Category Archives: North America

Episode 431: The New Dire Wolf

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Thanks to Jayson for suggesting this week’s topic, the new “dire wolf”! Also, possibly the same but maybe a different Jayson is the youngest member of the Cedar Springs Homeschool Science Olympiad Team, who are on their way to the Science Olympiad Nationals! They’re almost to their funding goal if you can help out.

Further reading:

Dire wolves and woolly mammoths: Why scientists are worried about de-extinction

The story of dire wolves goes beyond de-extinction

These fluffy white wolves explain everything wrong with bringing back extinct animals

Dire Wolves Split from Living Canids 5.7 Million Years Ago: Study

This prehistoric monster is the largest dog that ever lived and was able to crush bone with its deadly teeth – but was wiped out by cats

“Dire wolf” puppies:

An artist’s interpretation of the dire wolf (red coats) and grey wolves (grey coats) [taken from fourth link above]:

The “mammoth fur” mice:

Show transcript:

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

This week we have a suggestion from Jayson, who wants to learn about the so-called “new” dire wolf.

Before we get started, a big shout-out to another Jayson, or maybe the same one I’m honestly not sure, who is the youngest member of the Cedar Springs Homeschool Science Olympiad Team. They’ve advanced to the nationals! There’s a link in the show notes if you want to donate a little to help them with their travel expenses. This is a local team to me so I’m especially proud of them, and not to brag, but I’ve actually met Jayson and his sister and they’re both smart, awesome kids.

Now, let’s find out about this new dire wolf that was announced last month. In early April 2025, a biotech company called Colossal Biosciences made the extraordinary claim that they had produced three dire wolf puppies. Since dire wolves went extinct around 13,000 years ago, this is a really big deal.

Before we get into the details of Colossal’s claim, let’s refresh our memory about the dire wolf. We talked about it in episode 207, so I’ve taken a lot of my information from that episode.

According to a 2021 study published in Nature, 5.7 million years ago, the shared ancestor of dire wolves and many other canids lived in Eurasia. Sea levels were low enough that the Bering land bridge, also called Beringia, connected the very eastern part of Asia to the very western part of North America. One population of this canid migrated into North America while the rest of the population stayed in Asia. The two populations evolved separately until the North American population developed into what we now call dire wolves. Meanwhile, the Eurasian population developed into many of the modern species we know today, and some of those eventually migrated into North America too.

By the time the gray wolf and coyote populated North America, a little over one million years ago, the dire wolf was so distantly related to it that even when their territories overlapped, the species avoided each other and didn’t interbreed. We’ve talked about canids in many previous episodes, including how readily they interbreed with each other, so for the dire wolf to remain genetically isolated, it was obviously not closely related at all to other canids at that point.

The dire wolf looked a lot like a grey wolf, but researchers now think that was due more to convergent evolution than to its relationship with wolves. Both lived in the same habitats: plains, grasslands, and forests. The dire wolf was slightly taller on average than the modern grey wolf, which can grow a little over three feet tall at the shoulder, or 97 cm, but it was much heavier and more solidly built. It wouldn’t have been able to run nearly as fast, but it could attack and kill larger animals.

The dire wolf went extinct around 13,000 years ago, but Colossal now claims that they’re no longer extinct. There are now exactly three dire wolves in the world, two males and a female, born to two different dogs who acted as surrogate mothers. But are these really dire wolves, or are they something else?

Colossal’s scientists claim that the 2021 Nature study that determined gray wolves and dire wolves weren’t closely related and couldn’t interbreed was based on poor-quality DNA studies. They redid the genetic scans and determined that dire wolves were more wolf-like than the 2021 study thought. But the 2021 study was published in the foremost peer-reviewed journal in the scientific world. Colossal’s study hasn’t been published at all.

Extraordinary claims require extraordinary evidence. In other words, until a study is published in a respected peer-reviewed journal that contradicts the 2021 Nature study, all the genetic evidence we have now points to dire wolves and gray wolves being extremely genetically different.

Colossal’s scientists made 20 edits to 14 gray wolf genes to make the puppies more similar to dire wolves in size, with white coats even though there’s no evidence that real dire wolves were white. Colossal claims that the genomes of grey wolves and dire wolves are 99.5% identical, but those 20 changes are out of 12,235,000 genetic differences. Genetically these puppies are just modern grey wolves.

The biggest problem with the claim that the puppies are actually dire wolves is that it implies that bringing back an extinct species is really easy. Not only can this make people think that extinction isn’t a big deal after all, it also ignores the issues that make animals go extinct in the first place, especially recently, like pollution, habitat loss, climate change, invasive species, and over-hunting or capture of wild animals to sell as exotic pets.

In the very first, very terrible Strange Animals Podcast episode, I talked about the quagga, a species of zebra from South Africa that went extinct very recently due to human causes. I was excited about the de-extinction attempts for that species, which mostly involved breeding zebras with the most quagga genetic material to select for quagga-like traits. I still think this is a good project, since the quagga’s ecosystem is still in place and still has a quagga-shaped hole in it. Colossal has also done good work with red wolves in North America, helping to keep that critically endangered species genetically healthy.

Also in an early episode, I talked about Colossal’s de-extinction plans for the mammoth. I was all for that too, tongue-in-cheek, because I said I wanted a pet mammoth. Now I’ve changed my mind. Awesome as it would be to see real live mammoths, there’s not any real habitat left for them. Between climate change, habitat loss due to human activity, and more than ten thousand years of evolution of other animals to move into the mammoth’s empty ecological niche, where does Colossal plan to put its mammoths? We don’t even have safe habitats for elephants anymore, which are still around.

Earlier this year, Colossal announced another genetically modified animal, mice with long golden-brown fur inspired by woolly mammoth fur. Mammoths were highly adapted for cold far beyond long fur, while modern elephants are highly adapted for hot climates. If Colossal’s mammoths are anything like its so-called dire wolves, they’ll be editing genes to change appearance, not anything else. That’s unethical, basically taking an endangered heat-adapted animal, giving it a heavy coat, and sticking it into a cold climate. It will have no herd mates and no knowledge of how to survive in the wild in a climate it was never intended to live in, meaning it will be dependent on human help. Once the novelty of “oh look, a furry elephant” wears off, and Colossal either goes out of business or moves on to the next big thing, what will happen to the mammoth?

That’s one of the concerns about the new dire wolves. They don’t have a wolf family. They’re completely dependent on humans and will never be able to survive in the wild, even if they were allowed to try.

Let’s return to extinct canids to finish on a brighter note, something that Richard from NC brought to my attention recently. It’s an animal called epicyon, a canid that may have lived as recently as 5 million years ago in North America. It’s the largest canid ever discovered, around 3 feet tall, or 90 cm, at the shoulder and as much as 8 feet long, or 2.5 meters. It probably weighed as much as a small bear, and it was strong and powerful so that it was probably more bear-like or lion-like in body shape than wolf-like.

It had a short, powerful muzzle and strong jaws with huge teeth meant for crushing bone, similar to modern hyenas. It wasn’t anywhere near as fast a runner as modern wolves, but it could probably move pretty fast when it needed to. Some scientists think it was a pack animal, but it may have been an ambush predator instead of hunting in packs like wolves and other modern canids do.

Epicyon probably preyed on megaherbivores like camels, horses, pronghorn, rhinoceroses, and peccaries, all of which were common in North America several million years ago. It probably also scavenged a lot of its food, since it could break bones other animals couldn’t. We’re not sure why epicyon went extinct, but some scientists suggest it was out-competed by saber-tooth cats and more modern canids–including the dire wolf.

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 430: The Fake and the Real Coelacanth

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This week we examine two recent articles about coelacanth discoveries. Which one is real and which one is fake?!

Further reading:

Fake California Coelacanth

First record of a living coelacanth from North Maluku, Indonesia

A real coelacanth photo:

A fake coelacanth photo (or at least the article is a fake) [photo taken from the first article linked above]:

A real coelacanth photo [photo from the second article linked above]:

Show transcript:

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

I had another episode planned for this week, but then I read an article by geologist Sharon Hill and decided the topic she researched was so important we need to cover it here. No, it’s not the dire wolf—that’s next week. It’s the coelacanth.

We talked about the coelocanth way back in episode two, with updates in a few later episodes. Because episode two is so old that it’s dropped off the podcast feed, and to listen to it you have to actually go to the podcast’s website, I’m going to quote from it extensively here.

In December of 1938, a museum curator in South Africa named Marjorie Courtenay Lattimer got a message from a friend of hers, a fisherman named Hendrick Goosen, who had just arrived with a new catch. Lattimer was on the lookout for specimens for her tiny museum, and Goosen was happy to let her have anything interesting. Lattimer went down to the dock. Then she noticed THE FISH.

It was five feet long, or 1.5 meters, blueish with shimmery silvery markings, with strange lobed fins and scales like armored plates. She described it as the most beautiful fish she had ever seen. She didn’t know what it was, but she wanted it. She took the fish back to the museum in a taxi and went through her reference books to identify it.

Imagine it. She’s flipped through a couple of books but nothing looks even remotely like her fish. Then she turns a page and there’s a picture of the fish–but it’s extinct. It’s been extinct for some 66 million years. But it’s also a very recently alive fish resting on ice in the back of her museum.

