Category Archives: fossils

Episode 338: Updates 6 and an Arboreal Clam!?!

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This week we have our annual updates and corrections episode, and at the end of the episode we’ll learn about a really weird clam I didn’t even think was real at first.

Thanks to Simon and Anbo for sending in some corrections!

Further reading:

Lessons on transparency from the glass frog

Hidden, never-before-seen penguin colony spotted from space

Rare wild asses spotted near China-Mongolia border

Aye-Ayes Use Their Elongated Fingers to Pick Their Nose

Homo sapiens likely arose from multiple closely related populations

Scientists Find Earliest Evidence of Hominins Cooking with Fire

153,000-Year-Old Homo sapiens Footprint Discovered in South Africa

Newly-Discovered Tyrannosaur Species Fills Gap in Lineage Leading to Tyrannosaurus rex

Earth’s First Vertebrate Superpredator Was Shorter and Stouter than Previously Thought

252-Million-Year-Old Insect-Damaged Leaves Reveal First Fossil Evidence of Foliar Nyctinasty

The other paleo diet: Rare discovery of dinosaur remains preserved with its last meal

The Mongolian wild ass:

The giant barb fish [photo from this site]:

Enigmonia aenigmatica, AKA the mangrove jingle shell, on a leaf:

Show transcript:

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

This week is our annual updates and corrections episode, but we’ll also learn about the mangrove jingle shell, a clam that lives in TREES. A quick reminder that this isn’t a comprehensive updates episode, because that would take 100 years to prepare and would be hours and hours long, and I don’t have that kind of time. It’s just whatever caught my eye during the last year that I thought was interesting.

First, we have a few corrections. Anbo emailed me recently with a correction from episode 158. No one else caught this, as far as I can remember. In that episode I said that geckos don’t have eyelids, and for the most part that’s true. But there’s one family of geckos that does have eyelids, Eublepharidae. This includes the leopard gecko, and that lines up with Anbo’s report of having a pet leopard gecko who definitely blinked its eyes. This family of geckos are sometimes even called eyelid geckos. Also, Anbo, I apologize for mispronouncing your name in last week’s episode about shrimp.

After episode 307, about the coquí and glass frogs, Simon pointed out that Hawaii doesn’t actually have any native frogs or amphibians at all. It doesn’t even have any native reptiles unless you count sea snakes and sea turtles. The coqui frog is an invasive species introduced by humans, and because it has no natural predators in Hawaii it has disrupted the native ecosystem in many places, eating all the available insects. Three of the Hawaiian islands remain free of the frogs, and conservationists are working to keep it that way while also figuring out ways to get them off of the other islands. Simon also sent me the chapter of the book he’s working on that talks about island frogs, and I hope the book is published soon because it is so much fun to read!

Speaking of frogs, one week after episode 307, an article about yet another way the glass frog is able to hide from predators was published in Science. When a glass frog is active, its blood is normal, but when it settles down to sleep, the red blood cells in its blood collect in its liver. The liver is covered with teensy guanine crystals that scatter light, which hides the red color from view. That makes the frog look even more green and leaf-like!

We’ve talked about penguins in several episodes, and emperor penguins specifically in episode 78. The emperor penguin lives in Antarctica and is threatened by climate change as the earth’s climate warms and more and more ice melts. We actually don’t know all that much about the emperor penguin because it lives in a part of the world that’s difficult for humans to explore. In December 2022, a geologist named Peter Fretwell was studying satellite photos of Antarctica to measure the loss of sea ice when he noticed something strange. Some of the ice had brown stains.

Dr Fretwell knew exactly what those stains were: emperor penguin poop. When he obtained higher-resolution photos, he was able to zoom in and see the emperor penguins themselves. But this wasn’t a colony he knew about. It was a completely undiscovered colony.

