Episode 461: Therizinosaurus and Its CLAWS

Further reading:

Study: Giant Therizinosaurs Used Their Meter-Long, Sickle-Like Claws for Display

Show transcript:

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

I am delighted to report that Therizinosaurus lived in what is now Mongolia in Central Asia, in the Gobi Desert. 70 million years ago, the land wasn’t a desert at all but a forest with multiple rivers and streams flowing through it. Lots of other dinosaurs and birds lived in the area, including a tyrannosaurid called Tarbosaurus that was probably the only predator big enough to kill Therizinosaurus.

When the first Therizinosaurus fossils were discovered in the 1950s, they were initially thought to belong to a type of giant turtle. Later it was reclassified as a sauropod relation, not a turtle. These days, we know for sure it’s not a turtle and we’re pretty sure it’s not anything like a sauropod.

The Therizinosaurus fossils found so far are incomplete. All we have are some ribs, one hind foot, and mostly complete arms and hands. We don’t have any parts of the skull or any vertebrae, so paleontologists still have a lot of questions about what Therizinosaurus looked like and how it lived, although we have more complete specimens of some of its close relations to help scientists make good guesses. Luckily we have its hands, because its claws are enormous. Therizinosaurus had claws bigger than any other dinosaur known.

Therizinosaurus was a big dinosaur overall, with an estimated length of 33 feet, or 10 meters, although until a more complete specimen is discovered we can’t know for sure how big it really was. It may have stood up to 16 feet tall, or 5 meters, and walked on its hind legs. It’s classified as a theropod these days, a group that includes famous dinosaurs like T. rex and Spinosaurus, but it wasn’t closely related to those big fast meat-eaters. Most paleontologists think Therizinosaurus ate plants, but again, we don’t know for sure since we don’t have any of its teeth to examine. Its closest relatives were herbivorous but its immediate ancestors were carnivorous.

If Therizinosaurus was a plant-eater, why did it have such enormous claws? Its claws were seriously terrifying! Its arms were big and strong in general, measuring about 8 feet long, or 2.5 meters, including long, slender fingers, and the claws measured over three feet long! That’s more than a meter long. If the claws were covered with a keratin sheath, which is probable, they would have been even longer when Therizinosaurus was alive. They were relatively thin and straight with a curve at the end.

There are many reasons why an animal develops big claws. Predators need claws to help grab prey or tear meat into pieces, or an animal may need big claws to help it dig or climb trees. Claws are also great for defense. Some animals use claws to grab tree branches and bend them closer to the animal’s mouth, which is something that giant ground sloths probably did, at least sometimes.

The new study published in February 2023 examined the claws of Therizinosaurus and lots of other dinosaurs to learn how strong they were. The claws were 3D scanned, and then the scans were used in various models that measured the stress placed on each claw in various different activities.

The study discovered that the claws of different dinosaurs were strong in different ways depending on what they were used for, which wasn’t a surprise. What was a surprise was that Therizinosaurus’s claws were weak no matter which model the scientists used.

In other words, Therizinosaurus probably didn’t use its claws to fight other dinosaurs unless it just had to, because they would break too easily. It wouldn’t have dug with its claws or even used them to hook branches down closer to its mouth. As far as we can tell, its claws were basically useless.

But obviously, Therizinosaurus used its claws for something or it wouldn’t have evolved to have such gigantic claws. The study concluded that the giant claws must have been for display, to attract a mate or maybe just scare off potential predators.

Lots of animals have special features used to attract a mate, like a peacock’s tail. Sometimes these features serve a double purpose, like a male deer’s antlers. The size of the antlers show how healthy he is, and he also uses them to fight other males. I’m not a claw expert, but as far as I know there aren’t any other animals known that use their claws for display only.

It’s possible that Therizinosaurus did use its claws for something else, we just don’t know what. It’s also possible that the study had flaws that a follow-up study will discover, and Therizinosaurus’s claws weren’t actually so weak. But for now, as far as we know, during mating season Therizinosaurus would strut around waving its super-long claws to show how amazing it was. And, let’s face it, Therizinosaurus really was amazing.

Thanks for your support, and thanks for listening!

Episode 459: Strange Little Dolphins

Thanks to Alexandra, Jayson, and Eilee for their suggestions this week!

Further reading:

Scientists have discovered an ancient whale species. It may have looked like a mash-up of ‘a seal and a Pokémon’

The nomenclatural status of the Alula whale

Field Guide of Whales and Dolphins [1971]

The little Benguela dolphin [photo taken from this site]:

The spinner dolphin almost looks like it has racing stripes [photo by Alexander Vasenin – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=25108509]:

The Alula whale, which may or may not exist:

Show transcript:

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

This week let’s learn about some whales and dolphins, including an ancient whale and a mystery whale, all of them really small. Thanks to Alexandra, Eilee, and Jayson for their suggestions!

Let’s start with an ancient whale, suggested by Jayson. The genus Janjucetus has been known since its first species was described in 2006, after a teenage surfer in Australia discovered the fossils in the late 1990s. It grew to about 11 feet long, or 3.5 meters, and lived about 25 million years ago. So far it’s only been found around Australia. But much more recently, just a few months ago as this episode goes live, a new species was described. That’s Janjucetus dullardi, also found in Australia along the same beach where the first Janjucetus species was found, and dating to around the same time period.

We don’t know a lot about the newly described whale, since it’s only known from some teeth and partial skull. Scientists think the individual was a juvenile and estimate it was only around 6 feet long when it died, or 2.8 meters. Small as it was, it would have been a formidable hunter when it was alive. Its broad snout was shaped sort of like a shark’s and it had strong, sharp teeth and large eyes.

Because it was an early whale, it wouldn’t have looked much like the whales alive today. It might even have had tiny vestigial back legs. Its eyes were huge in proportion to its head, about the size of tennis balls, and it probably relied on its eyesight to hunt prey because it couldn’t echolocate.

Its serrated teeth and strong jaws indicate that it might have hunted large animals, but some scientists suggest it could also filter feed the same way a crabeater seal does. Modern crabeater seals have similar teeth as Janjucetus, as do a few other seals. The projections on its teeth interlock when the seal closes its mouth, so to filter feed the seal takes a big mouthful of water, closes its teeth, and uses its tongue to force water out through its teeth. Amphipods and other tiny animals get caught against the teeth and the seal swallows them.

If Janjucetus did filter feed, it probably also hunted larger animals. Otherwise its jaws wouldn’t have been so strong or its teeth so deeply rooted. But Janjucetus wasn’t related to modern toothed whales. While it wasn’t a direct ancestor of modern baleen whales, it was part of the baleen whale’s family tree. Baleen whales, also called mysticetes, have baleen plates made of keratin instead of teeth. After the whale fills its mouth with water, it closes its jaws, pushes its enormous tongue up, and forces all that water out through the baleen. Any tiny animals like krill, copepods, small squid, small fish, and so on, get trapped in the baleen. It’s just like the crabeater seal, but really specialized and way bigger.

Whether or not Janjucetus could and did filter feed doesn’t really matter, because the fact that it’s an ancestral relation of modern baleen whales but it had teeth helps us understand more about modern whales.

Next, Eilee wanted to learn about the Benguela [BEN-gull-uh] dolphin, also called Heaviside’s dolphin. It lives only off the southwestern coast of Africa, and it’s really small, only a little over 5 and a half feet long at the most, or 1.7 meters. It’s dark gray with white markings, with a blunt head that’s almost cone-shaped and a triangular dorsal fin.

The Benguela dolphin is named for its ecosystem. The Benguela current flows northward along the coast, bringing cold, nutrient-rich water up from the depths, which attracts lots of animals. The dolphin lives in relatively shallow water and mainly eats fish and octopuses that it finds on or near the sea floor.

The Benguela dolphin lives in social groups and sometimes hangs out with other species of dolphin. It doesn’t travel very far throughout the year, barely more than 50 miles, or 80 km. When it hunts for food, it uses very high-pitched navigation clicks that orcas can’t hear, but when it’s in safe areas, socializing without any predators around, it communicates and navigates with lower-pitched sounds. Sharks also sometimes attack it and sometimes humans will catch and eat one, but for the most part, it lives a pretty stress-free life just hanging out with its friends and eating little fish. And that’s basically all we know about this little dolphin.

Alexandra wanted to hear about the spinner dolphin, which is common in warmer waters throughout the world. It’s called the spinner dolphin because it likes to leap into the air, spinning around as it does like an American football, which is pretty spectacular. No one except the spinner dolphin is completely sure why it spins, but scientists speculate it serves more than one purpose. The activity takes a lot of energy, so it might be a way to signal to other dolphins that it’s really strong and fit. The big splash when it lands on its side may be a way to communicate with other dolphins. The action might also help dislodge parasites like remora fish that really do attach themselves to bigger, faster animals to hitch rides and incidentally steal food.

