Episode 278: Gender Diverse Animals

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

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

Further reading:

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

How a microbe chooses among seven sexes

Facultative Parthenogenesis in California Condors

The sparrow with four sexes

Chinstrap penguins make good dads:

Laysan albatrosses make good moms:

Black swans make good dads:

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

New Mexico whiptail lizards are all females:

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

Clownfish change sex under some circumstances:

The white-throated sparrow essentially has four sexes:

You are awesome (photo by By Eric Rolph)!

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

[white-throated sparrow call]

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

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

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

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

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

Thanks for listening!

Episode 277: Rewilding Scotland

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

The Scottish (or Highland) wildcat:

The Eurasian lynx:

The Eurasian beaver (with babies!):

The white-tailed eagle:

Reindeer in Scotland:

The pine marten:

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Thanks for listening!

Episode 276: Hominins and Art

It’s Nicholas’s episode this week, and Nicholas wants to learn more about hominins, the ancestors and cousins of modern humans!

Happy birthday to Autumn! I hope you have a great birthday!

Further listening:

Humans Part One

Further reading:

Were Neanderthals the Earliest Cave Artists?

Neanderthals Built Mysterious Stone Circles

DNA reveals first look at enigmatic human relative

What does it mean to have Neanderthal or Denisovan DNA?

Hand and footprint art dates to mid-Ice Age

Risky food-finding strategy could be the key to human success

A stone circle in a cave was probably built by Neandertals:

A deer bone with carving on it probably made by Neandertals:

Some cave paintings probably made by Neandertals:

Show transcript:

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

This week is Nicholas’s episode! Nicholas wanted an updated episode about hominins, our ancient ancestors or species closely related to modern humans. The last time we talked about hominins was way back in episodes 25 and 26, so it’s definitely time to revisit the topic.

But first, a big birthday shout-out to Autumn! Happy birthday, Autumn, and I hope you have the best birthday so far!

If you haven’t listened to episode 25 in a while, or ever, I recommend you go back and give it a listen if you want background information about how humans evolved and our closest extinct relatives, Neandertals and Denisovans. I’ve transcribed that episode finally, so you can read the episode instead of listen to it if you prefer. There’s a link in the show notes.

Results of a study published in January 2022 in the journal Nature has finally dated the oldest known Homo sapiens remains found so far. The remains were found in Ethiopia in the 1960s but the volcanic ash found over them was too fine-grained to date with any certainty. Finally, though, the eruption has been determined to come from a volcano almost 250 miles, or 400 km, away from the remains. The Shala eruption was enormous and took place 230,000 years ago, so since the remains were found below the ash, the person had to have lived at least 230,000 years ago too.

We’re still learning more about humans and our closest relations because new hominin fossils are being found and studied all the time. But the fossil record doesn’t tell the whole story. Only a small percentage of bones ever fossilize, and of those, only a tiny fraction are ever found by scientists. But technological advances in genetic testing means that scientists can now extract DNA from the soil. All animals shed fragments of DNA all the time, from skin cells and hairs to poop. A study published in 2021 was able to isolate Neandertal DNA from sediments in three different caves. The DNA matched the known fossils found at the sites and gave more information besides. Instead of being restricted to a single individual whose bones were found and tested, genetic testing of sediments gives genetic information about lots of individuals. In the case of a cave in northern Spain, where lots of stone tools have been found but only a single Neandertal toe bone, it turns out that two different populations of Neandertal had lived in the cave over 100,000 years ago.

In episode 25, I mentioned that Neandertals didn’t seem to make things the way humans do, especially art. Some researchers even suggest that they couldn’t think symbolically the way humans do. But in the five years or so since that episode, we’ve learned a lot more about Neandertals–and they seem to have been pretty artistic after all.

The main problem is that historically, whenever scientists found rock art or carvings from prehistoric times, they assumed humans made it. We might be a little biased. Some art originally thought to be made by humans is now thought to have been made by Neandertals. Most of it is found in caves. Remains of animals are often found in caves because the cave protects them from weather and other factors that can destroy them, and the same is true for archaeological remains.

In 1990, a team of cavers dug into a narrow collapsed cave entrance and entered Bruniquel Cave in southwest France that no human—in fact, no animal from the surface world—had entered since the entrance collapsed during the Pleistocene. That was at least 24,000 years ago and probably much, much longer.

The cavers found the bones of long-extinct Pleistocene megafauna near the entrance, including cave bears. But it wasn’t until they reached a chamber deeper inside the cave that they made a stupendous discovery.