In episode 292 we talked about a mystery animal called the kunga, and in that episode we also talked a lot about domestic and wild donkeys. We didn’t cover the Mongolian wild ass in that one, but it’s very similar to wild asses in other parts of the world. It’s also called the Mongolian khulan. It used to be a lot more widespread than it is now, but these days it only lives in southern Mongolia and northern China. It’s increasingly threatened by habitat loss, climate change, and poaching, even though it’s a protected animal in both Mongolia and China.

In February of 2023, a small herd of eight Mongolian wild asses were spotted along the border of both countries, in a nature reserve. A local herdsman noticed them first and put hay out to make sure the donkeys had enough to eat. The nature reserve has a water station for wild animals to drink from, and has better grazing these days after grassland ecology measures were put into place several years ago.

In episode 233 we talked about the aye-aye of Madagascar, which has weird elongated fingers. Its middle finger is even longer and much thinner than the others, which it uses to pull invertebrates from under tree bark and other tiny crevices. Well, in October of 2022 researchers studying aye-ayes started documenting another use for this long thin finger. The aye-ayes used it to pick their noses. It wasn’t just one aye-aye that wasn’t taught good manners, it was widespread. And I hope you’re not snacking while I tell you this, the aye-aye would then lick its finger clean. Yeah. But the weirdest thing is that the aye-aye’s thin finger is so long that it can potentially reach right through the nose right down into the aye-aye’s throat.

It’s pretty funny and gross, but wondering why some animals pick their noses is a valid scientific question. A lot of apes and monkeys pick their noses, as do humans (not that we admit it most of the time), and now we know aye-ayes do too. The aye-aye is a type of lemur and therefore a primate, but it’s not very closely related to apes and monkeys. Is this just a primate habit or is it only seen in primates because we have fingers that fit into our nostrils? Would all mammals pick their nose if they had fingers that would fit up in there? Sometimes if you have a dried snot stuck in your nose, it’s uncomfortable, but picking your nose can also spread germs if your fingers are dirty. So it’s still a mystery why the aye-aye does it.

A recent article in Nature suggests that Homo sapiens, our own species, may have evolved not from a single species of early human but from the hybridization of several early human species. We already know that humans interbred with Neandertals and Denisovans, but we’re talking about hybridization that happened long before that between hominin species that were even more closely related.

The most genetically diverse population of humans alive today are the Nama people who live in southern Africa, and the reason they’re so genetically diverse is that their ancestors have lived in that part of Africa since humans evolved. Populations that migrated away from the area, whether to different parts of Africa or other parts of the world, had a smaller gene pool to draw from as they moved farther and farther away from where most humans lived.

Now, a new genetic study of modern Nama people has looked at changes in DNA that indicate the ancestry of all humans. The results suggest that before about 120,000 to 135,000 years ago, there was more than one species of human, but that they were all extremely closely related. Since these were all humans, even though they were ancient humans and slightly different genetically, it’s probable that the different groups traded with each other or hunted together, and undoubtedly people from different groups fell in love just the way people do today. Over the generations, all this interbreeding resulted in one genetically stable population of Homo sapiens that has led to modern humans that you see everywhere today. To be clear, as I always point out, no matter where people live or what they look like, all people alive today are genetically human, with only minor variations in our genetic makeup. It’s just that the Nama people still retain a lot of clues about our very distant ancestry that other populations no longer show.

To remind everyone how awesome out distant ancestors were, here’s one new finding of how ancient humans lived. We know that early humans and Neandertals were cooking their food at least 170,000 years ago, but recently archaeologists found the remains of an early hominin settlement in what is now Israel where people were cooking fish 780,000 years ago. There were different species of fish remains found along with the remains of cooking fires, and some of the fish are ones that have since gone extinct. One was a carp-like fish called the giant barb that could grow 10 feet long, or 3 meters.

In other ancient human news, the oldest human footprint was discovered recently in South Africa. You’d think that we would have lots of ancient human footprints, but that’s actually not the case when it comes to footprints more than 50,000 years old. There are only 14 human footprints older than that, although there are older footprints found made by ancestors of modern humans. The newly discovered footprint dates to 153,000 years ago.

