Episode 297: Dinosaur Mummies

This week we have a two-ghost rating for our episode about dinosaur mummies! It’s a little spooky because we talk about mummies, but it’s mostly an episode about dinosaurs, which are not spooky.

Further reading:

The lost Tarbosaurus mummy

Dinosaur Mummy Found with Fossilized Skin and Soft Tissues

Dakota the Dinomummy: Millenniums in the Making

Spectacularly Detailed Armored Dinosaur “Mummy” Makes Its Debut

Was a Dinosaur Mummy Dubbed ‘Appalachiosaurus’ Found in Tennessee?

An Edmontosaurus mummy found in 1908:

A 3D model of Dakota’s skin [photo from third link above]:

The Nodosaurid ankylosaur mummy:

Show transcript:

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

It’s monster month and this week we’ve got a monster from ancient times—really ancient times. We’re talking about mummies today, DINOSAUR mummies! On our spooky scale, this one rates two ghosts out of five since we do talk about mummies, but it’s not too spooky because we mostly talk about dinosaurs!

A dinosaur named Tarbosaurus lived around 70 million years ago in what is now Mongolia. It was probably closely related to Tyrannosaurus rex and would have looked very similar, with a big strong body but teeny-tiny front legs. Its front legs were even smaller than T. rex’s in relation to its body. It grew up to about 33 feet long, or 10 meters, and probably stood about 10 feet high at the hip, or 3 meters, and its big head had a big mouth full of really big teeth. It probably killed and ate hadrosaurs, sauropods, and other big dinosaurs. Some scientists think it was so closely related to T. rex that it should be classified as another species in the genus Tyrannosaurus.

We have quite a few Tarbosaurus fossils, including some very well-preserved skulls, so we know quite a bit about it. It had a good sense of smell and good hearing, but its vision wasn’t all that great. Some paleontologists think it might have been nocturnal. We’ve also found lots of bones of big dinosaurs with bite marks from teeth the size and shape of Tarbosaurus’s.

In 1991, though, a team of scientists found something even more incredible. They found a partial skeleton of a Tarbosaurus with lots of skin impressions. In short, they’d sort of found a mummified dinosaur. (It’s not really a mummy.)

The mummy consisted of the back end of the dinosaur, including the pelvis, tail, and hind legs. It had fallen onto sandy sediment that was especially fine-grained, so when the sediment transformed into sandstone over many millennia, it retained an exceptionally clear impression of the skin, including every small pebbly scale.

The expedition members took pictures and measurements, but they didn’t collect the specimen. Another expedition returned to the area to do so in 1993, but by then the specimen was gone. It was probably stolen by fossil poachers, who probably didn’t even realize the skin impressions were far more valuable than the bones and may have destroyed them while removing the skeleton.

The lost Tarbosaurus specimen is called a fossilized mummy since a dead animal’s skeleton with skin is sort of like a mummy. When the soft tissues of a dead animal or person are preserved in some way that causes them to stop decaying, that’s considered a mummy, and there are a lot of causes.

The most famous mummies, of course, are from ancient Egypt. It was important in Egyptian culture at the time to preserve a dead person’s body, and dead animals were also mummified sometimes, especially cats. The body was treated with salt and spices that helped dry the tissues and preserve them from bacteria, and once it was fully dehydrated the body was wrapped in linen bandages, covered with a natural waterproofing material made from plant resins, and placed in a wooden coffin. Sometimes the coffin was then put into a stone sarcophagus to keep it extra safe.

Other cultures across the world have practiced mummification too, and sometimes mummification happens naturally. This mostly happens in deserts and other dry areas, or in places where it’s very cold and the body freezes before it can decay, then dries out slowly. Sometimes a body is preserved after it’s buried, when the soil of the grave or the conditions in an underground crypt are just right, although bodies found in bogs are mummified too since bogs lack oxygen and that stops the decay of soft tissues.

Another dinosaur mummy was found in 1910 in the western United States, in Wyoming. It’s an Edmontosaurus specimen that’s remarkably well preserved and nearly complete, including skin impressions and even the horny beak. Initially the scientists who studied the animal thought the stomach contents had been preserved too, but more modern studies have concluded that the plant material was probably deposited in the body cavity after death. The dinosaur died near water and flooding may have washed plants into the partially decomposed carcass. There was even a little fish among the plant material, which was probably already dead when it was washed into the body cavity.

Edmontosaurus lived in what is now North America around 67 million years ago, surviving right up to the extinction event that killed off the non-avian dinosaurs. It’s one of many species of hadrosaurid, which are often called duck-billed dinosaurs. It could grow up to 39 feet long, or 12 meters, and possibly larger, and it was relatively common throughout its range. It probably walked on all fours most of the time but could stand or walk on its hind legs only, when it wanted to. It ate plants and may have migrated long distances to find food. It probably lived in groups.

The skin impressions of the 1910 specimen were impressive, but it isn’t the only edmontosaurus mummy ever found. We have several, in fact. The earliest was found in 1908, known as specimen AMNH 5060, and it was discovered by a man named Charles Sternberg and his three sons, who all three became paleontologists later in life. They were hoping to find a good triceratops skull to sell to a museum, but they found something even better when one of the sons realized the dinosaur they were uncovering was wrapped in skin impressions.

AMNH 5060 had died in an area that was very dry, so instead of rotting away, all the moisture in the body dried out and the skin remained stretched across the bones. It was essentially a natural mummy at that point. Then, as in the 1910 specimen, flooding probably covered the dead animal with sediment that preserved it in fine detail. Not only is the skeleton mostly intact, it’s also articulated so that the fossilized body parts are in the same places they were when the animal died, instead of having been scattered around after death.

More edmontosaurus mummies were found later, too, but it wasn’t until 2006 when the most important find so far was discovered in North Dakota, part of the United States. It isn’t just skin impressions we have from this specimen, which is nicknamed Dakota. We have actual fossilized skin and muscles and tendons, along with bones.

Dakota was discovered by Tyler Lyson on his uncle’s ranch when he was still in high school. He knew the dinosaur was there but he didn’t realize how important the find was until five years later when he was a paleontology student. The specimen was excavated in 2006 and was identified as an adolescent edmontosaurus that died about 67 million years ago. It was recently given a new 3D scan and results will hopefully be published soon, letting us all know if there are any fossilized organs inside the body.

Because so much of the soft tissues were preserved in place, we know a lot about how edmontosaurus looked when it was alive. For instance, the intervertebral discs that act as little shock absorbers between vertebrae are still in place, which means we know exactly how long Dakota was when it was alive, about 40 feet long, or 12 meters. Because so many of its tendons and muscles are preserved, scientists can calculate how fast it could run. Dakota could probably run 28 mph, or 45 km/hour. We even have a clue about Dakota’s pattern, if not its coloration. Differences in scale size and texture suggest that the dinosaur might have had stripes on at least part of its body.

Edmontosaurus fossils aren’t the only dinosaur mummies, though. In 2011, an amazing ankylosaur fossil was discovered in a Canadian mine. Ankylosaurs had short legs and wide bodies covered in armor, and while some had club-like tails, Nodosaurids had regular tails but spikes on their backs that pointed sideways. The Canadian ankylosaur mummy is a nodosaurid.

Researchers think the dinosaur was probably caught in a flash flood, which swept it out to sea. It probably swam as long as it could, but its armored body made it heavy and it eventually drowned. Its body sank into the bottom sediment, which protected it from decay, scavengers, weathering, and other things that might have destroyed it. 110 million years later, an equipment operator fortunately noticed how weird the rock was that he’d just uncovered, and the world now has an amazing idea of what a living ankylosaur looked like.

The animal’s armored plates from the front of its body, some skin, and even its stomach contents are beautifully preserved, and the body is still articulated. It looks like it lay down to sleep and turned to stone. Some chemical pigments called melanosomes were discovered during study of the skin, which suggests that its skin was probably reddish-brown in color with a lighter-colored belly. It had massive spikes on its shoulders and along the sides of its neck, along with the smaller osteoderms that made up its armor on the rest of its body.

We know it mostly ate ferns because that was mostly what was in its stomach when it died. There was also some charcoal in its stomach, and researchers think it was probably eating ferns that had grown in an area where a wildfire had been recently. The ferns are so well preserved that scientists can determine their stage of growth, which means the dinosaur probably died in early to mid-summer.

Another dinosaur mummy is a Brachylophosaurus nicknamed Leonardo. Leonardo was found in July 2000 and wasn’t full grown when it died, only maybe three or four years old. Its skin and some of its internal organs are fossilized, and 3D scans have allowed scientists to learn a lot about it.

Brachylophosaurus was a hadrosaurid that lived around 80 million years ago in North America, and it could grow up to around 36 feet long, or 11 meters. It may have lived and migrated in groups. It had a flat crest on its head and a frill down the back, although some individuals had big crests and some had small ones. Paleontologists think big crests might have been a trait found only in males or only in females, we’re not sure which.

It ate plants, and we know from studies of Leonardo’s fossilized digestive system that it had eaten a lot of ferns right before it died, as well as leaves and other material from ancient relatives of conifers and magnolias. It also had worms. That’s right, even the parasites in Leonardo’s digestive system were fossilized. They were needle-like bristly worms who left more than 200 tiny burrows in the digestive lining, fossilized for eternity. Leonardo also had an internal pouch in its neck that was similar to a modern bird’s crop, where food was stored immediately after swallowing and where the digestive process may have started.

We’ll finish by talking about a story from April 2022, which discusses a dinosaur mummy found in my own state of Tennessee. The dinosaur was called Appalachiosaurus and was at least 77 million years old, and its skin and even some of its internal organs were reportedly intact—so much so that DNA was able to be extracted from them. The problem is that this particular story was posted to Facebook on April 1, also known as April Fool’s Day, and yes, it was a hoax. But Appalachiosaurus is a real species of dinosaur, a theropod that grew at least 21 feet long, or 6.5 meters, and probably quite a bit longer since the most complete specimen found so far is a juvenile. We don’t know a lot about Appalachiosaurus since only a few partial remains have ever been discovered. It would be fantastic if a fossilized mummy of one really did turn up one day.

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 294: Updates 5 and a New Zealand Parrot!

It’s our fifth updates and corrections episode, with some fun information about a New Zealand parrot, suggested by Pranav! Thanks also to Llewelly, Zachary, Nicholas, and Simon who sent in corrections.

Further reading:

Vitiligo

Tyrannosaurus remains hint at three possible distinct species

Study refutes claim that T. rex was three separate species

The reign of the dinosaurs ended in spring

Impact crater may be dinosaur killer’s baby cousin

California mice eat monarch butterflies

‘Hobbit’ human story gets a twist, thanks to thousands of rat bones

Playground aims to distract mischievous kea

The kea showing off the bright colors under its wings:

A kea jungle gym set up to stop the birds from moving traffic cones around for fun:

Show transcript:

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

This is our fifth annual updates episode, where I catch us up on new studies published about various animals we’ve talked about before. This is mostly just whatever happens to catch my eye and isn’t comprehensive by any means. Also, because things have been so busy for me the last few weeks, I decided to just go with what I’d already finished and not try to add more.

We’ll start as usual with corrections, then do some updates, then learn about a parrot from New Zealand, which was a suggestion from Pranav. This part of the episode started as a Patreon episode from 2019, so patrons, I promise your October bonus episode will be brand new and interesting and in-depth!

First, both Llewelly and Zachary pointed out that there are lions living in Asia, not just Africa. It’s called the Asiatic lion and these days, it only lives in a few small areas in India. It’s a protected animal but even though their numbers are increasing, there are probably still no more than 700 Asiatic lions living in the wild.

Next, Nicholas points out that vitiligo isn’t a genetic condition, it’s an autoimmune disorder that can be caused by a number of different diseases and conditions. You still can’t catch it from other people, though. We talked about vitiligo briefly in episode 241, about squirrels. Nicholas included a link, which I’ll put in the show notes for anyone who’s interested in learning more.

For our final correction, Simon questioned whether there really are only six living species of macaw known. This was polite of him, since I was completely wrong about this. In fact, there are six genera of macaws and lots of species, although how many species there are exactly depends on who you ask. Since this mistake made it into the Beyond Bigfoot & Nessie book, I am very irritated at myself, but thank you to Simon for helping me clear this up.

Let’s start our updates with the animal who gets an update every single time, Tyrannosaurus rex. A study published in February 2022 examined the fossilized remains of 37 T. rexes and suggested that there may actually be three distinct species of T. rex instead of just one. The study focused specifically on differences in teeth and leg bones that don’t seem to have anything to do with the individual’s age when it died or whether it was male or female.