Lattimer sketched the fish and sent the drawing and a description to a professor at Rhodes University, J.L.B. Smith. But Smith was on Christmas break and didn’t get her message until January 3rd. In the meantime, Lattimer’s museum director told her the fish was a grouper and not worth the ice it was lying on.

December is the middle of summer in South Africa, so to keep the fish from rotting away, she had it mounted. Then Smith sent her a near-hysterical cable that read, “MOST IMPORTANT PRESERVE SKELETON AND GILLS.” Oops.

Smith got a little obsessed about finding another coelacanth. He offered huge rewards for a specimen. But it wasn’t until December of 1952 that a pair of local fishermen on the island of Anjuan, about halfway between Tanzania and Madagascar, turned up with a fish they called the gombessa. It was a second coelacanth.

Everyone was happy. The fishermen got a huge reward—a hundred British pounds—and Smith had an intact coelacanth. He actually cried when he saw it.

Most people have heard of the coelacanth because its discovery is such a great story. But why is the fish such a big deal?

The coelacanth isn’t just a fish that was supposed to be extinct and was discovered alive and well, although that’s pretty awesome. It’s a strange fish, more closely related to mammals and reptiles than it is to ordinary ray-finned fish. The only living fish even slightly like it is the lungfish, which we talked about in episode 55.

While the coelacanth is unique in a lot of ways, it’s those lobed fins that are really exciting. It’s not a stretch to say its paired fins look like nubby legs with frills instead of digits. Until DNA sequencing in 2013, many researchers thought the coelacanth was a sort of missing link between water-dwelling animals and those that first developed the ability to walk on land. As it happens, the lungfish turns out to be closer to that stage than the coelacanth, and both the lungfish and the coelacanth had already split off from the shared ancestor of marine and terrestrial organisms when they evolved around 400 million years ago. But for scientists in the mid-20th century, studying a fish that looked like it had little legs must have been electrifying.

But this fish story isn’t over yet. In 1997, a marine biologist on honeymoon in Indonesia found a coelacanth in a local market. And it was a different species of coelacanth. Can you imagine a better wedding gift?

Coelacanths are placid fish who do a lot of drifting, although their eight marvelous fins make them very maneuverable. They stay close to the coast and prefer rocky areas. They especially love underwater caves. They hunt for smaller fish and cephalopods like squid at night and rest in caves or hidden among rocks during the day. Sometimes sharks eat them, but for the most part coelacanths lead comfortable lives, floating around eating stuff. Sometimes they float around tail up or even upside down because they just don’t care.

Coelacanths have since been discovered in the western Indian Ocean, off the coast of Madagascar, and a few other places. I finished episode two by saying, “So far, living coelacanths have mostly been found off the coast of Africa, but they’re much more widely spread in the fossil record. Rumors of coelacanths in other places, like the Gulf of Mexico or around Easter Island, keep popping up. Maybe one day another population of these awesome fish will be discovered.”

And in late April 2025, it seemed that my hope had come true. An article was released by a website called Animals Around the Globe, detailing a new discovery of a coelacanth off the coast of San Diego, California!

Now, I missed that article but Sharon Hill didn’t. She’s a geologist whose work I follow and mention here occasionally. She likes to post about cryptids and other mysteries and dig into the real science behind reports, and she suspected right away that there was something fake about the San Diego coelacanth. There’s a link in the show notes to her article, which is worth reading. For one thing, she explains how she did the research to determine whether the article was real.

Her first step was to look for other articles about the finding. Animals Around the Globe isn’t a scientific site, just a blog that posts about animals. A new species of coelacanth, especially one found in North America, would be a HUGE big deal in the scientific community, so there should be lots of articles about it. But Sharon didn’t find anything.

Her next step was to contact the two institutions referenced in the article, the Scripps Institution of Oceanography and the Monterey Bay Aquarium Research Institute. Scripps wrote back first and said the article was a fake. Sharon suspects the article was AI generated. The blog that posted it gets money from advertising, and the more people click through to read the article, the more money they make. That’s why I’m not linking to that article from the show notes.

As it happens, on the same day that that article was published, another article about the coelacanth was published, this one in Nature Scientific Reports. It’s titled “First record of a living coelacanth from North Maluku, Indonesia,” and I do link to it in the show notes because it’s a real sighting and an article written by real scientists, not AI.

In October 2024 a team of scientists were doing deep diving off the coast of North Maluku, Indonesia, on a submerged volcanic slope where they suspected coelacanths were living. It was a dangerous dive because they had to descend so deep, so it required them to use a decompression stage on the way back to the surface. A pair of divers were on their way to the decompression site when they saw a big fish hovering over a boulder. It was a coelacanth that they estimated as being about 5 feet long, or 1.5 meters!

It swam away slowly, but the next morning the divers returned and saw it again. Because coelacanths are gray with a pattern of white dots, and each dot pattern is unique, they knew it was the same fish. They were able to get more photos and video. The most important thing, though, is that while coelacanths have been found in other parts of Indonesia, they hadn’t been found in this particular area. Live individuals also hadn’t ever been seen by actual divers, just ROVs.

The more we know about these amazing fish, the better they can be protected. Fake articles only bring confusion and doubt.

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 429: Foxes!

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Thanks to Katie, Torin, and Eilee for suggesting this week’s topic, foxes!

Further reading:

Meet the Endangered Sierra Nevada Red Fox

Long snouts protect foxes when diving headfirst in snow

Black bears may play important role in protecting gray fox

The red fox:

A black and gold Sierra Nevada red fox [photo taken from the first link above]:

The extremely fluffy Arctic fox:

The gray fox [photo by VJAnderson – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=115382784]:

Show transcript:

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

This week we have an episode about foxes, a suggestion by Katie, and we’ll talk about fox species suggested by Torin and Eilee.

Foxes are omnivorous canids related to dogs and wolves, and just to be confusing, male foxes are sometimes called dogs. Female foxes are vixens and baby foxes are cubs or kits. But even though foxes are related to dogs and wolves, they’re not so closely related that they can interbreed with those other canids. Plus, of course, not every animal that’s called a fox is actually considered a fox scientifically.

The largest species of fox is the red fox, which also happens to be the one most people are familiar with. It’s common throughout much of North America, Eurasia, and the Middle East, and even parts of northern Africa. It’s also been introduced in Australia, where it’s an invasive species. It’s a rusty-red in color with black legs and white markings, including a white tip to the tail. It has large pointed ears and a long narrow muzzle.

There are lots of subspecies of red fox throughout its natural range, including one suggested by Eilee, the Sierra Nevada red fox. It lives in the Sierra Nevada and Oregon Cascades mountain ranges in the western United States, in parts of California, Nevada, and Oregon. It’s smaller than the red fox and some individuals are red, some are black and gold, and some are a mix of red and gray-brown. Its paws are covered with long hair that protects the paw pads from snow, and its coat is thick.

The Sierra Nevada red fox was first identified as a subspecies in 1937, but it took more than half a century until any scientists started studying it. It used to be common throughout the mountain ranges where it lives, but after more than a century of trapping for fur and shooting it for bounty, it’s one of the rarest foxes in the world. Fewer than 100 adults are known to survive in the wild, maybe even fewer than 50.

For a long time, scientists thought the Sierra Nevada red fox had been extirpated from California, and that it might even be completely extinct. Then a camera trap got pictures of one in 2010. It’s fully protected now, so hopefully its numbers will grow.

Torin suggested we learn about the Arctic fox, which lives in far northern areas like Greenland, Siberia, Alaska, and parts of northern Canada. The Arctic fox’s muzzle is relatively short and its ears are rounded, and it also has a rounder body and shorter legs than other foxes. This helps keep it warm, since it has less surface area to lose body heat.

During the summer, the Arctic fox is brown and gray, while in winter it’s white to blend in with the snowy background. There are some individuals who are gray or brown-gray year-round, although it’s rare. The Arctic fox’s fur is thick and layered to keep it warm even in bitterly cold weather, and like the Sierra Nevada red fox, it has a lot of fur on its feet.

The Arctic fox is omnivorous like other foxes, although in the winter it mostly eats meat. In summer it eats bird eggs, berries, and even seaweed along with fish and small animals like lemmings and mice. It also eats carrion from dead animals and what’s left from a polar bear’s meal. It has such a good sense of smell that it can smell a carcass from 25 miles away, or 40 km. Its hearing is good too, which allows it to find mice and other animals that are traveling under the snow. Like other foxes, it will poke its nose into the snow quickly to grab the little animal, an activity called mousing. A study from 2024 revealed that the fox’s snout shape helps keep it from getting injured in deep and compacted snow.

The grey fox lives throughout North and Central America, although it’s less common than it used to be due to habitat loss and hunting by humans. It’s a grizzled gray in color with reddish or tan legs, and a black stripe down its tail ending in a black tail tip.

It’s actually not that closely related to what are called true foxes. Its pupils are rounded like a dog’s instead of slit like other foxes, which have eyes that resemble cats’ eyes. The grey fox also has hooked claws that allow it to climb trees like a cat, and when it’s in a tree it can climb around in it just fine. A vixen may make her den in the hollow part of a tree to have her babies, sometimes as much as 30 feet, or 9 meters, above the ground, although most of the time gray foxes den on the ground, in a burrow, hollow log, or even in an abandoned human building.