It wouldn’t be an updates episode without mentioning Tyrannosaurus rex. In late 2022 a newly discovered tyrannosaurid was described. It lived about 76 million years ago in what is now Montana in the United States, and while it wasn’t as big as T. rex, it was still plenty big. It probably stood about seven feet high at the hip, or a little over 2 meters, and might have been 30 feet long, or 9 meters. It probably wasn’t a direct ancestor of T. rex, just a closely related cousin, although we don’t know for sure yet. It’s called Daspletosaurus wilsoni and it shows some traits that are found in older Tyrannosaur relations but some that were more modern at the time.

Dunkleosteus is one of a number of huge armored fish that lived in the Devonian period, about 360 million years ago. We talked about it way back in episode 33, back in 2017, and at that time paleontologists thought Dunkleosteus terrelli might have grown over 30 feet long, or 9 meters. It had a heavily armored head but its skeleton was made of cartilage like a shark’s, and cartilage doesn’t generally fossilize, so while we have well-preserved head plates, we don’t know much about the rest of its body.

With the publication in early 2023 of a new study about dunkleosteus’s size, we’re pretty sure that 30 feet was a huge overestimation. It was probably less than half that length, maybe up to 13 feet long, or almost 4 meters. Previous size estimates used sharks as size models, but dunkleosteus would have been shaped more like a tuna. Maybe you think of tuna as a fish that makes a yummy sandwich, but tuna are actually huge and powerful predators that can grow up to 10 feet long, or 3 meters. Tuna are also much heavier and bigger around than sharks, and that was probably true for dunkleosteus too. The study’s lead even says dunkleosteus was built like a wrecking ball, and points out that it was probably the biggest animal alive at the time. I’m also happy to report that people have started calling it chunk-a-dunk.

We talked about trace fossils in episode 103. Scientists can learn a lot from trace fossils, which is a broad term that encompasses things like footprints, burrows, poops, and even toothmarks. Recently a new study looked at insect damage on leaves dating back 252 million years and learned something really interesting. Some modern plants fold up their leaves at night, called foliar nyctinasty, which is sometimes referred to as sleeping. The plant isn’t asleep in the same way that an animal falls asleep, but “sleeping” is a lot easier to say than foliar nyctinasty. Researchers didn’t know if folding leaves at night was a modern trait or if it’s been around for a long time in some plants. Lots of fossilized leaves are folded over, but we can’t tell if that happened after the leaf fell off its plant or after the plant died.

Then a team of paleontologists from China and Sweden studying insect damage to leaves noticed that some leaves had identical damage on both sides, exactly as though the leaf had been folded and an insect had eaten right through it. That’s something that happens in modern plants when they’re asleep and the leaves are folded closed.

The team looked at fossilized leaves from a group of trees called gigantopterids, which lived between 300 and 250 million years ago. They’re extinct now but were advanced plants at the time, some of the earliest flowering plants. They also happen to have really big leaves that often show insect damage. The team determined that the trees probably did fold their leaves while sleeping.

In episode 151 we talked about fossils found with other fossils inside them. Basically it’s when a fossil is so well preserved that the contents of the dead animal’s digestive system are preserved. This is incredibly rare, naturally, but recently a new one was discovered.

Microraptor was a dinosaur that was only about the size of a modern crow, one of the smallest dinosaurs, and it probably looked a lot like a weird bird. It could fly, although probably not very well compared to modern birds, and in addition to front legs that were modified to form wings, its back legs also had long feathers to form a second set of wings.

Several exceptionally well preserved Microraptor fossils have been discovered in China, some of them with parts of their last meals in the stomach area, including a fish, a bird, and a lizard, so we knew they were generalist predators when it came to what they would eat. Now we have another Microraptor fossil with the fossilized foot of a mammal in the place where the dinosaur’s stomach once was. So we know that Microraptor ate mammals as well as anything else it could catch, although we don’t know what kind of mammal this particular leg belonged to. It may be a new species.

