation is the same. Xiphos means sword in Greek and the whale does have an elongated beak, although nothing like a swordfish’s, and not even very long compared to other beaked whales. Another common name for it is the goose-beaked whale, which is a lot more accurate.

Its face and its beak look nothing like an owl’s, nor does it have a very big dorsal fin. Cuvier’s beaked whale is a relatively common whale found throughout the world. It grows up to 23 feet long [or 7 meters] and can be gray, brown, or even a reddish color. It’s a deep diver and habitually feeds on squid and deep-sea fish. In fact, it holds the record for the longest and deepest recorded dive for any mammal—over two hours underwater and over 9800 feet deep [or nearly 3,000 meters]. That’s almost two miles. Its flippers fold back into depressions in its sides to reduce drag as it swims. Like other beaked whales it has no teeth except for two tusks in males that stick up from the tip of its lower jaw. Males use these tusks when fighting, and many whales have long scars on their sides as a result.

The swordfish also has no teeth, but it does have a hugely elongated bill that it uses not to spear fish, but to slash at them. It’s a fast, scary-looking fish that can grow up to 15 feet long [or 4.6 meters], and it does have a pronounced upright dorsal fin. And while its bill isn’t exactly owl-like, since owls all have short bills, it does have huge round eyes.

In other words, the water owl isn’t Cuvier’s beaked whale. It’s probably the swordfish. And if anyone can point me to a primary source that mentions an animal called the water owl, I’d be much obliged.

Like Cuvier’s beaked whale, the swordfish spends a lot of time in deep water. Its deepest recorded dive was over 9400 feet [or 2,865 meters], almost that of the deepest recorded whale dive. It eats fish, squid, and crustaceans, swallowing the smaller prey whole and slashing the larger prey up first.

One interesting note about the swordfish’s eyes. Like marlin, tuna, and some species of shark, the swordfish has a special organ that keeps its eyes and brain warmer than the surrounding water. This improves its vision, but it’s also really unusual in fish, which are almost exclusively cold-blooded.

Another animals that appears on the mythical animals found to be real list is the devilbird, also called the ulama. It’s a Sri Lankan bird whose call is supposed to be a death omen, and the spot-bellied eagle owl is supposed to be the actual bird with the eerie human-like scream. But that may not be the case.

So what is the legend? What bird might be behind it? And most importantly, what does it sound like?

The legend shares similarities with folk tales like La Llorona and the Banshee, and many others throughout the various cultures of the world. in the Sri Lankan legend, a man who thought his wife was cheating on him killed their infant son. His wife went insane, ran into the jungle, and died. The gods transformed her into the ulama bird, and now her terrible wailing warns others that they are doomed.

The trouble is, not only is no one sure which bird is actually the ulama, no one’s really sure what the ulama sounds like. Some accounts say it sounds like a little boy being strangled, others just say it’s a terrifying scream. What seems to be the case is that any creepy-sounding night bird call is said to be an ulama.

I did a search online and didn’t come up with much. This audio is the closest thing to a bona fide ulama call that I could find. Most of the calls in the video are hard to hear and there’s a lot of background noise, so I just snipped out the two best calls to give you an idea:

[creepy ulama call]

There are a lot of birds people think might be the ulama. The most common suggestion is the spot-bellied eagle owl, which nests in Sri Lanka although it doesn’t live there year-round. It is an adorable floof like an owls, with ear tufts and big dark eyes. It’s not spooky-looking, but it is spooky sounding. Here’s a sample of its call:

[owl call]

Then there’s the highland nightjar, the brown wood owl, the crested honey buzzard, the crested hawk eagle, and many others. The crested hawk eagle and crested honey buzzard are diurnal hunters, so are not likely to give their calls at night. The brown wood owl, which by the way looks like the spot-bellied eagle owl with an Afro instead of ear tufts, just hoots like a regular owl. The highland nightjar, also called the jungle nightjar, calls at dusk, and like all nightjars is hard to spot. It’s gray with black streaks and black-barred tail and wings. The problem is, it sounds like this:

[cute instead of creepy nightjar call]

That’s maybe a little spooky if you hear it at a lonely place at night, but not “I or a loved one am now doomed to die” kind of spooky. Supposedly the male’s flight call is more of a scream, but I couldn’t find any corroboration about that, and in fact every bird site I checked indicated the male’s flight call is more of a hooting sound.