The chamber held a big stone circle made of broken-off pieces of stalactite and stalagmite and other rock formations. The pieces are all about the same size and are arranged in a circle almost 22 feet across, or 6.7 meters. There’s a smaller semicircle in the chamber too and heaps of more stone pieces. Some of the stones show signs of fires being lit on top of them, and a piece of burnt bone from a bear or other large animal was found near the semicircle.

The cavers alerted local scientists, who came to investigate. At first they thought the structures had been built by early humans. They took samples for testing, and that’s when they got another shock. The burnt bone, the fire residue, and the minerals growing over both revealed an age long before 40,000 years ago, which is when humans first moved into the area. The stone circle was built 176,000 years ago. And the only hominin known to live in Europe that long ago was the Neandertal.

We don’t know what Neandertals used the stone circles for. It might have been a living space, but it might have been religious in nature instead. Either way, it shows that even that long ago, Neandertals had full control over fire to the point that they could make light sources to find their way deep into a cave, and had the curiosity to want to explore deeper into a cave than they really needed to go for shelter.

There are lots of other examples of Neandertal art and intelligence found in Europe. For instance, paintings in a cave in Spain have been dated to at least 65,000 years ago. Remember, humans didn’t reach Europe until about 40,000 years ago. The paintings are made of red mineral pigment, including elaborate rows of dots, geometric figures, and occasionally animal figures and hand stencils. Other caves in the area also have similar rock art dating to Neandertal times.

In a cave in Germany, researchers found a piece of deer bone dated to 51,000 years ago that has a carved pattern in it. The carving is too elaborate to be simple butcher marks, but again, humans hadn’t yet moved into Europe 51,000 years ago. The bone actually comes from the leg of a giant deer, once called the Irish elk, that we talked about way back in episode 4. In another cave in Gibraltar, cross-hatched patterns carved in the rock have been dated to more than 39,000 years ago and are associated with artifacts made by Neandertals.

Archaeologists have also found a lot of toe bones from eagles that are etched with cut marks, found in various sites throughout southern Europe. They think Neanderthals in this area wore eagle talons as jewelry, and most likely feathers too.

There’s still controversy when it comes to Neandertals and art. Some researchers think Neandertals only used art after they saw humans making it. Some think the art isn’t art at all but something else, like accidental marks left by other activities. Some think the dating methods used to determine the age of paintings is flawed.

Another criticism is that we don’t actually know that Neandertals made the art; we just know it probably couldn’t have been humans. But there were other human relations living at the same time.

One of those is the Denisovan people, named for Denisova Cave in the mountains of Siberia. Hominins didn’t ordinarily live in caves, but sometimes they did. This seems to be the case in Denisova Cave, where evidence of human habitation, Neandertal habitation, and habitation by another hominin goes back some 180,000 years.

Researchers knew about humans and Neandertals living in the cave, but it wasn’t until 2010 that they realized a third hominin had lived there at various times. The Denisovan people were closely related to both Neandertals and humans and probably looked a lot like Neandertals, with a robust build and big teeth. We still don’t know a whole lot about them, but they lived in parts of what is now Asia and possibly nearby areas, and they might not have gone extinct until about the same time that Neandertals did, around 30,000 years ago.

We talked about the Denisovans in episode 25, but since then new remains have been discovered in other caves. The most exciting is a partial jawbone with two teeth that was found by a Buddhist monk in a cave on the Tibetan plateau in 1980, but not studied until much later. It was identified as a Denisovan mandible in 2019 and dated to 160,000 years ago.

Genetic testing of Denisovan remains indicate that Denisovans and Neandertals were probably more closely related to each other than to humans, although all three species were very closely related. Since there are so few Denisovan remains known, we don’t have a very good idea yet of where they lived and what they were like. We do have genetic markers that indicate the Denisovans had dark skin, brown hair, and brown eyes, while Neandertals, like humans, were more varied in skin, hair, and eye color.

Geneticists have identified traces of Denisovan DNA in some populations of modern humans, including in Asia, New Guinea and surrounding areas, and Australia. This is a reminder that even though some human populations contain DNA traces from our extinct cousins, all humans are thoroughly human. Those bits and bobs of ancient DNA are too small to be significant.