Whatever the reason, the spinner dolphin is one of the most acrobatic dolphins in the world. It not only spins, but it jumps around, flips, slaps its tail on the water, and basically acts like a kid on the first swimming pool visit of the summer. Like most dolphins and whales, it’s a social animal, hanging out with friends, family, and sometimes other dolphin species. It eats small animals like fish, squid, and crustaceans, and at least some populations are nocturnal so they can hunt animals that migrate to shallower water at night.

The spinner dolphin is actually pretty small, growing to not quite 7 feet long at most, or 2.4 meters. It’s mainly dark gray on top, lighter gray on the sides, and pale gray or white on its belly.

Let’s finish with our mystery whale or dolphin, called the Alula whale because it was sighted near the town of Alula, Somalia at some time prior to the early 1970s. In 1971 a Dutch sea captain reported that he had seen these whales on multiple occasions, in the Gulf of Aden and the Indian Ocean. But although it’s a distinctive-sounding whale or dolphin, its existence hasn’t been verified.

Captain Willem Mörzer Bruyns, whose name I have mispronounced, described the Alula whale as being similar in size and shape to the orca or pilot whale, with a tall dorsal fin and rounded forehead. It was sepia brown all over, though, except for white scars all over its body that were shaped sort of like stars. He reported seeing small groups of these whales, anywhere from 4 to 8 of them, traveling together on at least four occasions. He estimated the whales were up to 24 feet long, or 7.2 meters.

There’s quite a bit of confusion about this mystery whale spread across the internet. Some sites I looked at mentioned a book written by Mörzer Bruyns called Field Guide of Whales and Dolphins, published in 1971, but quoted a different book, A World Guide to Whales, Dolphins, and Porpoises published in 1981 by Donald S. Heintzelman.

Let me quote the relevant paragraphs from the 1971 book, the original:

“At first encounter a school of 4 approached the ship head on and seeing the dorsal fins the author thought they were [orcas]. When they passed the ship at a distance of less than 50 yards just under the surface in the flat calm, clear sea, it was obvious that this was a different species. … These dolphins were seen in the area during crossings in April, May, June and September, usually swimming just under the surface with the dorsal fin above the water. One duty officer reported he observed them chasing a school of smaller dolphins, who tried to escape. There is, however, a possibility that both species were chasing the same prey.”

If you go to Wikipedia to read about the Alula whale, as of mid-November 2025, it states that the dorsal fin was about 6 and a half feet tall, or 2 meters. But Mörzer Bruyns reported that the dorsal fin was 2 feet tall, or about 60 cm. That’s an important difference. Orcas, AKA killer whales even though they’re actually big dolphins, are distinctively patterned with black and white, and a male orca can have a dorsal fin up to 6 feet tall, or 1.8 meters, while a female’s is typically less than half that height. The pilot whale is also a dolphin, despite its name, but it has a relatively small dorsal fin and is black, dark gray, or sometimes brown. Some researchers suggest that Mörzer Bruyns misidentified pilot whales as something mysterious, but the details he provided don’t really match up.

There are a lot of little-known whales alive today, some only discovered in the last few decades. It’s possible that the Alula whale really is a very rare small whale or dolphin. It’s not clear from his report, but it sounds like Mörzer Bruyns saw the whales on several occasions in the same year. If so, maybe the Alula whale doesn’t actually live in that part of the ocean most of the time, and Mörzer Bruyns saw the same small group several times that just happened to have traveled to the Indian Ocean that year. Maybe no one else has seen them because they’re all living in some remote part of the ocean where humans seldom travel. Hopefully someone will spot one soon.

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. 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 457: Parrots!

Thanks to Fleur, Yuzu, and Richard from NC for their suggestions this week!

Further reading:

World’s rarest parrot, extinct in wild, hatches at zoo

Kakapo recovery

This Parrot Stood 3 Feet Tall and Ruled the Roost in New Zealand Forests 19 Million Years Ago

The magnificent palm cockatoo:

The gigantic kakapo:

Show transcript:

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

This week we have a bird episode, specifically some interesting parrots. Thanks to Fleur, Yuzu, and Richard from NC for their suggestions!

Parrots are intelligent, social birds that are mostly found in tropical and subtropical parts of the world, but not always. Most parrots eat plant material exclusively, especially seeds, nuts, and fruit, but some species will eat insects and other small animals when they get the chance. Most parrots are brightly colored, but again, not always. And, unfortunately, most parrot species are endangered to some degree due to habitat loss, hunting for their feathers and for the pet trade, and introduced predators like cats and rats.

All parrots have a curved beak that the bird uses to open nuts and seeds, but which also acts as a tool or even a third foot when it’s climbing around in trees. All parrots have strong clawed feet that they also use to climb around and perch in trees, and to handle food and tools.

Let’s start with Yuzu’s suggestions, the cockatoo and the parakeet. A parakeet is a small parrot, but it’s a term that refers to a lot of various types of small parrots. This includes an extinct bird called the Carolina parakeet.

It was small parrot that was common throughout a big part of the United States. It had a yellow and orange head and a green body with some yellow markings, and was about the size of a mourning dove or a passenger pigeon. Its story of extinction mirrors that of the passenger pigeon in many ways. The Carolina parakeet lived in forests and swamps in big, noisy flocks and ate fruit and seeds, but when European settlers moved in, turning forests into farmland and shooting birds that were considered pests, its numbers started to decline. In addition, the bird was frequently captured for sale in the pet trade and hunted for its feathers, which were used to decorate hats.

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

The parakeet Yuzu is probably referencing is the budgie, or budgerigar. It’s the one that’s extremely common as a pet, and it’s native to Australia. In the wild it’s green and yellow with black markings, but the domestic version, which has been bred in captivity since the 1850s, can be all sorts of colors and patterns, including various shades of blue, yellow all over, white, and piebald, meaning the bird has patches of white on its body.

The budgie can learn to repeat words and various sounds, especially if it’s a young bird. I had two parakeets as a kid, named Dandelion and Sky so you can guess their colors, and neither learned to talk although I really tried to teach them. Some birds just aren’t interested in mimicry, while others won’t stop, especially if they get attention when they speak.

In the wild, budgies live in flocks that will travel long distances to find food and water. The birds mostly eat grass seeds, especially spinifex, but will sometimes eat wheat, especially in areas where farmland has destroyed much of their wild food. They’re social birds that are sometimes called lovebirds, although that’s the name of a different type of bird too, because they will preen and feed their mates.

Like many birds, the parakeet can see ultraviolet light, and their feathers glow in UV light. This makes them even more attractive to potential mates, as if the parakeet wasn’t beautiful enough to start with.

Yuzu also asked about the cockatoo. There are 21 species of cockatoo, also native to Australia and other nearby places, including Indonesia and New Guinea. It’s much larger than the budgie and most species have a crest of some kind. It lives in flocks and eats various types of plant material, including flowers and roots, but it will also eat insects. The cockatoo isn’t as brightly colored as many parrots, and is usually black, white, or gray, often with patches of color on the crest, cheeks, or tail.

The pink cockatoo is white with pale salmon pink markings on the body, and brighter pink and yellow on its crest. The sulphur-crested cockatoo is white with pale yellow on the undersides of the wings and tail, and a bright yellow crest. We talked about the palm cockatoo in episode 23 because not only does it look like it should be a drummer of the Muppet Animal variety, since it’s black with red cheeks and a big messy crest, it does actually use sticks and nuts to drum against tree branches, to attract a mate.

Richard from NC suggested we learn about Spix’s macaw, also called the blue macaw, because it’s considered one of the world’s rarest parrots. In fact, it was declared extinct in the wild in 2019. It only survives at all because of intensive conservation efforts, including a captive breeding program spread over multiple zoos.

The blue macaw is native to one small part of Brazil in South America, although it used to be much more common several hundred years ago. It’s blue with a gray-blue head. It’s such a beautiful parrot that it was driven to extinction by people trapping the birds to sell as pets, even though that had been outlawed by Brazil, although its numbers had been falling for centuries due to habitat loss. It relied on a particular species of tree called the tree of gold, because its flowers are bright yellow. The blue macaw nested in these trees, and its seedpods were one of its main foods. As groves made up of the tree of gold were chopped down to make way for farmland and towns, the bird became more and more rare.

Luckily, even though the blue macaw doesn’t breed very quickly in captivity, by 2022 there were enough healthy young birds to release twenty into the wild. Just a few weeks ago as this episode goes live, another egg has hatched in captivity in a bird conservation center in Belgium, after the previous hundred eggs were infertile and never hatched.

