Category Archives: reptile

Episode 385: More Monitors

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Thanks to Cosmo and Zachary for suggesting this week’s monitor lizards!

Further reading:

No One Imagined Giant Lizard Nests Would Be This Weird

The Mighty Modifications of the Yellow-Spotted Goanna

The Asian water monitor:

A yellow-spotted goanna standing up [picture by Geowombats – https://www.flickr.com/photos/geowombats/136601260/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=2595566]:

Show transcript:

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

Last week we had our big dragons episode where we learned about the Komodo dragon and some of its relations, including goannas. I forgot to thank Cosmo for suggesting the lace monitor, also called the tree goanna, in that episode, and I also forgot that Zachary had also suggested monitor lizards as a topic, so let’s learn about two more monitor lizards this week.

Cosmo is particularly interested in aquatic and semi-aquatic animals, and a lot of monitor lizards are semi-aquatic. Let’s learn about the Asian water monitor first, since it’s the second-largest lizard alive today, only smaller than the Komodo dragon.

The Asian water monitor is common in many parts of South and Southeast Asia, including India, Vietnam, Cambodia, Laos, southern China, and many islands. A half dozen subspecies are currently recognized, although there may be more.

The largest water monitor ever reliably measured was 10 1/2 feet long, or 3.2 meters. It’s dark brown or black with yellow speckles and streaks, and young lizards have larger yellow spots and stripes. It lives wherever it can find fresh or brackish water, from lakes and rivers to swamps, ponds, and even sewers.

Like the crocodile, the Asian water monitor’s tail is flattened from side to side, called lateral compression, and it’s also very strong. It swims by tucking its legs against its sides and propelling itself through the water with its tail. It can dive deeply to find food, and while it prefers fresh water, it will swim in the ocean too. That’s why it’s found on so many islands.

Juvenile Asian water monitors spend most of the time in trees, but even a fully grown lizard will sometimes climb a tree to escape danger. Only saltwater crocodiles and humans kill the adults.

In some parts of its range, the water monitor is killed by humans for its meat and its skin, which is used as leather. In other parts of its range, it’s never bothered since it eats venomous snakes and animals that damage crops. It’s sometimes kept as a pet, although it can grow so big that many people who buy a baby water monitor eventually run out of room to keep it. That’s how so many have ended up in the waterways of Florida and other areas far outside of its natural range, from people letting pets go in the wild even though doing so is illegal and immoral.

While most of the time the water monitor isn’t dangerous to humans, if it feels threatened, it can be quite dangerous. Like the Komodo dragon and other monitor lizards, it’s venomous, plus its teeth are serrated, its jaws are strong, and it has sharp claws. It eats a lot of carrion, along with anything it can catch. A population in Java even enters caves to hunt bats that fall from the ceiling.

Zachary didn’t suggest a particular type of monitor lizard, so let’s learn about the yellow-spotted goanna. Goannas are a type of monitor lizard found in Australia, New Guinea, and some nearby areas. We talked about some of them last week, including Cosmos’s suggestion of the lace monitor, but after the episode was released I found an article I had saved over a year ago. It’s about the yellow-spotted goanna, and a remarkable discovery about how it takes care of its eggs.

The yellow-spotted goanna lives in parts of Australia and southern New Guinea, and a big male can grow up to five feet long, or 1.5 meters. It can swim and climb trees when it wants to, but mainly it stays on the ground, although it prefers to live near water if possible. It’s a fast runner and chases its prey instead of ambushing it. It eats small animals like rodents, birds, fish, insects, and reptiles, including other monitor lizards.

If you remember last week’s episode, the female tree goanna digs a hole into a termite nest to lay her eggs inside. The termites repair the hole in their nest, which means the eggs are nicely hidden from predators and protected from weather, and when the babies hatch they have lots of termites to eat. That’s weird enough, but the yellow-spotted goanna female has an even more interesting way of protecting her eggs.

The yellow-spotted goanna digs a big burrow to hide in, and it spends a lot of its time in the burrow when it’s not out hunting. Researchers assumed the female laid her eggs in the burrow, but every time they investigated a female’s burrow, it was empty.

In 2012, a herpetologist named Sam Doody hoped to figure out where the female hid her eggs. He thought the eggs might be buried inside the burrow. When a female left her burrow, he and his team examined the burrow carefully. Doody noticed that the dirt at the end of the burrow felt softer than the walls, and he dug into it carefully, convinced he would find the eggs right away.

Instead, he and his team kept digging, following the softer dirt. It took them hours and hours, since they had to be really careful, and the filled-in burrow just kept going. It descended five feet, or 1.5 meters, into the ground in a corkscrew shape, more properly called helical, and at the very bottom the team found a nest of ten eggs.

Since then, Doody and his colleagues have studied many other yellow-spotted goanna nests and they’re all helical in shape and as much as 13 feet deep, or 4 meters. The extreme depth is related to how long it takes the eggs to hatch, about 8 months. If the eggs were closer to the surface, they would get too hot and dry to hatch. There’s more moisture and a constant temperature deep underground.

It takes the female more than a week to dig her tunnel and the small nesting chamber at the bottom. She lays her eggs, then returns to the surface, letting the sandy soil collapse behind her to hide and protect the eggs. The females also frequently nest together, sometimes sharing a nesting chamber. Doody’s team once found a nesting chamber as big as a room of your home but only about as tall as a mattress, with more than 100 clutches of eggs laid in it. The females often re-use the same burrows year after year. When the eggs hatch, the baby lizards dig their way out of the nesting chamber–but they dig straight up instead of using the softer parts of the helical structure.

Other animals move into the loose soil of the nesting burrows, especially frogs. When excavating one burrow, Doody’s team found 418 frogs, along with numerous small reptiles, invertebrates, and even mammals, all of them spending the dry season comfortably inside the loose soil in the spiral burrow. I wonder if the mother lizard sometimes digs some of these frogs out to eat as a snack. Watch out, frogs!

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

Thanks for listening!

Episode 384: Dragons Revisited

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This week we need to thanks a bunch of listeners for their suggestions: Bowie, Eilee, Pranav, and Yuzu!

Further reading:

Elaborate Komodo dragon armor defends against other dragons

Giant killer lizard fossil shines new light on early Australians

A New Origin for Dragon Folklore?

The Wyvern of Wonderland

The Komodo dragon:

The beautiful tree goanna:

The perentie:

Fossilized scale tree bark looks like reptile scales:

Show transcript:

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

This week we’re going to revisit a popular topic we talked about back in episode 53. That episode was about dragons, including the Komodo dragon. Since then, Bowie has requested to learn more about the Komodo dragon and Eilee and Pranav both suggested an updated dragon episode. We also have a related suggestion from Yuzu, who wants to learn more about goannas in general.

We’ll start with the Komodo dragon, which gets its name because it’s a huge and terrifying monitor lizard. It can grow over 10 feet long, or 3 meters, which means it’s the biggest lizard alive today. It has serrated teeth that can be an inch long, or 2.5 cm, and its skin is covered with bony osteoderms that make it spiky and act as armor. Since the Komodo dragon is the apex predator in its habitat, it only needs armor to protect it from other Komodo dragons.

Fortunately for people who like to hike and have picnics in nature, the Komodo dragon only lives on four small islands in Indonesia in southeast Asia, including the island of Komodo. Young Komodo dragons have no armor and spend most of the time in trees, where they eat insects and other small animals. As the dragon gets older and heavier, it spends more and more time on the ground. Its armor develops at that point and is especially strong on the head. The only patches on the head that don’t have osteoderms are around the eyes and nostrils, the edges of the mouth, and over the pineal eye. That’s an organ on the top of the head that can sense light. Yes, it’s technically a third eye!