So what is the ulama? Here’s my suggestion. It’s not a particular bird at all, but an interpretation of any number of bird and animal calls. If you hear an inhuman scream or wail in the night, and you know about the ulama legend, then that call is naturally an ulama call. It doesn’t matter that some other person on some other night might hear a completely different call and also know it’s the ulama. All terrifying cries in the night are the ulama.

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 023: Nonhuman Musicians

This week’s episode is about nonhuman musicians. It’s rarer than you’d think.

The palm cockatoo. Nature’s drummer. In possibly related news, I know what my next tattoo is going to be.

Snowball the Dancing Cockatoo.

Members of the Thai Elephant Orchestra at the Thai Elephant Conservation Center:

Further reading:

Kinship with Animals by Dave Soldier

Show transcript:

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

This week’s episode about nonhuman musicians was inspired by an article about palm cockatoos. The male cockatoos drum on tree trunks or hollow logs as part of their courtship display, which doesn’t sound all that unusual until you learn that they use special crafted sticks to drum. A male will select a stick, trim it down the way he wants it, and hold it in his claw to drum. Sometimes he’ll use a hard seedpod instead. The resulting beats are not only consistently in rhythm, each individual has a personal style. Some drum quickly, some slowly, some throw in little flourishes. Sometimes females will drum too, and if a female likes a male’s drumming, she may imitate him or join in.

Here’s a little clip of a male drumming. He’s also whistling.

[palm cockatoo drumming]

The palm cockatoo is an awesome-looking bird. It looks like a drummer. It’s up to two feet long, or 61 cm, smoky gray or gray-black with a heavy gray beak, red cheek patches that flush when the bird is upset or excited, and a messy crest of feathers. It’s native to Papua New Guinea, Indonesia, and the very northern tip of Australia, Cape York Peninsula. Only the Australian birds are known to drum. Unfortunately, the Australian birds are the ones most threatened in the wild due to habitat loss.

The palm cockatoo eats nuts and seeds, and like all parrots it can live a long time. And yes, you can get them as pets—and now I’m desperate for one even though the last thing I need is a pet cockatoo. I have a coworker with a pet parrot who she says is incredibly neurotic. He tends to get overexcited and starts screaming, and she has to put him in his cage and cover it so he’ll shut up. Her kids found the parrot when they were young. He plopped down in her yard when they were playing outside, and they put an empty laundry basket over him to trap him. No one claimed him, so my coworker has now been stuck with a neurotic parrot for over twenty years. She’s pretty sure he survived in the wild by hanging out with crows, because one of the things that will set off his excited screaming is hearing crows outside. And while cockatoos and parrots in general are typically affectionate and make good pets, palm cockatoos are not. They’re considered “difficult.” When parrot fanciers call a type of bird difficult, it’s difficult.

Anyway, the really unusual thing about the palm cockatoo’s drumming isn’t its tool use, which is well known among many types of birds, especially parrots and their relations. It’s the rhythm.

Most animals can’t keep a beat. Synchronization to an external rhythm is called rhythmic entrainment. Humans are really good at it and recognize a beat automatically, but responding in time to a rhythm is a learned skill. Small children have to learn to keep a beat by moving their bodies, speaking, or singing, and they learn it best in social settings. That’s why music, dance, and rhythmic play activities are so important to preschool children. And as a drummer myself, I promise you, humans of any age can learn to improve their rhythm.

But most animals don’t seem to have the ability to distinguish rhythmic beats, although it hasn’t been studied all that much until fairly recently. Some researchers think it may have something to do with the ability to mimic vocal sounds.

That would explain why many birds show rhythmic entrainment, varying from species to species. A sulfur-crested cockatoo named Snowball was internet-famous for a while in clips where the bird danced to music. As a result, Snowball became the subject of a rhythmic entrainment study that shows he can adapt his dancing to changing tempos.

But not all animals who show rhythmic entrainment can mimic vocally. California sea lions aren’t exactly the parrots of the sea animal world, but they can be trained to move to a beat. On the other hand, closely related seals are vocal learners. In fact, one famous harbor seal who was raised by a fisherman who found the orphaned pup could imitate the fisherman so well he was known as “Hoover the Talking Seal.”

Here’s the only clip I would find of Hoover. The first time I listened to it, I couldn’t figure out when the seal was talking. All I could hear was some gruff-sounding guy talking really fast. Well, that’s Hoover.

[Hoover the talking seal]

That is Hoover the talking seal talking. It’s creepy as heck.