Next, Fleur wanted to learn more about the kakapo, a flightless, nocturnal parrot that lives only in New Zealand. We talked about it in episode 313, but it’s definitely time to revisit it.

The kakapo is the largest living parrot. It has green feathers with speckled markings, blue-gray feet, and discs of feathers around its eyes that make its face look a little like an owl’s face. That’s why it’s sometimes called the owl parrot. Males are almost twice the size of females on average. It can grow over two feet long, or 64 cm, and can weigh as much as 9 lbs, or about 4 kg. That’s way too heavy for it to fly, but its legs are short but strong and it will jog for long distances to find food. It can also climb really well, right up into the very tops of trees. It uses its strong legs and its large curved bill to climb. Then, to get down from the treetop more efficiently, the kakapo will spread its wings and parachute down, although its wings aren’t big enough or strong enough for it to actually fly. A big heavy male sort of falls in a controlled plummet while a small female will land more gracefully.

The kakapo evolved on New Zealand where it had almost no predators. A few types of eagle hunted it during the day, which is why it evolved to be mostly nocturnal. Its only real predator at night was one type of owl. As a result, the kakapo was one of the most common birds throughout New Zealand when humans arrived.

But by the end of the 19th century, the kakapo was becoming increasingly rare everywhere. By 1970, scientists worried that the kakapo was already extinct. Fortunately, a few of the birds survived in remote areas. Several islands were chosen as refuges, and all the kakapos scientists could find were relocated to the islands, 65 birds in total. While the kakapo is doing a lot better now than it has in decades, it’s still critically endangered. The current population is 237 individuals according to New Zealand’s Department of Conservation.

The kakapo may be the largest living parrot, but it’s not the largest parrot that ever lived. That would be the giant parrot. It’s known only from a few fossils dated to between 16 and 19 million years ago, but from those fossils scientists estimate that the giant parrot grew around 3 feet tall, or almost a meter, and possibly weighed almost twice what the kakapo weighs. It’s the largest parrot that ever lived as far as we know, and it was probably related to the kakapo.

We don’t know a lot about the giant parrot because only two fossils have been found, both of them leg bones and probably from the same individual. They bones are so big that scientists initially thought they belonged to an eagle. Hopefully soon more fossils will come to light so we can learn more about the giant parrot. For all we know, those leg bones belonged to a young parrot that wasn’t fully grown yet. Maybe the adults were even bigger than we think!

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. 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 454: Bats!

This week we’re going to learn about a bunch of bats! Thanks to John, Murilo, and Alexandra for their suggestions!

Further reading:

Why Bats Can’t Walk: The Evolutionary Lock That Keeps Them Flying

On a Wing and a Song—Bats Belt out High-Pitched Tunes to Woo Mates

Why some bats hunt during the day

Puzzling Proto-Bats

A pekapeka just walking around catching bugs on the ground [photo by Rod Morris, from link above]:

BLOOOOOOD! but a really cute smile too:

The western red bat looks ready for Halloween!

Show transcript:

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

This week as monster month continues, we’re going to learn about bats! We’ve talked about bats in lots of previous episodes, but we have a lot of really neat information in this one that we’ve never covered before. Thanks to John, Alexandra, and Murilo for their suggestions!

John suggested we learn about diurnal bats and also asked if there are any flightless bats, maybe ones that live on islands. There are lots of island-living bats, and many birds that live on islands evolve to be flightless. It makes sense that bats might do the same thing–but I couldn’t find any information about any known bat that has lost the ability to fly.

The reason seems to be how highly derived bats are. That means they’re specialized, the only mammal known that has ever evolved true flight. Unlike birds, which don’t need to use their legs when flying, bats’ legs are actually part of the wings. The wing membranes, called patagia, stretch not just between the elongated finger bones of the bat’s hands, they also stretch between the arms and legs, and connect the legs too.

A January 2025 study comparing bat skeletons to the skeletons of birds determined that unlike in birds, where the size of the legs doesn’t have anything to do with the size of the wings, in bats the leg size and the wing size are closely related. If a bat evolves smaller wings, its legs also evolve to become smaller. That’s why there are no bats that resemble ostriches, with tiny wings but really long legs.

Another possible reason is that bat legs have evolved to point backwards compared to other animals. It’s not just the feet, the knees are also rotated backwards. That’s why bats hang upside-down when they’re not flying. Many species of bat never land on the ground, because they literally can’t walk at all.

But there are a few species of bats that can walk quite well. One is the increasingly threatened New Zealand lesser short-tailed bat. It lives in a few places in both the North and South Islands, as well as some small islands off the coast, although it used to be much more widespread. It’s also called by its Maori name, the pekapeka.

The pekapeka mainly lives in forested areas and is quite small. It’s brown with a lighter belly, and it has big ears, as do most bats. Its eyes are small and its vision isn’t very good, but it has a good sense of smell. Its wings are small so its legs are correspondingly small too, but its legs are also strong despite their size. It has a clawed thumb toe on its feet and on its wings that helps it climb around in trees when it needs to, and it also spends about half of its time on the ground. It walks just fine, crawling with its wings folded so that the ends point up and back, out of the way. And yes, its legs are rotated backwards as you’d expect in a bat, and it roosts by hanging from its feet in trees.

The pekapeka flies normally and catches insects using echolocation, just like other microbats throughout the world. It especially likes moths. Unlike almost all other bats, it finds a lot of its food on the ground too, using its sense of smell to track down spiders, insects and larvae, and other small invertebrates. It will actually dig into the dirt and leaf litter to find food. It also eats nectar and flowers, and is an important pollinator of some plants.

One great thing about the pekapeka is that the males sing to attract a mate. The sound is so high-pitched that it’s not practical to share it here, because you probably wouldn’t be able to hear it, but I’ll link to an article that has a sample bat song so you can listen.

Another bat that can walk just fine is one suggested by Murilo, the vampire bat. In movies, vampire bats are usually depicted as being humongous, as big as a person! In reality, those big bats are actually megabats, and megabats mostly eat fruit. Megabats are the ones that are sometimes called sky puppies, because they don’t rely very much on echolocation so they don’t have the complicated ears and noses that microbats do. Until recently scientists thought megabats couldn’t echolocate at all, but now we know they can, they’re just not all that good at it. The vampire bat is tiny in comparison.

There are three species of vampire bat alive today. They share the same subfamily, Desmodontinae, but have been classified in different genera because they differ considerably from each other. Their other relations are ordinary bats that eat insects, fruit, and other things that you’d expect from bats. Vampire bats really do eat blood exclusively.

The hairy-legged vampire bat is the most basal of the three species, meaning it retains traits that haven’t changed as much from its ancestors. It feeds exclusively on bird blood. The white-winged vampire bat also mostly feeds on bird blood, but it will sometimes eat the blood of mammals. It’s the common vampire bat that eats the blood of mammals.

Vampire bats probably evolved from ancestors that ate insects. Scientists hypothesize that they might have originally specialized in eating ectoparasites of other animals, or possibly insects that were attracted to animal wounds. If that’s the case, the bat would have already been eating a lot of blood along with the insects, and at some point it started taking a shortcut to getting that yummy blood. We know this has happened at least one other time, in a bird.

I thought we had talked about the red-billed oxpecker in an old episode, but if we did, I couldn’t find it. It lives throughout the savannas of sub-Saharan Africa and is brown with a bright orange bill and eyes, with a yellow eye ring. It eats ticks that it picks off rhinoceroses, cattle, and other large mammals, but it actually mainly eats blood. It’s happy to eat the ticks, because they’re full of blood, and the animals it perches on are happy that it eats ticks, but the bird will also peck at wounds so it can drink blood directly from the animal.

So it’s likely that the vampire bat started out eating ticks or other ectoparasites, then began eating the blood that oozed from the wound after it removed a tick. From there it was a short step to biting the animal to cause blood to flow, and within four million years, it was fully adapted to drinking blood.

The vampire bat has extremely sharp front teeth that stick out so that it can use them to make little cuts in an animal’s skin, after first using its teeth to shave the fur down so it can reach the skin more easily. Its fangs lack enamel, so they stay razor sharp. The vampire bat’s saliva contains anticoagulants, so the blood won’t clot right away and the bat can lick it up until it’s full, which takes about 20 minutes. It digests blood extremely quickly, so that it absorbs the nutrients from the blood and starts urinating the extra liquid within a few minutes of starting to feed. That way it can eat more and it can also stay light enough to take flight if it’s disturbed. If you were wondering, its poop is the same as other bat poop. It does echolocate, although not as expertly as bats that eat insects, but the common vampire bat also has specialized thermoreceptors on its nose that sense heat. It’s the only mammal known that can detect infrared radiation, and the only other vertebrates known that can do the same thing are some snakes.