The Komodo dragon is an ambush predator. When an animal happens by, the dragon jumps at it and gives it a big bite from its serrated teeth. Not only are its teeth huge and dangerous, its saliva contains venom. It’s very good at killing even a large animal like a wild pig quickly, but if the animal gets away it often dies from venom, infection, and blood loss.

Like a lot of reptiles, the Komodo dragon can swallow food that’s a lot bigger than its mouth. The bones of its jaws are what’s called loosely articulated, meaning the joints can flex to allow the dragon to swallow a goat whole, for instance. Its stomach can also expand to hold a really big meal all at once. After a dragon has swallowed as much as it can hold, it lies around in the sun to digest its food. After its food is digested, which can take days, it horks up a big wad of whatever it can’t digest. This includes hair or feathers, horns, hooves, teeth, and so on, all glued together with mucus.

A Komodo dragon eats anything it can catch, and the bigger the dragon is, the bigger the animals it can catch. One thing Komodo dragons are just fine with eating are other Komodo dragons.

As we mentioned a few minutes ago, the Komodo dragon is a type of monitor lizard, and there are lots of monitor lizards that live throughout much of the warmest parts of the earth, including Australia. Yuzu suggested we talk about the goanna, which is the term for monitor lizards in the genus Varanus, although it’s also a term sometimes used for all monitor lizards. Goannas are more closely related to snakes than to other types of lizard.

Like the Komodo dragon, the goanna will eat pretty much any animal it can catch, and will also scavenge already dead animals. Smaller goannas mostly eat insects, especially the tiny goanna often called the short-tailed pygmy monitor or just the pygmy monitor. Its tail is actually pretty long for its size. It only grows about 8 inches long at most, or 20 cm, and babies are less than the length of your pinkie finger. It spends most of its time underground in a burrow, but comes out to hunt for grasshoppers and other insects, spiders, scorpions, and sometimes frogs and small snakes. Many species of goanna spend the hottest part of the day in a burrow, and some species will hibernate in winter.

Most goannas spend all their time on the ground unless they’re actually underground, but some live in trees. The tree goanna, also called the lace monitor or just lacy, can grow up to seven feet long, or over two meters, but is lightly built to climb around on tree branches looking for food. The tree goanna eats a whole lot of bird eggs, along with whatever animals it can catch in trees or on the ground. It eats a lot of carrion and will even get into trash cans if it smells food. When the female is ready to lay her eggs, she digs a hole in the side of a termite nest and lays them in the nest. The termites repair the hole, which hides the eggs, and when the babies hatch, they have lots of termites to eat. The mother goanna keeps watch on the termite nest and once her eggs hatch, she’ll dig into it again to let her babies out.

Genetic testing has discovered that the tree goanna is the closest living relative to the Komodo dragon, but another relative is the biggest goanna alive today in Australia. It’s called the perentie and it can definitely grow up to 8 and a half feet long, or 2.5 meters, and possibly close to 10 feet long, or 3 meters. That’s almost the length of the Komodo dragon.

Long as it is, the perentie isn’t very heavy for its size. It has big claws that allow it to dig quickly, so that if it feels threatened it can dig a burrow and hide in it in only a few minutes. It can also climb trees and is a fast runner. Sometimes it will rear up on its hind legs, propping itself up with its tail, to get a good look around. It’s covered with a maze-like pattern of spots and speckles, and it has a very long neck and a very long tail. Like most monitor lizards, its head is flattened so that it looks a little like a snake’s head. Also like other monitor lizards, it has a long forked tongue that it flicks in and out like a snake to detect the chemical signature of other animals nearby, sort of like smelling but with the tongue.

Also like other monitor lizards, the perentie has a venomous bite. Its venom isn’t all that strong, but you still wouldn’t want to get nipped by one. A big perentie will kill and eat just about anything it can catch, including wombats and small kangaroos. It’s not dangerous to humans, though, and in fact very few people in Australia have ever seen a perentie in the wild. It’s shy and lives in remote areas, mostly in the interior of the country over to the western coast.

There used to be a goanna in Australia that was even bigger than the perentie, but it went extinct around 50,000 years ago. We talked about it briefly in episode 325, but Pranav suggested we learn more about it. It’s called megalania and not only was it bigger than the perentie, it made the Komodo dragon look like a little baby lizard. Megalania may have grown as much as 23 feet long, or 7 meters, although most scientists these days think it wasn’t quite that big. The latest estimates are still pretty big, possibly 18 feet long, or 5.5 meters. It was also heavily built, more like the Komodo dragon than the perentie, so it may have weighed as much as a polar bear. That’s about 1200 pounds, or around 550 kg, but I thought the polar bear comparison was funny. We don’t know for sure how big megalania was because we don’t have a complete skeleton.

Megalania has been classified with the living goannas in the genus Varanus, so it was probably related to the Komodo dragon, although we don’t know exactly how closely. It was probably venomous, and we know its teeth were serrated like the Komodo dragon’s. It lived throughout much of eastern Australia and may have been even more widespread, we just don’t know because we don’t have very many fossils.

Megalania lived alongside another giant monitor lizard in what is now Queensland, the Komodo dragon. That’s right, the Komodo dragon once lived in Australia, although it went extinct there around 300,000 years ago. Megalania went extinct around the time that humans first arrived in Australia, so it’s very possible that the ancestors of today’s Aboriginal Australians encountered it. In 2015, a study was published detailing the discovery of a large goanna osteoderm from a cave system in Queensland. The osteoderm has been dated to about 50,000 years ago and probably belonged to megalania, and some scientists think humans may have been a factor in its extinction, along with climate change.

There are supposedly stories passed down for thousands of years among the Aboriginal Australian peoples that suggest meetings with megalania. I tried hard to find accounts of any of these stories to share, but the sources were always questionable. I did learn that European accounts of the Dreamtime, especially older ones, are inaccurate at best. European colonizers didn’t fully understand the Aboriginal cultures and in many cases weren’t interested in understanding them. They just wanted to collect stories that they would then change to fit the European worldview. This trend continues to the present day, with non-Aboriginal writers changing, misinterpreting, or even straight up inventing Dreamtime stories to fit their own interests. Sometimes that interest is cryptozoology. From what I was able to discover, there really is one aspect of the Dreaming that does apparently include a giant goanna, but that the traditions involved are especially sacred and not meant for outsiders to learn. So it’s none of our business.

As we discussed in episode 53, European stories about dragons were probably inspired by snakes, since early dragons were described as snake-like. Dragon stories in other parts of the world were probably inspired by various local reptiles such as crocodiles. Fossilized bones also played a part, since in the olden days no one knew what dinosaurs were. All anyone knew was that sometimes they found gigantic bones that seemed to be made of stone, and people made up stories to explain them.

Stories about giant reptiles are common throughout much of the world, and in 2020 a study was published suggesting that one of the reasons wasn’t an animal at all. It was a plant, specifically a 300 million year old plant called Lepidodendron, also called the scale tree.

The scale tree wasn’t actually a tree, but it was a really big plant that could grow 160 feet tall, or 50 meters. It’s been extinct for a long time, but it does have living relations called quillworts that kind of look like weird grass.

The scale tree gets its name from the diamond-shaped pattern on its trunk, which looks for all the world like reptile scales. These were just places where leaves once grew, but as the plant got taller, it shed its lower leaves as new ones grew from the top. Different species of the plant had different scale patterns. The study suggests that fossilized pieces of scale tree trunks inspired stories about giant reptiles. Since the plants grew throughout the supercontinent Pangaea and often ended up fossilized in coal beds, their fossils have been found in many different parts of the world.