However, in July 2022, another study found that all the T. rexes found so far do indeed belong to the same species. This is how science works, because new information is always being discovered and that means we have to reassess the things we thought we knew.

In other dinosaur news, in episode 240 we talked about the last day of the dinosaurs. Results of a study released in February 2022 suggest that the asteroid struck in early spring in the northern hemisphere. The asteroid hit the earth so hard that it rocked the entire continental plate that it struck, which caused massive waves unlike any other waves, since all the water above the continental plate was pushed upwards at once. This pushed all the sediment lying quietly on the bottom of the ocean up into the water, so much of it at once that it actually buried a lot of fish alive. The same thing happened in lakes and every other body of water. The fossil site we talked about in episode 240 is still being studied, the one that appears to date to literally the day of the asteroid impact, and preserved soft tissues in some of the fish have been discovered. Careful analysis of the fish show evidence that they all died in early spring. Researchers suggest that the time of year may have been especially bad for many dinosaurs, who were probably just starting to lay eggs and have babies.

In even more recent last-day-of-the-dinosaurs news, in August 2022 a study was released about a newly discovered crater off the coast of West Africa. Researchers are pretty sure it was from an asteroid impact, although much smaller than the big one that hit what is now Mexico and led to the extinction of all non-avian dinosaurs. They’re also not completely certain when it formed, since it’s deep under the sea floor these days and was only discovered when scientists were examining seismic survey data of the sea floor. But it does seem to have formed about 66 million years ago, and another crater found in Ukraine is also about the same age. In other words, there may have been more than one asteroid that hit earth at the same time, either because a bigger asteroid broke into pieces as it entered earth’s atmosphere, or because smaller asteroids were orbiting the bigger one.

We’ve talked about the monarch butterfly several times, especially in episode 203. The monarch is a beautiful orange and black butterfly that migrates from the United States and Canada into central Mexico for the winter, where it gathers in huge groups. The monarch butterfly caterpillar primarily eats the milkweed plant, which contains toxins that the caterpillar stores in its body. Those toxins remain in the body even after the caterpillar has transformed into a butterfly, meaning the butterflies are toxic too. Birds and other animals learn to recognize the bright orange and black pattern of the butterfly and avoid eating it, because it tastes bad and makes them sick.

But a study from December 2021 determined that one animal does eat monarch butterflies, and a whole lot of them. Many species of mouse that live where monarch butterflies spend the winter, in a few spots in Mexico and California, will eat the butterflies, especially ones that fall to the ground either by accident or because they’re unhealthy and weak. The mice show resistance to the butterfly’s toxins.

Research into the small hominin remains on the island of Flores is ongoing, and the most recent findings shed some light on what might have happened about 60,000 years ago. The so-called Hobbit fossils have all been found at Liang Bua, a giant cave, but lots of other fossils have been found at the same site. A whole lot of those are from various species of rodent, especially rats, ranging in size from mouse-sized to ordinary rat-sized to giant rat sized, over two feet long including the tail, or about 75 cm.

Because we know a lot about the rats that lived on Flores, and in some cases still live there, we can infer a lot about what the area around Liang Bua was like over the centuries. Until about 60,000 years ago, most of the rat remains found were of medium-sized species that like open habitats. That means the area around Liang Bua was probably pretty open. But after about 60,000 years ago, there’s a big shift in what kind of rodents appear in the fossil record. More rats of smaller size moved in, ones that were adapted for life in forests, while the medium-sized rats moved out. That corresponds with other animals disappearing from the fossil record in and around the cave, including a species of Komodo dragon and a subspecies of Stegodon, an elephant relation that exhibited island dwarfism and was about the size of a cow. The Flores little people remains also vanish from the cave during this time, until by 50,000 years ago there are no signs of them.

But that doesn’t mean that H. floresiensis went extinct at that time. Researchers now think that as the land around the cave became more heavily forested, the Flores little people moved to other parts of the island that were more open. We don’t know where yet, and as a result we don’t know when exactly they went extinct. They might even have left the island completely. One neighboring island is Sulawesi, and researchers have found small stone tools on that island that are very similar to those made by H. floresiensis.

Modern humans probably arrived on the island of Flores about 46,000 years ago, and it’s possible that when they did, their small-statured cousins were still around.

We’ll finish with Pranav’s suggestion, a New Zealand parrot called the kea!

The kea is a type of parrot, but it doesn’t look much like a parrot at first glance. Parrots usually have brightly colored feathers but the kea appears more drab initially. It’s olive green with black-laced feathers, but it has bright orange feathers under its wings that show when it flies and the tips of its wings are blue. It’s a big, heavy bird with a wingspan more than three feet across, or one meter, and it has a big hooked beak like other parrots. It lives in the mountains of New Zealand’s South Island, the only parrot that lives in such a cold environment.

The kea is an omnivore but it mostly eats plants and insects. It will eat roadkill, small animals like rabbits, chicks of other species of bird, and trash. For over a century there were rumors that the kea would attack sheep, which led to the New Zealand government paying a bounty for dead keas that wasn’t lifted until 1970. By the time the bounty ended, there were only around 5,000 keas left, and even then the bird wasn’t fully protected until 1986.

So does the kea kill sheep or was that just an excuse to kill birds? Actually, the kea does attack sheep, or at least some keas do. Most of the attacks aren’t fatal, but we definitely know it happens because someone got it on video in 1992.

The keas land on the sheep’s back and pull out hunks of wool, which exposes and injures the skin underneath. Then they use their sharp beaks to dig into the wound and eat the fat from the living sheep. This can result in the sheep dying from infection and shock, naturally, so it’s no wonder sheep farmers disliked the kea. But the sheep is not an animal native to New Zealand while the kea is, plus the kea primarily eats plants—and sheep destroy the plants the kea eats, especially the ones high in vegetable lipids that provide the same high energy food that sheep fat does.

Besides, there’s some tantalizing evidence that the kea used to do the same thing to the moa, a huge flightless bird that lived in New Zealand until it went extinct after humans arrived. Moa bones dating to 4,000 years ago and found in a swamp along with lots of other well-preserved bones show markings on the pelvis that may be from kea beaks.

Like other parrots, the kea is remarkably intelligent and known for its tool use. It’s also infamous for its curiosity and willingness to disassemble things, including cars. I found an article about the kea in New Zealand Geographic that has some awesome stories about the bird, like this one that I’ll quote.

“In September 1983, the Old Pompolona Hut on the Milford Track was destroyed by flood when the pent-up Clinton River broke through its winter avalanche dam. The walking track season was only six weeks away. Planners, builders and helicopter crews worked night and day to complete a new hut complex before the first walkers arrived.

“The local clan of kea took a keen interest in all this frantic activity after a cold and quiet winter. Just what were these people up to? One bird, for whom building materials seemed to hold a particular attraction, began stealing nails. So persistent was the bird’s thievery that an exasperated carpenter chased it (in vain) over the roof of the new main hut. While his back was turned, another kea stole his packet of roll-your-owns, shredding tobacco and papers to the raucous approval of spectator kea perched in nearby trees.

“Weeks later, after the new hut had been completed, the purloined nails were discovered. They had been neatly laid in the gutters of an outbuilding’s iron roof, sorted according to size.”

The kea’s intelligence, tool use, and problem-solving abilities line up with those in corvids like crows and ravens. Studies show that corvids are more successful figuring out tasks that require them to make pecking motions in one way or another while parrots, including the kea, are more successful when the tasks require pulling motions. This makes sense, since parrots have a hooked beak that they use to pull things apart, like rotting logs to get at grubs, while corvids have straight beaks that they use to stab through things to find food.

The kea is also really sociable. Young keas play together, often using items as toys. For instance, from the same article, witnesses at a ski resort watched a kea steal a plastic mug, fly off with it, and start up a game of catch with it with a group of other keas.

The kea even has a particular call it makes to encourage other keas to play. In a recent study, when the call was broadcast to some captive keas over a loudspeaker, the keas immediately started a game of chase. Researchers think the call isn’t so much an invitation to play but is more like laughter which makes other keas want to laugh along, or in this case play.

This is what the play call sounds like:

[kea call]

The kea builds its nests in burrows it digs in the ground, with some burrows 20 feet long, or 6 meters. The nesting chamber is lined with soft plant material. Females lay two to five eggs, which hatch in about three weeks. Despite the parents’ care, more than half of babies don’t survive their first year, mostly due to introduced predators like rats, stoats, and possums. But if a kea survives to grow up, it can live up to 50 years or possibly more.

Young keas, like young adult humans, can cause a lot of mischief that sometimes leads to tragedy. A lot of keas are killed by cars because they find cars and roads interesting. They especially like to move road cones, which of course is also dangerous to humans. One community set up a kea jungle gym well off the road to give keas a safe place to play, and it succeeded so well that other communities have built kea jungle gyms too.

Kea numbers are improving slowly, with an estimated 7,000 individuals alive today. Part of the problem is that keas find humans interesting. They like our things, which they want to steal or destroy, and they like our junk food, which they want to eat. In other words, they’re suspiciously like us. Only they can fly.

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 293: Bat-Winged Dinosaurs and an Actual Bat

We’ll have a real episode next week but for now, here are two Patreon episodes smashed together into one!

Happy birthday to Speed!

Further reading:

Yi qi Is Neat But Might Not Have Been the Black Screaming Dino-Dragon of Death

Yi qi could probably glide instead of actually flying:

The Dayak fruit bat [photo by Chien C. Lee]:

Show transcript:

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

I’ve finally finished moving, although I’m still in the process of unpacking and finding places for all my stuff. I haven’t had the chance to do any research this week, so this episode is actually two repurposed Patreon episodes, one from June of 2019 and one from May of 2021. They’re both short episodes so I put them together. I apologize to patrons for not getting something new this week, but I think everyone else will find these animals interesting.

But first, we have a birthday shout-out! A great big happy birthday to Speed! I hope this next year is the very best one yet for you!

Please excuse the varying quality of audio.

Listener Simon sent me an article about a recently discovered dinosaur with batlike wings, only the second batwinged dinosaur ever discovered. I thought that would make a really neat episode, so thank you, Simon!

These are really recent discoveries, both from the same area of northeastern China. In 2007 a small fossil found by a farmer was bought by a museum. A paleontologist named Xing Xu thought it looked interesting. Once the fossil had been cleaned and prepared for study, Xing saw just how interesting it was.

The dinosaur was eventually named Yi qi, which means strange wing. It was found in rocks dated to about 163 million years ago. Yi qi was about the size of a pigeon and was covered with feathers. The feathers were probably fluffy rather than the sleek feathers of modern birds. But most unusual was a long bony rod that grew from each wrist, called a styliform element. Yi qi also had very long third fingers on each hand. The long finger was connected to the wrist rod by a patagium, or skin membrane, and another patagium connected the wrist rod to the body. So even though it had feathers on its body, it probably didn’t have feathered wings. Instead, its forelimbs would have somewhat resembled a bat’s wings.

Paleontologists have studied the fossilized feathers with an electron microscope and discovered the structures of pigments that would have given the feathers color. Yi qi was probably mostly black with yellow or brown feathers on the head and arms. It probably also had long tail feathers to help stabilize it in the air.

Ambopteryx longibrachium was only discovered in 2017, also in northeastern China. It also lived around 163 million years ago and looked a lot like Yi qi. The fossil is so detailed it shows an impression of fuzzy feathers and even the contents of the animal’s digestive tract. Its body contained tiny gizzard stones to help it digest plants but also some bone fragments from its last meal, so paleontologists think it was an omnivore. Its hands have styliform elements, although not a wrist rod like Yi qi, and there’s a brownish film preserved across one of its arms that researchers think are remains of a wing membrane.

Paleontologists think the bat-winged dinosaurs were technically gliders. Careful examination of the wrist rods show no evidence that muscles were attached, so the dinosaurs wouldn’t have been able to adjust the wings well enough to actually fly. Modern bats have lots of tiny muscles in their wing membranes to help them fly.

Yi qi’s wrist rod isn’t unique in the animal world. The flying squirrel has styliform rods made of cartilage that project from the wrists, with the patagia attached to them. When a squirrel wants to glide, it extends its arms and legs and also extends the wrist rods, stretching the patagia taut. It can even control its glide to some extent by adjusting the wrist rods.

These two bat-winged dinosaurs were related, but they aren’t direct ancestors to modern-day birds. They’re scansoriopterygids,[scan-soarie-OPterigid] which are related to the group of dinosaurs that gave rise to birds. We only have five scansoriopterygid fossils, all found in the same area of China, but they’re all exceptionally well preserved fossils. Scansoriopterygids all appear to have been good climbers. They probably mostly lived in trees and mostly ate insects and small animals, gliding from branch to branch like modern flying squirrels do.