Because vampire bats have to be able to walk around on animals to find a good spot to bite them, the bats have evolved to be able to walk, run, and even jump just fine. Like the pekapeka, it folds the ends of its wings back out of the way and basically walks on the wrists of its wings and its backwards-pointing feet.

Even though the pekapeka and the vampire bat are comfortable running around on the ground, neither has lost the ability to fly. Being able to fly seems to be baked into being a bat. So while it’s not impossible that a bat might eventually become truly flightless, it’s unlikely.

As for bats that are diurnal, or daytime bats, there are a few. A study published in 2018 determined that of the four known species of bat that routinely go out hunting during the daytime, all four live on islands where there are no predatory birds. That doesn’t mean that all bats that live in places where there aren’t any hawks or eagles or crows are active during the day, because most species are still nocturnal, but that seems to be the one requirement for a daytime bat.

John was also interested in learning about the biggest fossil bat ever found. Bats are delicate creatures and don’t fossilize very well, so the bat fossil record is really fragmentary. For example, until 2015 the oldest pekapeka fossil discovered was only 17,500 years old. In 2015, a new fossilized pekapeka ancestor was discovered on the South Island that’s been dated to 16 to 19 million years ago. The fossil shows that the bat was adapted to walk just as the modern pekapeka is, and its teeth are similar so it probably had a similar diet—but it’s estimated to be three times the size of the pekapeka! That sounds like it must have been a huge bat, but the pekapeka only weighs 15 grams at most. That’s barely more than half an ounce, or about the same weight as a CD or DVD, not counting the case. Its ancestor is estimated to have weighed as much as 40 grams, which is almost as heavy as a golf ball. It’s also what a typical vampire bat weighs, if you were wondering.

An even bigger fossil bat has been discovered in a fossil site in France, a country in Europe, and another in Tunisia, a country in North Africa. It’s called Necromantis and is estimated to have weighed as much as 47 grams, which is the same weight as two mice. Two nervous mice, because Mecromantis had strong jaws and big teeth, which suggests it ate small vertebrates–like mice. It lived between 44 and 36 million years ago in areas that were most likely tropical.

An ancestor of the vampire bat was even bigger, possibly as much as 60 grams. That’s just over 2 ounces! That’s a bit heavier than a tennis ball. It lived in South America during the Pleistocene, so recently that in addition to fossils, we also have subfossil remains. That means they’re mineralized but not yet fully fossilized. It’s called Desmodus draculae, and it was most likely still around when humans migrated to South America around 25,000 years ago. Big as it was, it still wasn’t as big as a typical megabat.

Because bat fossils are so rare, it’s led to a scientific mystery. We don’t have any fossils of bat ancestors that weren’t yet bats, but were evolving into bats. In other words, we don’t know what bats looked like before they evolved to be flying animals. The best guess is that the earliest bat ancestors were shrew-like animals that lived in trees and ate insects.

So far we haven’t mentioned any bats that live in Arizona, suggested by Alexandra, so let’s learn about the western red bat. Most bats are black, gray, or brown in color, but the western red bat is a cheerful orange with white shoulder patches and black wing membranes. It’s ready for Halloween all the time! Males are usually more brightly colored than females.

The western red bat lives throughout western North America in summer. It migrates to the southern parts of its range in winter, as far south as Central America. It’s also called the desert red bat but it actually spends most of its life in forests, where its red coat blends in with dead leaves. It eats insects and while it doesn’t spend much time on the ground, every so often it will drop to the ground to catch an insect before hopping back into the air. Not only that, but when the western red bat migrates, it will sometimes fly along with flocks of migrating birds in the daytime.

Unlike many bats, the western red bat is solitary most of the year. Also unlike most bats, instead of having just one baby at a time, it can have up to four babies in a litter. The mother has four nipples instead of just two as in most bats, and for the first three or four weeks of the babies’ lives, the mother has to carry them around while she hunts, until they learn to fly.

As a last note about bats, Murilo specifically mentioned that vampire bats carry diseases that humans can catch. (If diseases bother you, you can stop listening now because we’re almost done.) The common vampire bat does occasionally bite humans, usually the bare big toe of someone sleeping outside, or sometimes the earlobe or even the nose. Vampire bats do show a lot of resistance to blood-borne diseases, but they still spread diseases. The best way to avoid catching a disease from a vampire bat is to not sleep outside without shelter if you can avoid it, if you’re in an area of South America where vampire bats live. That means that if you’re out camping, bring a tent even if it’s hot. Also, avoid eating the meat of wild boar from South America. Not only can boars catch diseases from vampire bats that they pass on to humans, but wild boars also eat fruit partially eaten by fruit bats that also carry diseases. The fruit bats drop partially eaten fruit, the wild boar eats the fruit along with the saliva left on it by the bat, and then the boar can get sick from the saliva.

Most mammals can catch rabies. If you see a bat out in the daytime crawling on the ground, don’t assume that you’re seeing a very rare daytime bat that can also walk around like a pekapeka. Leave the bat alone and contact animal control, because most likely the poor bat has contracted rabies. If you touch the bat, even if it doesn’t bite you, you will have to get a series of rabies vaccines to make sure you don’t come down with rabies, which is an incurable disease and always fatal. That is way scarier than anything else we’ve ever talked about on monster month episodes!

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. 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 450: Geckos and the Snow Leopard

Thanks for Preston and Pranav for suggesting this week’s topics!

Further reading:

DNA has revealed the origin of this giant ‘mystery’ gecko

Snow Leopards Dispersed Out of Tibetan Plateau Multiple Times, Researchers Say

Conquest of Asia and Europe by snow leopards during the last Ice Ages uncovered

The crested gecko AKA the eyelash gecko:

The fluffy snow leopard:

Show transcript:

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

This week we have a couple of suggestions from Preston and one from Pranav! This is the first episode I’ve recorded in my new apartment, so let’s make it a good one.

First, Preston wanted to learn more about the crested gecko, mainly because he has a pet crested gecko named George Washington. That is one of the best gecko names ever!

The crested gecko is also called the eyelash gecko. We’ve talked about it a few times, but not recently at all. It’s native to a collection of remote Pacific islands called New Caledonia, where it spends most of its time in trees, eating insects and other small animals, but also fruit, nectar, and lots of other food. It’s an omnivore and nocturnal, and can grow more than 10 inches long, or 25 cm. It gets its names from the tiny spines above its eyes that look like eyelashes, and more spines in two rows down its back, like a tiny dragon. It can be brown, reddish, orange, yellow, or gray, with various colored spots, which has made it a popular pet. These days all pet crested geckos were bred in captivity, since it’s now protected in the wild.

The crested gecko has tiny claws on its toes, which is unusual since most geckos don’t have claws. It can drop its tail like other geckos if a predator is after it, but the tail doesn’t grow back. Since its tail is prehensile and helps it climb around in trees, you’d think the gecko would have trouble climbing after it loses its tail, but it doesn’t. Maybe that’s because in addition to claws, like other geckos it has basically microscopic hairlike structures on its toes that allow it to climb smooth surfaces like windows and walls and the trunks of smooth trees. It can also jump long distances to get to a new branch.

The crested gecko was discovered by science in 1866, but wasn’t seen after that in so long that people thought it was extinct. Then in 1994, a German herpetologist out looking for specimens after a tropical storm found a single crested gecko. It turns out that the geckos had been fine all along, but because they’re nocturnal and mostly live in trees, scientists just hadn’t spotted any.

While we’re talking about geckos, Pranav requested that we revisit Delcourt’s giant gecko with some updated information. We did mention the new findings back in episode 389, but it’s really interesting so let’s go over it again.

Way back in episode 20 we talked about Delcourt’s giant gecko, which is only known from a single museum specimen donated in the 19th century. In 1979 a herpetologist named Alain Delcourt, working in the Marseilles Natural History Museum in France, noticed a big taxidermied lizard in storage and wondered what it was. It wasn’t labeled and he didn’t recognize it, surprising since it was the biggest gecko he’d ever seen—two feet long, or about 60 cm. He sent photos to several reptile experts and they didn’t know what it was either. Finally the specimen was examined and in 1986 it was described as a new species.

No one knew anything about the stuffed specimen, including where it was caught. At first researchers thought it might be from New Caledonia since a lot of the museum’s other specimens were collected from the Pacific Islands. None of the specimens donated between 1833 and 1869 had any documentation, so it seemed probable the giant gecko was donated during that time and probably collected not long before. More recently there was speculation that it was actually from New Zealand, since it matched Maori lore about a big lizard called the kawekaweau.