We do have what seems to be art made by Denisovans, although not everyone agrees that it was intended to be art in the way we think of it. It was found in the Tibetan Plateau and we now know that Denisovans lived in the area, although when it was found in 1998 we didn’t even know Denisovans existed. The art was found near hot springs and dated to as much as 226 thousand years ago, although it might have been closer to 169 thousand years ago. Either way, it was well before modern humans are known to have lived in the area. The art consists of footprints and hand prints pressed into the mud, probably by two individuals. The artists pressed their hands, feet, fingers, thumbs, and in one case a forearm into the mud around the hot springs, making patterns. But the thing is, these prints are small even by human standards. Researchers are pretty sure they were made by children, so while it’s certainly possible the children were creating art, they also might just have been messing around having fun in the mud. But the fact that they were making patterns points to an artistic intelligence. Puppies play and may stomp their feet in mud, but they don’t get interested in making patterns of their footprints in the mud. Human children do.

There’s still at least one other hominin that lived at the same time as Neandertals, Denisovans, and humans. We only know about that hominin because researchers have identified their DNA in genetic studies of Denisovans, which means they interbred. It’s a ghost lineage that no one guessed existed until genetic studies of Denisovans and Neandertals were completed in the early 2010s. It might turn out to be a known hominin such as Homo erectus but it might be a completely unknown species.

Of course we have lots of information about art made by ancient humans. It’s been found throughout the world. No one’s in any doubt that our prehistoric ancestors were just as intelligent and artistic as humans who live today, they just didn’t have the technology we have. I can go to an art supply store and buy paints in any color I want, assuming I don’t just want to paint digitally, but in prehistoric times human artists had to make their own paints from the things they found in nature. This included minerals like red ochre and yellow ochre, umber, calcite, hematite, iron oxide, and lots more. They used burnt bones and charcoal for black. These minerals are all still used to make modern oil paints (used in art, not for painting a room or a house), with names like bone black and lime white.

Many minerals have to be processed before they can be used as pigments. Ochre, for instance, has to be heated to 850 degrees Fahrenheit, or 750 Celsius, to change into the rich red-orange that ancient artists especially liked. After processing, the pigments were ground into powder, then mixed with various substances to make a paste. These substances included fat, blood, spit, plant oils, tree sap, water, bone marrow, and even urine.

Ancient artists used their fingers to paint, but they also used twigs, brushes made from animal hair, and mats of lichen. Sometimes they blew pigment onto a surface with their breath, first putting the paint into a hollow tube and then blowing into the tube to spray paint. This is the same way airbrushes work, but no one gets light-headed using an airbrush because a machine is doing the blowing air part. If the artist was working in a cave, they also needed a light source, specifically fire, so they could see what they were doing. It’s all a lot of work.

Aside from all the details involved in getting ready to paint, making art takes one other really important commodity: time. Great apes spend most of their time finding food and eating it. How did ancient humans find time to paint without starving?

A study released in early 2022 points out that hominins developed a much different strategy for getting food than our more distant ape relations. Apes mostly eat plant material, especially fruit, which is nutritious but takes a lot to fulfill the calorie needs of an adult. Early hominins were hunter-gatherers, meaning they both hunted animals and gathered plant material to eat. But because hominins are intensely social and share food, we could take risks that other animals can’t. A group of ancient humans could go out to hunt something big knowing that even if they failed, when they got home they wouldn’t go hungry. Other people would have been gathering food all day and would share. But if the hunters got lucky and brought home a big animal like a deer, everyone had lots and lots of high calorie food to go around. With food available to everyone, people could take time to do things that didn’t directly relate to finding food, like art.

Not only that, another study published in 2019 discovered that some early hominins had already figured out how to preserve food several hundred thousand years ago. The food in question was bone marrow, which is found inside bones and which is extremely nutritious. Researchers have always assumed hominins would crack the bones of animals they killed to get at the marrow as soon as possible. But deer bones found in a cave near Tel Aviv, Israel were stored unbroken, with the skin still on. Researchers determined that the bones were kept in the cave for up to nine weeks before being broken open. By keeping the skin on the bones and storing them in the cave, where the temperature was cool, the marrow stayed fresh. That way there was always something nutritious to eat in the cupboard, so to speak.

Art doesn’t have to be paintings or carvings. Ancient humans were probably using plant fibers to make things more than 34,000 years ago. The fibers are from wild flax plants, and flax is still used today to make linen fabric. Fragments of flax fibers were found in a cave in the Republic of Georgia (which is a country, not the American state of Georgia) where other human artifacts were found. Since flax isn’t edible, at least not by humans, researchers think the fiber might have been used to make thread, rope, baskets, and possibly even cloth. You know, clothing.