Researchers suggest the bat-winged dinosaurs might have gone extinct when bird ancestors evolved true flight with feathered wings, outcompeting the bat-winged dinosaurs’ more limited gliding flight. But with so few fossils, it’s impossible to say how successful the bat-winged dinosaurs were. All we know is they are rare in the fossil record and left no descendants.

So were scansoriopterygids related to pterosaurs? Nope. Pterosaurs weren’t even dinosaurs. They were reptiles and the first vertebrates we’ve found that could actually fly instead of just glide. Pterosaurs first appear in the fossil record around 228 million years ago and they all went extinct about 66 million years ago in the Cretaceous-Paleogene extinction event.

When Yi qi’s description was first published in 2015, the media acted as though it was a radical new find that would change the way we looked at dinosaurs forever. Some people even claimed the fossil was a fake, either a deliberate fraud by Xing and the other paleontologists that worked on the specimen, or that Xing and the others actually had a fossil made up of more than one animal with the bones jumbled together, which they had mistaken for a single animal. But this isn’t the case. Yi qi has been studied extensively with all the technology paleontologists have available these days. It’s the fossil of a single animal and it hadn’t been touched up or altered or messed with in any way before it was prepared by an expert. But while it is a radical new finding, it’s not as radical as some articles made it seem.

In 2008, the description was published of another scansoriopterygid called Epidexipteryx. Epidexipteryx appears to be closely related to Yi qi. It doesn’t have a wrist rod, but its arms were long and its fingers were especially elongated. It had forward-pointing teeth in the front of its jaw and probably had long tail feathers. Paleontologists think it was most likely a strong climber that may have spent most of its time in and around trees. But after that publication, paleontologist Andrea Cau published a paper suggesting that Epidexipteryx’s elongated arms and fingers might have been connected with patagia that allowed it to glide short distances. This was before the first paper about Yi qi was published and before Ambopteryx was even discovered. So the idea of a dinosaur with gliding membranes was already out there.

Hopefully, more scansoriopterygid fossils will be found and studied soon, which will give us more knowledge about what these little animals really looked and acted like. I want one as a pet.

Next, let’s go from bat-winged dinosaurs to some actual bats, specifically an unusual feature found in at least one species of bat, and something of a mystery.

As you probably know, only female mammals lactate. That just means that after a mammal gives birth, the mother produces milk for her baby to drink until it’s old enough to eat the same food that its parents do. All mammals do this, from whales to vampire bats, from humans to kangaroos, from mice to lions. The word mammal actually comes from mammary gland, which is the gland that allows a mother animal to produce milk after she has a baby.

Researchers have examined the genes that allow for milk production and determined that the genes probably developed over 200 million years ago in the common ancestor of all mammals alive today. The genes responsible for making egg yolk proteins started to be lost around 70 million years ago, except in monotremes that still lay eggs. Monotremes are platypuses and echidnas, and while they’re mammals, they retain some features that modern mammals have lost, like egg-laying. But even monotreme mothers produce milk.

Once our far-distant mammal ancestors evolved the ability to feed its babies with milk, the babies didn’t need as much yolk in their eggs. Gradually, over millions of generations, mammals lost the ability to produce egg yolks completely. I mean, except for the monotremes. From now on just assume that any time I talk about modern mammals, in this episode at least, I’m excluding monotremes, because they’re weird.

Ancient mammals laid eggs like reptiles and birds do, with a shell protecting the yolk and other fluids inside, that in turn protected and nourished the growing baby. But eventually a mammal mother retained her eggs in the body, which meant they didn’t need an eggshell since they were safely inside her, and because she was able to feed them nutritious, easy to digest milk as soon as they were born, they didn’t need an egg yolk either. So mammals eventually lost the ability to produce eggs at all.

This gets confusing, of course, because we use the same word, “egg,” to refer to the egg that a chicken or turtle lays, and to refer to the cell that a mother animal produces that can develop into a baby if it’s fertilized by sperm. Obviously I’m just talking about the first kind of egg here.

Anyway, milk production is a complex process that can be hard on the mother’s body, since she has to produce enough nutrients to feed all her babies, whether that’s just one human infant or twin fawns or a whole litter of puppies or kittens. Researchers have compared the genes associated with milk production and discovered that it’s pretty standard across all mammals. While the nutrients available in milk vary from species to species, since not every mammal has the same nutritional needs, how the body produces milk is pretty much identical across the board. All female mammals produce milk after they give birth, but only the females.

If that’s the case, though, why do male mammals have nipples? It turns out that nipples are just part of the basic body plan of a mammal. Some researchers think that originally both males and females lactated, but over the generations males lost the ability.

Except in one case. In that species, the females produce milk…and so do the males.

The Dayak fruit bat lives in parts of southeast Asia and is quite rare. It lives in rainforests and mostly eats fruit, especially figs. It has short, gray-brown fur and only weighs a little more than three ounces, or 95 grams. That’s about the same weight as a deck of cards. Its wingspan is about 18 inches across, or 46 cm. It’s a nocturnal bat but it’s also a megabat, which if you remember episode 88 means that it doesn’t have the advanced echolocation ability that microbats have. It may only navigate through the trees using its vision, since it has large eyes, but it may have some form of echolocation ability we don’t know about yet. There’s a whole lot we don’t know about the Dayak fruit bat.

What we do know is that in summer, female Dayak fruit bats give birth to one or two babies. We also know that in summer, when researchers net bats to examine, both males and females have enlarged breasts that produce milk. The bat, by the way, has breasts toward the sides of its body, basically in the armpits of its wings because that’s most convenient for the baby bats to grab hold of.

That’s all we know so far. We don’t know for sure that the males actually nurse their babies. They don’t produce nearly as much milk as females do, only about 1/10th as much. Some researchers think the father bat may take care of his babies while the mother finds food, but that she takes care of them the rest of the time. That’s just speculation, though, because so little is known about the bat.

Sometimes various diseases, genetic issues, or pollutants in the environment will cause a male animal to produce a little milk, but that’s rare. All the male Dayak fruit bats caught in summer were lactating, as were the females. Males and females caught at other times of the year weren’t lactating. Since mammals stop producing milk after their babies no longer need it, that means both males and females are probably producing milk for babies.

There may be one other bat where males lactate, although I can’t find enough information to verify it. The Bismarck masked flying fox, which sounds like an old-timey superhero, is related to the Dayak fruit bat, since they’re both megabats, but they’re not closely related.

The Bismarck masked flying fox lives in Papua New Guinea and eats fruit and other plant material. Like other flying foxes, it probably finds its food by smell and can’t echolocate. We don’t know much about it either, though, and until 2001 researchers thought it was a subspecies of Temminck’s flying fox. If you do a search for it online, every entry you find will mention that the males lactate, but never with any documentation to back up the claim. So that’s a mystery for now, although I’ll keep trying to find out 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 291: The Ediacaran Biota

This week let’s find out what lived before the Cambrian explosion!

A very happy birthday to Isaac!

Further reading:

Some of Earth’s first animals–including a mysterious, alien-looking creature–are spilling out of Canadian rocks

Say Hello to Dickinsonia, the Animal Kingdom’s Newest (and Oldest) Member

Charnia looks like a leaf or feather:

Kimberella looks like a lost earring:

Dickinsonia looks like one of those astronaut footprints on the moon:

Spriggina looks like a centipede no a trilobite no a polychaete worm no a

Glide reflection is hard to describe unless you look at pictures:

Trilobozoans look like the Manx flag or a cloverleaf roll:

Cochleatina looked like a snail:

Show transcript:

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

It’s the last week of August 2022, so let’s close out invertebrate August with a whole slew of mystery fossils, all invertebrates.

But first, we have a birthday shoutout! A humongous happy birthday to Isaac! Whatever your favorite thing is, I hope it happens on your birthday, unless your favorite thing is a kaiju attack.

We’ve talked about the Cambrian explosion before, especially in episode 69 about some of the Burgess shale animals. “Cambrian explosion” is the term for a time starting around 540 million years ago, when diverse and often bizarre-looking animals suddenly appear in the fossil record. But we haven’t talked much about what lived before the Cambrian explosion, so let’s talk specifically about the Ediacaran (eedee-ACK-eron) biota!

I was halfway through researching this episode when I remembered I’d done a Patreon episode about it in 2021. Patrons may recognize that I used part of the Patreon episode in this one. You’d think that would save me time but surprise, it did not.

The word Ediacara comes from a range of hills in South Australia, where in 1946 a geologist noticed what he thought were fossilized impressions of jellyfish in the rocks. At the time the rocks were dated to the early Cambrian period, and this was long before the Cambrian explosion was recognized as a thing at all, much less such an important thing. But since then, geologists and paleontologists have reevaluated the hills and determined that they’re much older than the Cambrian, dating to between 635 to 539 million years ago. That’s as much as 100 million years before the Cambrian. The Ediacaran period was formally designated in 2004 to mark this entire period of time, although fossils of Ediacaran animals generally start appearing about 580 million years ago.

Here’s something interesting, by the way. During the Ediacaran period, every day was only 22 hours long instead of 24, and there were about 400 days in a year instead of 365. The moon was closer to the earth too. And life on earth was still sorting out the details.

Fossils from the Ediacaran period have been discovered in other places besides Australia, including Namibia in southern Africa, Newfoundland in eastern Canada, England, northwestern Russia, and southern China. Once the first well-preserved fossils started being found, in Newfoundland in 1967, paleontologists started to really take notice, because they turned out to be extremely weird. The fossils, not the paleontologists.

Many organisms that lived during this time lived on, in, or under microbial mats on the sea floor or at the bottoms of rivers. Microbial mats are colonies of microorganisms like bacteria that grow on surfaces that are either submerged or just tend to stay damp. Microbial mats are still around today, usually growing in extreme environments like hot springs and hypersaline lakes. But 580 million years ago, they were everywhere.

One problem with the Ediacaran biota, and I should explain that biota just means all the animals and plants that live in a particular place, is that it’s not always clear if a fossil is actually an animal. Many Ediacaran fossils look sort of plant-like. At this stage, the blurry line between animals and plants was even more blurry than it is now, with the added confusion that sometimes non-organic materials can resemble fossils, and vice versa.

For instance, the fossil Charnia, named after Charnwood Forest in England where it was first discovered. In 1957, a boy named Roger, who was rock-climbing in the forest, found a fossil that looked like a leaf or feather. He took a rubbing of the fossil and showed his father, who showed it to a geologist. The year before, in 1956, a 15-year-old girl named Tina saw the same fossil and told her teacher, who said those rocks dated to before the Cambrian and no animals lived before the Cambrian, so obviously what she’d found wasn’t a fossil.

Tina’s teacher was wrong about that, of course, although he was correct that the rocks dated to before the Cambrian, specifically to about 560 million years ago. But while Charnia looks like a leaf, it’s not a plant. This was about 200 million years before plants evolved leaves, and anyway Charnia lived in water too deep for plants to survive. It anchored itself to the sea floor on one end while the rest of the body stuck up into the water, and some specimens have been found that were over two feet long, or 66 cm. Some researchers think it was a filter feeder, but we have very little evidence one way or another.

One common animal found in Australia and Russia is called Kimberella, which lived around 555 million years ago and might have been related to modern mollusks or to gastropods like slugs. It might have looked kind of like a slug, at least superficially. It grew up to 6 inches long, or 15 cm, 3 inches wide, or 7 cm, and an inch and a half high, or 4 cm, which was actually quite large for most animals that lived back then. It was shaped roughly like an oval, with one thin end that stuck out, potentially showing where its front end was, although it didn’t have a head the way we think of it today. The upper surface of its body was protected by a shell, but not the type of shell you’d find on the seashore today. This was a flexible, non-mineralized shell, basically just thick, toughened tissue with what may be mineralized nodules called sclerites embedded in it. All around its body was a frill that might have acted as a gill. The underside of Kimberella was a flat foot like that of a slug.

We know Kimberella lived on microbial mats on the sea floor, and it might have had a feeding structure similar to a radula. That’s because it’s often found associated with little scratches on its microbial mat that resemble the scratches made by a radula when a slug or related animal is feeding on a surface. The radula is a tongue-like organ studded with hard, sharp structures that the animal uses to scrape tiny food particles from a surface.