In June of 2023, Delcourt’s gecko was finally genetically tested and determined to belong to a group of geckos from New Caledonia, the same archipelago of islands where the crested gecko is from. Many of its close relations are large, although not as large as it is. It’s now been placed into its own genus.

Of course, this means that Delcourt’s gecko isn’t the identity of the kawekaweau, since it isn’t very closely related to the geckos of New Zealand, but it might mean the gecko still survives in remote parts of New Caledonia. It was probably nocturnal and lived in trees, hunting birds, lizards, and other small animals.

Now we’re done with geckos for today, but we’re not done with this episode! Preston also wanted to learn about the snow leopard, and it’s amazing that we’ve never talked about it before! The snow leopard is a big cat that’s most closely related to the tiger, although they don’t look very much alike. The term big cat refers to tigers, lions, leopards, snow leopards, and jaguars, but it can also include cheetahs and cougars depending on who you ask. Big cats have round pupils instead of slit pupils like domestic cats and other smaller cats.

The snow leopard mostly lives in cold, mountainous areas in parts of Asia, from Siberia to India. It prefers to live in rocky areas where its coat pattern hides it from its prey. Its fur is thick and it can be anywhere from pure white to tan or gray, with black spots and rosettes. Its head is small, its legs relatively short, and its tail is very fluffy and incredibly long. A big male can grow up to 1.5 meters long, or 5 feet, plus a tail that’s almost as long as his body, but he’s only about two feet tall at the shoulder, or not quite 60 cm.

The snow leopard is well adapted to cold and snow. Fur grows on the underside of its paws to keep its feet warm, its paws are really large to act as snowshoes, and its ears are small and rounded to keep the tips from being frostbitten. Its long tail helps it balance when climbing over rocks. Its tail also stores fat, and is so long and fluffy that the snow leopard can use its tail as a blanket when it’s sleeping. Built-in blanket!

Unfortunately for the snow leopard, its thick, beautiful fur has been used as a blanket by humans for a long time, and it’s still sometimes killed for its fur even though it’s a protected species almost everywhere it lives. It’s also sometimes killed by farmers and herders who think the snow leopard will kill their livestock. It actually doesn’t attack livestock very often, and almost never attacks people. It eats small animals of various kinds depending on where it lives, like mice and rats, hares and rabbits, wild goats and sheep, marmots, deer, civets, and even rhesus macaques. It mainly only kills livestock where its wild prey has been reduced because of human activity. It’s also vulnerable to habitat loss and climate change.

Snow leopards are mostly solitary, although a mated pair will hunt together and of course the mother snow leopard teaches her babies to hunt as they get older. Individuals leave scent marks and spray urine to let other snow leopards know they’re around. Males roam widely but females usually stay to a territory that they’re familiar with, although the territory may be quite large.

Most snow leopard cubs are born in the early summer, and a female usually only has two or three babies in a litter. The mother takes care of her babies by herself. She makes a den among rocks and lines it with her belly fur, but cubs are born with a lot of fur already to keep them warm. The mother takes care of them for about two years until they finally leave to find their own territories.

Lions, tigers, leopards, and jaguars can all roar. Snow leopards, cheetahs, and cougars can’t. But snow leopards, cheetahs, and cougars can purr, while lions, tigers, leopards, and jaguars can’t. The ability to roar is due to special adaptations in the larynx, but these adaptations also mean the animal can’t purr. So basically a cat can either roar or purr but not both and the snow leopard can purr.

We actually don’t know a whole lot about the snow leopard because it lives in such remote places, and one big mystery is how the snow leopard ended up adapted to cold. Most cats, large and small, prefer hot climates. Until recently, we didn’t even have any snow leopard fossils to give us a clue.

Then a collection of leopard fossils revealed some snow leopard fossils mixed in. They’re about a million years old, collected in parts of China, France, and Portugal. A study of the fossils, and a beautifully preserved partial skeleton found in Portugal, has shed light on the migration and evolution of the snow leopard.

The snow leopard was already well adapted for mountainous areas, but when the climate became colder during the Pleistocene, AKA the Ice Age, it evolved to thrive in a cold climate. It spread into many parts of Asia and Europe, especially mountainous areas, out-competing other predators like leopards that weren’t well adapted to cold. With the warming climate after the ice ages ended, the snow leopard was at a disadvantage and gradually died out except around the Tibetan plateau where it still lives today, and we’re very lucky to still have it.

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. 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 447: So Many Legs!

Thanks to Mila for suggesting one of our topics today!

Further reading:

The mystery of the ‘missing’ giant millipede

Never-before-seen head of prehistoric, car-size ‘millipede’ solves evolutionary mystery

A centipede compared to a millipede:

Show transcript:

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

Let’s finish invertebrate August this year with two arthropods. One is a suggestion from Mila and the other is a scientific mystery that was solved by a recent discovery, at least partially.

Mila suggested we learn about centipedes, and the last time we talked about those animals was in episode 100. That’s because centipedes are supposed to have 100 legs.

But do centipedes actually have 100 legs? They don’t. Different species of centipede have different numbers of legs, from only 30 to something like 300. Like other arthropods, the centipede has to molt its exoskeleton to grow larger. When it does, some species grow more segments and legs. Others hatch with all the segments and legs they’ll ever have.

A centipede’s body is flattened and made up of segments, a different number of segments depending on the centipede’s species, but at least 15. Each segment has a pair of legs except for the last two, which have no legs. The first segment’s legs project forward and end in sharp claws with venom glands. These legs are called forcipules, and they actually look like pincers. No other animal has forcipules, only centipedes. The centipede uses its forcipules to capture and hold prey, and to defend itself from potential predators. A centipede pinch can be painful but not dangerous unless you’re also allergic to bees, in which case you might have an allergic reaction to a big centipede’s venom. Small centipedes can’t pinch hard enough to break a human’s skin.

A centipede’s last pair of legs points backwards and sometimes look like tail stingers, but they’re just modified legs that act as sensory antennae. Each pair of a centipede’s legs is a little longer than the pair in front of it, which helps keep the legs from bumping into each other when the centipede walks.

The centipede lives throughout the world, even in the Arctic and in deserts, but it needs a moist environment so it won’t dry out. It likes rotten wood, leaf litter, soil, especially soil under stones, and basements. Some centipedes have no eyes at all, many have eyes that can only sense light and dark, and some have relatively sophisticated compound eyes. Most centipedes are nocturnal.

The largest centipedes alive today belong to the genus Scolopendra. This genus includes the Amazonian giant centipede, which can grow over a foot long, or 30 cm. It’s reddish or black with yellow bands on the legs, and lives in parts of South America and the Caribbean. It eats insects, spiders–including tarantulas, frogs and other amphibians, small snakes and lizards, birds, and small mammals like mice. It’s even been known to catch bats in midair by hanging down from cave ceilings and grabbing the bat as it flies by.

Some people think that the Amazonian giant centipede is the longest in the world, but this isn’t actually the case. Its close relation, the Galapagos centipede, can grow 17 inches long, or 43 cm, and is black with red legs.

But if you think that’s big, wait until you hear about the other animal we’re discussing today. It’s called Arthropleura and it lived in what is now Europe and North America between about 344 and 292 million years ago.

Before we talk about it, though, we need to learn a little about the millipede. Millipedes are related to centipedes and share a lot of physical characteristics, like a segmented body and a lot of legs. The word millipede means one thousand feet, but millipedes can have anywhere from 36 to 1,306 legs. That is a lot of legs. It’s probably too many legs. The millipede with 1,306 legs is Eumillipes persephone, found in western Australia and only described in 2021. It lives deep underground in forested areas, where it probably eats fungus that grows on tree roots. It’s long and thin with short legs and no eyes. It’s only about 1 mm in diameter, but can grow nearly 4 inches long, or almost 10 cm.

Millipedes mostly eat decaying plant material and are generally chunkier-looking than centipedes. They have two pairs of legs per segment instead of just one, with the legs attached on the underside of the segment instead of on the sides. A millipede usually has short, strong antennae that it uses to poke around in soil and decaying leaves. It can’t pinch, sting, or bite, although some species can secrete a toxic liquid that also smells terrible. Mostly if it feels threatened, a millipede will curl up and hope the potential predator will leave it alone.

The biggest millipede alive today is probably the giant African millipede, which can grow over 13 inches long, or almost 34 cm, but because millipedes are common throughout the world and are often hard for scientists to find, there may very well be much larger millipedes out there that we just don’t know about.