Let’s finish with a dragon story from England, specifically the village of Sockburn in County Durham. It’s referred to as the Sockburn Worm, since “worm” used to mean any creature that was snakey or worm-shaped in appearance. It’s closely related to the story of the Lambton Worm that we talked about in episode 53.

Once upon a time in the olden days, maybe around 750 years ago, maybe longer ago, Sockburn and the farmland around it were terrorized by a dragon. The dragon had a poisonous breath and would eat anyone it came across, and killed and ate all the livestock it could find. No one could kill it.

Sir John Conyers was a knight who lived in the area and he decided he had to do something. He got dressed in his armor and went to the local church to pray, and said he would give up his only son’s life if it meant killing the dragon. Then he set out to find the dragon.

He didn’t so much find the dragon as the dragon found him. Instead of getting eaten, Sir John drew his magical sword and battled the dragon until finally he lopped its head off with one massive chop. Sir John survived and so did his son.

Centuries later, in 1855, a writer was inspired by the story and wrote a poem based on it. He eventually included the poem in a book called Alice Through the Looking-Glass, the sequel to Alice in Wonderland. You may know the poem “The Jabberwock,” and now you know the dragon story that inspired it.

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

Thanks for listening!

Episode 378: Ichthyotitan

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Thanks to Nathan-Andrew for suggesting giant ichthyosaurs!

Further reading:

Paleontologists unearth what may be the largest known marine reptile

Ruby and some other scientists with the ichthyotitan fossils [photos taken from this page]:

How the pieces fit together:

Show transcript:

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

This week we’re going to learn about some of the biggest animals that have ever swum through the oceans of this planet we call Earth, a suggestion from Nathan-Andrew.

We talked about ichthyosaurs way back in episode 63, but we haven’t really discussed these giant marine reptiles since. Ichthyosaurs and their close relations were incredibly successful, first appearing in the fossil record around 250 million years ago and last appearing around 90 million years ago. Most ichthyosaurs grew around 6 and a half to 11 feet long, or 2 to 3.3 meters, depending on species, so while they were pretty big animals, most of them weren’t enormous. They would have been fast, though, and looked a lot like fish or dolphins.

Even though ichthyosaurs were reptiles, they were warm-blooded, meaning they could regulate their body temperature internally without relying on outside sources of heat. They breathed air and gave birth to live babies the way dolphins and their relations do. They had front flippers and rear flippers along with a tail that resembled a shark’s except that the lower lobe was larger than the upper lobe. Some species had a dorsal fin too. They had huge eyes, which researchers think indicated they dived for prey. Not only were their eyes huge, they were protected by a bony eye ring that would help the eyes retain their shape even under deep-sea pressures.

We know a lot about what ichthyosaurs ate, both from coprolites, or fossilized poops, and from the fossilized remains of partially digested food preserved in the stomach area. Most ichthyosaurs ate cephalopods like squid and ammonites, along with fish, turtles, and pretty much any other animals they could catch. Ichthyosaurs also ate smaller ichthyosaurs.

Nathan-Andrew specifically suggested we look at Shastasaurus and Shonisaurus, two closely related genera that belong to the ichthyosaur family Shastasauridae. Both genera contained species that were much larger than the average dolphin-sized ichthyosaur. The biggest species known until recently was Shonisaurus sikanniensis, which grew to almost 70 feet long, or 21 meters.

Scientists are divided as to whether S. sikanniensis should be considered a species of Shonisaurus or if it should be placed in the genus Shastasaurus. The main difference is that species in the genus Shastasaurus were more slender and had a longer, pointier rostrum than species in the genus Shonisaurus. Either way, S. sikanniensis was described in 2004 and at the time was the largest ichthyosaur species ever discovered.

But in May of 2016 a fossil enthusiast came across five pieces of what he suspected was an ichthyosaur bone along the coast of Somerset, England. He sent pictures to a couple of marine reptile experts, who verified that it was indeed part of an ichthyosaur’s lower jawbone, called a surangular. Studies of the fossil pieces compared it to S. sikanniensis, and it was similar enough that the new fossil was tentatively placed in the family Shastasauridae. Based on those comparisons, scientists estimated that this new ichthyosaur might have grown to around 72 feet long, or 22 meters, or even longer.

Almost exactly four years after the 2016 discovery, in May of 2020, an 11-year-old named Ruby Reynolds was looking for fossils with her father on the beach at Somerset. She discovered two big chunks of a fossil bone that she thought might be important. Ruby’s father contacted a local paleontologist, who in turn reached out to the man who had found and helped study the 2016 surangular bone. They studied the 2020 fossil and determined that it too was a surangular bone, and looked a lot like the one found in 2016. Not only was it better preserved and more complete, it was bigger.

Ruby and her father joined the team of paleontologists searching for more pieces of the surangular, and they actually found them. The pieces fit together like jigsaw puzzle pieces.

The bone has been dated as being about 202 million years old, from right before the end-Triassic extinction event and 13 million years after the other most recent ichthyosaur fossils from this era. It was described in early 2024 and named Ichthyotitan, and I’m happy to report that Ruby and her father helped with the research and are both included in the list of authors in the paper describing it. They also helped name it.

The estimated size of this specific Ichthyotitan specimen is about 25 meters, or 82 feet. That’s incredibly huge, rivaling the biggest whales alive today. But one other detail about this ichthyotitan bone is even more stunning. When the animal died, it was still growing. It hadn’t reached its full size yet.

As a comparison, the biggest animal ever known to have lived is the blue whale. A blue whale can grow up to 98 feet long, or 30 meters. Until now, scientists thought that no other animal had ever reached the size of a blue whale. Now, some paleontologists suspect that a full-grown ichthyotitan might have been at least as long or even longer than a blue whale.

The next step, of course, is to find more of the fossils. Ichthyotitan’s only fossils so far have been found in Somerset, England, but fossils of closely related ichthyosaurs have been found in parts of California, Nevada, British Columbia, China, Italy, Switzerland, and Tibet. In other words, they might be found just about anywhere with rocks dating to about 200 million years ago. The next time you’re out for a walk, keep a look-out just in case you spot a bone belonging to the biggest animal that ever lived.

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

Thanks for listening!

Episode 377: The Giant-est Snake Ever

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Thanks to Max for suggesting Titanoboa!

Further reading:

Largest known madtsoiid snake from warm Eocene period of India suggests intercontinental Gondwana dispersal

This Nearly 50-Foot Snake Was One of the Largest to Slither on Earth

Meet Vasuki indicus, the ‘crocodile’ that was a 50ft snake

Titanoboa had really big bones compared to its modern relatives:

Vasuki had big bones too:

Show transcript:

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

Almost exactly two years ago now, Max emailed to suggest we talk about titanoboa. The problem was that we had covered titanoboa in episode 197, and even though there’s always something new to learn about an animal, in this case since titanoboa is extinct there wasn’t much more I could share until new studies were published about it. But as the years passed I felt worse and worse that Max was waiting so long. A lot of listeners have to wait a long time for their suggested episode, and I always feel bad. But still there were no new studies about titanoboa!

Why am I telling you all this? Because we’re finally going to talk about titanoboa today, even though by now Max is probably old and gray with great-grandkids. But we’re only going to talk about titanoboa to compare it to another extinct snake. That’s right. Paleontologists have discovered fossils of a snake that was even longer than titanoboa!

Let’s start with Titanoboa, because it’s now been a really long time since episode 197 and all I remember about it is that it’s extinct and was way bigger than any snake alive today. Its discovery is such a good story that I’m going to include it too.

In 1994, a geologist named Henry Garcia found an unusual-looking fossil in Colombia in South America, in an area that had been strip-mined for coal. Fifty-eight million years ago the region was a hot, swampy, tropical forest along the edge of a shallow sea.