Kimberella displays bilateralism, meaning it’s the same side to side. That’s the case with a lot of modern animals, including all vertebrates and a lot of invertebrates too, like insects and arachnids. But other Ediacarans showed radically different body plans. Charnia, for instance, exhibits glide reflection, where both sides are the same as in bilateralism, but the sides aren’t exactly opposite each other. If you walk along a beach and make footprints in the sand, your trail of footprints actually demonstrates glide reflection. If you stand on the sand and jump forward with both feet together, your footprints demonstrate bilateralism since the prints are side by side. (This is confusing to describe, sorry.) Pretty much the only living animals with this body pattern are some sea pens, which get their name because they resemble old-fashioned quill pens. Many sea pens look like plants, and for a long time researchers thought Charnia might be an ancient relation to the sea pen. These days most researchers are less certain about the relationship.

A similar-looking animal that lived around the same time as Charnia was Dickinsonia. It looks sort of like a leaf too, but a more broad oval-shaped leaf instead of a long thin one like Charnia. It’s also not a leaf. Some are only a few millimeters long, but some are over 4 1/2 feet long, or 1.4 meters.

Dickinsonia may be related to modern placozoans, a simple squishy creature only about one millimeter across. It travels very slowly across the sea floor and absorbs nutrients from whatever organic materials it encounters. But we don’t know if Dickinsonia was like that or if it was something radically different. Until a few years ago a lot of paleontologists thought Dickinsonia might be some kind of early plant or algae. Then, in 2016, a graduate student discovered some Dickinsonia fossils that were so well preserved that researchers were able to identify molecular information from them. They found cholesteroids in the preserved cells, and since only animals produce cholesteroids, Dickinsonia was definitely an animal. But that’s still about all we know about it so far.

Spriggina is another animal that at first glance looks like a leaf or feather. Then it sort of resembles a trilobite, or a segmented worm, or a possible relation to Dickinsonia. It looks like all sorts of animals but doesn’t really fit with anything known. It grew up to two inches long, or 5 cm, and had what’s referred to as a head shield although we don’t know for sure if it was actually its head. The head shield might have had eyes and might have had some kind of antennae, and some fossils seem to show a round mouth in the middle of the head, but it’s hard to tell. The rest of its body was segmented in rings. What Spriggina didn’t have was legs, or at least none of the fossils found so far show any kind of legs. Some species of Spriggina show a glide reflection body plan, while others appear to show a more ordinary bilateral body plan.

Three Ediacaran animals have such a weird body plan that they’ve been placed in their own phylum, Trilobozoa, meaning three-lobed animals. They show tri-radial symmetry, meaning that they have three sections that are identical radiating out from the center. They lived on microbial mats and were only about 40 mm across at most, which is about an inch and a half. Tribrachidium was roughly round in shape although its relations looked more like tiny cloverleaf rolls. Cloverleaf rolls are made by putting three little round pieces of dough together and baking them so that the roll has three lobes, although Trilobozoans probably didn’t taste as good. Also, Trilobozoans were covered with little grooves from center to edge and had three curved ridges, one on each lobe. The ridges were originally interpreted as arms or tentacles, but they seem to have just been ridges. Researchers think the little grooves directed water over the body’s surface and the ridges acted as tiny dams that slowed the water down just enough that particles of food carried in the water would fall onto the body so that the animal could absorb the nutrients, although we don’t know how that worked.

Many other Ediacaran animals had radial symmetry like modern echinoderms and jellyfish, including the ancestors of jellyfish. Some Ediacaran animals even had shells of various kinds, and they’re generally referred to as small shelly fossils. They were rarely more than a few millimeters across at most and are sometimes found mixed in with microbial mats. Cochleatina, for instance, is less than a millimeter across and all we know about it is that it had a ribbon-like spiral shell like a really simple snail’s shell. It wasn’t a snail, though. We don’t even know if it was an animal. It might have been some kind of algae or it might have been something else. Unlike most small shelly fossils, Cochleatina survived into the Cambrian period.

We’re also not sure why most Ediacaran organisms went extinct at the beginning of the Cambrian, but it’s probable that most were outcompeted by newly evolved animals. There may also have been a change in the chemical makeup of the ocean and atmosphere that caused an extinction event of old forms and allowed the rapid expansion of new animal forms that we call the Cambrian explosion.

We can also learn a lot about what we don’t find in the Ediacaran rocks. Pre-Cambrian animals didn’t appear to burrow into the sea floor, or at least we haven’t found any burrows, just tracks on the surface. Most Ediacaran animals also didn’t have armored bodies or claws or so forth. Researchers think that predation was actually pretty rare back then, with most animals acting as passive filter feeders to gather nutrients from the water, or they ate the microbial mats. It wasn’t until the Cambrian explosion that we see evidence that some animals evolved to kill and eat other animals exclusively.

With every new Ediacaran fossil that’s found and studied, we learn more about this long-ago time when multi-cellular life was brand new.

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 283: Crocodylomorphs and Friends

Thanks to Max and Pranav for their suggestions this week! We’re going to learn about some crocodylomorphs and a few other ancient non-dinosaur reptiles.

Further reading:

Mammal-like crocodile fossil found in East Africa, scientists report

Ancient crocodiles walked on two legs like dinosaurs

Fossil Footprints Help Uncover the Mysteries of Bipedal Crocodiles

Fossil mystery solved: super-long-necked reptiles lived in the ocean, not on land

Kaprosuchus had TEETH:

Anatosuchus earned its name “duck crocodile”:

Ancient bipedal croc footprints (picture taken from link above):

Tanystropheus had a super long neck:

Show transcript:

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

This week we’re going back in time to learn about some prehistoric reptiles that aren’t dinosaurs. Most are crocodylomorphs, which Pranav suggested a while back, but not all. Thanks to Pranav and Max for their suggestions this week! Max even made some clay models of two of these animals and sent me pictures, which was amazing! I have some really talented listeners.

Pranav and Max both wanted to know about kaprosuchus, also called the boar crocodile. The boar croc lived around 95 million years ago and probably grew nearly 20 feet long, or 6 meters, although all we know about it right now comes from a single nearly complete fossilized skull. The skull was found in Niger, a country in West Africa, and only described in 2009.

The boar croc gets its name from its teeth. It had lots of teeth, because it was a crocodyliform, although not actually an ancestral crocodile. It was related to modern crocs, though. Three sets of its teeth were especially long and large and projected out of its mouth much farther than ever found in any croc or croc relative, with one pair of teeth so big the upper jaw had little grooves for them to fit into so it could actually close its mouth. The teeth look like boar tusks, especially warthog tusks.

The boar croc also had some other differences from other croc relatives. The tip of its snout is unusually heavy, and some researchers think it might have had a keratin sheath over it. It might have used its heavy snout as a battering ram, possibly to stun prey before grabbing it with its huge teeth. It most likely hunted on land instead of in the water, since its eyes were lower on its head than crocs that hunt in water. Modern crocodiles and their relations mostly have eyes at the top of the head, which allows them to stay submerged except for their eyes. Whether it hunted in water or on land, though, the boar croc definitely killed and ate small dinosaurs, or maybe not so small dinosaurs.

The boar croc also had some horn-like projections on the back of its head. I don’t want to alarm you, because this animal went extinct millions and millions of years ago, but this thing was basically a dragon.

Anatosuchus was another crocodylomorph whose fossils have been found in Niger, but it’s much smaller and weirder than you’d expect. It was a tiny little thing, estimated to grow only a little more than 2 feet long, or 70 cm, and it was lightly built with relatively long legs for a croc relation, although it was still smaller than a cat. Its small teeth curve backwards but its snout has a little pointy projection at the front, although its head is broad and flat so that from above, its snout looks kind of like a duck’s bill. That’s why it’s sometimes called the duck crocodile. It lived around 145 million to 100 million years ago. Researchers think it may have waded in shallow water to catch small animals like fish and frogs, something like a heron.

Around 105 million years ago, another small croc relation lived in what is now Tanzania in East Africa. It was first discovered in 2008 and has been named Pakasuchus, which means cat crocodile. It was even smaller than the duck crocodile, only 20 inches long, or 50 cm, with long legs and a delicate build. The really weird thing, though, is its teeth. Unlike other crocodile relations and in fact unlike reptiles in general, it had teeth that were specialized for different functions. Its teeth looked like they belonged to a mammal. It had sharp teeth at the front of its short jaws and broader teeth in the back of its mouth that it used to chew its food. It was a terrestrial animal that would have been active and fast-moving. It probably ate insects and other small animals, but some researchers think it may have eaten plants.

There were definitely some croc relatives that were herbivorous, like the aetosaurs. Aetosaurs lived a little over 200 million years ago and were a successful group, with fossils found in Europe, India, Africa, and North and South America. They had osteoderms that are really common in the fossil record, so common that they’re used as index fossils to date fossil sites. If you’re not sure how old a layer of rock is, and you find some aetosaur osteoderms, you can be pretty certain you’re looking at the late Triassic. The osteoderms are flattened like big scales, and in fact when they were first discovered, people thought they were actually fish scales. Aetosaurs were probably terrestrial animals and most were either herbivorous or omnivorous, although at least one known species had the kind of teeth that indicate it hunted small animals.

A typical aetosaur had a small head and a bulky body with relatively small front legs but stronger hind legs. Its tail was long and tapering like a modern crocodile’s tail. It had lots of armor in the form of interlocking osteoderms, including armor on its belly and the underside of its tail. It might have looked like it had a carapace something like a weird reptilian armadillo. Depending on its species, our typical aetosaur may have also had spikes or spines on its back sort of like modern crocodiles have.

One species of aetosaur, Desmatosuchus spurensis, had massive shoulder spikes. Desmatosuchus grew almost 15 feet long, or 4.5 meters, and was heavily armored, with a spike on each shoulder blade. The spikes curved up and out kind of like a bull’s horns, but instead of pointing forward, they pointed backwards. It also had smaller spikes down its sides, some of which pointed out, some up. The big shoulder spikes could be almost a foot long, or 28 cm.

If you look at Desmatosuchus’s skeleton, it looked like it must have been a dangerous animal, and this would have been true when it comes to worms and plants. Its head was small and ended in a shovel-like snout, probably covered in a keratin sheath like a turtle’s beak. Scientists think it probably used its snout to dig plants up from soft mud along waterways, and it would probably also eat any small animals it found in the mud too. It lived in groups and despite its size and all its spikes, it got eaten a lot by an even bigger reptile, Postosuchus.

Postosuchus wasn’t a dinosaur, and was in fact a crocodylomorph just like the other reptiles we’ve talked about so far, but it sure looked like a dinosaur in a lot of ways. Its front legs were about half the length of and not very strong compared to its hind legs, so it probably walked on its hind legs only. It also had an oversized claw on one of its toes that it probably used to slash at prey, while its big head had a mouth full of big, sharp teeth. In other words, it looked a lot like a theropod dinosaur and lived at about the same time as the first theropods.

Despite not being a dinosaur, Postosuchus was one of the biggest land animals around, growing up to about 23 feet long, or 7 meters, although it probably only stood about 4 feet high, or 1.2 meters. Its remains have only been found in North America.

Other bipedal croc relations have been found in Asia, though, specifically in South Korea where almost 100 beautifully preserved footprints have been found. The tracks are of hind feet only, and from their size, depth, and the length of stride, the animals were probably almost 10 feet long, or 3 meters, and had hind legs the length of an average adult human’s legs. The footprints are almost 9 ½ inches long, or 24 cm.

At first researchers thought the tracks belonged to giant pterosaurs, which were flying reptiles, and that the pterosaurs were walking on their hind legs so their wings would stay out of the mud. But the footprints are so well preserved that it was obvious they belonged to a crocodylomorph once paleontologists examined them closely. In fact, all footprints supposed to belong to pterosaurs walking on their hind legs have turned out to belong to bipedal croc relations. Pterosaurs had to use their wings as front legs when walking on the ground, like bats do but not like birds, and some crocs, which ordinarily walk on four legs, were walking on two. It’s topsy-turvy land!

The tracks in South Korea are dated to a little over 113 million years ago, which is something like 100 million years more recent than Postosuchus. Postosuchus went extinct around 201 million years ago, at the end of the Triassic. By the time the Korean croc relation was walking around, it was the middle of the Cretaceous and dinosaurs ruled the earth. Gondwana was breaking up, the climate was warm worldwide and sea levels were high, mammals were tiny and unimportant, and little birds were flying around along with gigantic pterosaurs like Quetzalcoatlus. Crocodile relations lived in the mid-Cretaceous, sure, but not bipedal ones…or so paleontologists thought.

All we have of these croc relations are their tracks. We don’t have any fossils so we don’t know what they looked like. Hopefully one day some fossils will come to light and paleontologists will be able to match them up with their footprints.