As an example, in 1897 scientists discovered a new species of giant millipede in Madagascar and named it Spirostreptus sculptus. One specimen found was almost 11 inches long, or over 27 cm. But after that, no scientist saw the millipede again—until 2023, when a scientific expedition looking for lost species rediscovered it, along with 20 other species of animal. It turns out that the millipede isn’t even uncommon in the area, so the local people probably knew all about it.

But Arthropleura was way bigger than any millipede or centipede alive today. It could grow at least 8 ½ feet long, or 2.6 meters, and possibly longer. It probably weighed over 100 lbs, or 45 kg. We have plenty of fossilized specimens, but not one of them has an intact head. Then scientists discovered two beautifully preserved juvenile specimens in France, and CT scans in 2024 revealed that both specimens had nearly complete heads.

The big question about Arthropleura was whether it was more closely related to millipedes or centipedes, or if it was something very different. Without a head to study, no one could answer that question with any confidence, although a lot of scientists had definite opinions one way or another. Studies of the head scans determined that Arthropleura was indeed more closely related to modern millipedes—but naturally, since it lived so long ago, it also had a lot of traits more common in centipedes today. It also had something not found in either animal, eyes on little stalks.

There are still lots of mysteries surrounding Arthropleura. For instance, what did it eat? Because of its size, scientists initially thought it might be a predator. Now that we know it was more closely related to the millipede than the centipede, scientists think it might have eaten like a millipede too. That would mean it mostly ate decaying vegetation, but we don’t know for sure. We also don’t know if it could swim or not. We have a lot of Arthropleura tracks that seem to be made along the water’s edge, so some scientists hypothesize that it could swim or at least spent part of its time in the water. Other scientists point out that Arthropleura didn’t have gills or any other way to absorb oxygen while in the water, so it was more likely to be fully terrestrial. The first set of scientists sometimes comes back and argues that we don’t actually know how Arthropleura breathed or even why it was able to grow so large, and maybe it really did have gills. A third group of scientists then has to come in and say, hey, everyone calm down, maybe the next specimen we find will show evidence of both lungs and gills, and it spent part of its time on land and part in shallow water, so there’s no need to argue. And then they all go for pizza and remember that they really love arthropods, and isn’t Arthropleura the coolest arthropod of all?

At least, I think that’s how it works among scientists. And Arthropleura is really cool.

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. 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 444: Diskagma and Horodyskia

It’s Invertebrate August! These creatures are the most invertebrate-y of all!

Further reading:

Dubious Diskagma

Horodyskia is among the oldest multicellular macroorganisms, finds study

A painting of diskagma, taken from the top link above:

Little brown jug flowers (not related to diskagma in any way!):

Show transcript:

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

This episode started out as the March 2025 Patreon episode, but there was more I wanted to add to it that I didn’t have time to cover in that one. Here’s the expanded version to kick off Invertebrate August, which also happens to be episode 444 and releasing on August 4th! It’s about two mystery fossils.

The first is named Diskagma, which means disc-shaped fragment, and it was only described in 2013. That’s partly because it’s so small, barely two millimeters long at most, and partly because of where it’s found. That would be fossilized in extremely old rocks.

When I saw the illustration accompanying the blog post where I learned about Diskagma, I thought it was a cluster of cup-like flowers, sort of like the flowers of the plant called little brown jug. I was ready to send the link to Meredith Hemphill of the Herbarium of the Bizarre podcast, which by the way you should be listening to. But then I saw how old Diskagma is.

It’s been dated to 2.2 billion years old. That’s older than any plant, probably by as much as a billion years.

Even more astounding, it lived on land.

As a reminder, the Cambrian explosion took place about half a billion years ago, when tiny marine animals diversified rapidly to fill new ecological niches. That happened in the water, though, mainly in shallow, warm oceans. If you go back to around 850 million years ago, that may have been roughly the time that land plants evolved from green algae that lived in fresh water. Plant-like algae, or possibly algae-like plants, might be as old as 1 billion years old. But before then, scientists don’t find evidence of anything except microbes living on land, and they were probably restricted to lakes and other bodies of fresh water. That’s because there wasn’t much soil, just broken-up rock that contained very few nutrients and couldn’t retain much water.

Diskagma was shaped like a tiny elongated cup, or an urn or vase, with what looks like a stem on one end and what looks like an opening at the other end. The opening contained structures that look like little filaments, but the filaments didn’t fill the whole cup. Most of the cup was diskagma’s body, so to speak, although we don’t know what it contained. We also don’t know what the filaments were for. We do know that the stem actually did connect diskagma to other cups, so that they lived in little groups. We don’t know if it was a single animal with multiple cuplike structures or if it was a colony, or really anything.

That’s the problem. We don’t know anything about diskagma except that it existed, and that it lived on land 2.2 billion years ago. Tiny as it was, though, it wasn’t microscopic, and it definitely appears more complex than would be expected that long ago, especially from something living on dry land.

One suggestion is that the main part of its body contained a symbiotic bacteria that could convert chemicals to nutrients. As in many modern animals, especially extremophiles, the bacteria would have had a safe place to live and the diskagma would have had nutrients that allowed it to live without needing to eat.

Diskagma lived at an interesting time in the earth’s history, called the great oxygenation event, also called the great oxidation event. We talked about it in episode 341 in conjunction with cyanobacteria, because cyanobacteria basically started the great oxygenation event. Cyanobacteria are still around, by the way, and are doing just fine. They’re usually called blue-green algae even though they’re not actually algae.

Cyanobacteria photosynthesize, and they’ve been doing so for far longer than plants–possibly as much as 2.7 billion years, although scientists think cyanobacteria originally evolved around 3.5 billion years ago. The earth is about 4.5 billion years old, if you were wondering.

Like most plants also do, cyanobacteria produce oxygen as part of the photosynthetic process, and when they started doing so around 2.7 billion years ago, they changed the entire world. Before then, earth’s atmosphere hardly contained any oxygen. If you had a time machine and went back to more than two billion years ago, and you forgot to bring an oxygen tank, you’d instantly suffocate trying to breathe the air. But back then, even though animals and plants didn’t yet exist, the world contained a whole lot of microbial life, and none of it wanted anything to do with oxygen. Oxygen was toxic to the lifeforms that lived then, but cyanobacteria just kept producing it.

Cyanobacteria are tiny, but there were a lot of them. Over the course of about 700 million years, the oxygen added up until other lifeforms started to go extinct, poisoned by all that oxygen in the oceans and air. By two billion years ago, pretty much every lifeform that couldn’t evolve to use or at least tolerate oxygen had gone extinct.

Since Diskagma lived during the time of the great oxygenation event, some scientists suggest that it contained microbes that photosynthesized sunlight into nutrients diskagma could use. And, as in cyanobacteria, the side effect of photosynthesis is oxygen, so diskagma might have been contributing to the oxygen in the air that allows us to breathe these days. On the other hand, it might not have had anything to do with photosynthesis and the great oxygenation event might have driven diskagma to extinction. We have no way to know right now.

What we do know is that 700 million years after diskagma lived, something similar appears in the fossil record. It’s called Horodyskia and its fossils have been found in rocks dating between 1.5 billion years ago to 550 million years ago. Unlike diskagma, which has only been found in rocks from South Africa, horodyskia fossils have been found in Australia, China, and North America. That doesn’t mean diskagma wasn’t widespread, just that we haven’t found it anywhere else. There aren’t all that many rocks that are over two billion years old.

Horodyskia lived in the water, specifically at the bottom of the ocean, probably in shallow water. It’s been described as looking like a row of beads on a thread. The thread seemed to be buried in the sand, and growing up from it in intervals were little pear-shaped bulbs, each no larger than a millimeter long, that stuck up through the sand into the water. There may have been little root-like structures called holdfasts that grew from the bottom of the thread to help keep it in place.

We don’t know a lot about horodyskia either. It wasn’t a plant, since it also lived long before plants evolved. A 2023 study determined that it was a multicellular creature and that it was most likely a protist. Protists are related to animals, plants, and fungi, but aren’t any of those things, and they’re an incredibly diverse group. Most are single-celled and microscopic, but not always. They include algae, amoebas, slime molds, and lots more. Horodyskia’s bulbs might have been encased in a jelly-like substance, as is common in a lot of protists. Some horodyskia specimens found in younger rocks, the ones about 550 million years old, are much smaller than the earlier specimens, with each bulb barely a fraction of a millimeter in size.

We might not know much about these strange life forms, but knowing they existed tells us that even two billion years ago, life was a lot more varied than we used to think. And that’s the most exciting thing of all.