The gray fox is small, not much bigger than a domestic cat, and it eats a lot of the same things that coyotes eat. If a coyote feels like a grey fox is encroaching on its territory, the coyote will kill the fox. Naturally, foxes are cautious around coyotes as a result. A study published in 2021 discovered that in areas where black bears live alongside coyotes and gray foxes, the foxes spend a lot of time hanging out near bears. In winter when the bears are hibernating, the foxes leave because coyotes will move into the area until the bears re-emerge in spring. Coyotes are afraid of bears, so the presence of bears protects the foxes as long as the fox doesn’t annoy the bear. I feel like this would make a great basis for a cartoon.

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 426 Lots of Little Birds

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Thanks to Murilo, Alexandra, and Joel for their suggestions this week!

The bird sounds in this episode come from xeno-canto, a great resource for lots of animal sounds!

A cactus wren [picture by Mike & Chris – Cactus WrenUploaded by snowmanradio, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=15876953]:

The sultan tit [photo by By Dibyendu Ash – CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=72070998]:

A female scarlet tanager [photo by Félix Uribe, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=81340425]. The male is red with black wings:

The Northern cardinal:

The yellow grosbeak [photo by Arjan Haverkamp – originally posted to Flickr as 2008-08-23-15h00m37.IMG_4747l, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=9596644]:

The purple martin isn’t actually purple [photo by JJ Cadiz, Cajay – Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=4255626]:

The dusky thrush [photo by Jerry Gunner from Lincoln, UK Uploaded by snowmanradio, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=20762838]:

The European rose chafer, not a bird [photo by I, Chrumps, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2521547]:

Show transcript:

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

This week we’re going to learn about a lot of little birds that deserve more attention, because they’re cute and interesting. Thanks to Murilo, Alexandra, and Joel for their little bird suggestions!

All the birds we’ll talk about today are called passerines, because they belong to the order Passeriformes. They’re also sometimes referred to as perching birds or songbirds, even though not all passerines sing. Passerines are common throughout the world, with more than 6,500 species identified. I’ve seen about 150 of those species, so clearly I need to work harder as a birdwatcher.

Passerines are referred to as perching birds because of their feet. A passerine bird has three toes that point forward and another toe pointing backwards, which allows it to wrap its toes securely around a twig or branch to sit. Its legs are also adapted so that the toes automatically curl up tight when the leg is bent. That’s why a sleeping bird doesn’t fall off its branch.

Let’s start with one of Murilo’s suggestions, the wren. Wrens are birds in the family Troglodytidae, and are usually very small with a short tail, a pointy bill that turns slightly downward at the tip, and brown plumage. It mainly eats insects and larvae that it finds in nooks and crannies of trees, and many species will investigate dark places like hollow logs, the openings to caves, or your apartment if you leave the back door open on a warm day. Many sing beautiful songs and have very loud voices for such little bitty birds.

Most wrens are native to the Americas, including the canyon wren that’s native to western North America in desert areas. It’s cinnamon-brown with a white throat and an especially long bill, which it uses to find insects in rock crevices. It lives in canyons and has a more flattened skull than other wrens, which means it can get its head into crevices without hurting itself. No one has ever seen a canyon wren drink water, and scientists think it probably gets all the water it needs from the insects it eats. Where do the insects get the water they need? That’s an episode for another day.

This is what a canyon wren sounds like:

[bird sound]

Not every bird that’s called a wren is actually in the family Troglodytidae. Some just resemble wrens, like an unusual bird that Murilo brought to my attention. It’s called Lyall’s wren but it’s actually in the family Acanthisittidae, and it was once widespread throughout New Zealand. By the time it was scientifically identified and described in 1894, it was restricted to a single island in Cook Strait.

Lyall’s wren was flightless, and only five passerines are flightless as far as we know. All five were island birds who have since gone extinct, which is unfortunately the case with Lyall’s wren too. It was greenish-brown with a yellow eye stripe and its tail was just a little short nub. We don’t know much about it because between 1894 when a lighthouse was built and some families moved to the island to work at the lighthouse, bringing their housecats, and 1925 when the feral cat colony on the island was finally killed off, all the remaining Lyall’s wrens were eaten by cats or killed by people to sell as museum specimens. To be clear, it’s entirely the fault of people that the bird went extinct, because they brought the cats to the island and let them run loose. The bird probably actually went extinct in 1895, just one year after cats were introduced to the island.

Murilo also suggested some little birds called chickadees and tits, which belong to the family Paridae. They’re very small, often brightly colored or with bright white markings, with short bills that help them crack seeds open. They also eat insects. They’re not found in South America or Australia, but they’re very common in North America, Eurasia, and most of sub-Saharan Africa. Many species love to visit bird feeders, and since they’re cute and active little birds, people are happy to have them around.

Some species in this family have crests, which makes them even cuter. The tufted titmouse, which is found in eastern North America, has a little tufted crest on its head, for instance. It’s a soft gray-blue in color with patches of rusty-red under its wings, and white underneath. The gray crested tit lives in western Europe and also has a fluffy crest on its head. It’s gray-brown with a thin black and white ring around its neck and a buff-colored underside. The yellow tit lives only in forests in central Taiwan and is a gorgeous dark blue with bright yellow underneath and on its face, with a darker crest. It’s so beautiful that it’s becoming rare, since people trap the birds to sell to disreputable collectors. The sultan tit is even more spectacular, if that’s possible, since the male is black with bright yellow underparts and a bright yellow crest. It lives in parts of south Asia and some subspecies have a black crest instead.

This is what a sultan tit sounds like:

[bird sound]

Another spectacular bird is one Alexandra suggested, the summer tanager. It’s a common summer visitor in the eastern and southwestern United States that winters in Central and northern South America. The male is a bright, cheerful red all over while the female is yellow. The western tanager is a close relation that lives in western North America, wintering in Mexico. The male has a mostly black back with a yellow rump and yellow underneath, with red and orange on his face. Females are yellowy-green and gray. The scarlet tanager is also similar, although the male is red with black wings and the female is yellowy-green and gray. They eat insects and fruit, and spend a lot of time in the very tops of trees.

This is what a scarlet tanager sounds like:

[bird sound]

Despite their names, all three of these tanagers aren’t actually tanagers. Tanagers are members of the family Thraupidae and are native to central and South America. Many of them are brightly colored and absolutely gorgeous, like the red-legged honeycreeper that’s common in Central and parts of South America. The male has a black back and tail and is bright blue on the rest of his body, except for a black mask over his eyes. His long curved bill is also black, but his legs are bright red. The female has red legs but she’s mostly greeny-yellow.

The North American tanagers are actually more closely related to the cardinal than to other tanagers, and are placed in the family Cardinalidae. The family is named after the northern cardinal, which is common throughout most of the United States and parts of Mexico. The male is bright red with black around his bill, while the female is more of a rosy brown color. Both have red bills and tufted crests. In North America, the cardinal appears on a lot of Christmas cards because its bright red plumage against a snowy background is so cheerful in winter.

This is what a northern cardinal sounds like:

[bird sound]

Alexandra also suggested the blue grosbeak, while Joel suggested the yellow grosbeak. Both are also members of the family Cardinalidae. The blue grosbeak lives in much of the United States in summer and spends the winter in Mexico and Central America. The male is blue with black and rufous markings and a silvery-gray beak, while the female is rufous-brown and gray. The yellow grosbeak lives along the Pacific slope of Mexico and may be the same as the golden grosbeak that lives in western South America, or a very close relation. Scientists aren’t sure yet. The male is a bright golden yellow with black and white wings and a black bill, while females are a less conspicuous green-yellow. The yellow grosbeak is larger than the blue but they’re both pretty big and robust. They eat insects and lots of other small animals like snails and spiders, along with fruit and seeds. Sometimes a yellow grosbeak will show up farther north, in the United States, and birdwatchers lose their minds with excitement.

This is what a yellow grosbeak sounds like:

[bird sound]

Joel also suggested the purple martin, a type of swallow that’s common throughout the Americas. It’s not purple but it is a dark blue-black color with iridescence that reflects light. This makes the bird look anywhere from dark purple to blue depending on the angle of the light. The male is much darker than the female, who is more gray-blue in color. It spends the summer in North America, raising babies and eating lots of insects, then migrates to South America to spend the winter.

This is what a purple martin sounds like:

[bird sound]

Another Joel suggestion is the dusky thrush, which is another passerine that migrates a long distance. It spends the summer in Siberia and nearby areas to nest, then flies south to spend the winter in southern China, Japan, India, Vietnam, Korea, and other nearby areas. It’s mostly brown on its back and white underneath with lots of speckles, and a light stripe over its eye. Males and females look very similar. It eats insects, spiders, worms, seeds, and berries and spends a lot of its time on the ground. Every so often a dusky thrush will get lost during migration and end up in western Europe or Alaska, and again, birdwatchers in those areas go nuts trying to catch a glimpse of it.

This is what a dusky thrush sounds like:

[bird sound]

Let’s finish this episode with another of Joel’s suggestions, the European rose chafer. You may be wondering what kind of bird this is, and that is exactly what I was wondering. It sounds very pretty! Then I looked it up, and it’s not a bird at all, it’s a type of beetle!