Max specifically asked about Titanoboa, a gigantic extinct snake that lived around 58 million years ago in what is now northern South America. We talked about Titanoboa in episode 197 but I was certain I could find some new information for this episode. Unfortunately, there haven’t been any new studies about Titanoboa published recently, so Max, I’m going to keep it on the suggestions list until I find some interesting new information to share.

Titanoboa is estimated to have grown as much as 42 feet long, or 13 meters, and it probably spent most of its time in the water, eating giant lungfish and other animals. But, to wrap things back around to crocodylomorphs, it probably also ate a croc relation called Cerrejonisuchus. Cerrejonisuchus had a short, narrow snout and probably ate lots of frogs, fish, and other small animals. It grew a little over 7 feet long, or 2.2 meters, which is small but respectable for a crocodile but nowhere near big enough to make Titanoboa think twice about eating it. It wasn’t even the biggest croc relation living in its river habitat. Acherontisuchus grew to an estimated 21 feet long, or almost 6.5 meters. It had a long snout and lots and lots of big teeth, and probably ate the same fish that Titanoboa also liked.

Let’s finish with a non-crocodylomorph ancient reptile, Tanystropheus, and two mysteries associated with it that science solved in 2020. Tanystropheus lived during the mid to late Triassic, around 240 million years ago, and its fossils have been found in parts of Europe, the Middle East, and in China. It grew up to 20 feet long, or 6 meters, but literally half its length was its incredibly long neck.

When the first Tanystropheus fossils were discovered in the 19th century, paleontologists didn’t know what it was. There were some long, thin bones associated with the skeleton and they thought those might be elongated finger bones. Tanystropheus was classified as a type of pterosaur. But as more and better fossils were discovered, it was obvious that this animal wasn’t flying anywhere. The finger bones were actually cervical ribs, rod-like structures that helped stabilize the long neck and keep it from bending very far.

Tanystropheus was reclassified as a long-necked reptile, but no one was sure if it lived in water or just around water. Even more confusing, fossils of smaller long-necked reptiles, only about 4 feet long, or 1.2 meters, started being found too. No one was sure if this was a different species or juvenile Tanystropheus specimens.

To solve the first mystery, a research team took CT scans of some complete but crushed Tanystropheus skulls and generated a 3D image, which allowed them to put the pieces together and examine an image of a complete, un-crushed skull.

The skull had nostrils at the top of its snout, indicating that it probably spent a lot of time in the water. Some researchers suggest it was an ambush predator in shallow water, resting on the bottom of the ocean with its long neck raised so its nostrils were just above the surface. When a fish or other animal swam by, it could grab it without needing to move more than its head. Since its body was chonky with short legs, it probably wasn’t a very fast mover.

Next, the team took cross sections of bones from the smaller long-necked reptile and examined them for growth rings. They found a lot of them, indicating that the animals weren’t juvenile Tanystropheus hydroides, they were adults of another species, which has been named Tanystropheus longobardicus. The two species also had differently shaped teeth, which suggests that they were eating different types of food.

Even though Tanystropheus’s neck was really long, it was also much lighter than the rear half of its body, which had strongly muscled hind legs. Some researchers think it swam by kicking its hind legs sort of like a gigantic frog’s. We have some fossilized trackways from a shallow marine environment that show paired prints from hind legs, but no front leg prints, which may be from a small species of Tanystropheus.

There’s still a lot we don’t know about Tanystropheus, just as there’s a lot we don’t know about a lot of long-extinct animals. All we know for sure is that they were awesome.

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. There are links in the show notes to join our mailing list and to our merch store.

Thanks for listening!

Episode 282: Little Longtailed Birds

Sign up for our mailing list!

Thanks to Elaine for suggesting one of our long-tailed birds this week!

Happy birthday to Jasper!! Have a great birthday!

Further reading:

Fossil of Ancient Long-Tailed Bird Found in China

All adult scissor-tailed flycatchers have long tails:

The long-tailed sylph male is the one with the long tail:

The long-tailed widowbird male has a long tail:

The long-tailed widowbird female has a short tail:

The pin-tailed whydah male has a long tail:

A pin-tailed whydah baby (left) next to a common waxbill baby (right):

Kompsornis longicaudus had a really long tail:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week is a short episode all about little birds with really long tails. The tails are longer than the episode. Thanks to Elaine for suggesting one of the birds we talk about today!

But before we start learning about birds, we have a birthday shout-out! Happy birthday to Jasper, who has the best name and who will hopefully have the best birthday to go along with it!

Let’s start with Elaine’s suggestion, the scissor-tailed flycatcher. I’m embarrassed to admit that Elaine suggested this bird way back in 2020, so it’s about time we talked about it.

The scissor-tailed flycatcher lives in south-central North America during the summer, especially Texas and Oklahoma, and migrates to parts of Mexico and Central America in winter. It’s pale gray with black and white wings and tail, and salmon pink markings on its sides and under its wings. It also has a really long tail. It gets the name scissor-tail because its tail is so long and forked that it’s sort of the shape of an open pair of scissors. The male’s tail is typically longer than the female’s, longer than the rest of its body. The bird is about the size of an average songbird, with a body length of about 5 inches, or 13 centimeters, but with a tail that can increase its overall length to over 14 inches, or 36 cm.

The scissor-tailed flycatcher prefers open areas like pastures and fields, where there’s lots of space but some brush, trees, or fences nearby to perch in. It mostly eats insects, but it will also eat berries, especially in winter. It’s related to kingbirds and pewees and will even hybridize with the western kingbird where their ranges overlap. Its long tail is partly for display, but mostly it helps the bird maneuver in midair as it chases insects, or hover in midair as it looks around for an insect to catch. It especially likes grasshoppers, and when it catches one, it will usually kill it before eating it by smashing it against a tree limb or other perch.

Another little bird with a long tail is the long-tailed sylph, which is a type of hummingbird! It lives on the eastern slopes of the Andes Mountains in northwestern South America, mostly along forest edges, in gardens, grasslands, and other mostly open areas. It migrates to different parts of the mountains at different times of year to follow the flowering of its favorite plants. It’s larger than many species of hummingbird even if you don’t count the tail.

It eats nectar like other hummingbirds do, but also eats tiny insects and spiders. Its bill is black and not very long compared to most of its relations. Sometimes it will jab the tip of its bill straight through the base of a flower to get at the nectar, instead of inserting it into the flower like other hummingbirds do, and while it can hover, sometimes it perches to feed instead.

Both the male and female long-tailed sylph are a beautiful metallic blue and green in color, although the male is brighter and has purplish-brown wings. The female is about 4 inches long, or 10 cm, including her tail, and while the male is about the same size as the female, his tail is really long—up to 4.5 inches long, or 12 cm. His tail is forked like the scissor-tailed flycatcher’s, but unlike the flycatcher, the sylph’s tail makes it harder for the bird to fly. During breeding season the male attracts a mate by flying in a U-shaped pattern that shows off his tail and his flying ability.

The male long-tailed widowbird also attracts a mate with a flying display to show off his long tail. It lives in grasslands in a few parts of Africa, with the biggest population in South Africa. It forages in small flocks looking for seeds, and it also eats the occasional insect or spider. It’s a sparrow-like bird only about 4 inches long, or 10 cm, not counting its tail. The female is mostly brown with darker streaks and has a short tail. The male is black with red and white patches on the shoulders of his wings, called epaulets. His coloring, including the epaulets, is almost identical to that of a totally unrelated bird, the red-winged blackbird of North America, but he has something the blackbird doesn’t: a gigantically long tail.

The male widowbird’s tail is made up of twelve feathers, and about half of them grow up to 20 inches long. That’s nearly two feet long, or half a meter. Like the long-tailed sylph, the long-tailed widowbird’s tail actually makes it harder for him to fly. If it’s raining, he can’t fly at all. Fortunately for him, outside of the breeding season his tail is much shorter. During display flights, he spreads his tail feathers to show them off better and flies very slowly. Males with the longest tails attract the most females.

Similarly, the pin-tailed whydah is another little sparrow-like bird where the male grows a really long tail to attract females. It lives in grasslands, savannas, and open woodlands in sub-Saharan Africa, which just means south of the Sahara Desert. It mostly eats seeds.

During breeding season, the male is a striking pattern of black and white with a bright orangey-red bill and really long tail plumes. He’s about the size of the long-tailed widowbird but his tail grows about 8 inches long, or 20 cm. The female is brown with darker streaks and looks a lot like a sparrow, although it’s not related to sparrows. To impress a female, the pin-tailed whydah will hover in place near her, showing off his long tail plumes and his flying ability.

A lot of whydah species grow long tails. A lot of whydahs are also brood parasites, including this one, meaning that instead of building a nest and taking care of her own eggs, the female sneaks in and lays her eggs in the nest of a different species of bird. Then she flies away, probably whistling to make her seem extra nonchalant, and leaves the other bird to take care of her eggs and the babies when they hatch. She mostly lays her eggs in the nests of various species of finch, and not only do her eggs resemble the finch’s eggs except that they’re bigger, the babies resemble finch babies when they hatch, except they’re bigger.

Specifically, the babies have a really specific gape pattern. When an adult bird approaches its nest, a baby bird will gape its mouth wide to beg for food. This prompts the parent bird to shove some food down into that mouth. The more likely a baby is to be noticed by its parent, the more likely it is to get extra food, so natural selection favors babies with striking patterns and bright colors inside their mouths. Many finches, especially ones called waxbills, have a specific pattern of black and white dots in their mouths that pretty much acts as a food runway. Insert food here. The whydah’s mouth gape pattern mimics the waxbill’s almost exactly. But as I said, the whydah chick is bigger, which means it can push the finch babies out of the way and end up with more food.

The pin-tailed whydah is a common bird and easily tamed, so people sometimes keep it as a pet. This is a problem when it’s brought to places where it isn’t a native bird, because it sometimes escapes or is set free by its owners. If enough of the birds are released in one area, they can become invasive species. This has happened with the pin-tailed whydah in many parts of the world, including parts of Portugal, Singapore, Puerto Rico, and most recently southern California. Since they’re brood parasites, they can negatively impact a lot of other bird species in a very short time. But a study released in 2020 about the California population found that they mostly parasitize the nests of a bird called the scaly-breasted munia, a species of waxbill from southern Asia that’s been introduced to other places, including southern California, where it’s also an invasive species. So I guess it could be worse.

There are lots of other birds with long tails we could talk about, way too many to fit into one episode, but let’s finish with an extinct bird, since that seems to be the theme lately. In May 2020, an ancient bird was described as Kompsornis longicaudus, and it lived 120 million years ago in what is now China. Its name means long-tailed elegant bird. It was bigger than the other birds we’ve talked about today, a little over two feet long, or 70 cm, but a lot of that length was tail.

Kompsornis is only known from a single fossil, but that fossil is amazing. Not only is it almost a complete skeleton, it’s articulated, meaning it was preserved with all the body parts together as they were in life, instead of the bones being jumbled up. That means we know a lot about it, including the fact that unlike other birds of the time, it didn’t appear to have any teeth. It also shows other features seen in modern birds but not always found in ancient birds, including a pronounced keel, which is where wing muscles attach. That indicates it was probably a strong flier. It also had a really long tail, but unlike modern birds its tail was bony like a lizard’s tail although it was covered with feathers.

During their study of Kompsornis, the research team compared it to other birds in the order Jeholornithiformes, which seem to be its closest relations. There were six species known, with Kompsornis making a seventh—except that during the study, the team discovered that one species was a fake! Dalianraptor was also only known from one fossil, and that fossil was of a different bird with the arms of a flightless theropod added in place of its missing wings. Send that fossil to fossil jail!

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 that way.

Thanks for listening!

Episode 281: The Humpback Whale

Thanks to Clay for suggesting the topic of this week’s episode, the humpback whale!

Happy birthday to Emry!

Further reading:

How humpback whales catch prey with bubble nets

Study: Humpback whales aren’t learning their songs from one another

Stanford researchers observe unexpected flipper flapping in humpback whales

Ancient baleen whales had a mouthful

The humpback’s long, thin flippers help it maneuver:

Humpbacks are active, jumpy whales:

A humpback whale’s big mouth:

Show transcript:

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

Thanks to Clay for suggesting this week’s topic, the humpback whale!

But first, we have a birthday shout-out! A great big happy birthday to Emry! I hope your birthday is so epic that in the future, when people look up birthday in the dictionary, your name is listed there.

I’m amazed we haven’t talked about the humpback whale before because when I was little, it was my favorite whale until I learned about the narwhal. Sorry, humpback, you’re now my second favorite whale.