Garcia thought he’d found a piece of fossilized tree. The coal company in charge of the mine displayed it in their office along with other fossils. There it sat until 2003, when palaeontologists arranged an expedition to the mine to look for fossil plants. A researcher named Scott Wing was invited to join the team, and while he was there he poked around among the fossils displayed by the mining company. The second he saw the so-called petrified branch he knew it wasn’t a plant. He sent photos to a colleague who said it looked like the jawbone of a land animal, probably something new to science.

In 2007, the fossil was sent for study, labeled as a crocodile bone. But the palaeontologists who examined the fossil in person immediately realized it wasn’t from a crocodile. It was a snake vertebra—but so enormous that they couldn’t believe their eyes. They immediately arranged an expedition to look for more of them, and they found them!

Palaeontologists have found fossilized remains from around 30 individual snakes, including young ones. The adult size is estimated to be 42 feet, or 13 meters. The largest living snakes are anacondas and reticulated pythons, with no verified measurements longer than about 23 feet long, or 7 meters. Titanoboa was probably twice that length.

Because titanoboa was so bulky and heavy, it would be more comfortable in the water where it could stay cool and have its weight supported. It lived in an area where the land was swampy with lots of huge rivers. Those rivers were full of gigantic fish and other animals, including a type of lungfish that grew nearly ten feet long, or 3 meters. Studies of titanoboa’s skull and teeth indicate that it probably mostly ate fish.

So if titanoboa was so huge that until literally a few days ago as this episode goes live, we thought it was the biggest snake that had ever existed, how big was this newly discovered snake? It’s called Vasuki indicus and while it wasn’t that much bigger than titanoboa, estimates so far suggest it could grow almost 50 feet long, or over 15 meters. It’s named after a giant serpent king called Vasuki from Hindu folklore, who symbolizes strength and prosperity.

Vasuki indicus was discovered in a mine in India in 2005. The original discovery consisted of 27 vertebrae, including some that were still articulated. That means they remained in place after the rest of the body decayed and were preserved that way, which helps palaeontologists better estimate the snake’s true size.

Like titanoboa, the fossils were misidentified at first. They were labeled as a known giant crocodile and set aside in the discoverer’s lab for decades. In 2022, paleontologist Debajit Datta joined the lab, and one of the things he wanted to study were these giant crocodile fossils. He started preparing them for study by removing the rock matrix from around them, and almost immediately realized they belonged to a snake, not a crocodile.

The fossils have been dated to about 47 million years ago in what is now India, in Asia. Titanoboa lived about 58 million years ago in what is now Colombia, in South America. The two snakes are related, although not closely, and this helps scientists determine how snakes spread across the world as the continents moved into their current positions.

Both snakes lived in what were then very similar habitats, a tropical, swampy area near the coast. The researchers think Vasuki spent most of its time on land, unlike titanoboa. It wasn’t as bulky as titanoboa and could probably maneuver on land a lot more easily.

Until titanoboa was described in 2009, a snake called Gigantophis was thought to be the largest snake that ever lived. It lived around 40 million years ago in what is now the northern Sahara desert and could grow over 35 feet long, or almost 11 meters. It turns out that Vasuki was closely related to gigantophis.

As it stands now, until more fossils are found and more studies are conducted and published, Vasuki is estimated to be slightly longer than titanoboa at maximum, making it the longest snake known, but titanoboa is still estimated to be the heaviest snake known. So they both win the largest snake award, but the real winner is us.

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

Thanks for listening!

Episode 376: The Horned Lizard AKA Horny Toad

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Thanks to Khalil for suggesting the horny toad, also called the horned lizard or horned toad!

Further reading:

The Case of the Lost Lizard

The Texas horned lizard:

Texas Horned Lizard (Phrynosoma cornutum)

The rock horned lizard [photo taken from article linked above]:

Show transcript:

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

This week we’re going to learn about a reptile suggested by Khalil, who is Leo’s friend, so a big shout-out to both. Khalil wants to learn about the horny toad, also called the horned toad or horned lizard.

We talked about it briefly back in episode 299. The horny toad is actually a lizard that lives in various parts of North America, especially western North America, from Canada down through much of the United States and into Mexico. The largest species is the Texas horned lizard, with a big female growing about 5 inches long, or almost 13 cm, not counting its tail.

The horny toad does actually resemble a toad in some ways. Its body is broad and rounded and its face has a blunt, froglike snout. Its tail is quite short. It’s also kind of sluggish and spends a lot of time just sitting in the sun, relying on its mottled coloration to camouflage it. If it feels threatened, it will actually just freeze and hope the predator doesn’t notice it. It’s covered with little pointy scales, and if a predator does approach, it will puff up its body so that the scales stick out even more and it looks larger. It also has true horns on its head, little spikes that are formed by projections of its skull, and if a predator tries to bite it, the horny toad will jerk its head up to stab its horns into the predator’s mouth.

Horny toads mainly eat a type of red ant called the harvester ant. The harvester ant is venomous but the horny toad is resistant to the venom and is specialized to eat lots and lots of the ants. Its esophagus produces lots of mucus when it’s eating, which collects around the ants and stops them from being able to bite before they die.

Because it eats so many venomous ants, many scientists think the horny toad stores some of the toxins in its body, especially in its blood. Its blood tastes especially bad to canids like coyotes that are common in the areas where it lives. But it does the horny toad no good to have bad-tasting blood if a predator has to bite it to find out, so the horny toad has a way to give a predator a sample of its blood in the weirdest way you can imagine.

If a horny toad is cornered by a predator and can’t run away, and puffing up isn’t helping deter the predator, the lizard has one last trick up its sleeve. It increases the blood pressure in its head by restricting some of the blood vessels carrying blood back to the heart, and when the blood pressure increases enough, it causes tiny blood vessels around the eyelids to rupture. It doesn’t just release blood, it squirts blood up to five feet away, or 1.5 meters. As if that wasn’t metal enough, the horny toad can aim this stream of blood, and it aims it right at the predator’s eyes.

Imagine for a moment that you are a hungry coyote. You’re young and don’t know that horny toads taste bad, you just know you’ve found this plump-looking lizard that doesn’t move very fast. It keeps puffing up and looking spiky, but you’re hungry so you keep charging in to try and grab it with your teeth in a way that won’t hurt your tongue on those spikes. Then, suddenly, your eyes are full of lizard blood that stings and makes it hard to see, and the blood drips down into your mouth and it tastes TERRIBLE. It doesn’t matter how hungry you are, this fat little lizard is definitely off the menu. Meanwhile, the horny toad is fine.

Scientists aren’t sure if every species of horny toad can squirt blood. Some species probably can’t, while some do it very seldom. It also doesn’t help against some predators, like birds, who don’t have a great sense of taste and aren’t affected by the toxins in the horny toad’s blood.

The horny toad relies on the harvester ant for most of its specialized diet, although it does eat other insects too. It can’t survive without eating harvester ants. The problem is, the harvester ant is in decline after fire ants were introduced to North America from South America. The horny toad doesn’t eat fire ants, and the fire ants out-compete the local harvester ants, leaving the horny toad with less and less food.

Humans really don’t like fire ants, which can cause damage to homes when they dig their huge underground nests, and which inflict really painful bites. When people try to get rid of fire ants, sometimes the treatments also kill harvester ants. Incidentally, some animals that really love to eat fire ants include armadillos, black widow spiders, wolf spiders, and bobwhites.

The Texas horned lizard lives throughout a fairly large range, so although its numbers are in decline along with its ant food, it’s still doing okay for now. But not every horny toad is so lucky.

The rock horned lizard, also called Ditmars’ horned lizard, is only found in one small part of Sonora in northern Mexico. It was first discovered by science in 1891, when an archaeological expedition caught one. The lizard was described in 1906 but by then it hadn’t actually been seen in the wild since 1897, when two more were caught by a man who donated them to the New York Zoological Park. Those were the only three specimens that had ever been collected. Herpetologists worried that the rock horned lizard had gone extinct.