The rose chafer is a big metallic-green beetle related to scarabs that grows up to 20 mm long. It’s common in Europe and some parts of southeast Asia, and is often found on rose bushes in summer. It eats flowers, including the petals, nectar, and pollen, and really likes roses.

The female rose chafer lays her eggs in the ground and the larvae eat decaying vegetation. There’s also a related beetle called the rose chafer that lives in parts of North America, but it’s sort of a muddy tan color, and while it likes to eat roses and other flowers, it also likes to eat fruit like peaches and grapes. Its larvae eat roots and can damage plants.

Since the European rose chafer is such attractive beetle, with an iridescent bronze shimmer to its emerald-green carapace, you’d think people who grow roses would like to have them on their rose bushes, but this isn’t actually the case. I guess people who grow roses want to see the roses without them being all chewed up by beetles. To bring it back to birds, birds don’t eat the rose chafer because the beetle contains toxins that make it taste awful. But they’re still really pretty.

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 425 Rabbits!

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Thanks to Alyx and Richard from NC for their suggestions this week! Let’s learn about rabbits!

Further reading:

Why your pet rabbit is more docile than its wild relative

FOUND: Small enigmatic rabbit with black tail lost to science for more than 120 years rediscovered hopping around mountain range in Mexico

The Omiltemi cottontail rabbit, as caught on a camera trap [photo taken from second article linked above]:

Show transcript:

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

This week we’re going to talk about bunnies, and also learn about how a wild animal differs from its domesticated counterpart. Thanks to Alyx for suggesting this excellent topic. Thanks also to Richard from NC who alerted me to a rediscovered rabbit we’ll discuss too.

Thanks for all the well wishes in the last few weeks about my surgery. It went just fine and all I have now is a cool-looking new scar, although I was seriously hoarse for about a week. It’s pretty weather here in East Tennessee and officially it’s spring in the northern hemisphere, so let’s talk about some springtime bunnies!

Collectively rabbits and hares are called leporids after their family, Leporidae. Leporids are famous for hopping instead of walking, and they’re able to do so because their hind legs are longer than their front legs and have specialized ankle joints. Ancestors of leporids developed this ankle as much as 53 million years ago, but their legs were much shorter so they probably ran instead of hopped. Hares have longer legs than rabbits and can run faster as a result, but both rabbits and hares are known for their ability to bound at high speeds. When a rabbit or hare runs, it pushes off from the ground with the tips of its long hind toes, and its toes are connected with webbed skin so they can’t spread apart. If the toes did spread apart, they would be more likely to get injured. Rabbits and hares also don’t have paw pads like dogs and cats do. The bottom of its foot is covered with dense, coarse fur that protects the toes from injury. Its long claws help it get a good purchase on the ground so its feet won’t slip.

Leporids eat plants, including grass, weeds, twigs, and bark. Animals that eat grass and other tough plants have specialized digestive systems so they can extract as many nutrients from the plants as possible. Many animals swallow the plants, digest them for a while, then bring up cuds of plants and water to chew more thoroughly. Rabbits and hares don’t chew their cud in that way, but they do have a system that allows them to twice-digest the plants they eat.

After a leporid eats some plants, the plant pieces go into the stomach, naturally, and then travel into the first part of the large intestine, called the cecum. The cecum separates the softer parts of the plants from the harder, less digestible parts. The hard parts are compressed into hard pellets that the rabbit poops out. But the soft parts of the plants, which are most nutritious, develop into softer pellets. These are called cecotropes, and as soon as the rabbit poops out the cecotropes, it immediately eats them again. This allows the digestive system to get a second round to extract more nutrients from the plants.

Hares aren’t domesticated, but rabbits have probably been domesticated many times in different places over the last several thousand years, first for food and fur, and then as pets. The domesticated rabbit we have today is descended from the European rabbit, also called the cony. If other species of rabbit were ever domesticated, we don’t have record of it. The rabbit has also been introduced into the wild in places it has no business to be, like Australia, where it’s an invasive species. You know where else the European rabbit has been introduced? The British Isles. It’s native to mainland Europe, not England, Scotland, Ireland, Wales, and smaller islands nearby. Historians think the rabbit was introduced to England soon after the year 1066, but it got really common a few hundred years later.

We discussed domestication way back in episode 106, mostly in relation to dogs. An interesting thing happens with domestication. Certain physical traits come along with the behavioral traits of reduced aggression and willingness to treat humans as surrogate parents. In the case of dogs, these often include a puppy-like appearance, including floppy ears, curled tail, smaller adult size, and a rounder head with smaller jaws. White patches of fur start to show up too.

This is true in rabbits as well as dogs. Because humans wanted to breed rabbits that weren’t scared of people, domesticated rabbits are less anxious and aggressive in general than their wild counterparts. When traits like white patches, lop ears, and a more rounded face appeared in the domesticated population, people would keep those rabbits to breed because they’re extra cute, which has led to over three hundred different breeds recognized today by rabbit enthusiasts.

Because domesticated rabbits are calmer and more trusting than wild rabbits, they can’t survive long in the wild. A domesticated rabbit doesn’t know how to escape from predators or avoid cars, and it’s not used to cold weather. If you decide to adopt a bunny, make sure you do research ahead of time to know what to expect, and as with most animals it’s best to adopt two so they won’t be lonely. Rabbits are social animals and need a rabbit friend. There are even pet rescues that specialize in rabbits who need homes.

We talked about giant rabbits in episode 115, and the tiny volcano rabbit in episode 356, so let’s finish this episode with a medium-sized rabbit called the Omiltemi cottontail. Cottontail rabbits are native to the Americas and most have fluffy white fur on the underside of their tails. The Omiltemi cottontail doesn’t have any white fur at all, and is reddish-brown and black in color with some lighter gray on its face. It’s large for a wild rabbit, about 18 inches long, or 45 cm, although it’s actually smaller than other rabbits that live in the area. It lives only in Mexico, specifically in a single part of the Sierra Madre del Sur mountain range, in what is now the Omiltemi Ecological State Park.

It was first described in 1904 and then reportedly wasn’t seen again, although the local people knew all about it. Even though it lives in a protected area, poaching is still a big problem. When an expedition to find the rabbit got underway in 2019, local hunters provided pelts to the scientists when they asked about the rabbit, since they didn’t know they weren’t supposed to kill the local rabbits. They certainly didn’t know they had an incredibly rare species of rabbit living in their back yards.

The team used camera traps, drone surveys, and the knowledge of local people to find and identify the Omiltemi cottontail. It turns out that the rabbit is mostly nocturnal and prefers higher elevations, which made it harder to find. We still don’t know how many there are left, but now that scientists are certain that it’s not extinct, it can be better protected.

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 424 Old-Timey Giant Snakes

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Show transcript:

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

Recently I read about a giant snake supposedly seen in Tennessee in 1908. The story seemed a little suspicious so I dug into it, and it got a lot more complicated than I expected.

On July 25, 1908, the St. Louis (Missouri) Globe-Democrat ran an article about a giant snake in Loudon, Tennessee. Loudon is a town half an hour’s drive away from Knoxville in East Tennessee, although it took longer to get there from Knoxville in 1908. According to the article, the snake was “at least twenty-five feet in length, eight inches in diameter and twenty-four inches in circumference.”

The longest snake ever reliably measured is a reticulated python named Medusa, who was measured as 25 feet 2 inches long in 2011, or 7.67 meters. Medusa holds the world record for the longest snake in captivity. Reticulated pythons are constrictors, which are non-venomous snakes who kill their prey by squeezing them until blood flow is shut off to the organs, causing cardiac arrest and death. As a result, they’re incredibly strong snakes. The reticulated python is native to southern Asia and not likely to be found running loose in East Tennessee even today, and certainly not in 1908.

The famous Boa constrictor and other snakes in the genus Boa are all native to Central and South America, while the closely related anaconda is from tropical South America. These snakes are also constrictors.

The anaconda is rumored to grow over 30 feet long, or 9 meters, although the longest specimen ever reliably measured was 17 feet long, or 5.2 meters. Since snake skin is stretchy, though, preserved skins of huge size are often provided as proof of snakes much longer than the known maximum. While the anaconda isn’t as long as the reticulated python, it’s much bulkier, so a 25-foot anaconda would be much heavier and larger around than a 25-foot reticulated python.

The 1908 article claims that the snake “has been seen off and on for the last twenty-eight years, but not until this summer has it caused any serious alarm.” I don’t know about you, but even as someone who likes animals and thinks snakes are neat, if I saw a 25-foot snake I would be a little bit alarmed even if it wasn’t doing anything. The article then describes how the snake had knocked down a fence while climbing over it and that it had taken a lamb. One man even managed to shoot the snake, although only with “small shot,” and the article claims that the snake, “in a frenzy from the pain, tore up saplings in getting away.”

The article finishes by reporting that women and children were barricaded in their homes while men organized a posse to hunt down the giant snake, which was rumored to live in a cave overlooking the river.

The same article ran in various newspapers around the country for months, but there was no follow-up to let readers know if the snake had been found. But the story didn’t appear in any Tennessee newspapers.