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. 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 442: Trees and Megafauna

Further reading:

The Trees That Miss the Mammoths

The disappearance of mastodons still threatens the native forests of South America

Study reveals ancient link between mammoth dung and pumpkin pie

A mammoth, probably about to eat something:

The Osage orange fruit looks like a little green brain:

Show transcript:

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

Way back at the end of 2017, I found an article called “The Trees That Miss the Mammoths,” and made a Patreon episode about it. In episode 320, about elephants, which released in March of 2023, I cited a similar article connecting mammoths and other plants. Now there’s even more evidence that extinct megafauna and living plants are connected, so let’s have a full episode all about it.

Let’s start with the Kentucky coffeetree, which currently only survives in cultivation and in wetlands in parts of North America. It grows up to 70 feet high, or 21 meters, and produces leathery seed pods so tough that most animals literally can’t chew through them to get to the seeds. Its seed coating is so thick that water can’t penetrate it unless it’s been abraded considerably. Researchers are pretty sure the seed pods were eaten by mastodons and mammoths. Once the seeds traveled through a mammoth’s digestive system, they were nicely abraded and ready to sprout in a pile of dung.

There are five species of coffeetree, and the Kentucky coffeetree is the only one found in North America. The others are native to Asia, but a close relation grows in parts of Africa. It has similar tough seeds, which are eaten and spread by elephants.

The African forest elephant is incredibly important as a seed disperser. At least 14 species of tree need the elephant to eat their fruit in order for the seeds to sprout at all. If the forest elephant goes extinct, the trees will too.

When the North American mammoths went extinct, something similar happened. Mammoths and other megafauna co-evolved with many plants and trees to disperse their seeds, and in return the animals got to eat some yummy fruit. But when the mammoths went extinct, many plant seeds couldn’t germinate since there were no mammoths to eat the fruit and poop out the seeds. Some of these plants survive but have declined severely, like the Osage orange.

The Osage orange grows about 50 or 60 feet tall, or 15 to 18 meters, and produces big yellowish-green fruits that look like round greenish brains. Although it’s related to the mulberry, you wouldn’t be able to guess that from the fruit. The fruit drops from the tree and usually just sits there and rots. Some animals will eat it, especially cattle, but it’s not highly sought after by anything. Not anymore. In 1804, when the tree was first described by Europeans, it only grew in a few small areas in and near Texas. The tree mostly survives today because the plant can clone itself by sending up fresh sprouts from old roots.

But 10,000 years ago, the tree grew throughout North America, as far north as Ontario, Canada, and there were seven different species instead of just the one we have today. 10,000 years ago is about the time that much of the megafauna of North and South America went extinct, including mammoths, mastodons, giant ground sloths, elephant-like animals called gomphotheres, camels, and many, many others.

The osage orange tree’s thorns are too widely spaced to deter deer, but would have made a mammoth think twice before grabbing at the branches with its trunk. The thorns also grow much higher than deer can browse. Trees that bear thorns generally don’t grow them in the upper branches. There’s no point in wasting energy growing thorns where nothing is going to eat the leaves anyway. If there are thorns beyond reach of existing browsers, the tree must have evolved when something with a taller reach liked to eat its leaves.

The term “evolutionary anachronism” is used to describe aspects of a plant, like the Osage orange’s thorns and fruit, that evolved due to pressures of animals that are now extinct. Scientists have observed evolutionary anachronism plants throughout the world. For instance, the lady apple tree, which grows in northern Australia and parts of New Guinea. It can grow up to 66 feet tall, or 20 meters, and produces an edible red fruit with a single large seed. It’s a common tree these days, probably because the Aboriginal people ate the fruit, but before that, a bird called genyornis was probably the main seed disperser of the lady apple.

In episode 217 we talked about the genyornis, a flightless Australian bird that went extinct around 50,000 years ago but possibly more recently. It grew around 7 feet tall, or over 2 meters, and recent studies suggest it ate a lot of water plants. It would have probably eaten the lady apple fruit whenever it could, most likely swallowing the fruits whole and pooping the big seeds out later.

Way back in episode 19 we talked about a tree on the island of Mauritius that relied on the dodo’s digestive system to abrade its seeds so they could sprout. It turns out that study was flawed and the seeds don’t need to be abraded to sprout. They just need an animal to eat the flesh off the seed, either by just eating the fruit and leaving the seed behind, or by swallowing the entire fruit and pooping the seed out later, and that could have been done by any number of animals. The dodo probably did eat the fruits, but so did a lot of other animals that have also gone extinct on Mauritius.

In June of 2025, a study was published showing that the gomphothere Notiomastodon, which lived in South America until about 10,000 years ago, definitely ate fruit. Notiomastodon was an elephant relation that could probably grow almost ten feet tall, or 3 meters. It probably lived in family groups like modern elephants and probably looked a lot like a modern elephant, at least if you’re not an elephant expert or an elephant yourself. The 2025 study examined a lot of notiomastodon teeth, and it discovered evidence that the animals ate a lot of fruit. This means it would have been an important seed disperser, just like the African forest elephant that we talked about earlier.

Another plant that nearly went extinct after the mammoth did is a surprising one. Wild ancestors of modern North American squash plants relied on mammoths to disperse their seeds and create the type of habitat where the plants thrived. Mammoths probably behaved a lot like modern elephants, pulling down tree limbs to eat and sometimes pushing entire trees over. This disturbed land is what wild squash plants loved, and if you’ve ever prepared a pumpkin or squash you’ll know that it’s full of seeds. The wild ancestors of these modern cultivated plants didn’t have delicious fruits, though, at least not to human taste buds. The fruit contained toxins that made them bitter, which kept small animals from eating them. Small animals would chew up the seeds instead of swallowing them whole, which is not what the plants needed. But mammoths weren’t bothered by the toxins and in fact probably couldn’t even taste the bitterness. They thought these wild squash were delicious and they ate a lot of them.

After the mammoth went extinct, the wild squash lost its main seed disperser. As forests grew thicker after mammoths weren’t around to keep the trees open, the squash also lost a lot of its preferred habitat. The main reason why we have pumpkins and summer squash is because of our ancient ancestors. They bred for squash that weren’t bitter, and they planted them and cared for the plants. So even though the main cause of the mammoth’s extinction was probably overhunting by ancient humans, at least we got pumpkin pies out of the whole situation. However, I personally would prefer to have both pumpkin pie and mammoths.

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. 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 440: Trilobites!

Thanks to Micah for suggesting this week’s topic, the trilobite!

Further reading:

The Largest Trilobites

Stunning 3D images show anatomy of 500 million-year-old Cambrian trilobites entombed in volcanic ash

Strange Symmetries #06: Trilobite Tridents

Trilobite Ventral Structures

A typical trilobite:

Isotelus rex, the largest trilobite ever found [photo from the first link above]:

Walliserops showing off its trident [picture by TheFossilTrade – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=133758014]:

Another Walliserops individual with four prongs on its trident [photo by Daderot, CC0, via Wikimedia Commons]:

Show transcript:

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

This week we’re going to learn about an ancient animal that was incredibly successful for millions of years, until it wasn’t. It’s a topic suggested by Micah: the trilobite.

Trilobites first appear in the fossil record in the Cambrian, about 520 million years ago. They evolved separately from other arthropods so early and left no living descendants, that they’re not actually very closely related to any animals alive today. They were arthropods, though, so they’re distantly related to all other arthropods, including insects, spiders, and crustaceans.

The word trilobite means “three lobes,” which describes its basic appearance. It had a head shield, often with elaborate spikes depending on the species, and a little tail shield. In between, its body was segmented like a pillbug’s or an armadillo’s, so that it could flex without cracking its exoskeleton. Its body was also divided into three lobes running from head to tail. Its head and tail were usually rounded so that the entire animal was roughly shaped like an oval, with the head part of the oval larger than the tail part. It had legs underneath that it used to crawl around on the sea floor, burrow into sand and mud, and swim. Some species could even roll up into a ball to protect its legs and softer underside, just like a pillbug.

Because trilobites existed for at least 270 million years, there were a lot of species. Scientists have identified about 22,000 different species so far, and there were undoubtedly thousands more that we don’t know about yet. Most are about the size of a big stag beetle although some were tinier. The largest trilobite found so far lived in what is now North America, and it grew over two feet long, or more than 70 centimeters, and was 15 inches wide, or 40 cm. It’s named Isotelus rex.

I. rex had 26 pairs of legs, possibly more, and prominent eyes on the head shield. Scientists think it lived in warm, shallow ocean water like most other trilobites did, where it burrowed in the bottom and ate small animals like worms. There were probably other species of trilobite that were even bigger, we just haven’t found specimens yet that are more than fragments.