The main issue was that no one was exactly sure where those three specimens had been collected and no one knew exactly where the 1891 expedition had traveled. The man who caught the two lizards in 1897 didn’t say exactly where he’d caught them, just that it was in northern Sonora. But what a scientist named Vincent Roth realized when researching the lizard is that the three preserved specimens probably still contained undigested and partially digested food in their bodies, and that if the insects the lizards had eaten could be identified, it could give an important clue as to where the lizards had lived.

Dr. Roth requested that the gut contents be removed from the 1891 specimen for study, and also from one of the 1897 specimens. The third specimen had been taxidermied and the guts discarded. Dr. Roth cleaned the gut contents with alcohol and examined them microscopically, and found the remains of 14 insects, the seeds of three different species of grass, and some pebbles. All this happened in 1970, so instead of emailing a bunch of experts for help, Dr. Roth had to write physical letters to specialists throughout the world for help identifying the insects.

The specialists were happy to help, and they determined that the pebbles and grass seeds would have been eaten by accident when the lizard slurped up ants carrying them. The lizards had the remains of several different ants in their digestive tracts, including harvester ants, along with weevils, jumping spiders, grasshoppers, and other insects. These were identified, including some rare ones only ever found in certain areas of Sonora. Even the grass seeds and the pebbles were identified.

It all pointed to a particular mountain range in northern Sonora, and an expedition was arranged by Dr. Roth to search for the lizard. But they didn’t find it! They made plans to return, but asked the local people to keep an eye out for a specific type of horned lizard. In 1971 a report came of a rock horned lizard discovered by a local, followed soon by a few others. The lizard was safe, although it’s rare. Scientists had just been looking in the wrong place for it.

Since the rock horned lizard is only a few inches long and blends in so well with its surroundings, it’s no wonder it was hard to find. Fortunately it’s been rediscovered so that scientists can study it and keep it safe. The next step is to keep the harvester ants safe so that all the horny toads have plenty of yummy ants to eat.

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

Thanks for listening!

Episode 364: Animals Who Will Outlive Us All

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Thanks to Oz from Las Vegas for suggesting this week’s topic!

Further reading:

Bobi, the supposed ‘world’s oldest dog’ at 31, is little more than a shaggy dog story

Greenland sharks live for hundreds of years

Scientists Identify Genetic Drivers of Extreme Longevity in Pacific Ocean Rockfishes

Scientists Sequence Chromosome-Level Genome of Aldabra Giant Tortoise

Giant deep-sea worms may live to be 1,000 years old or more

A Greenland shark [photo by Eric Couture, found at this site]:

The rougheye rockfish is cheerfully colored and also will outlive us all:

An Aldabra tortoise all dressed up for a night on the town:

Escarpia laminata can easily outlive every human. It doesn’t even know what a human is.

Show transcript:

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

This week we have a great suggestion by Oz from Las Vegas. Oz wanted to learn about some animals that will outlive us all, and gave some suggestions of really long-lived animals that we’ll talk about. We had a similar episode several years ago about the longest lived animals,where for some reason we talked a lot about plants, episode 168, but this is a little different.

But first, a quick correction! Last week we talked about the dodo and some of its relations, including the Nicobar pigeon. I said that the Nicobar pigeon lived in the South Pacific, but Pranav caught my mistake. The Nicobar pigeon lives in the Indian Ocean on the Nicobar Islands, which I should have figured out because of the name.

Anyway, back in the olden days when I was on Twitter all the time, I came across a tweet that’s still my absolute favorite. Occasionally I catch myself thinking about it. It’s by someone named Everett Byram who posted it in January 2018. It goes:

“DATE: so tell me something about yourself

“ME: I am older than every dog”

Not only is it funny, it also makes you thoughtful. People live a whole lot longer than dogs. The oldest living dog is a chihuahua named Spike, who is 23 years old right now. A dog who was supposed to be even older, 31 years old, died in October of 2023, but there’s some doubt about that particular dog’s actual age. Pictures of the dog taken in 1999 don’t actually look like the same dog who died in 2023.

The oldest cat who ever lived, or at least whose age is known for sure, died in 2005 at the age of 38 years. The oldest cat known who’s still alive is Flossie, who was born on December 29th, 1995. If your birthday is before that, you’re older than every cat and every dog.

The oldest human whose age we know for sure was Jeanne Calment, who died in 1997 at the age of 122 years. We talked about her in episode 168. The oldest human alive today, as far as we know, is Maria Branyas, who lives in Spain and will turn 117 years old on her next birthday in March 2024.

It’s not uncommon for ordinary people to live well into their 90s and even to age 100, although after you reach the century mark you’re very lucky and people will start asking you what your secret for a long life is. You might as well go ahead and make something up now to tell people, because it seems to mainly be genetics and luck that allow some people to live far beyond the lives of any dog or cat or most other humans. Staying physically active as you age also appears to be an important factor, so keep moving around.

But there are some animals who routinely outlive humans, animals who could post online and say “I am older than every human” and the others of its species would laugh and say, “Oh my gosh, it’s true! I’m older than every human too!” But they don’t have access to the internet because they are, for instance, a Greenland shark.

We talked about the Greenland shark in episode 163. It lives in the North Atlantic and Arctic Oceans where the water is barely warmer than the freezing point. It can grow up to 23 feet long, or 7 meters, with females being larger than males. Despite getting to such enormous sizes, it only grows one or two centimeters a year, and that was a clue for scientists to look into how old these sharks can get.

In 2016, a team of scientists published a study about how they determined the age of Greenland sharks that had been accidentally caught by fishing nets or that had otherwise been discovered already dead. The lenses inside vertebrate eyeballs don’t change throughout an animal’s life. They’re referred to as metabolically inactive tissue, which means they don’t grow or change as the animal grows. That means that if you can determine how old the lens is, you know when the animal was born, or hatched in the case of sharks.

In the past, scientists have been able to determine the age of dead whales using their eye lenses, but the Greenland shark was different. It turns out that the shark can live a whole lot longer than any whale studied, so the scientists had to use a type of carbon-14 dating ordinarily used by archaeologists.

The Greenland shark may be the oldest-living vertebrate known. Its life expectancy is at least 272 years, and probably closer to 500 years. Individual sharks can most likely live much longer than that. It’s not even mature enough to have babies until it’s about 16 feet long, or 5 meters, and scientists estimate it takes some 150 years to reach that length. Females may stay pregnant for at least 8 years, and maybe as long as 18 years. Babies hatch inside their mother and remain within her, growing slowly, until they’re ready to be born.

The Greenland shark is so big, so long-lived, and lives in such a remote part of the ocean that taking so long to reproduce isn’t a problem. Its body tissues contain chemical compounds that help keep it buoyant so it doesn’t have to use very much energy to swim, and which have a side effect of being toxic to most other animals. Nothing much wants to eat the Greenland shark. But it is caught by accident by commercial fishing boats, with an estimated 3,500 sharks killed that way every year. Scientists hope that by learning more about the Greenland shark, they can bring more attention to its plight and make sure it’s protected. There’s still a lot we don’t know about it.

At least one species of whale does live much longer than humans. In 2007, researchers studying a dead bowhead whale found a piece of harpoon embedded in its skin. It turned out to be a type of harpoon that was manufactured between 1879 and 1885. After that, scientists started testing other bowhead whales that were found dead. The oldest specimen studied was determined to be 211 years old when it died, and it’s estimated that the bowhead can probably live well past 250 years if no one harpoons it and it stays healthy. It may be the longest-lived mammal. It has a low metabolic rate compared to other whales, which may contribute to its longevity.