It’s possible that sea lions still retain neural pathways that allow vocal mimicking even if they no longer use them. Then again, some researchers now believe that vocal mimicking ability may only be a skill related to rhythmic entrainment, not the source of the ability, and that the neural pathways for rhythmic entrainment may be very old. Some species can express entrainment, others appear to have lost it.

Studies on human brains show that when music plays, pretty much the entire brain lights up in response. That’s because we have special neural connections that help coordinate motor planning, speech, and other skills with the perceived beat. Brains of parrots and other birds are very similar. But monkeys are not. Monkeys can’t dance. Poor monkeys.

One study with rhesus monkeys who were trained to tap in rhythm with a metronome determined that they couldn’t anticipate the beat but could tap just after it, responding to it, even after years of training. Many rhythmic entrainment studies focus on great apes, since it’s reasonable to suppose that humans’ close cousins might share our rhythmic ability.

Patricia Grey, a bio-music researcher at the University of North Carolina at Greensboro, taught a group of captive bonobo apes to play a drum along with a beat. But it wasn’t as simple as showing a bonobo how a drum worked and seeing if it could keep a beat. She had to encourage the apes in a social setting, just like with human children. Also, she had to design a drum that could take a whole lot of abuse. I love that she went to Remo, a company that manufactures drums and drumheads, to have the drum made.

Her experiment started by accident. In 2010, Grey was at the Great Ape Research Center in Des Moines waiting for an experiment to be set up, and while she waited she idly tapped the glass on the bonobo enclosure. A bonobo named Kanzi came over and tapped her hand on the glass in response, matching Grey’s tempo. Intrigued, Grey continued tapping to see how long Kanzi would keep it up. Kanzi didn’t stop, even when her snack time came. She ate her snack lying on her back so she could continue to tap with her feet.

Wild chimpanzees and bonobos drum on logs and their own bodies to make rhythmic noise during play and dominance activities. Dominant male chimps do a particularly exaggerated slow display when thunderstorms approach, called a rain dance by researchers, that involves drumming. A variation of the rain dance has been seen when wildfires are approaching a troupe of chimps. Naturally it’s called a fire dance, and it includes a vocalization heard at no other time.

Chimps are pretty chill when it comes to fire, by the way. They understand how it spreads and how to avoid it without panicking.

Another animal that can keep the beat? Elephants! Asian elephants are vocal mimics and their ability to keep a beat is extremely precise. In 2000, the Thai Elephant Orchestra was created with elephants at a conservation center in Thailand, who learned to play oversized versions of traditional Thai percussion instruments.

The elephants learned the instruments easily, taking to it so quickly and so well that the orchestra’s founders were astonished. The great thing is, the elephants actually create much of the music themselves. The orchestra’s founders, neuroscientist Dave Soldier and elephant conservationist Richard Lair, wanted the elephants to have fun and enjoy making music. So for most songs, the animals are only signaled when to start and stop playing. Occasionally human musicians play along.

The orchestra released three albums between 2002 and 2011, which were all well received—not as novelty albums, but as actual improvisational compositions. Some of the songs are arranged, with the elephants trained to play traditional Thai music. The orchestra performs live for visitors at the conservation center.

The orchestra varies in size from five to fourteen elephants. One particularly talented drummer, Luk Kop, could play three drums at the same time and set up complex rhythms. Unfortunately he was also a dangerous elephant, and that’s not good for a band or an elephant orchestra, so he had to drop out.

The elephants prefer non-dissonant tones and learn to strike the properly resonant parts of their instruments without even being taught. The elephants at the center also enjoy playing harmonicas. The tip of an elephant’s trunk has a fingerlike projection, so an elephant can hold a harmonica and blow through it with its trunk. Soldier reports that one morning he arrived at the center early when the elephants were heading down to the river for their morning bath. Almost all the elephants had brought their harmonicas and were playing together as they walked.

Most of the elephants at the center are former logging animals, and many of their handlers, known as mahouts, once worked with them when they were logging. Mahouts traditionally sing to their elephants, which is supposed to keep them calm. So the elephants in the orchestra are familiar with traditional Thai music.

Locals who have heard the orchestra play say the music sounds like the music in Buddhist temples. Soldier, a musician and composer himself, transcribed an original elephant piece which was then played by a human orchestra in New York. The audience didn’t know it was composed by elephants. Some guesses as to who the composer might be included John Cage, Dvorak, and Charles Ives.