The only 1908 article about a giant snake in Tennessee that appears in a Tennessee newspaper is from August 21. The Chattanooga, Tennessee Daily Times reported that a blacksnake “fully six feet long and two inches in diameter” had been spotted eating young pigeons above the Birmingham railway station. A police officer shot and killed it, but its body couldn’t be recovered from the steep hillside above the tunnel.

“Blacksnake” is a term used for two snakes that are common throughout the southern United States: the eastern black kingsnake and the North American racer. Both are black in color and can grow more than 6 feet long, or 1.8 meters. Both are non-venomous and eat small animals like mice, frogs, and lizards, while the kingsnake also sometimes eats other snakes.

The longest snake found in Tennessee, which also lives throughout much of eastern North America, is the gray ratsnake, which is frequently 6 feet long and sometimes longer. One unverified report of a captive snake 8 feet 10 inches long, or almost 2.5 meters, comes from Tennessee. It’s a mixture of dark and light gray with a lighter belly. It’s non-venomous and is actually a constrictor, although it’s not dangerous to humans. If it feels threatened, it will sometimes pretend to strike and rattle the tip of its tail against dead leaves or whatever else might be underneath it, which produces a buzzing sound that mimics a rattlesnake’s rattle. You’re not fooling anyone, gray ratsnake.

The eastern racer will also vibrate its tail against leaves to imitate a rattlesnake’s rattle, but the eastern racer is such a fast-moving snake that it doesn’t usually need to convince potential predators it’s dangerous. It just runs away. Despite its name of Coluber constrictor, it’s not actually a constrictor, although it will pin an animal to the ground with its body until it can swallow it whole. It and the gray ratsnake can both climb trees and will eat bird eggs and young birds when they find them.

There is another article about a giant snake in a Tennessee newspaper from 1908. The Chattanooga Star reported on August 20 that a 12-foot, or 3.6 meter, rattlesnake was attacked by a boar when it tried to enter a hog pen. The farmer managed to shoot the snake, which had 29 rattles. The snake was referred to as “Big Jim” in the area. But that story was supposed to have happened in Sullivan, Indiana, not in Tennessee.

But Indiana newspapers don’t run this account. A July 22, 1908 article in the Indianapolis News reports that a rattlesnake with 26 rattles was killed in Nashville, Indiana, but that snake was not quite six feet long, or 1.8 meters.

The “Big Jim” account does appear in one Indiana newspaper, the Hamilton County Times from August 21, 1908. But that article is headlined “Some Hoosier ‘Nature Fakes’” and says Big Jim was first spotted in the neighboring state of Illinois but had been discovered attacking a farmer’s chickens in Sullivan County, Indiana. This must be the same as Sullivan, Indiana reported in the Tennessee paper. But Big Jim was only ten feet long in the Indiana story, or 3 meters, and wasn’t killed. The article says the local farmers were organizing to hunt it down, but then goes on to talk about some other stories of huge snakes and a giant fish. It seems clear that the Indiana article is meant to be amusing, not factual.

The largest rattlesnake species is the eastern diamondback rattler, and the largest one ever reliably measured was 7.8 feet long, or 2.4 meters. That’s big, but it’s not Big Jim big. The eastern diamondback also doesn’t live anywhere near Indiana or Illinois. It’s native to the southeastern United States, especially along the coast.

Newspaper reporters weren’t always scrupulous in the olden days, sometimes making up stories to fill space and entertain the reader. Stories of huge snakes are so common in old newspaper reports that the term “snake story” was once used interchangeably with “fish story” to indicate an animal of improbable size that was supposedly spotted or killed, but without any proof.

In 1935, the Statesville (North Carolina) Record and Landmark ran an article titled “Giant Snake Story Proves To Be Hoax.” No kidding! In this case, though, the story was about a snake skin 16 feet long, or nearly 5 meters, which was supposed to be from a rattlesnake killed in a local swamp. The article revealed that the two men who claimed to have shot the rattlesnake had later confessed the skin was from a python, and had been sent to one of the men by a relative in South America. At least that one was from a real snake.

Thanks for your support, and thanks for listening!

Episode 423: Pack Rats and Busy Mice

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Further reading:

Mouse filmed moving items in man’s shed in Bristol

The pack rat:

Show transcript:

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

This week I’m sharing a Patreon episode from last year because I have surgery scheduled. Don’t worry, it’s minor thyroid surgery and I’ll be fine, but my doctor said that a side effect might be hoarseness while I recover. Rather than risk sounding like an old frog, and to allow myself lots of time to rest afterwards, I’ve scheduled Patreon episodes for this week and next week.

At the beginning of this year, in early January 2024, you may have heard about a man in Wales who had an interesting visitor to his work shed. Rodney Holbrook is 75 years old and a retired postal worker, and at the end of 2023 he started noticing something weird. Things in his work shed kept being moved, and not in a way that suggested another person was getting in.

Initially Rodney noticed that some bird food had been moved into an old pair of shoes. This wasn’t just a one-time thing that would suggest an accident, like maybe Rodney had absent-mindedly decided to store the bird food in his shoes, or maybe it just fell there. The bird food kept ending up in the shoes.

Other things kept getting moved too. Small items that Rodney had left out while making and repairing things at his work bench kept getting put into a box, like tools and nuts and bolts. It happened almost every night.

Fortunately, Rodney is also a wildlife photographer, and he just happened to have a night vision camera. He set it up in the shed to find out what on earth was going on.

A mouse was going on, that’s what was going on. This actually wasn’t a huge surprise to Rodney, because years before, in 2019, a friend of his had had the same thing happen.

His friend was Steve Mckears who lived near Bristol, England. Steve kept crushed peanuts in a tub to use as bird food, but he started to notice other things mixed in with the peanuts. First it was just one screw, then it was lots more things that he’d left around his shed. He couldn’t figure out a solution, because he always locked his shed at night.

As Steve said at the time, “I was worried. I’m 72 and you hear of things going wrong with 72-year-old gentlemen in the mind.” Fortunately, Steve’s friend Rodney set up a camera and proved that there was nothing wrong with Steve’s mind or with the shed’s lock. It was just a mouse who was tidying up.

The question is why are these mice tidying up someone else’s shed? Don’t the mice have sheds of their own to clean up? It’s probable that the mice are actually living in the sheds and are wondering why some humans keep barging in every day and making a mess.

Rodents of all kinds do tend to tidy up as part of the foraging and nesting process. Sometimes that means moving debris so the animal can find important items more easily, sometimes it means bringing items back to its nest. House mice and rats will steal small items from humans to make nests, like socks and facecloths. Some rodents are attracted to shiny things and will stash them away or even bury them.

One animal, the pack rat, is so famous for storing items that we call a person who likes to collect things a pack rat. The pack rat lives throughout much of North and Central America and is related to mice and rats. It’s bigger than a mouse but smaller than most rats, and some species have furry tails like ground squirrels. It builds a den out of whatever materials are available where it lives, and its den is complex and usually well hidden. Desert species like to build under a cactus, while others live in cliffs or among rocks, in abandoned buildings or sometimes non-abandoned buildings, under bushes, in the tops of trees, or even in the entrances to caves. The den can be quite large and contains numerous rooms used for food storage, sleeping, and storing all the interesting things the pack rat finds while foraging.

A pack rat constructs a debris pile to hide its den, referred to as a midden. “Midden” is an old-fashioned word used to describe a place where household waste used to be thrown. Archaeologists love middens because you can learn a lot about people by the things they throw away, and other scientists love pack rat middens for the same reason. Some pack rat middens have been discovered preserved for 50,000 years, which has allowed scientists to learn a lot about what plants were growing in the area at the time. Since the middens also contain the pack rat’s fecal pellets, the scientists can also learn a lot about what the rat was eating, how big it was, and so forth.

Pack rats especially like shiny objects and will steal from people. In 2017 when historians were restoring an old home in Charleston, South Carolina dating back to 1808, they discovered several old pack rat middens in the walls of the kitchen. The middens contained buttons, marbles, sewing pins, and even some scraps of paper, including bits of newspaper with a readable date from November 1833. But some of the other bits of paper were torn from a writing primer, a book for people learning how to read or write. That’s not much of a surprise until you remember that this was the early 19th century, that the house was owned by a slave trader, and that the kitchen in particular would have been staffed by enslaved people, who were not supposed to learn how to read. Thanks to the pack rats, we know that at least one person was secretly learning how to read and write. I just hope the rats didn’t do too much damage to their book.

The pack rat is also sometimes called a trader rat, because it can only carry one thing at a time. If it’s carrying an acorn home and it chances upon a shiny gold ring, it will drop the acorn and carry the ring home. But you wanted an acorn, didn’t you, instead of that ring?

As for mice tidying up, we don’t really know why they do it, but it’s probably actually quite common. It just happens at night when people aren’t around, and in the morning they don’t know why all the nails have been moved into the box of nails, but hey, isn’t that handy? It reminds me of the stories of little house spirits called brownies, which were supposed to work at night cleaning and tidying. When the family woke up the next morning, the house or workshop was, ahem, squeaky clean, and all the family had to do was leave out a little cake or cream every night for the brownie.

Thanks for your support, and thanks for listening!

Episode 413: The Great American Interchange

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Thanks to Pranav for suggesting this week’s massive topic!

Further reading:

When did the Isthmus of Panama form between North and South America?