Most small fish don’t live very long even if nothing eats them. Rockfish, for instance, only live for about 10 years even if they’re really lucky. Well, most rockfish. There is one species, the rougheye rockfish, that lives much, much longer. Its lifespan is at least 200 years old.

The rougheye rockfish has a lot of other common names. Its scientific name is Sebastes aleutianus. It can grow over 3 feet long, or 97 cm, and is red or orangey-red. It lives in cold waters of the Pacific, where it usually stays near the sea floor. It eats other fish along with crustaceans.

Naturally, scientists are curious as to why the rougheye rockfish lives so long but its close relations don’t. In 2021 a team of scientists published results of a genetic study of the rougheye rockfish and 87 other species. They discovered a number of genes associated with longevity, along with genes controlling inflammation that may help the fish stay healthy for longer.

The rougheye rockfish only evolved as a separate species of rockfish about ten million years ago. Because the longest-living females lay the most eggs, the genes for longevity are more likely to be passed on to the next generation, which means that as time goes on, lifespans of the fish overall get longer and longer. The rougheye also isn’t the only species of rockfish that lives a long time, it’s just the one that lives longest. At least one other species can live over 150 years and quite a few live past 100 years.

Another animal that can easily outlive humans is the giant tortoise, which we talked about in episode 95. Giant tortoises are famous for their longevity, routinely living beyond age 100 and sometimes more than 200 years old. The oldest known tortoise is an Aldabra giant tortoise that may have been 255 years old when it died in 2006. The Aldabra giant tortoise is from the Aldabra Atoll in the Seychelles, a collection of 115 islands off the coast of East Africa.

Scientists studied the Aldabran tortoise’s genetic profile in 2018 and learned that in addition to genes controlling longevity, it also has genes that control DNA repair and other processes that keep it healthy for a long time.

Oz also suggested the infinite jellyfish, also called the immortal jellyfish. An adult immortal jelly that’s starving or injured can transform itself back into a polyp, its juvenile stage. We talked about it in episode 343 in some detail, which was recent enough that I won’t cover it again in this episode. Scientists are currently studying the jelly to learn more about how it accomplishes this transformation and how long it can really live.

So far all the animals we’ve talked about, except the immortal jellyfish, are vertebrates. It’s when we get to the invertebrates that we find animals with the longest lifespans. The ocean quahog, a type of clam that lives in the North Atlantic Ocean, grows very slowly compared to other clams, and populations that live in cold water can live a long time. Sort of like tree rings, the age of a clam can be determined by counting the growth rings on its shell, and a particular clam dredged up from the coast of Iceland in 2006 was discovered to be 507 years old. Its age was double-checked by carbon-14 dating of the shell, which verified that it was indeed just over 500 years old when it was caught and died. Researchers aren’t sure how long the quahog can live, but it’s a safe bet that there are some alive today that are older than 507 years, possibly a lot older.

The real long-lived animals are very simple ones, especially sponges and corals. Some species of both can live for thousands of years. Various kinds of mollusks and at least one urchin can live for hundreds of years.

It’s probable that there are lots of other animals that routinely outlive humans, we just don’t know that they do. Scientists don’t always have a way to check an animal’s age, or they don’t think to do so while studying an organism. There are also plenty of animals that we just don’t know exist, especially ones that live in the ocean. For example, a species of tube worm named Escarpia laminata wasn’t even discovered until 1985, and it wasn’t until 2017 that scientists realized it lived for hundreds or even thousands of years.

The tube worm doesn’t have a common name, since it lives in the deepest parts of the Gulf of Mexico around what are called cold seeps, so no one ever needed to refer to it until it was discovered by scientists. A cold seep isn’t actually cold, it just isn’t as hot as a hydrothermal vent. In a cold seep, oil and methane are released into the ocean from fissures in the earth’s crust. Life forms live around these areas that live nowhere else in the world.

Many tube worms can grow quite long and can live over 250 years, with the giant tube worm growing almost 10 feet long, or 3 meters. Escarpia laminata is smaller, typically only growing about half that length. In a study published in 2017, a team of scientists estimated that it routinely lives for 250 to 300 years and potentially much, much longer. A tube worm doesn’t actually eat; instead, it forms a symbiotic relationship with bacteria that live in its body. The bacteria have a safe place to live and the tube worm receives energy from the bacteria as they oxidize sulfur released by the cold seeps. The tube worm, in other words, lives a stress-free life with a constant source of energy, and nothing much wants to eat it. The limit to its life may be the limit of the cold seeps where it lives. Cold seeps don’t last forever, although many of them remain active for thousands of years.

Humans are probably the longest-living terrestrial mammal. This may not seem too impressive compared to the animals we’ve talked about in this episode, but our lives are a whole lot more interesting than a tube worm’s.

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

Thanks for listening!

Episode 325: The Burrunjor

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We have merch available again!

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

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

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

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Thanks for listening!

Episode 299: Entombed in Stone!

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This week’s episode rates one out of five ghosts on the spookiness scale. It’s not too spooky unless the thought of being ENTOMBED IN STONE creeps you out! Which it might, if you are a frog.

Further reading:

A Tenacious Pterodactyl

Further watching:

“One Froggy Evening”

A frog supposedly found mummified in a stone:

The Texas horned lizard kind of looks like a pointy toad with a tail:

Show transcript:

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

We’re getting really close to Halloween and our 300th episode, and it’s going to be a spooky one! This week, though, I rate this episode as one ghost out of five on our spookiness scale, meaning it’s not very spooky at all…unless you’re a frog!

Most of us know this story. A worker helping to demolish a building finds a mysterious box hidden in the building’s cornerstone. He opens the box and discovers a living frog—a frog that can sing and dance! But only when no one else is looking!

That’s the classic Looney Tunes cartoon “One Froggy Evening,” and while it’s really funny, it’s also based on many stories about frogs, toads, and other animals supposedly discovered entombed but alive, or only recently dead, in clay, bricks, tree trunks, coal, and even rocks.

For example, in 1782, the American politician and naturalist Benjamin Franklin was living in France, and while he was there he heard about some workmen in a quarry who had found some living toads encased in stone. I’ll quote from Franklin’s writing:

“At Passy, near Paris, April 6th, 1782, being with M. de Chaumont, viewing his quarry, he mentioned to me, that the workmen had found a living toad shut up in the stone. On questioning one of them, he told us, they had found four in different cells which had no communication; that they were very lively and active when set at liberty; that there was in each cell some loose, soft, yellowish earth, which appeared to be very moist. We asked, if he could show us the parts of the stone that formed the cells. He said, No; for they were thrown among the rest of what was dug out, and he knew not where to find them. We asked, if there appeared any opening by which the animal could enter. He said, No. […] We asked, if he could show us the toads. He said, he had thrown two of them up on a higher part of the quarry, but knew not what became of the others.

“He then came up to the place where he had thrown the two, and, finding them, he took them by the foot, and threw them up to us, upon the ground where we stood. One of them was quite dead, and appeared very lean; the other was plump and still living. The part of the rock where they were found, is at least fifteen feet below its surface, and is a kind of limestone. A part of it is filled with ancient seashells, and other marine substances. If these animals have remained in this confinement since the formation of the rock, they are probably some thousands of years old.”

Since limestone generally takes about a million years to form, and requires considerable pressure and lots of chemical reactions to do so, we can be certain that the toads were not in the limestone for all that long. But limestone is porous, and the mention of damp yellow earth inside the capsules of stone suggests that there were significant fissures in the stones where the toads were found. Limestone dissolves in water, although it takes a long time. That’s how caves form. Maybe over many years, tiny cracks and holes had formed in the limestone, large enough for some well developed tadpoles or young toads to end up in the holes, maybe during a rainstorm or flood.