Whether or not you like improvisational Thai music played by elephants, or you think it’s just a stupid gimmick, it’s clear the elephants are having a lot of fun. Here’s a clip of some of their music recorded at the conservation center. That’s some mighty fine percussion for animals who don’t even have hands.

[elephant orchestra]

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 022: Megatherium

Episode 22 is all about megatherium, the giant extinct ground sloth–and a little bit about glyptodon, the giant extinct…thing.

Megatherium vs trees was basically no contest. Giant ground sloth FTW!

Giant sloth big, yeah yeah yeah, it’s not small, no no no

Glyptodon. Like a giant armadillo that can’t roll up and doesn’t need to.

Show transcript:

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

For this week’s episode, let’s learn about some Ice Age megafauna! But first, a quick note about my schedule. I’ll talk more about this in a few weeks, but in August I’m going to be in Helsinki, Finland for WorldCon 75. I don’t have the final schedule yet, but I am going to be on a panel about podcasting. If you’re going to WorldCon too, or if you’ll be in Helsinki the week of the convention or the week after, let me know so we can meet up! I’ll also be in Oslo, Norway for part of the day on August 7. I got a cheap flight to Helsinki because it has an 11-hour layover in Oslo, but to me that’s a bonus. Oslo has birds! Birds I’ve never seen before! So if you’re going to be in Oslo on August 7 and you’d like to meet me for a birding trip and/or lunch, definitely let me know! And don’t worry, I’ll schedule episodes ahead of time so you can continue to learn about strange animals even while I’m gone.

Now, on to the megafauna. Until about five million years ago, South America was a big island continent the way Australia is today. As a result, many of the animals that evolved there at the time don’t look anything like animals in other parts of the world.

The various species of giant ground sloth, such as Megatherium and Eremotherium, were South American mammals that lived from around 30 million years ago until only about 10,000 years ago—but we’ll come back to that in a minute. Those two species were huge—as big as African elephants. It was 20 feet long and stood more than 12 feet high on its hind legs. They liked woodlands and grasslands and ate plants.

Megatherium had huge curved claws on its forefeet just like modern sloths, four claws that were a foot long each, and we know it walked on the sides of its paws as a result because we have some fossilized tracks. A ground sloth could walk on its hind legs, at least for short distances, and when feeding it spent a lot of its time reared up on its hind legs, helped to balance by its thick tail. It could reach branches some 20 feet off the ground that way. It hooked the branches down with its claws to eat the leaves.

Around 5 million years ago, South America became connected to North America by the Central American Isthmus, which is volcanic in origin. Over the millennia, peaking around 3 million years ago, North American animals migrated south, and South American animals migrated north, called the Great American interchange. A lot of South American megafauna went extinct with the increased competition for resources, but nothing bothered the giant ground sloths. One medium-sized species, named Megalonyx by Thomas Jefferson, spread throughout North America as far north as Alaska. It was “only” about 10 feet long and weighed some 800 pounds, with three claws on its forefeet.

The North American sloths died out first, around 11,000 years ago. It didn’t take long for most of the South American sloths to go extinct too, a little over 10,000 years ago. And yes, that was the same time that humans were spreading deeper into the Americas. It’s not a coincidence, although climate change after the last big ice age probably played a part too. Ground sloths had thick skin reinforced with osteoderms, knobs of bone tissue that grow in the skin like armor, so killing one would have been a lot of work for our ancestors, and was undoubtedly dangerous too.

But a whole lot of islands make up the Carribbean, and giant sloths lived on some of those islands. Many had developed in isolation long enough that they’re now considered separate species from the mainland sloths. And many of the island sloths persisted for thousands of years after their gigantic mainland cousins were long dead.

The island sloths were much smaller than Megatherium. Megalocnus only weighed about 200 pounds—a big sloth, but nothing like the five tons that Megatherium could weigh. But Megalocnus survived until some 6,000 years ago in Cuba and maybe much more recently. Another Cuban sloth lived another thousand years after that. A small ground sloth called Neocnus survived on Hispanolia until only about 4,500 years ago.

You may have heard recently about a lot of huge tunnels in Brazil. Until recently, people assumed they were natural caves. It wasn’t until the 2000s that geologists started investigating the tunnels and immediately saw that they weren’t natural at all. They were burrows, many with claw marks on the walls as though just dug, thousands of them scattered across Brazil and a few other parts of South America. Some are tall enough to stand up inside comfortably. One paleoburrow in the Amazon is a network that adds up to around 2,000 feet of tunnels, six feet tall and almost that wide. It was probably used by generations of animals, enlarged and extended as new adults dug their own burrows.