Florida fossil porcupine solves a prickly dilemma 10-million years in the making

Evidence for butchery of giant armadillo-like mammals in Argentina 21,000 years ago

Glyptodonts were big armored mammals:

The porcupine, our big pointy friend:

Show transcript:

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

This week, at long last, we’re going to learn about the great American interchange, also called the great American biotic interchange. Pranav suggested this topic ages ago, and I’ve been wanting to cover it ever since but never have gotten around to it until now. While this episode finishes off 2024 for us, it’s the start of a new series I have planned for 2025, where every so often we’ll learn about the animals of a particular place, either a modern country or a particular time in history for a whole continent.

These days, North and South America are linked by a narrow landmass generally referred to as Central America. At its narrowest point, Central America is only about 51 miles wide, or 82 km. That’s where the Panama Canal was built so that ships could get from the Atlantic Ocean to the Pacific and vice versa without having to go all around South America.

It wasn’t all that long ago, geologically speaking, that North and South America were completely separated, and they had been separated for millions of years. South America was part of the supercontinent Gondwana, while North America was part of the supercontinent Laurasia.

We’ve talked about continental drift before, which basically means that the land we know and love on the earth today moves very, very slowly over the years. The earth’s crust, whether it’s underwater or above water, is separated into what are called continental plates, or tectonic plates. You can think of them as gigantic pieces of a broken slab of rock, all of the pieces resting on a big pile of really dense jelly. The jelly in this case is molten rock that’s moving because of its own heat and the rotation of the earth and lots of other forces. Sometimes two pieces of the slab meet and crunch together, which forms mountains as the land is forced upward, while sometimes two pieces tear apart, which forms deep rift lakes and eventually oceans. All this movement happens incredibly slowly from a human’s point of view–like, your fingernails grow faster than most continental plates move. But even if a plate only moves 5 millimeters a year, after a million years it’s traveled 5 kilometers.

Anyway, the supercontinent Gondwana was made up of plates that are now South America, Africa, Australia, Antarctica, and a few others. You can see how the east coast of South America fits up against the west coast of Africa like two puzzle pieces. Gondwana actually formed around 800 million years ago, then became part of the even bigger supercontinent Pangaea, and when Pangaea broke apart around 200 million years ago, Gondwana and Laurasia were completely separate. North America was part of Laurasia. But Gondwana continued to break apart. Africa and Australia traveled far away from South America as molten lava filled the rift areas and helped push the plates apart, forming the South Atlantic Ocean. Antarctica settled onto the south pole and India traveled past Africa until it crashed into Eurasia. By about 30 million years ago, South America was a gigantic island.

It’s easy to think that all this happened just like taking puzzle pieces apart, but it was an incredibly long, complicated process that we don’t fully understand. To explain just how complicated it is, let’s talk for a moment about marsupials.

Marsupials are mammals that are born very early and finish developing outside of the mother’s womb, usually in a special pouch. Kangaroos, wallabies, koalas, wombats, and Tasmanian devils are all marsupials, and all from Australia. But marsupials didn’t originate in Australia and are still present in other parts of the world.

The oldest known marsupial appears in North America about 65 million years ago, which was part of the other supercontinent on Earth at the same time as Gondwana, called Laurasia. About the time marsupials were spreading out across Laurasia, from North America all the way to China, Laurasia and Gondwana were connected for a while along the northern edge of South America. Animals were able to cross from Laurasia to Gondwana before the two supercontinents split apart again. Marsupials spread from Laurasia and across Gondwana before the continent of Australia separated about 50 million years ago. Marsupials did so well in Australia that researchers think that before Australia was fully separated from Gondwana, marsupials actually started spreading back out of Australia and into Gondwana again.

While marsupials were doing extremely well in Australia, in South America, birds were the dominant vertebrate for a long time. We talked about terror birds in episode 202. Phorusrhacidae is the name for a family of flightless birds that lived from about 62 million years ago to a little under 2 million years ago. They were carnivores and various species ranged in size from about 3 feet tall to 10 feet tall, or 1 to 3 meters, and had long, strong legs that made them fast runners. The terror bird also had a long, strong neck, a sharp hooked beak, and sharp talons on its toes.

Other birds in North America were likewise huge, but could fly. Those were the teratorns, which are related to modern New World vultures. Since they had huge wingspans and could fly long distances easily, they could just fly between North and South America if they wanted to, so teratorns were found on both continents starting around 25 million years ago. They only went extinct around 10,000 years ago. The largest species known, Argentavis magnificens, lived in South America around six million years ago. It’s estimated to have a wingspan of at least 20 feet, or 6 meters, and possibly as much as 26 feet, or 8 meters. That’s the size of a small aircraft.

In addition to giant predator birds, South America had crocodilians that could grow over 30 feet long, or 9 meters, and possibly as much as 40 feet long, or 12 meters. And, of course, it had ancestral forms of animals we’re familiar with today, like sloths, anteaters, armadillos, opossums, monkeys, capybaras, and lots more. Some of these were incredibly large too, like the giant ground sloth that was as big as an African elephant and the glyptodon that was related to modern armadillos. Glyptodon had a huge bony carapace and rings of bony plates on the end of its thick tail that made it into a club-like weapon, and it was the size of a car. Both the giant ground sloths and the glyptodonts were plant-eaters, as were the notoungulates.

The notoungulates are an extinct order of hoofed animals that lived throughout South America. They were probably most closely related to rhinoceroses, horses, and other odd-toed ungulates, but they’re completely extinct with no living descendants. Some were tiny and actually looked and probably acted more like rabbits than horses, while others were massive. We talked about trigodon in episode 387, and it and many of its close relations in the family Toxodontidae were the size and build of a modern rhinoceros. Trigodon even had a small horn on its forehead. A closely related group, Litopterna, is also a completely extinct order of ungulates, which were mostly smaller and more deer-like than the notoungulates.

The Pleistocene is also called the ice age, but it’s more accurate to say that it was a series of ice ages with long periods of warmer weather in between–tens of thousands of years of warmer climate, then a colder cycle that lasted tens of thousands more years. When the glaciers were at their maximum, with ice sheets covering some parts of the world over a mile thick, or a kilometer and a half, sea levels were considerably lower because so much of the world’s water was frozen solid. That exposed more land that would ordinarily be partially or completely underwater, and it also led to a dryer climate overall. At the same time, volcanic activity in the ocean separating what is now North and South America had been building up volcanic islands for millions of years. All these factors and more combined to form the Isthmus of Panama, also called Central America, that is basically a land bridge connecting the two continents.

This started around 5 million years ago and the isthmus was fully formed by about 3 million years ago, or at least that’s the most accepted theory right now. A 2016 study suggested that the land bridge started forming far earlier than that, possibly as early as 23 million years ago, possibly 6 to 15 million years. Studies are ongoing to learn more about the timeline.

What we do know is that once the land bridge opened up, animals started migrating into this new area. Animals from North America migrated south, and animals from South America migrated north. It didn’t happen all at once, of course. It was a slow process as various animal populations expanded into Central America over generations. Some animals had trouble with the climate or couldn’t find the right foods, while others did really well and expanded rapidly.

The ancestors of some animals that made it to North America and are still around include the Virginia opossum, the armadillo, and the porcupine. Meanwhile, the ancestors of llamas, horses, tapirs, deer, canids, felids, coatis, and bears traveled to South America and are still there, along with many smaller animals like rodents. Many other animals migrated, survived for a while, but later went extinct. This included a type of elephant called the gomphothere and saber-toothed cats that migrated south, while ground sloths, terror birds, glyptodonts, capybaras, and even a type of notoungulate migrated north.

You may notice that more animals that migrated south survived into modern times. South America was much warmer overall than North America, and most animals that traveled north had trouble adapting to a colder climate and competing with animals that were already well-adapted to the cold. Animals traveling south encountered warmer climates early, and if they were able to tolerate hot weather they didn’t have to worry about any climactic shocks on the rest of their journey south. As a result, North American animals were able to establish themselves in larger numbers, which helped them adapt even faster since more babies were being born and surviving.

One South America to North America success story is the porcupine. Porcupines are rodents, and there are two groups, referred to as old world and new world porcupines. Those are not great terms but that’s what we have right now. The old world porcupines are found in parts of Africa, Asia, and Italy, although they were once more widespread in Europe, while new world porcupines are found in parts of North and South America. Old world porcupines live exclusively on the ground and are larger overall than new world ones, which spend a lot of time in trees. Surprisingly, the two groups are only distantly related. They evolved spines separately. They’re also only very distantly related to hedgehogs.

The one thing everyone knows about the porcupine is that it has quills, long sharp spines that make hedgehog spines look positively modest. Porcupine quills are dangerous. They’re modified hairs, and actual hair grows in between the quills, but they’re covered in strong keratin plates and are extremely sharp. They also come out easily and regrow all the time. A porcupine can hold its spines down flat so it won’t hurt another porcupine, which is what they do when they mate.

Only one species of porcupine lives in North America, called the North American porcupine. It lives throughout much of the northern and western part of the continent, from way up in the far north of Canada down to central Mexico, although it doesn’t live in most of the southeast. We don’t know if the North American porcupine developed after South American porcupines migrated north, or if it developed much earlier, around 10 million years ago. Porcupine experts have been arguing about this for years, because there aren’t very many porcupine fossils to study.