Then again, the whole thing might have been a mistake. The toads might not have actually been inside the stones, only nearby when the stones were broken open. The workers might have thought they were inside. Or it might just have been a hoax made up by a bored quarry worker.

Stories of animals found encased in stone or other impossible conditions go back hundreds of years, in many parts of the world, but for some reason they got really popular around the mid-19th century in England. Suddenly people were finding toads and other animals in all sorts of weird places, or said they had. The Rev. Robert Taylor of St. Hilda’s Church, Hartlepool, for instance, exhibited a toad and the stone it was found in, with the chamber inside the stone being exactly the size and shape of the toad before it was broken open and freed in April 1865. But a geologist who examined the stone found obvious chisel marks where it had been hollowed out and shaped to look like the toad had been inside.

It wasn’t just toads found in rocks, of course, although those were the most popular. A mouse was supposedly found in a rock in 1803, three salamanders of a presumed extinct species were supposedly found in a rock sometime before 1818, and a horned toad was supposedly found in a building cornerstone in 1928. The horned toad is actually a lizard, in this case a Texas horned lizard that lives in various parts of the south-central United States and northeastern Mexico.

The Texas horned lizard does actually resemble a toad in some ways. Its body is broad and rounded and its face has a blunt, froglike snout. A big female grows about 5 inches long, or almost 13 cm, not counting its tail, while males are smaller. It’s covered with little pointy scales, and if it feels threatened, it will puff up its body so that the scales stick out even more. It also has true horns on its head, little spikes that are formed by projections of its skull.

The Texas horned lizard eats insects, especially a type of red ant called the harvester ant. The harvester ant is venomous but the horned lizard is resistant to the venom and is specialized to eat lots and lots of the ants. Its esophagus produces lots of mucus when it’s eating, which collects around the ants and stops them from being able to bite before they die.

The horned lizard supposedly found in a cornerstone of a building was nicknamed Ol’ Rip after Rip Van Winkle, the main character in a short story by Washington Irving who fell asleep and woke up 20 years later. Ol’ Rip the Texas horned lizard was supposedly placed into the hollow cornerstone brick as part of a time capsule when the Eastland County Courthouse was being built in 1897.

In 1928, the courthouse was torn down and a newspaper reporter advertised the opening of the time capsule, including the story about the horned lizard. Sure enough, a live horned lizard was removed from the cornerstone when it was opened, which by the way was the inspiration for the “One Froggy Evening” cartoon.

Ol’ Rip became a celebrity and was displayed all over the United States, and the Texas horned lizard became such a popular pet that the population declined severely, since people went out and caught them to sell as pets. Since the horned lizard eats a lot of insects that damage crops, its decline in numbers actually led to farmers losing money to insect damage. The Texas horned lizard is still endangered, for that matter, and is now a protected species that isn’t allowed to be kept as a pet. Ol’ Rip died less than a year after he was supposedly discovered in the cornerstone.

Even at the time, a lot of people were skeptical that Ol’ Rip had really been in the cornerstone brick for 31 years. It’s much more likely that one of the officials presiding over the time capsule’s opening brought a horned lizard with him and pretended to find it in the brick.

For one thing, the Texas horned lizard needs bright sunshine to survive. Its body can only produce vitamin D when it gets a lot of sunshine, and without vitamin D it will eventually die. It spends a lot of time sunbathing and while it does dig a burrow to sleep in at night, as soon as the sun’s out in the morning, the lizard comes out to bask in the sunshine. A Texas horned lizard trapped in a brick without food, water, air, or sunshine wouldn’t survive long.

The weirdest animal ever supposed to have been found in a stone was reported in the Illustrated London News in 1856. According to the article, during the construction of a railway tunnel in France, a huge block of stone was dislodged with dynamite. The workers were breaking it into smaller pieces when they exposed a chamber inside the rock. A creature emerged that looked something like an enormous bat, but was obviously not a bat. It had a long neck, sharp teeth in its mouth, four long legs with long claws on its talons, and its front and hind legs were connected with flying membranes. It was black with bare skin.

The animal shook its wings but promptly dropped dead, and was sent to a naturalist who identified it as Pterodactylus anas, which had died 64 million years before. Its wingspan was measured as 10 feet, 7 inches across, or 3 meters, 22 cm.

There is no species of pterodactyl named Pterodactylus anas, but anas is Latin for duck. The word for duck in French is canard, which in English means something more like “a hoax or tall tale.”

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

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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 278: Gender Diverse Animals

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This week is Connor’s episode, and we’re going to learn about some animals that don’t conform to “typical” gender roles, one way or another.

I’ll be at ConCarolinas this week, from June 3 through 5, including recording a live crossover episode with Arcane Carolinas!

Further reading:

Species of algae with three sexes that all mate in pairs identified in Japanese river

How a microbe chooses among seven sexes

Facultative Parthenogenesis in California Condors

The sparrow with four sexes

Chinstrap penguins make good dads:

Laysan albatrosses make good moms:

Black swans make good dads:

Some rams really like other rams (photo by Henry Holdsworth):

New Mexico whiptail lizards are all females:

California condor females don’t always need a male to produce fertilized eggs:

Clownfish change sex under some circumstances:

The white-throated sparrow essentially has four sexes:

You are awesome (photo by By Eric Rolph)!

Show transcript:

“Hey y’all, this is Connor. Welcome to a very special Pride Month edition of the Strange Animals Podcast.”

This week we have Connor’s episode! We decided to make it the very last episode in our Kickstarter month so that it’s as close to the month of June as possible, because June is Pride Month and our episode is about gender-diverse animals! Don’t worry, parents of very young children, we won’t be discussing mating practices except in very general terms.

Pride month celebrates people’s differences when it comes to gender expression and sexuality. That’s why its symbol is the rainbow, because a rainbow is made up of all different colors the same way there are different kinds of people. Sometimes people get angry when they hear about Pride month because they think there are only two genders, and that those two genders should only behave in certain ways. Pffft. That’s not even true when it comes to animals, and humans are a lot more socially complicated.

For instance, let’s start by talking about a humble creature called algae. If you remember episode 129, about the blurry line between animals and plants, you may remember that algae isn’t actually a plant or an animal. Some species resemble plants more than animals, like kelp, but they’re not actually plants. In July of 2021, scientists in Japan announced that a species of freshwater algae has three sexes: male, female, and bisexual. All three sexes can pair up with any of the others to reproduce and their offspring may be male, female, or bisexual at random.

Even though the algae has been known to science for a long time, no one realized it has three sexes because most of the time, algae reproduces by cloning itself. The research team thinks that a lot of algae species may have three sexes but researchers just haven’t been looking for it.

Yes, I realize that was a weird place to start, but it’s also fascinating! It’s also not even nearly as complicated as a protozoan called Tetrahymena thermophila, which has seven sexes.

Let’s look at a bird next, the penguin. You’ve probably heard of the book And Tango Makes Three, about two male penguins who adopt an egg and raise the baby chick together. For some reason some people get so angry at those penguins! Never trust someone who doesn’t like baby penguins, and never trust someone who thinks animals should act like humans. The events in the book are based on a true story, where two male chinstrap penguins in New York’s Central Park Zoo formed a pair bond and tried to hatch a rock, although they also tried to steal eggs from the other penguins. A zookeeper gave the pair an extra penguin egg to hatch instead.

The most interesting thing about the story is that same-sex couples are common among penguins, in both captivity and in the wild, among both males and females. Since penguins sometimes lay two eggs but most species can only take care of one chick properly, zookeepers often give the extra eggs to same-sex penguin pairs. The adoptive parents are happy to raise a baby together and the baby is more likely to survive and be healthy. Occasionally a same-sex penguin couple will adopt an egg abandoned by its parents.