The humpback is a baleen whale, specifically a rorqual, which is a group of related baleen whales. I don’t think I’ve mentioned the term rorqual before because I find it really hard to pronounce. Rorquals are long, slender whales with throat pleats that allow them to expand their mouths when they gulp water in. We talked about this in episode 211 about the fin whale, which is another rorqual. I’ll quote from that episode to explain again what the throat pleats are.

A baleen whale eats tiny animals that it filters out of the water through its baleen plates, which are keratin structures in its mouth that take the place of teeth. The baleen is tough but thin and hangs down from the upper jaw. It’s white and looks sort of like a bunch of bristles at the end of a broom. The whale opens its mouth wide while lunging forward or downward, which fills its huge mouth with astounding amounts of water. As water enters the mouth, the skin stretches to hold even more, until the grooves completely flatten out.

After the whale fills its mouth with water, it closes its jaws, pushing 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 can then swallow all that food and open its mouth to do it again. This whole operation, from opening its mouth to swallowing its food, only takes six to ten seconds.

The humpback mostly eats tiny crustaceans called krill, and little fish. Since gulp feeding takes a lot of energy, finding a lot of food in a relatively small space is important to the whale. Many little fish that live in schools will form what are called bait balls when they feel threatened, where the fish swim closer together and keep moving around. Any given individual fish has a good chance of avoiding being eaten when behaving this way. Think about last week’s episode, where the spinner shark swims straight up through a bait ball, biting biting biting. It eats some fish, but most are fine. But a big filter feeder like the humpback can gulp a whole lot of fish at once, so it really likes bait balls.

To help maneuver prey animals into a small area, groups of humpbacks sometimes employ a strategy called bubble-net feeding. The whales will dive below the fish or krill and swim in a ring, blowing bubbles the whole time. The bubbles startle the animals, who move away from them. But since the bubbles are all around them, and the whales swim closer and closer together so that the ring of bubbles shrinks, eventually the fish or krill are all clustered in a small space as though they’re caught in a net. Then the whales open their mouths and gulp in lots of food. This is actually a simplified explanation of how bubble-net feeding works, which requires several different types of bubbles and various actions by the whales to make it work right.

The humpback is closely related to the fin whale and the blue whale. In episode 211 we learned that fin and blue whales sometimes interbreed and produce offspring, and in at least one case a marine biologist identified a whale that appeared to be the hybrid of a blue whale and a humpback.

The humpback grows up to 56 feet long, or 17 meters, with females being a little larger than males on average. It’s mostly black in color, with mottled white or gray markings underneath and on its flippers. Its flippers are long and narrow, which allows it to make sharp turns. It also has tubercles on its jaws and the fronts of its flippers which are probably sensory organs of some kind, since they contain nerves attached to a very thin hair in the middle that’s about an inch long at most, or almost 3 cm.

This is a good time to remind you that even though they look very different from other mammals, all whales are mammals. Mammals are warm-blooded animals that produce milk for their babies. Mammals also have hair, unless they don’t have hair, except that the humpback whale does have hairs in its tubercles. So there you go, humpback whales have hair.

Despite its huge size, the humpback is an active whale. It frequently breaches, meaning it rises up out of the water almost its full length, then crashes back down into the water with a huge splash. It also often slaps its flippers or its tail on the surface. Some researchers think these behaviors may have something to do with communication with other whales, or that the whale is trying to get rid of parasites, or that the whale is just having fun.

Humpback whales are famous for their elaborate songs, which are produced by males. The whales breed in winter, and the males start singing as winter gets closer, so the songs must have something to do with mating season. Scientists aren’t sure what, though. Females don’t seem to be very interested in individual males who are singing, but they will sometimes be attracted to a group of singing males. Some researchers suggest that singing might be a general call to attract all whales in the area to the breeding grounds. Then again, sometimes a male will interrupt another male who is singing and the two will fight.

The songs vary and new song elements can spread quickly through a population. Generally, researchers think males hear a new element and incorporate it into their own songs, but results of a study published in 2021 found that similar new song elements often show up in whales that could not have heard other whales sing it. This indicates that instead of copying other songs, each whale modifies his own song individually and sometimes the changes are similar. That’s just one study, though. It’s probable that the way males change their songs depends on many factors, only one of which is hearing and imitating other songs.

The study suggests that the way we think about whale songs might be wrong to start with. Researchers generally think that a whale probably sings for the same reasons that birds sing: to stake out a territory, to advertise to potential mates that it’s healthy enough to spend energy singing, and to warn rivals away. But because whales live in an environment so different from birds, and so different from what we as humans understand, it’s possible that whalesong carries meanings and intentions that we can’t interpret. A different study published in 2019 discovered that male humpbacks sometimes sing in feeding grounds, especially when a population of whales decides to overwinter at their feeding grounds instead of migrating, as sometimes happens.

What, precisely, a whale’s song means to other whales is something that only the whales know for sure. This is what a humpback song sounds like:

[humpback song]

Humpbacks make other sounds other than songs, though. Mothers and calves need to communicate so that the calves get the care they need and don’t stray too far away, but since any sounds could attract predators, they have to communicate very quietly. They make little grunting sounds to each other.

The main predator of the humpback whale is the orca, which will attack and kill calves and sometimes even adults. As a result, the humpback really does not like orcas. Humpbacks will sometimes protect seals and other animals from orca attacks.

Humpbacks migrate from their summer habitats in either the Antarctic or the Arctic, depending on what hemisphere they live in, to their winter breeding grounds in tropical waters. Then they return to colder waters in summer where there’s more food, since krill is a cold-water species. These migrations can be as long as 5,000 miles, or 8,000 kilometers. Unlike some animals that migrate in huge herds, humpbacks mostly travel in small groups that are often widely spaced.

The humpback was almost driven to extinction by commercial whaling, but after it was declared a protected species, its numbers have increased. It still has the same human-caused dangers that many other marine animals face, including habitat loss and water pollution, climate change, drowning after being entangled in nets, and noise pollution that can keep whales from communicating.

There’s always a lot we don’t know about any given species of whale, since whales are hard to study. For instance, a 2017 study discovered that humpbacks sometimes swim in a way never documented in whales before. Whales swim by flexing their massively powerful tails, and use their flippers to maneuver. Think of the tail as the engine of a car and the flippers as the power steering system. The humpback’s flippers are uniquely shaped, which as we mentioned earlier means it can maneuver skillfully, turning much more quickly than a great big whale would otherwise be able to turn. But in video studies of whales in the wild, very rarely a whale would flap its flippers like a bird flapping its wings—or, more accurately, like a seal or sea lion swimming with its flippers. The researchers who analyzed the videos suggest that the flapping is used for accelerating quickly, and because it takes a lot of energy, the whales don’t do it often. The researchers also think the humpback may be the only whale species that can accelerate using the motion of its flippers, since other whales have much smaller flippers relative to their size.

As far as we know, baleen whales don’t use sonar the way toothed whales do. Their songs and sounds are for communication, not navigation. But while humpbacks mostly hunt for food near the surface of the water where there’s plenty of light, they do occasionally dive deeper and hunt for food near the bottom. They especially like an eel-like fish called the sand lance, which spends a lot of time buried in the sand on the sea floor. In 2014, a study of humpbacks diving to find these fish indicated that when a whale dives alone, it remains silent, but when it dives to hunt with some friends, they communicate with a sound described as a tick-tock. Not the app, just a sound like the ticking of a clock. Sometimes more humpbacks come to join the whales when they hear their tick-tock sounds. But we still don’t know how the whales find the fish in the first place, since there’s no light for them to hunt by. It’s possible they can detect the fish’s chemical signature in the water when they’re close enough to one.

Baleen whales don’t have teeth, although when a baby whale is developing in its mother’s womb it does grow teeth. But at some point during its development, these embryonic teeth are reabsorbed and baleen plates form instead.

The extinct ancestors of modern baleen whales still had teeth. One genus was called Aetiocetus, which lived between about 34 and 23 million years ago in the north Pacific Ocean. It probably wasn’t directly related to modern whales, since baleen whales do actually appear in the fossil record before Aetiocetus. It was a small whale that probably only grew about 11 feet long, or 3.5 meters, although some species might have grown twice that length. The first Aetiocetus fossils were discovered in the 1960s and it was initially described as a toothed whale, since it had teeth.

But not everyone agreed. Aetiocetus showed some adaptations to filter feeding seen in modern baleen whales. For instance, its lower jaw bones weren’t fused at the chin end as they are in toothed whales. Modern baleen whales don’t have connected lower jaw bones, and in fact they have a sensory organ at that spot that scientists think helps the whale keep from engulfing too much water and hurting itself.

Recently, a team of scientists examined a CT image of a skull of Aetiocetus weltoni and discovered something surprising. Baleen is made of keratin, and keratin is only preserved in fossils very rarely, but in baleen whale fossils, the upper jawbones do show grooves where the baleen once connected. These grooves were present in the Aetiocetus skull, even though it also had teeth.

Researchers think Aetiocetus may have used its teeth to filter larger fish from the water the way some animals like crab-eater seals do today. Its teeth interlocked, which would allow it to trap fish in its mouth while pushing water out between its teeth. Its baleen probably helped catch smaller fish and other animals. The baleen was far enough away from the teeth that the whale would have still been able to bite at fish and other prey without accidentally biting its own baleen. But, as the researchers mention in their 2021 paper, Aetiocetus had a really crowded mouth.

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 280: Lesser-Known Sharks

Thanks to Tobey and Janice this week for their suggestions of lesser-known sharks!

Further reading/watching:

CREATURE FEATURE: The Spinner Shark [this site has a great video of spinner sharks spinning up out of the water!]

Acanthorhachis, a new genus of shark from the Carboniferous (Westfalian) of Yorkshire, England

150 Year Old Fossil Mystery Solved [note: it is not actually solved]

The cartoon-eyed spurdog shark:

The spinner shark spinning out of the water:

The spinner shark not spinning (photo by Andy Murch):

A Listracanthus spine:

Show transcript:

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

This week we’re going to learn about three sharks you may have never heard of before! The first was suggested by my aunt Janice and the second by listener Tobey. The third is a mystery from the fossil record.

You may have heard about the findings of a study published in November of 2021, with headlines like “Venomous sharks invade the Thames!” My aunt Janice sent me a link to an article like this. Nobody is invading anything, though. The sharks belong where they are. It was their absence for decades that was a problem, and the study discovered that they’re back.

The Thames is a big river in southern England that empties into the North Sea near London. Because it flows through such a huge city, it’s pretty badly polluted despite attempts in the last few decades to clean it up. It was so polluted by the 1950s, in fact, that it was declared biologically dead. But after a lot of effort by conservationists, fish and other animals have moved back into the river and lots of birds now visit it too. It also doesn’t smell as bad as it used to. One of the fish now found again in the Thames is a small shark called the spurdog, or spiny dogfish.

The spurdog lives in many parts of the world, mostly in shallow water just off the coast, although it’s been found in deep water too. A big female can grow almost three feet long, or 85 cm, while males are smaller. It’s a bottom dweller that eats whatever animals it finds on the sea floor, including crabs, sea cucumbers, and shrimp, and it will also eat jellyfish, squid, and fish when it can catch them. It’s even been known to hunt in packs.

It’s gray-brown in color with little white spots, and it has large eyes that kind of look like the eyes of a cartoon shark. It also has a spine in front of each of its two dorsal fins, which can inject venom into potential predators. The venom isn’t deadly to humans but would definitely hurt, so please don’t try to pet a spurdog shark. If the shark feels threatened, it curls its body around into a sort of shark donut shape, which allows it to jab its spines into whatever is trying to grab it.

The spurdog used to be really common, and was an important food for many people. But so many of them were and are caught to be ground into fertilizer or used in pet food that they’re now considered vulnerable worldwide and critically endangered around Europe, where their numbers have dropped by 95% in the last few decades. It’s now a protected species in many areas.

The female spurdog retains her fertilized eggs in her body like a lot of sharks do. The eggs hatch inside her and the babies develop further before she gives birth to them and they swim off on their own. It takes up to two years before a pup is ready to be born, and females don’t reach maturity until they’re around 16 years old, so it’s going to take a long time for the species to bounce back from nearly being wiped out. Fortunately, the spurdog can live almost 70 years and possibly longer, if it’s not killed and ground up to fertilize someone’s lawn. The sharks like to give birth in shallow water around the mouths of rivers, where the water is well oxygenated and there’s lots of small food for their babies to eat, which is why they’ve moved back into the Thames.