The burrows were probably dug by giant sloths. No one is sure why. Giant sloths had no predators until humans moved into the area. But it’s also possible that some or most of the burrows were dug by the extinct ancestors of armadillos, glyptodon.

The glyptodonts are related to both the giant ground sloths and modern-day armadillos. Glyptodon and its two related species, Panochthus and Doedicurus, lived in the same areas where the giant burrows have been discovered. And modern armadillos are good burrowers. But Glyptodon had even less reason to need burrows than giant ground sloths did. It was an enormous animal, 11 feet long and five feet high, weighing over two tons, with a massive domed carapace like a tortoise shell, made of rows of osteoderms. It also had osteoderms that protected its head like a cap, and rings of bony plates on the end of its thick tail that made it into a club-like weapon. Even its jaws contained osteoderm ridges, which helped grind up the plants it ate, although it also had huge grooved teeth.

In other words, glyptodon was a walking tank. Nothing much ate them until humans showed up. A full-grown glyptodon was a bonanza for humans if they could kill it. Not only did it provide a whole lot of meat, its shell could be used as shelter. Clean it out good first. At least one human burial has been found in a glyptodon shell.

Considering how amazing glyptodonts are, you’d think they’d be more well known and better studied. There’s still a whole lot we don’t know about them, including how many species there actually were and how recently they died out. There aren’t even very many reported sightings of living ones, which tends to happen with just about any extinct animal.

Giant ground sloths, on the other hand, do get reported every so often, and there are hints that giant ground sloths might have lived until much more recently than ten or eleven thousand years ago. Megatherium remains found in caves sometimes seem suspiciously fresh, although so far radiocarbon dating hasn’t given us any surprises. In 1740 the Portuguese historian Lozano mentioned an animal that sounds a little like a ground sloth, which was supposedly called the su by locals.

Some cryptozoologists believe that a legendary South American monster, the mapinguari, may have been inspired by megatherium. The mapinguari is supposed to be nine feet tall and smelly, with feet that face backwards, an extra mouth in its belly, skin that deflects arrows, and sometimes it’s said to have only one eye in the middle of its forehead. It also eats meat. That sounds a little on the far-fetched side to me, and a lot of cryptozoologists group the mapinguari with bigfoot type monsters.

There is another monster story from Patagonia that sounds a lot more sloth-like on the surface. The yemisch is supposed to be a cow-sized animal that sleeps in burrows it digs with its huge claws. It can’t be killed because arrows bounce off its hide. In fact, yemisch is supposed to mean “the one covered in little stones.”

That sounds promising, but the story comes exclusively from a man called Florentino Ameghino, who was convinced that a smaller giant ground sloth named mylodon still lived in Patagonia. The first mention anywhere of the Yemisch comes from Ameghino’s 1898 paper about mylodon, where he said the Tehuelche of Patagonia referred to it as the water tiger. It was semi-aquatic, spending much of its time in the river. It was said to drag horses into the water with its huge claws. Its feet were flat, its ears tiny, it had huge claws and fangs, and its toes were webbed for swimming. It was bigger than a puma but with shorter legs.

This doesn’t sound like a ground sloth, which were not carnivores despite their big claws. In 1900 a French naturalist, Andrew Tournouer, spotted an animal in a stream that looked a lot like Ameghino’s description of the Yemisch. Tournouer said it was definitely not a ground sloth; his guide said it was called a Hymche.

The water tiger Ameghino describes is well known in Patagonian native lore, but not under the name Yemisch. It’s possible Ameghino mangled the word Hymche. Whatever the water tiger is, though, it’s definitely not a giant ground sloth and I’m going to save it for a future episode if I can dig up more about it.

There was an aquatic giant ground sloth once, though, Thalassocnus. It grew to around five or six feet long and lived off the Pacific coast of South America, where it ate seaweed and other marine plants. Fossils document how it adapted to marine life over the generations. 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. It died out around two and a half million years ago, after the Isthmus of Panama formed, probably because the new land mass caused the water temperature to cool and many of the ocean plants in its habitat went extinct.

Whether or not any giant ground sloths are still alive in the remote parts of South America, I think we can all agree that they’re not going to eat anyone. So if you see one, don’t shoot it unless it’s with a camera.

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

Thanks for listening!