If you remember episode 263 a few months ago, where we talked about animals that mate for life, you may remember the Laysan albatross. In that episode we learned about a specific Laysan albatross named Wisdom, the oldest wild bird in the world as far as we know. While I was researching Wisdom, I learned something marvelous. As many as 30% of all Laysan albatross pairs are both females. Sometimes one of the females will mate with a male and lay a fertilized egg, and then both females raise the baby as a couple. Sometimes one of the females lays an unfertilized egg that doesn’t hatch. There are many more Laysan albatross females than males, which may be the reason why females form pairs, but it’s perfectly normal behavior. It’s also been a real help to conservationists. Sometimes an albatross pair will nest in an area that’s not safe, like on an airfield. Instead of leaving the egg to be smashed by an airplane, conservationists take the fertilized egg from the unsafe nest and use it to replace the unfertilized egg of a female pair. The egg is safe and the chick has adoptive parents who raise it as their own.

Many other birds develop same-sex pairs too. This is especially common in the black swan, where up to a quarter of pairs are both male. One or both of the males will mate with a female, but after she lays her eggs the males take care of them and the cygnets after they hatch. Cygnets raised by two dads are much more likely to survive than cygnets raised by one mom and one dad. The males are stronger and more aggressive, so they can defend the nest and babies more effectively.

Birds aren’t the only animals that form same-sex pair bonds. Many mammals do too. It’s been documented in the wild in lions, elephants, gorillas, bonobos, dolphins, and many more. In species that don’t typically form pair bonds, homosexual behavior is still pretty common. It’s so common among domestic sheep that shepherds have to take into account the fact that up to 10% of rams prefer to mate with other rams instead of with ewes. Some rams show attraction to both males and females. This happens in wild sheep too, where rams may court other rams the same way they court ewes. Some ewes also show homosexual behavior.

The New Mexico whiptail is a lizard that lives in parts of the southwestern United States and northern Mexico. It can grow over nine inches long, or 23 cm, and is black or brown with yellow racing stripes. It eats insects and is an active, slender lizard that’s common throughout its range. And every single New Mexico whiptail lizard is a female.

The lizards reproduce by a process called parthenogenesis. That basically means an animal reproduces asexually without needing to have its eggs fertilized. The lizards do mate, though, but not with males. Females practice mating behaviors with each other, which researchers think causes a hormone change that allows eggs to develop. Females who don’t mate don’t develop eggs.

Female birds can sometimes reproduce asexually too. It’s been documented in turkeys, chickens, pigeons, finches, and even condors. A study published in late 2021 detailed two instances of parthenogenesis in California condors in a captive breeding program. In both cases the females were housed with their male mates, and in both cases the pairs had produced offspring together before. But in both cases, for some reason the females laid eggs that hatched into chicks that were genetically identical to the mothers. It’s possible parthenogenesis is even more common in birds than researchers thought.

In many species of reptile, whether a baby is a male or female depends completely on how warm its egg gets during incubation. For example, the American alligator. The mother gator builds a nest of plant material and lays her eggs in it. As the plant material decays, it releases heat that keeps the eggs warm. How much heat is generated depends on where the mother alligator builds her nest and what plants she uses, which in turns affects the eggs. If the temperature in the nest is under 86 degrees Fahrenheit, or 30 Celsius, during the first few weeks of incubation, most or all of the eggs will hatch into females. If the temperature is 93 F or 34 C, most or all of the eggs will hatch into males. If the temperature is between the two extremes, there will be a mix of males and females, although usually more females.

Because climate change has caused an overall increase in temperatures across the world, some already vulnerable reptile populations, especially sea turtles, are hatching almost all males. Conservationists have to dig up the eggs and incubate them at a cooler temperature in captivity, then release the babies into the ocean when they hatch.

Other animals change from male to female or vice versa, depending on circumstances. The clownfish, for example. Clownfish start out life as males but as they grow up, most become females, although only the dominant pair in a colony actually reproduces. Clownfish live in colonies led by the largest, most aggressive female, with the largest, most aggressive male in the group as her mate. If something happens to her, her former mate takes her place, becoming a female in the process. The largest juvenile male then becomes her mate and remains male even though he puts on a growth spurt to mature quickly. If Finding Nemo was scientifically accurate, it would have been a much different movie.

Another group of fish that live around reefs are wrasses, which includes the famous cleaner fish that cleans parasites and dead tissue off of larger fish. Wrasses hatch into both males and females, but the males aren’t the same type of males that can breed. Those develop later. When the dominant breeding male of the group dies, the largest female or the largest non-breeding male then develops into a breeding male. But sometimes a non-breeding male will develop into a female instead.

The term for an animal that changes sex as part of its natural growth process is sequential hermaphroditism. It’s common in fish and crustaceans in particular. Other animals have the reproductive organs of both a male and a female, especially many species of snail, slug, earthworm, sea slug, and some fish. We talked about the mangrove killifish in episode 133, and in that episode I said it was the only known vertebrate hermaphrodite. That’s actually not accurate, although I was close. It’s the only known vertebrate hermaphrodite that can self-fertilize. Almost all mangrove killifish are females, although they also produce sperm to fertilize their own eggs. The eggs hatch into little clones of the mother.

We’ve talked about seahorses before too, especially in episode 130. Seahorse pairs form bonds that last throughout the breeding season. The pair participate in courtship dances and spend most of their time together. When the eggs are ready, the female deposits them in a special brood pouch in the male’s belly, where he fertilizes them. They then embed themselves in the spongy wall of the brood pouch and are nourished not only by the yolk sacs in the eggs, but by the male, who secretes nutrients in the brood pouch. So basically the male is pregnant. The female visits him every day to check on him, usually in the mornings. When the eggs hatch after a few weeks, the male expels the babies from his pouch and they swim away, because when they hatch they are perfectly formed teeny-tiny miniature seahorses.

Let’s finish with a little songbird that’s common throughout eastern North America, the white-throated sparrow. It has a white patch on its throat and a bright yellow spot between the eye and the bill. There are two color morphs, one with black and white stripes on its head, one with brown and tan stripes on its head. Both males and females have these head stripes. The male sings a pretty song that sounds like this:

[white-throated sparrow call]

A 30-year study into white-throated sparrow genetics has revealed some amazing things. The color morphs are due to a genetic difference that affects a lot more than just feather colors. Black morph males are better singers, but they don’t guard their territory as well or take care of their babies as well as brown morphs do. They also aren’t as faithful to their mates as the brown morph males, which are fully monogamous and are diligent about helping take care of their babies. Despite their differences in raising offspring, both morphs are equally successful and equally common.

All this seems to be no big deal on the surface, maybe just pointing to the possibility that the species is in the process of splitting into two species or subspecies. But that’s not the case.

Black morphs always mate with brown morphs. A black morph male will always have a brown morph mate, and vice versa. Genetically, the two morphs are incredibly different—so different, in fact, that they seem to be developing a fully different set of sex chromosomes. In other words, there are male and female black morph birds and male and female brown morph birds that are totally different genetically, but still members of the same species that only ever breed with each other. In essence, the white-throated sparrow has four sexes.

Usually I try to end episodes with something funny, but today I’m going to speak directly to you. Yes, you! If you’re listening to this or reading the transcript, my words are meant just for you. You are an amazing person and I love you. You deserve to be happy. If anyone has ever told you there’s something wrong with the way you are, or the way you wish you were or want to be, they’re wrong. They probably also don’t like penguins, so you don’t have to believe anything they say. If you’ve ever read books by Terry Pratchett, you may recognize this quote: “Be yourself, as hard as you can.”

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!