Next, Tobey suggested we talk about the spinner shark. It’s much bigger than the spurdog, sometimes growing as much as 10 feet long, or 3 meters. It lives in warm, shallow coastal water throughout much of the world. It has a pointy snout and is brown-gray with black tips on its tail and fins, and in fact it looks so much like the blacktip shark that it can be hard to tell the two species apart unless you get a really good look. It and the blacktip shark also share a unique feeding strategy that gives the spinner shark its name.

The shark eats a lot of fish, especially small fish that live in schools. When the spinner shark comes across a school of fish, it swims beneath it, then upward quickly through the school. As it swims it spins around and around like an American football, but unlike a football it bites and swallows fish as it goes. It can move so fast that it often shoots right out of the water, still spinning, up to 20 feet, or 6 meters, before falling back into the ocean. The blacktip shark sometimes does this too, but the spinner shark is an expert at this maneuver.

There’s a link in the show notes to a page where you can watch a video of spinner sharks spinning out of the water and flopping back down. It’s amazing and hilarious. Tobey mentioned that the spinner shark is an acrobatic shark, and it certainly is! It’s like a ballet dancer or figure skater, but with a lot more teeth. And fewer legs.

Because spinner sharks mainly eat fish, along with cephalopods, they almost never attack humans because they don’t consider humans to be food. Humans consider the spinner shark food, though, and they’re listed as vulnerable due to overhunting and habitat loss.

We’ll finish with a mystery shark. I’ve had Listracanthus on my ideas list for a couple of years, hoping that new information would come to light, but let’s go ahead and talk about it now. It’s too awesome to wait any longer.

We know very little about Listracanthus even though it was around for at least 75 million years, since it’s an early shark or shark relative with a cartilaginous skeleton. Cartilage doesn’t fossilize very well compared to bone, so we don’t have much of an idea of what the shark looked like. What we do have are spines that grew all over the fish and that probably made it look like it was covered with bristles or even weird feathers. The spines are a type of denticle that could be up to 4 inches long, or 10 cm. They weren’t just spines, though. They were spines that had smaller spines growing from their sides, sort of like a feather has a main shaft with smaller shafts growing from the sides.

The spines are fairly common in the fossil record from parts of North America, dating from about 326 million years ago to about 251 million years ago. Listracanthus was closely related to another spiny shark-like fish, Acanthorhachis, whose spines have been found in parts of Europe and who lived around 310 million years ago, but whose spines are less than 3 inches long at most, or 7 cm.

Some researchers think the spines were only present on parts of the shark, maybe just the head or down the back, but others think the sharks were covered with the spines. Many times, lots and lots of the spines are found together and probably belong to a single individual whose body didn’t fossilize, only its spines. Some researchers even think that the flattened denticles from a shark or shark relation called Petrodus, which is found in the same areas at the same times as Listracanthus, might actually be Listracanthus belly denticles.

The spines probably pointed backwards toward the tail, which would reduce drag as the fish swam, and they might have been for display or for protection from predators, or of course both. The main parts of the spine were also hollow and there’s evidence there were capillaries inside, so they might have had a chemosensory or electrosensory function too.

Modern sharks have denticles that make their skin rough, sort of like sandpaper. One modern shark, the sandy dogfish, Scyliorhinus canicula, which is common in shallow water off the coasts of western Europe and northern Africa, and in the Mediterranean, has especially rough denticles on its tail. They aren’t precisely spines, but they’re more than just little rough patches. The sandy dogfish is a small, slender shark that barely grows more than about three feet long, or about a meter, and it eats anything it can catch. Young dogfish especially like small crustaceans, and sometimes they catch an animal that’s too big to swallow whole. In that case, the shark sticks the animal on the denticles near its tail, which anchors it in place so it can tear bite-sized pieces off. Some other sharks do this too, so it’s possible that Listracanthus and its relations may have used its spines for similar behavior.

We don’t know much about these sharks because all we have are their spines. Only one probable specimen has been found, by a paleontologist named Rainer Zangerl. Dr. Zangerl found the remains of an eel-like shark in Indiana that was covered in spines, but unfortunately as the rock dried out after being uncovered, the fossil literally disintegrated into dust.

In August of 2019, a fossil hunter posted on an online forum for fossil enthusiasts to say he’d found a Listracanthus specimen. He posted pictures, although since the fossil hasn’t been prepared it isn’t much to look at. It’s just an undulating bump down a piece of shale that kind of looks like a dead snake. Fortunately, the man in question, who goes by RCFossils, knew instantly what he’d found. He also knew better than to try to clean it up himself. Instead, he’s been working on trying to find a professional interested in taking the project on. In May of 2022 he posted again to say he’d managed to get an X-ray of the fossil, which shows a backbone but no sign of a skull. He’s having trouble finding anyone who has the time and interest in studying the fossil, but hopefully he’ll find someone soon and we’ll all learn more about this mysterious pointy shark.

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 279: Mean Piggies

Thanks to Molly for suggesting andrewsarchus and entelodont, our mean “piggies” we learn about this week!

Further reading:

Andrewsarchus, “Superb Skull of a Gigantic Beast”

Dark Folklore by Mark Norman and Tracey Norman

Further listening:

The Folklore Podcast

Andrewsarchus (taken from article linked above):

Andrewsarchus’s skull. I’m not sure who the guy holding it is, but I like to think his name is Andrew:

Entelodont:

Show transcript:

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

I’m getting really backed up on listener suggestions, so over the next few months I plan to cover as many of them as possible. We’ll start with two suggestions by Molly, who wanted to learn about Andrewsarchus and the related Entelodont. We talked about entelodonts briefly back in episode 116, and if you remember that episode, you may remember that entelodonts are sometimes referred to as the terminator pig or the hell pig. So yes, we are going to learn about some mean piggies this week, with a bonus fun mystery piggy at the end.

Andrewsarchus mongoliensis lived in what is now central Asia about 42 million years ago. It’s only known from a single skull found in 1923 in Inner Mongolia, which is part of China these days. The skull has a long snout and is big and wide, over 2.5 feet long, or 83 cm. It has huge, strong teeth that look ferocious.

When the skull was first found, some paleontologists on the team thought it was from a huge wolf-like carnivore. But others weren’t so sure. They thought it was the skull of a pig relative, and pigs are omnivores. Without more fossil remains, we can’t know for sure what Andrewsarchus’s body looked like, but these days scientists mostly think it was closely related to entelodonts.

Despite being called the terminator pig, entelodonts weren’t very closely related to pigs, although they and Andrewsarchus are in the order Artiodactyla. That’s the order that includes all even-toed hoofed mammals and their close relations, including pigs, but also including hippos and whales. Hippos and whales are actually pretty closely related, and entelodonts and Andrewsarchus were more closely related to hippos than to pigs.

Daeodon [DIE-oh-don] was the biggest entelodont known, and it may have stood up to 7 feet tall at the shoulder, or just over 2 meters. It lived in North America, but there was another species from Eurasia, Paraentelodon intermedium, that was probably close to the same size. Both lived about 22 million years ago.

Entelodonts had big, wide skulls with flared cheekbones and knob-like bony protrusions, so its head may have looked something like a warthog’s head. It also had cloven hooves. We don’t know if Andrewsarchus had hooves since we haven’t found anything but that one huge skull. The larger species of Entelodont had a humped shoulder something like a bison for the attachment of strong neck muscles to support the head’s weight, and Andrewsarchus probably had this too. The rest of the body was much more lightly built, with short, slender legs and a skinny little tail.

Even though Entelodont teeth are fearsome-looking, and at least some species of Entelodont were probably active hunters, they’re considered omnivores and Andrewsarchus probably was too. In fact, because Andrewsarchus was found on what was once a beach along the ocean, some researchers think it might have used its big forward-pointing front teeth to dig shellfish out of the sand. Most likely it ate pretty much anything it could find or catch, including shellfish, turtles, and other small animals, carrion, and plant material like fruit, nuts, and roots.

The teeth of some entelodont species show wear marks that indicate it probably bit through bones pretty frequently, possibly while scavenging already dead animals but possibly also when killing prey. One fossil skull of a herbivorous artiodactyl that lived in North America was found with an entelodont incisor embedded in it.

On the other hand, we have a set of fossil tracks in Nebraska, in the United States, that shows the behavior of what may have been an entelodont called Archaeotherium. Archaeotherium lived around 30 million years ago and grew up to 5 feet tall at the shoulder, or 1.5 meters, although most specimens found were closer to 4 feet tall, or 1.2 meters. The fossil tracks are from three animals: a type of rhinoceros, a predator of some kind, possibly the hyena-like Hyaenodon, and a species of Archaeotherium. The rhinoceros tracks show that it was walking along, then suddenly took off at a run. The Hyaenodon tracks are nearby and possibly indicate pursuit of the rhino, or it might have just happened to be nearby and frightened the rhino. The Archaeotherium tracks, meanwhile, zigzag back and forth. What on earth is going on with that?

Entelodonts had a very good sense of smell, much like pigs do, and walking in a zigzag pattern would allow Archaeotherium to smell things more efficiently. Some researchers suggest it might have been keeping an eye on the rhino hunt, and that if the Hyaenodon managed to bring down its prey, Archaeotherium might have decided to chase Hyaenodon away from its kill. It might also have been waiting for one or both animals to become tired, and then it could attack. Then again, it might just have been looking for some yummy fruit to eat. While some places online will tell you Archaeotherium was hunting the rhino, that’s not what the tracks indicate.

Entelodonts could open their mouths really, really wide. If you’ve ever seen a hippo with its humongous mouth open, that’s what we’re talking about here. Male hippos sometimes fight by jaw-wrestling each other, and researchers think entelodonts might have done something similar. A lot of entelodont skulls show healed puncture wounds in places consistent with jaw-wrestling. The knobby protrusions on its skull might have been an adaptation to this behavior, with thickened skin over them to keep a rival’s teeth from biting too deeply. This is the case with some pigs with similar skull protrusions, which we talked about in episode 128. The head bite wounds are only seen in adult animals, and younger animals didn’t have the massive cheek and jaw muscles seen in adults.

The big question is whether Andrewsarchus was actually an entelodont or just closely related to the entelodonts. That’s the same thing paleontologists have been discussing for the last century. Until we find more Andrewsarchus fossils, though, there’s only so much we can determine about the animal, including how similar it was to the entelodonts. For instance, while entelodonts did have cloven hooves, the two halves of the hoof could spread apart like fingers, which is similar to the way camel feet are structured. This would have helped it walk on soft ground, like sand or mud. If Andrewsarchus turns out to have similar feet, it was probably an entelodont.

Finding more Andrewsarchus remains will allow us to get a good idea of how big it could grow, too. Estimates based on the same proportions seen in entelodonts suggest it might have stood about 6 feet tall at the shoulder, or 1.8 meters.

As we’ve established, entelodonts and Andrewsarchus weren’t actually pigs, although they probably looked a lot like weird oversized warthogs with some features seen in wild boars. There’s no evidence they had a pig-like snout, called a nasal disk, which is flattened at the end. Entelodonts had nostrils on the sides of the snout, something like a horse’s nostrils.

But let’s finish with an actual pig, the mystery of the sewer pig. I got this information from a fantastic book called Dark Folklore by Mark and Tracey Norman, and I read the book because I listen to The Folklore Podcast, which is by folklorist Mark Norman, although I think Tracey Norman helps out with it too. I’ll just quote from the book, and definitely check the show notes for a link if you want to order your own copy.

“Foreshadowing the 1980s panic about baby alligators being taken home as pets and subsequently flushed down the toilet into the sewer system of New York, 1859 London was overtaken by a panic about the Sewer Pigs of Hampstead.

“The sewer pigs were thought to be a monstrous porcine family living entirely below ground in the London sewer system, and even featured in the Daily Telegraph newspaper. A sow had apparently become trapped, it was said, and had given birth to a litter of piglets, the entire family living off the rubbish that accumulated in the sewers and producing litter after litter. The population lived in fear of these terrible creatures escaping from the sewer system and running riot throughout London.

“Obviously, there is nothing within a sewer system that would sustain a pig, let alone a number of them. The fear connected to this particular urban legend is disease and it arose after the hot summer of 1858 caused a devastating outbreak of typhoid and cholera in the city. Unsurprisingly, there has never been any evidence of pigs in London’s sewers, monstrous, lost or otherwise.”

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 277: Rewilding Scotland

This week is Caitie Sith and Dave’s episode! They want to learn about animals reintroduced to Scotland, especially the Highland wildcat!

The Scottish (or Highland) wildcat:

The Eurasian lynx:

The Eurasian beaver (with babies!):

The white-tailed eagle:

Reindeer in Scotland:

The pine marten:

Show transcript:

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

This week is Caitie Sith and Dave’s episode, where we’ll learn about the re-wilding of Scotland! Re-wilding is the process of restoring an ecosystem to its natural state, basically reversing habitat loss. Most of the time there’s a lot more to it than just reintroducing native animals, but sometimes that’s all that’s required.