Let’s finish with the mangrove jingle shell. I’ve had it on the list for a long time with a lot of question marks after it. It’s a clam that lives in trees, and I actually thought it might be an animal made up for an April fool’s joke. But no, it’s a real clam that really does live in trees.

The mangrove jingle shell lives on the mangrove tree. Mangroves are adapted to live in brackish water, meaning a mixture of fresh and salt water, or even fully salt water. They mostly live in tropical or subtropical climates along coasts, and especially like to live in waterways where there’s a tide. The tide brings freshly oxygenated water to its roots. A mangrove tree needs oxygen to survive just like animals do, but it has trouble getting enough through its roots when they’re underwater. Its root system is extensive and complicated, with special types of roots that help it stay upright when the tide goes out and special roots called pneumatophores, which stick up above the water or soil and act as straws, allowing the tree to absorb plenty of oxygen from the air even when the rest of the root system is underwater. These pneumatophores are sometimes called knees, but different species of mangrove have different pneumatophore shapes and sizes.

One interesting thing about the mangrove tree is that its seeds actually sprout while they’re still attached to the parent tree. When it’s big enough, the seedling drops off its tree into the water and can float around for a long time before it finds somewhere to root. If can even survive drying out for a year or more.

The mangrove jingle shell clam lives in tropical areas of the Indo-Pacific Ocean, and is found throughout much of coastal southeast Asia all the way down to parts of Australia. It grows a little over one inch long, or 3 cm, and like other clams it finds a place to anchor itself so that water flows past it all the time and it can filter tiny food particles from the water. It especially likes intertidal areas, which happens to be the same area that mangroves especially like.

Larval jingle shells can swim, but they need to find somewhere solid to anchor themselves as they mature. When a larva finds a mangrove root, it attaches itself and grows a domed shell. If it finds a mangrove leaf, since mangrove branches often trail into the water, it attaches itself to the underside and grows a flatter shell. Clams attached to leaves are lighter in color than clams attached to roots or branches. Fortunately, the mangrove is an evergreen tree that doesn’t drop its leaves every year.

So there you have it. Arboreal clams! Not a hoax or an April fool’s joke.

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 330: Vintana and Tiarajudens

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Thanks to Lorenzo for suggesting Tiarajudens! We’ll learn about it this week along with another extinct animal, Vintana.

Further reading:

Funky facial flanges [the skull picture below comes from this site]

First Postcranial Fossils of Rare Gondwanatherian Mammal Unearthed in Madagascar

The Earliest Saberteeth Were for Fighting, Not Biting [the skeleton picture below comes from this site]

Vintana’s skull had weird jugal flanges:

Tiarajudens had saber teeth as well as palatal teeth:

Show transcript:

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

Just last month we had an episode about the tenrec and an extinct animal called Adalatherium. At the end of that episode, I said something I say a lot, that we don’t know very much about it or the other ancient mammals that lived at the time, and that I hoped we would find some new fossils soon. Well, guess what! A paper about a newly discovered Gondwanathere fossil was published just a few days ago as this episode goes live. Rather than save it for the updates episode later this summer, let’s learn about an animal named Vintana sertichi, along with a suggestion from Lorenzo for another extinct animal.

As you may remember from episode 324, Adalatherium is a member of a group of animals 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, although we do know they’re not related to the mammals living today. Every new specimen found of these rare mammals helps scientists fill the gaps in our knowledge. That’s what happened with Vintana.

Vintana lived at the end of the Cretaceous, until the asteroid strike about 66 million years ago that killed off the non-avian dinosaurs and a whole lot of other animals, probably including Vintana. The first fossilized specimen was a skull found in Madagascar and described in 2014. It was really well preserved, which allowed scientists to learn a lot about the animal.