Because trilobites molted their exoskeletons the way modern crustaceans and other animals still do, we have a whole lot of fossilized exoskeletons. Fossilized legs, antennae, and other body parts are much rarer, and preserved soft body parts are the rarest of all. We know that some trilobite species had gills on the legs, some had hairlike structures on the legs, and many had compound eyes. A specimen with preserved eggs inside was also found recently.

Some incredibly detailed trilobite fossils have been found in Morocco, including details like the mouth and digestive tract. The detail comes from volcanic ash that fell into shallow coastal water around half a billion years ago. The water cooled the ash enough that when it fell onto the trilobites living in the water, it didn’t burn them. It did suffocate them, though, since so much ash fell that the ocean was more ash than water.

The ash was soft and as fine as powder, and it covered the trilobites and protected their bodies from potential damage, while also preserving the body details as they fossilized over millions of years. The fossils were discovered in 2015, about 509 million years after the trilobites died, and are still being studied.

Two species of trilobite have been found at this Morocco site, and the team is using non-invasive technology to study the preserved insides in one exceptionally preserved specimen. Its entire digestive system is intact, probably because the poor trilobite ended up swallowing a lot of ash before it died. The ash kept the soft tissues from decomposing.

Some trilobites had spines growing from their head shields and even from the rest of the exoskeleton. Scientists think these may have helped protect the animals from being eaten, but they might also have helped them navigate more easily in the water without getting flipped over by currents. One genus of trilobite, Walliserops, even had a structure sticking out from the front of its head called a trident.

The trident grew forward and slightly upward from the head, then split into three prongs. Scientists aren’t sure what it was for, but suggest that it acted as a nose spike like some modern beetles have, which allowed trilobites to fight each other for resources or mates. The tridents weren’t completely symmetrical, and one individual has even been found with a four-pronged trident. (I guess you would call that a quadrent.) Some species had long tridents, some short, but there’s no evidence that only males or only females had them.

Electron microscopes and other modern imaging technology have allowed scientists to learn more about what the trilobite looked like when it was alive. This includes some hints about different species’ coloration and markings. Most trilobites had good vision and were probably as colorful as modern crustaceans. Some rare trilobite fossils show microscopic traces of spots and stripes. One species studied may have had a brown stripe that faded to white along the edges of the body.

All trilobites went extinct at the end of the Permian, about 250 million years ago, during the extinction event called the Great Dying. We talked about it in detail in episode 227 so I won’t go over its causes and effects again except to say that an estimated 95% of all marine animals went extinct during that event. The Great Dying ended the trilobite’s successful 270 million year run on this amazing planet.

When I was little, I found trilobites fascinating. They were so common for so long, and then they were gone. I’ve always wondered if some trilobites survived the Great Dying and were still alive in the deep sea. I’m not the only one who’s wondered that, so let’s talk a little more about why the trilobites went extinct and how some of them might have survived.

Almost all trilobites we know of lived in shallow coastal water. We have trilobite tracks of an ancient low tide shore, which tells us that at least some species could leave the water and venture onto land occasionally, possibly the first animals on earth to do so. Coastal water is well oxygenated and we know trilobites had trouble surviving anoxic events, when the water where they lived had much less oxygen than usual. Anoxic events are actually what led to the Great Dying, but it wasn’t the first time the world’s oceans became less oxygenated. It happened in earlier extinction events too during the Devonian, around 372 and 359 million years ago, and each time many species and genera of trilobites went extinct. The trilobite was already in decline when the Great Dying occurred, with only a handful of genera left, and the extinction event finished them off once and for all according to the fossil record.

But we do know of a few species of trilobite that were adapted to the deep sea. Deep-sea animals have to evolve to be tolerant of low-oxygen conditions. The deep sea is also very little known by humans. It’s possible, even if it’s unlikely, that deep-sea trilobites survived the Great Dying and that their descendants are still around, unknown to science.

One interesting note, and an ongoing mystery about trilobites, is that while we know they were arthropods, we don’t actually know which branch of the phylum Arthropoda they’re most related to. That’s because there are no ancestral versions of the trilobite that have ever been found. When they appear in the fossil record, they’re already recognizably trilobites. It’s possible that the ancestral forms didn’t have exoskeletons that were likely to fossilize, or that we just haven’t found the right fossil bed yet. Until we learn more, it’ll remain a 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. 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 438: The Dragon Man Skull

This week we’re going to learn about a new finding about the skull referred to as the Dragon Man!

Further reading:

We’ve had a Denisovan skull since the 1930s—only nobody knew

The proteome of the late Middle Pleistocene Harbin individual

Show transcript:

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

It never fails that only a few days after our annual updates episode, a study is published that’s an important update to an older episode. This time it’s an update so important that it deserves its own episode, so let’s learn more about one of our own extinct close relations, the Denisovan people.

We didn’t know about the Denisovans until 2010, when DNA was sequenced from a finger bone found in Denisova Cave in Siberia in 2008. Scientists were surprised when the DNA didn’t match up with Neanderthal DNA, which is what they expected, since they knew Neanderthals had lived in the cave at various times over thousands of years. Instead, the DNA was for a completely different hominin, a close relation of both humans and Neanderthals.

Since then, researchers have found some Denisovan teeth, two partial mandibles, a rib fragment, and some other bone fragments, but nothing that could act as a type specimen. The type specimen is the preserved specimen of a new species, which is kept for scientists to study. It needs to be as complete as possible, so a handful of fragments just won’t work.

Even without a type specimen, having Denisovan DNA answered some questions about our own history as a species. Ever since scientists have been able to sequence genetic material from ancient bones, they’ve noticed something weird going on with our DNA. Some populations of people show small traces of DNA not found in other human populations, so scientists suspected they were from long-ago cross-breeding with other hominin species. When the Neanderthal genome was sequenced, it matched some of the unknown DNA traces, but not all of them.

Mystery DNA sequences in a closely related population are called ghost lineages. The Denisovan DNA matched the ghost lineage scientists had identified in some populations of people, especially ones in parts of east Asia, Australia, and New Guinea. This is your reminder that despite tiny genetic differences like these, all humans alive today are 100% human. We are all Homo sapiens.

Naturally, we as humans are interested in our family tree. We even have an entire field of study dedicated to studying ancient humans and hominins, paleoanthropology. Lots of scientists have studied the Denisovan remains we’ve found, along with the genetic material, but they really need a skull to learn so much more about our long-extinct distant relations.

Luckily, we’ve had a Denisovan skull since the 1930s. But wait, you may be saying, you just said we didn’t have anything but bone fragments and teeth! Why didn’t you mention the skull?

It’s because the skull was hidden by its finder, a Chinese construction worker. The man was helping build a bridge and was ashamed that he was working for a Japanese company. That region of China was under Japanese occupation at the time, and the man didn’t want anyone to know that he was working for people who were treating his fellow citizens badly. He thought the skull was an important find similar to the Peking Man discovery in 1929, so he hid the skull at the bottom of an abandoned well to keep it safe. He didn’t dare share any information about it until he was on his death-bed, when he whispered his secret to his son.

It wasn’t until 2018 that the man’s family took another look at the skull and realized it definitely wasn’t an ordinary human skull. It was obviously extremely old and had a pronounced brow and really big teeth.

In 2021 the skull was classified as a new species of hominin, Homo longi, where the second word comes from the Mandarin word for dragon. That’s because the area where it was found is called Dragon River.

But not everyone agreed that the Dragon Man skull, as it came to be known, was actually a new species. Scientists continued to study the skull, and finally, a paleoanthropologist named Qiaomei Fu and her team managed to extract DNA from the skull and one of its teeth. The resulting genetic profile indicated that the Dragon Man was a Denisovan.

The skull has been dated to 146,000 years ago, possibly older. It’s nearly complete, which provides a lot of information to scientists. Scientists are pretty sure Dragon Man was a fully grown male, but less than 50 years old when he died.

So what did Dragon Man look like when he was alive? We don’t know how tall he was or his overall build, although from the other Denisovan bones we have, we know Denisovans were a strong, robust people, similar to Neanderthals, and were more closely related to Neanderthals than humans. Dragon Man would have had a pronounced brow that would probably make his eyes look deep-set, and a large nose but a receding chin. Genetic markers indicate he probably had dark hair and eyes, and a medium shade of skin. If you had a time machine and could go back and meet Dragon Man when he was alive, you’d know at a glance that he wasn’t a Homo sapiens but he would probably look pretty normal in most respects.

One exciting note is that paleoanthropologists now think that three other ancient skulls from China may actually be Denisovan skulls. With luck they’ll be able to extract genetic material from them soon so we can learn more about our ancient cousins.

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. 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!