Then a nearly complete fossil porcupine was discovered in Florida. It was such a big deal that the scientific team that discovered it decided to create an entire college course for paleontology students to help study the specimen. The resulting study was published in May of 2024, and the results suggest that the North American porcupine evolved a lot longer ago than the Isthmus of Panama formed.

The North American porcupine had to change a lot to withstand the intense cold when its ancestors were tropical animals. The North American porcupine is very different from its South American cousins. It spends less time in trees and doesn’t have a prehensile tail, it eats a lot of bark instead of mostly leaves, and it has thick insulating fur between its quills. The fossilized specimen discovered in Florida still had a prehensile tail and didn’t have the strong jaw it needed to gnaw bark off trees, but it already showed a lot of adaptations that are seen in the North American porcupine but not in South American species.

Ultimately, of course, a lot of large animals went extinct around 12,000 to 10,000 years ago, the end of the Pleistocene. Animals like mammoths that were well-adapted to cold died out as the climate warmed, and so did their predators, like dire wolves and the American lion. The notoungulates and other megaherbivores in South America went extinct too.

One animal that I haven’t mentioned yet that migrated south successfully was Homo sapiens. Maybe you’ve heard of them. Until very recently, the accepted time frame for humans migrating into South America was about 16,000 years ago, although not everyone agreed. But in July of 2024, a new study pushed that date back to 21,000 years ago.

The study examined glyptodont fossils found in what is now Argentina. The fossils were found on the banks of a river and were determined to show butchering marks from stone tools. The bones were dated to almost 21,000 years ago, which means that humans probably moved into South America a lot earlier than that. It takes time to travel from Central America down to Argentina.

One detail most people don’t know about when it comes to the Great American Interchange is how marine animals were affected. It was exactly opposite for them. Instead of a new land to explore, which caused very different animals to encounter each other for the first time, the Isthmus of Panama cut populations of marine animals from each other. They’ve been evolving separately ever since. So I guess whether a land bridge is bad or good depends on your point of view.

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 412: Whales and Dolphins

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Thanks to Elizabeth, Alexandra, Kimberly, Ezra, Eilee, Leon, and Simon for their suggestions this week!

Further reading:

New population of blue whales discovered in the western Indian Ocean

An Endangered Dolphin Finds an Unlikely Savior–Fisherfolk

The humpback whale:

The gigantic blue whale:

The tiny vaquita:

The Indus river dolphin:

The false killer whale:

Show transcript:

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

This week we’re going to have a big episode about various dolphins and whales! We’ve had lots of requests for these animals lately, so let’s talk about a bunch of them. Thanks to Elizabeth, Alexandra, Kimberly, Ezra, Eilee, Leon, and Simon for their suggestions.

We’ll start with a quick overview about dolphins, porpoises, and whales, which are called cetaceans. All cetaceans alive today are carnivorous, meaning they eat other animals instead of plants. This includes the big baleen whales that filter feed, even though the animals they eat are tiny. Cetaceans are mammals that are fully aquatic, meaning they spend their entire lives in the water, and they have adaptations to life in the water that are simply astounding.

All cetaceans alive today belong to either the baleen whale group, which filter feed, or the toothed whale group, which includes dolphins and porpoises. The two groups started evolving separately about 34 million years ago and are actually very different. Toothed whales are the ones that echolocate, while baleen whales are the ones that have extremely loud, often beautiful songs that they use to communicate with each other over long distances. It’s possible that baleen whales also use a limited type of echolocation to navigate, but we don’t know for sure. There’s still a lot we don’t know about cetaceans.

Now let’s talk about some specific whales. Ezra wanted to learn more about humpback and blue whales, so we’ll start with those. Both are baleen whales, specifically rorquals. Rorquals are long, slender whales with throat pleats that allow them to expand their mouths when they gulp water in. After the whale fills its mouth with water, it closes its jaws, pushing its enormous tongue up, and forces all that water out through the baleen. Any tiny animals like krill, copepods, small squid, small fish, and so on, get trapped in the baleen. It can then swallow all that food and open its mouth to do it again. The humpback mostly eats tiny crustaceans called krill, and little fish.

The humpback grows up to 56 feet long, or 17 meters, with females being a little larger than males on average. It’s mostly black in color, with mottled white or gray markings underneath and on its flippers. Its flippers are long and narrow, which allows it to make sharp turns.

The humpback is closely related to the blue whale, which is the largest animal ever known to have lived. It can grow up to 98 feet long, or 30 meters, and it’s probable that individuals can grow even longer. It can weigh around 200 tons, and by comparison a really big male African elephant can weigh as much as 7 tons. Estimates of the weight of various of the largest sauropod dinosaurs, the largest land animal ever known to have lived, is only about 80 tons. So the blue whale is extremely large.

The blue whale only eats krill and lots of it. To give you an example of how much water it can engulf in its enormous mouth in order to get enough krill to keep its massive body going, this is how the blue whale feeds. When it finds an area with a lot of krill floating around, it swims fast toward the krill and opens its giant mouth extremely wide. When its mouth is completely full, its weight—body and water together—has more than doubled. Its mouth can hold up to 220 tons of water. Since the whale is in the water, it doesn’t feel the weight of the water in its mouth.

Blue whales live throughout the world’s oceans, but a few years ago scientists analyzing recordings of whale song from the western Indian Ocean noticed a song they didn’t recognize. It was definitely a blue whale song, but one that had never been documented before. Not long after, one of the same scientists was helping analyze humpback whale recordings off the coast of Oman and recognized the same unusual blue whale song.

After the finding was announced, other scientists checked their recordings from the Indian Ocean and a few realized they had the mystery blue whale song too. The recordings come from a population of blue whales that hadn’t been documented before, and which may belong to a new subspecies of blue whale.

Elizabeth, Alexandra, and Leon all wanted to learn about dolphins. Kimberly also specifically wanted to learn about the Indus River dolphin and Leon about the vaquita porpoise. Dolphins and porpoises are considered toothed whales, but they’re also relatively small and can swim very fast. Orcas are actually dolphins even though they’re often called killer whales.

Even a small cetacean is really big, but the exception is the vaquita. It’s the smallest cetacean alive today, not even five feet long, or 1.5 meters. It lives only in the upper Gulf of California and is gray above and white underneath, with black patches on its face.

The vaquita spends very little time at the surface of the water, so it’s hard to spot and not a lot is known about it. It mostly lives in shallow water and it especially likes lagoons with murky water, since that’s where it can find lots of the small animals it eats, including small fish, squid, and crustaceans.

The vaquita is critically endangered, mostly because it often gets trapped in illegal gillnets and drowns.  There may be as few as ten individuals left alive. Attempts at keeping the vaquita in captivity have failed, but it’s strictly protected by both the United States and Mexico. Some scientists worry that even though vaquita females are still having healthy calves, there are so few of the animals left that they might not recover and are functionally extinct. But only time will tell, so the best thing everyone can do is what we’re already doing, keeping the vaquita and its habitat as safe as possible.

Another small cetacean is the Indus River dolphin, which grows up to 8 and a half feet long, or 2.6 meters. As you can probably guess from its name, it actually lives in fresh water instead of the ocean, specifically in rivers in Pakistan and India. It’s pinkish-brown in color and has a long rostrum, or beak-like nose, which turns up slightly at the end and is filled with sharp teeth that it uses to catch fish and other small animals. Because the rivers where it lives are murky, the dolphin doesn’t have very good eyesight. It probably can’t see anything except light and dark with its tiny eyes, but it can sense its surroundings just fine with echolocation.

Like most cetaceans, the Indus River dolphin is endangered, but it’s doing a lot better these days than it was just a few decades ago. In the 1970s only about 150 of the little dolphins were left alive, and by 2001 there were a little over 600. Today there are around 2,000. Habitat loss, pollution, and accidental drowning in fishing nets are still ongoing problems, but these days the fishing families that live along the river are helping it whenever they can. The fishers rescue dolphins who get stranded in shallow water and irrigation canals, and the government encourages this by paying the fishers a small amount for their help. Since this part of the country is very poor, a little bit of extra money can mean a big difference for the families, and of course their help means a lot to the dolphins too.

One interesting thing is that the Indus River dolphin often swims on its side. That is, it just tips over sideways and swims around as though that’s the most normal thing in the world. Scientists think this helps it navigate shallow water. And the Indus River dolphin isn’t very closely related to other dolphins and whales.

Quite a while ago now, Simon brought the false killer whale to my attention. In 1846 a British paleontologist published a book about British fossils, and one of the entries was a description of a dolphin. The description was based on a partially fossilized skull discovered three years before and dated to 126,000 years ago. It was referred to as the false killer whale because its skull resembled that of a modern orca. Scientists thought it was the ancestor of the orca and that it was extinct.

Or maybe not, because in 1861, a dead but very recently alive one washed up on the coast of Denmark.

The false killer whale is dark gray and grows up to 20 feet long, or 6 meters. It mostly eats squid and fish, including sharks. It’s not that closely related to the orca and actually looks more like a pilot whale. It will sometimes hang out with dolphins, including occasionally hybridizing with bottlenose dolphins, but then again sometimes it will eat dolphins. Watch out, dolphins.