Vintana was an active animal that ate plants. It had large eyes and a good sense of smell and hearing, so its ears might have been fairly large too. Its face probably looked a lot like a big rodent’s face, but the skull itself had a weird feature. The cheekbones extended downward on each side next to the jaw, and these extensions are called jugal flanges. They would have allowed for the attachment of really big jaw muscles. That suggests that Vintana could probably give you a nasty bite, not that you need to worry about that unless you find a time machine. It might also mean that Vintana ate tough plants that required a lot of chewing.

Vintana probably looked a lot like a groundhog, or marmot, which we talked about recently in episode 327. It wasn’t related to the groundhog, though, and was bigger too. Scientists estimate it weighed about 20 lbs, or 9 kg.

The fossil specimen of Adalatherium that we talked about in episode 324 was discovered in Madagascar in 2020. When a tail vertebra from another mammal was found in the same area, researchers scanned and compared it to Adalatherium’s vertebrae. They were similar but not an exact match, plus the new bone was almost twice as large as the same bone in Adalatherium’s spine. It matched the size of Vintana and was assigned to that species. Vintana was probably related to Adalatherium but was bigger and had a shorter, wider tail. And as of right now, that’s just about all we know about it.

Next, let’s learn about another extinct animal, this one suggested by Lorenzo. Lorenzo gave me a bunch of great suggestions and I picked this one to pair with Vintana, because otherwise this episode would have been really short. Vintana lived at the end of the dinosaurs, but Tiarajudens lived long before the dinosaurs evolved, around 260 million years ago.

Tiarajudens was a therapsid, a group that eventually gave rise to mammals although it’s not a direct ancestor of mammals. Technically it’s an anomodont. We don’t have a complete skeleton so we don’t know for sure how big it was, but we do have a skull and some leg bones so we know it was about the same size or a little bigger than a big dog. There are only two species known, one from what is now South America and one from what is now Africa, but 260 million years ago those two landmasses were connected and were part of the supercontinent Gondwana.

Tiarajudens had weird teeth even compared to other anomodonts. It had a pair of saber teeth that resembled the tusks found in later anomodonts, but they weren’t really tusks. They were big fangs that grew from the upper jaw and jutted down out of the mouth well past the bottom of the jaw. Later anomodonts probably used their tusks to dig up plants, but there aren’t wear marks on Tiarajudens’s saber teeth that would indicate it used them for digging. Many paleontologists think it used them for defense and to fight other Tiarajudenses over mates or territory. We don’t know if the saber teeth were present in all individuals, since we’ve only found a few specimens.

Tiarajudens also had palatal teeth. These days palatal teeth are mostly found in amphibians, especially frogs. Palatal teeth grow down from the roof of the mouth and Tiarajudens’s were flat like molars. We haven’t found a lower jaw yet so we don’t know what the bottom teeth looked like, but from the wear marks on the upper teeth, it was clear that Tiarajudens was actually chewing its food. That was really unusual among all animals at the time, and in fact Tiarajudens is one of the first animals to really chew its food instead of giving it a chomp or two and swallowing it mostly whole. It ate plants, probably tough ones that required a lot of chewing.

So what did Tiarajudens look like beyond its teeth? It probably resembled a bulky four-legged dinosaur with a short tail, but it may have had whiskers. That’s as much as we know right now, because Tiarajudens was not only an early therapsid, it was different in many ways from most other therapsids known. For instance, it had what are called gastralia, or belly ribs, which were once common in tetrapods. Some dinosaurs had gastralia, including T. rex, but most therapsids didn’t. These days crocodiles and their relations still have gastralia, and so does the tuatara, but most animals don’t.

Both Tiarajudens and Vintana were unusual animals that we just don’t know much about. Let’s hope that changes soon and scientists find more fossils of both. I’ll keep you updated.

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 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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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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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!