Scotland is a part of the island of Great Britain, north of England. People have lived there since the last glaciers melted at the end of the Pleistocene, around 12,000 years ago. During the Pleistocene and a few thousand years after the glaciers melted, Scotland was connected to Europe by a lot of marshy land where today there’s ocean, and naturally many animals lived in Scotland that were also found in Europe at the time. Some of the ice age megafauna that lived in Scotland included the woolly rhinoceros, woolly mammoth, bison, aurochs, wild boar, saiga antelope, giant deer, red deer, reindeer, moose, wild horse, beaver, walrus, Polar bear, brown bear, lynx, wolf, Arctic fox, and cave lion. Many fossil and subfossil remains of Pleistocene animals were destroyed by the formation and movement of thick glacier ice, which scoured the land down to bedrock in many places, so those are only the animals we know for sure lived in Scotland.

But Scotland wasn’t covered by glaciers all the time. The Pleistocene wasn’t a single ice age but a series of cold events interspersed with warming trends. During these interglacial periods, which lasted some 10- to 15,000 years at a time, animals would move to Scotland from other places or become more numerous than before. Then the climate would start cooling again, glaciers would slowly form over many years, and animals would move to areas where there was more food. This happened repeatedly over a period of more than 2.5 million years.

In other words, while we have some fossils of Pleistocene animals that once lived in Scotland, we don’t have nearly as many as have been found in England, Ireland, and Wales. But what we do know is that Scotland was once teeming with all kinds of animals we’d never associate with the country today, like cave lions and Polar bears!

Much of the ice age megafauna went extinct around 12,000 years ago when the last glaciers melted and the climate started warming. Cold-adapted animals couldn’t always survive in a warmer climate, not to mention that as the climate changed, the types of plants available to eat changed too. Some animals migrated away or went extinct, while some were able to stay in Scotland successfully. This included the red deer, reindeer, wild boar, walrus, brown bear, and lynx.

If you’re wondering why that list is full of animals that don’t actually live in Scotland these days, like the brown bear and lynx, it’s because humans hunted many of the native Scottish animals to extinction. Others went extinct due to habitat loss or competition with introduced animals. Many surviving species are endangered today for the same reasons.

For example, the Scottish wildcat, also called the Highland wildcat. We talked about it briefly in episode 52 way back in early 2018. One of the animals that migrated to Scotland after the Pleistocene, but before sea levels rose and cut the British Isles off from Europe, was the European wildcat. The Scottish population has been separated from the European population for at least 7,000 years, and some researchers think it should be classified as a subspecies of European wildcat.

The Scottish wildcat is a little larger than a domestic cat and is always tabby striped. It has a bushy tail with a black tip, a striped face and legs, never any white markings, and is usually dark in color with black paws. It’s a solitary animal that mostly lives in woodlands, where it eats mice, voles, and other rodents, rabbits, and birds. It used to be common throughout much of the British Isles, but these days it’s only found in parts of Scotland.

You’d think people would be excited to have a genuine wildcat living in their country, since wildcats are pretty awesome and eat animals that can damage crops. But for some reason, until recently people thought these wildcats were pests and would shoot them on sight. Some people thought the wildcats were killing game birds, which is rare, or that they were dangerous, which isn’t true. At the same time, the people shooting wildcats were letting their domestic cats roam freely, which has caused an even bigger problem to wildcats than getting shot at.

Like other wildcat species, the Scottish wildcat can and will cross-breed with domestic cats. The resulting kittens are fertile, meaning they can have babies with either wildcats or domestic cats. Kittens are great, of course, but domestic cats are a different species from wildcats. Hybrid cats are less suited to live in the wild, but too wild to be good pets, and if too many domestic cats breed with wildcats, soon there won’t be any real wildcats left. Not only that, domestic cats carry diseases that wildcats can catch.

The Scottish wildcat is a protected species these days, with conservation efforts in place to keep the wildcats and their habitat as safe as possible. One important step is to encourage people to get their domestic cats neutered. This is healthier for pet cats anyway and will help keep tomcats from spraying and fighting, and of course it stops them from having kittens with wildcats.

Another felid that once lived in Scotland is the Eurasian lynx. It still lives in parts of Asia and Europe, but it went extinct in Scotland several hundred years ago, mainly due to deforestation and hunting for its fur. It’s about 28 inches tall at the shoulder, or 70 cm, and is a heavily built animal with thick spotted fur and a short bobtail. The tip of its tail is black although the rest of the animal is mostly tan or brown with darker brown spots, and it has long black tufts of fur on the tips of its ears. It’s slightly bigger than the related Canadian lynx.

Conservationists have wanted to reintroduce the Eurasian lynx to Scotland for years. Since the lynx is threatened in the rest of its range by habitat loss and hunting, reintroducing it to its former range in Scotland would help it and the ecosystem in general. With no large predators to keep their numbers in check, the population of roe deer in Scotland is too high to be healthy, and the lynx loves to eat roe deer.

Some people worry that if the lynx is reintroduced to Scotland, it will be dangerous to humans and livestock. But the lynx is a shy, solitary animal that avoids humans as much as possible. There are enough roe deer alone to sustain a population of over 400 lynxes in the wilder parts of Scotland, especially in the Highlands. The lynx also spends almost all of its time in forests and doesn’t like open pastures. It’s been successfully reintroduced to its former range in other countries, with a nice side effect being increased tourism to national parks where it’s now found.

Scotland also used to have beavers, which were hunted to extinction in the 16th or 17th century. Then, in 2009, the Eurasian beaver was reintroduced to parts of Scotland and is doing great! There are more than 1,000 beavers living in Scotland now. Beavers are considered a keystone species, a term we haven’t really examined on the podcast before, but it means that an animal is so important to an ecosystem that if it goes extinct in an area, the ecosystem sort of falls apart and many other animals go locally extinct soon after.

Beaver ponds create a winter habitat for many types of fish, and beaver dams don’t stop fish like salmon that migrate upriver to spawn. The dams help reduce flooding, improve water quality, and create cover for lots of fish and other animals.

Naturally, though, some people complain about the beavers, because there will always be someone who complains about anything. Some people think beavers eat fish and will eat up all the fish that humans want to catch. Beavers actually don’t eat fish at all, they only eat plant material. Some people think beavers carry the giardia parasite, which causes a bacterial infection sometimes called beaver fever that’s spread in water, but giardia is actually mostly spread by domestic dogs. Some people complain that beavers fell trees and build ponds, and both these things are true. But the beaver is just doing what it’s supposed to do, and as we just learned, this tree felling and pond-making are good for the environment—unlike humans, who chop down lots of trees and make artificial ponds when landscaping, while simultaneously draining wetlands, which doesn’t help the local environment at all. Besides, the beavers are cute and attract tourists who want to get pictures of them, which is also good for the local economy. Everybody wins when there are beavers around, is what I’m trying to say.

The beavers reintroduced in 2009 aren’t the only beavers in Scotland. In 2001, people started seeing them around the river Tay—but no one knew where they came from. Well, presumably someone knew, because the beavers didn’t get there without help. If this reminds you of episode 48, where we talked about some mystery beavers that appeared in Devon, England, the Devon beavers showed up in 2013, twelve years after the Scottish mystery beavers. At first the Scottish government planned to capture the Tayside beavers and keep them in captivity, but the beavers are still there and doing very well.

It’s great that over a thousand beavers live in Scotland now, but that’s actually not very many. Still, it’s a whole lot better than the number of Eurasian beavers about 150 years ago, when researchers think there may have been as few as 300 individuals alive in the whole world.

Another animal that once lived in Scotland, was hunted to extinction, and then mysteriously reappeared recently is the wild boar. They first appeared in the 1990s and by now there are thousands of them in Scotland. It’s possible they escaped from farms, where they’re sometimes raised for meat like domestic pigs. While they’re a native species, they don’t have any predators in Scotland and are causing a lot of damage as they become more numerous. The wild boar’s natural predator is the wolf, and the last wolf in Scotland was killed in 1743. Lynxes will also kill wild boar piglets.

Some birds have been reintroduced to Scotland too. The white-tailed eagle is a type of sea eagle, closely related to the bald eagle of North America although it’s slightly larger than the bald eagle. The biggest ever reliably measured was a specimen from Greenland with a wingspan of 8 feet 4 inches across, or 2.53 meters, just a smidge larger than the largest bald eagle wingspan known. It’s mostly brown and gray with a yellow bill and feet, and a white tail. It lives around water and eats a lot of fish, but it also eats lots of carrion, gulls and other birds, and occasionally small mammals like rabbits. It always lives near water but it prefers wooded areas, especially lowlands and forested islands.

The white-tailed eagle went extinct throughout Britain in the early 20th century when people decided they wanted all those fish the eagle eats for themselves. Never mind that even a thousand eagles couldn’t eat as many fish that a single commercial fishing boat catches in a day. People also decided that eagles killed lambs, even though this is extremely rare. White-tailed eagles would much rather eat fish and seagulls than lamb. The last white-tailed eagles in Scotland were shot and killed in 1916.

As if that wasn’t bad enough, white-tailed eagles were also killed throughout the rest of their range and were especially vulnerable to the chemical called DDT. DDT was a popular pesticide developed in the 1950s and used to kill insects on crops and gardens. But DDT is dangerous, because like other pesticides it doesn’t just do its job and evaporate. It stays in the environment and ends up in the bodies of animals, including people. It’s especially bad for birds that eat a lot of fish, since a lot of pesticides end up in the water, and it causes their eggshells to become so thin and weak that the eggs break when the mother tries to keep them warm. This is the same thing that almost drove the bald eagle to extinction in North America. By the time DDT use was banned in many countries and the white-tailed eagle was declared a protected species, it was almost too late.

Conservation efforts have helped stop the white-tailed eagle from going extinct and its numbers are slowly growing. Starting in 1975, young eagles were brought from Norway to Scotland, where they were successfully reintroduced in the inner Hebrides islands and have now expanded to other parts of Scotland. Some people still complain about the eagles and sometimes shoot or poison them even though it’s illegal, but most people are happy to have them around, especially birdwatchers.

Scotland even has some reindeer these days. Reindeer probably lived in Scotland until around the 12th century, and in 1952 a Swiss herdsman thought they should still be there. He brought a small herd to the Cairngorm mountains, which is now a national park. The reindeer are semi-domesticated but roam free, and they attract tourists who hope to catch a glimpse of them.

At the same time that many native animals have gone extinct, lots of non-native animals have been introduced to Scotland, including wallabies, American mink, gray squirrels, various species of crayfish, and many more. Conservationists are working to minimize the damage these introduced species cause. Many invasive species were animals kept as pets that either escaped or were released into the wild. We talked about the invasive eastern gray squirrel versus the native red squirrel in episode 241, for instance. People released gray squirrels into parks in England because they were so cute, and a hundred years later, the gray squirrels are taking over in many places. They’re increasingly common in Scotland, although Scotland has a small predator called the pine marten that loves to eat squirrels.

The pine marten is a type of mustelid, or weasel relative, that’s common throughout much of Europe and Asia. It grows about two and a half feet long, or 75 cm, including its bushy tail. It mostly lives in wooded areas and spends a lot of its time in trees, hunting squirrels and other small animals like frogs, insects, and birds. It will also eat carrion, bird eggs, and sometimes fruit. It’s mostly brown with a cream-colored throat. It even has partially retractable claws like a cat to help it climb trees, although it’s not related to the cat.

The pine marten is especially good at catching squirrels, and it tends to target the gray squirrel because it’s easier to catch. The red squirrel is more cautious. Where there are pine martens, there are fewer or no gray squirrels. The problem is, the pine marten is considered a pest that kills game birds, so some people shoot or poison it even though it’s a protected species. Then those same people complain about all the gray squirrels around. The pine marten is doing well in many parts of Scotland, though, and has even expanded its range slightly in the last few years.

Scotland is a beautiful country known for its wild and rugged countryside. It wouldn’t take much to rewild it properly, a process that’s well underway with keystone species like beavers already re-established in many places. The main problem is people who don’t understand that a healthy ecosystem requires predators. Without lynxes, wolves, bears, and other large predators, animals like roe deer and wild boar become so numerous that they can’t find enough to eat and either starve or destroy crops and gardens.

Fortunately, many more people in Scotland do understand the importance of building healthy ecosystems. After all, they’re naturally proud of where they live and want to make it even better.

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!