Finally, Eilee wanted to learn about little-known whales, and that definitely means beaked whales. There are 24 known species of beaked whale, but there may still be species unknown to science. We know very little about most of the known species, because they live in remote parts of the ocean. They prefer deep water and are extremely deep divers, with the Cuvier’s beaked whale recorded as diving as deep as 1.8 miles, or almost 3 km, and staying underwater without a breath for 222 minutes. That’s approximately 220 minutes longer than a human can hold their breath.

Let’s finish with Sato’s beaked whale, which was only described in 2019. It’s black with a chunky body and small flippers and dorsal fin. It also has a short beak. It lives in the north Pacific Ocean and was thought to be a darker population of Baird’s beaked whale, which is gray, but genetic studies and a careful examination of dead beached individuals proved that it was a completely different species. It grows up to 23 feet long, or 7 meters, but since no female specimens have ever been found, we don’t know if the female is larger or smaller than the male.

We basically know nothing about this whale except that it exists, and the fact that it is alive and swimming around in the ocean right now, along with other whales, is an amazing, wonderful thing.

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 406: Some Turtles and a Friend

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Thanks to Riley and Dean, Elizabeth, and Leo for their suggestions this week!

Further reading:

Groundbreaking study reveals extensive leatherback turtle activity along U.S. coastline

A bearded dragon:

The tiny bog turtle:

The massive leatherback sea turtle:

The beautiful hawksbill turtle [photo by U.S. Fish and Wildlife Service]:

Show transcript:

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

This week we’re going to learn about some reptiles suggested by four different listeners: Riley and Dean, Elizabeth, and Leo.

We’ll start with the brothers Riley and Dean. Dean wants to learn more about the bearded dragon, and that may have something to do with a certain pet bearded dragon named Kippley.

“Bearded dragon” is the name given to any of eight species of lizard in the genus Pogona, also referred to as beardies. They’re native to Australia and eat plants and small animals like worms and insects. They can grow about two feet long, or 60 cm, including the tail, but some species are half that length. Females are a little smaller than males on average.

The bearded dragon gets its name because its throat is covered with pointy scales that most of the time aren’t very noticeable, but if the lizard is upset or just wants to impress another bearded dragon, it will suck air into its lungs so that its skin tightens and the spiky scales under its throat and on the rest of its body stick out. They’re not very sharp but they look impressive. Since the bearded dragon can also change color to some degree the same way a chameleon can, when it inflates its throat to show off its beard, the beard will often darken in color to be more noticeable. Both males and females have this pointy “beard.”

Bearded dragons that are sold as pets these days are more varied and brighter in color than their wild counterparts, although wild beardies can be brown, reddish-brown, yellow, orange, and even white. Australia made it illegal to catch and sell bearded dragons as pets in the late 20th century, but there were already lots of them outside of Australia by then. Pet bearded dragons are mainly descended from lizards exported during the 1970s, which means they’re quite domesticated these days and make good pets.

Like some other reptiles and amphibians, the bearded dragon has a third eye in the middle of its forehead. If you have a pet beardie and are about to say, “no way, there is definitely not a third eye anywhere, I would have noticed,” the eye doesn’t look like an eye. It’s tiny and is basically just a photoreceptor that can sense light and dark. Technically it’s called a parietal eye and researchers think it helps with thermoregulation.

Next, Riley wants to learn about turtles, AKA turbles, and especially wants everyone to know the difference between a tortoise and a turtle. It turns out that while many turtles are just fine living on land, they’re often more adapted to life in the water. Turtles have a more streamlined shell and often flipper-like legs or webbed toes. Tortoises only live on land and as a result they have shells that are more dome-shaped, and they have large, strong legs that resemble those of a tiny elephant.

You can’t always go by an animal’s common name to determine if it’s a tortoise or a turtle, but it’s also not always clear whether an animal is a tortoise or a turtle at first glance. Take the eastern box turtle, for instance, which is common in the eastern United States. It has a domed carapace, or shell, but it’s still a turtle, not a tortoise. And, I’m happy to say, it can swim quite well. This is a relief to find out because when I was about six years old, my mom visited someone who had kids a little older than me. I didn’t know them but they were nice and showed me the swampy area near their house. At one point one of the older boys found a box turtle, took it over to a little bridge over a pond, and dropped it in the water. I screamed, and he was absolutely shocked. He said he thought box turtles belonged in the water and he was helping it, but I thought they couldn’t swim and he’d just killed the poor turtle. I have continued to think he’d killed the poor turtle until just now, when I learned they can swim, and I can’t even tell you how relieved I am. Anyway, eastern box turtles have a domed shell, yes, and stumpy club-like front legs, but their hind legs are less like elephant legs than regular turtle legs. Since box turtles can live to be 100 years old, it’s possible that that one is alive and well even now.

Riley also wants everyone to know not to take a turtle from the woods, which is a very good rule to live by. In fact, it’s important not to take any wild animals from the woods no matter how cute they are. To continue our example, eastern box turtles have small territories that they defend from other box turtles. If you take the turtle out of its territory even for just a few days, when you return it to the woods, another turtle may have already taken over and will chase it away. Turtles don’t travel very fast and are vulnerable to being hit by cars and eaten by lots of different predators, so without a safe territory where it can hide and find food, it can die very quickly.

One of the turtles Leo suggested we learn about was the bog turtle. It’s the smallest turtle in North America, with a carapace barely four inches long, or 10 cm. It lives in a few parts of the eastern United States, and likes marshy areas with slightly acidic water. It spends a lot of time in the water, but also plenty of time on land. It eats worms, slugs, snails, water plants, berries, insects, and even small frogs when it can catch them.

The bog turtle is so small that pretty much anything big enough to swallow it will eat it. Its main defense is to bury itself in soft mud and hide. It’s almost completely black or dark gray in color, but it does have a bright orange spot on each side of its neck.

The bog turtle is critically endangered due to habitat loss, pollution, and poaching for the illegal pet trade. Conservationists are working to improve its habitat, and in the meantime some zoos and aquariums are helping with a captive breeding program. Since a bog turtle isn’t old enough to lay eggs until it’s at least 8 years old, the species as a whole reproduces slowly.

Leo also suggested hawksbill and leatherback turtles, and Elizabeth wants to learn about sea turtles in general. We talked about sea turtles way back in episode 75, so it’s definitely time to revisit the topic.

Seven species of sea turtle are alive today, and you can tell they’re turtles and not tortoises because they have streamlined shells and flippers instead of feet. They migrate long distances to lay eggs, thousands of miles for some species and populations, and usually return to the same beach where they were hatched. Female sea turtles come ashore to lay their eggs in sand, but the males of most species never come ashore. The exception is the green sea turtle, which sometimes comes ashore just to bask in the sun. Once the babies hatch, they head to the sea and take off, swimming far past the continental shelf where there are fewer predators. They live around rafts of floating seaweed call sargassum, which protects them and attracts the tiny prey they eat.

Six of the extant sea turtles are relatively small. Not small compared to regular turtles, small compared to the seventh living sea turtle, the leatherback. It’s much bigger than the others and not very closely related to them. It can grow some nine feet long, or 3 meters, and instead of having a hard shell like other sea turtles, its carapace is covered with tough, leathery skin studded with tiny osteoderms. Seven raised ridges on the carapace run from head to tail and make the turtle more stable in the water, a good thing because leatherbacks migrate thousands of miles every year. Not only is the leatherback the biggest and heaviest turtle alive today by far, it’s the heaviest living reptile that isn’t a crocodile. It has huge front flippers, is much more streamlined even than other sea turtles, and has a number of adaptations to life in the open ocean.

The leatherback lives throughout the world, from warm tropical oceans up into the Arctic Circle. It mostly eats jellyfish, so it goes where the jellyfish go, which is everywhere. It also eats other soft-bodied animals like squid. To help it swallow slippery, soft food when it doesn’t have the crushing plates that other sea turtles have, the leatherback’s throat is full of backwards-pointing spines. What goes down will not come back up, which is great when the turtle swallows a jellyfish, not so great when it swallows a plastic bag. It’s endangered due to pollution, accidental drowning when it gets caught in fishing nets, and habitat loss of its nesting beaches.

The hawksbill, or hawkbill sea turtle grows to a much more reasonable size, around three feet long, or 90 cm, and mostly lives around tropical reefs. It has a more pointed, hooked beak than other sea turtles, sort of like a hawk, which gives it its name. You might think it eats fish with a beak like that, but it mostly eats jellyfish and sea sponges. It especially likes the sea sponges, some of which are lethally toxic to most other animals. It also doesn’t have a problem eating even extremely stingy jellies and jelly-like animals like the Portuguese man-o-war. The hawkbill’s head is armored so the stings don’t bother it, although it does close its eyes while it chomps down on jellies. Its meat can be toxic due to the toxins it ingests. People used to kill hawksbill sea turtles for their multicolored shells, but these days it’s a protected species like all sea turtles.

The hawksbill is also biofluorescent! Researchers only found this out by accident in 2015, when a team studying biofluorescent animals in the Solomon Islands saw and filmed a hawksbill glowing like a UFO with neon green and red light. So you never know what other secrets sea turtles might be hiding.

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!