One thing to remember is that humans, Neandertals, and Denisovans were so closely related that they could and did interbreed and produce fertile offspring. That means not only were our extinct cousins very similar to us physically, they were probably pretty similar to us mentally too. It would be more surprising if they didn’t produce art that represented symbolic thinking, since it’s such an important part of the human experience.

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

Thanks for listening!

Episode 275: The Axolotl, the Hellbender, and Friends

This week it’s Zoe and Dillon’s episode! They wanted to learn about some really interesting salamanders, including the axolotl and the hellbender!

A big birthday shout-out to Heather R. too. The very happiest of birthdays to you!

Further reading:

Mexico City’s endangered axolotl has found fame—is that enough to save it?

How Do Salamanders Breathe?

Most wild axolotls are brown:

Most captive-bred axolotls are leucistic:

The hellbender doesn’t have external gills as an adult:

The red eft, the juvenile stage of the red-spotted newt:

Adult mudpuppies have external gills just like axolotls do:

Show transcript:

Welcome to Strange Animals Podcast. We’re your cohosts, Zoe and Dillon. And I’m your third cohost, Kate Shaw.

This week we have Zoe and Dillon’s episode, and they want to learn about the axolotl, the hellbender, and some other salamanders. It’ll be the greatest amphibian episode ever!

But first, we have a birthday shout-out! Happy birthday to Heather R.! I hope the weather is perfect for your birthday and you get to go out and appreciate it.

So, let’s start with the axolotl, because everyone loves it! “Axolotl” isn’t the way it’s pronounced in its native country of Mexico, since it comes from the name of an Aztec god of fire and lightning, but it’s the common pronunciation in English so I’m going to stick with that one. In addition to Zoe and Dillon, at least one other listener has suggested we cover the axolotl. That would be Rosy, and I apologize to anyone else who suggested it but whose name didn’t make it onto the suggestions list.

Way back in episode 104, about tiger salamanders, we learned that the tiger salamander is closely related to the axolotl. But the two species look very different most of the time because the axolotl exhibits a trait called neoteny. In most salamanders, the egg hatches into a larval salamander that lives in water, which means it has external gills so it can breathe underwater. It grows and ultimately metamorphoses into a juvenile salamander that spends most of its time on land, so it loses its external gills in the metamorphosis. Eventually it takes on its adult coloration and pattern. But the axolotl doesn’t metamorphose. Even when it matures, it still looks kind of like a big larva, complete with external gills, and it lives underwater its whole life.

Very rarely, an axolotl metamorphoses into an adult form, at which point it looks a whole lot like a tiger salamander. This generally happens if the individual is exposed to excess iodine in its diet, and metamorphosing like this may actually lead to the axolotl’s death. Axolotls exhibit neoteny because it gives them an advantage in their natural range, so even though it seems strange to us compared to all those other salamanders, it’s what the axolotl is supposed to do.

The axolotl’s natural range is very specific. Originally it lived in two large, cold lakes in the Valley of Mexico. This is where Mexico City is and it’s been a hub of civilization for thousands of years. A million people lived there in 1521 when the Spanish invaded and destroyed the Aztec Empire with introduced diseases and war. The axolotl was an important food of the Aztecs and the civilizations that preceded them, and if you’ve only ever seen pictures of axolotls you may wonder why. Salamanders are usually small, but a full-grown axolotl can grow up to 18 inches long, or 45 cm, although most are about half that length.

Also if you’ve only ever seen pictures of axolotls you may think they’re all white or pink. That’s actually rare in the wild. Most wild axolotls are brown, greenish-brown, or gray, often with lighter speckles. They can even change color somewhat to blend in with their surroundings better.

It’s captive axolotls that are so often white or pink, or sometimes other colors or patterns. That’s because they’re bred for the pet trade and for medical research, because not only are they cute and relatively easy to keep in captivity, they have some amazing abilities. Their ability to regenerate lost and injured body parts is remarkable even for amphibians, but, interestingly, axolotls that have been induced to metamorphose have much less regeneration ability. Researchers study axolotls to learn more about how regeneration works, how vertebrates evolved various aspects of anatomy, how genetics of coloration work, and much more. They’re so common in laboratory studies that you’d think there’s no way they could be endangered—but they are. Some conservationists think there may be as few as 50 individuals left in the wild.

The main problem is habitat loss. One lake where the axolotl was once found is completely gone, drained to control flooding and provide more land for people to use. The other lake isn’t so much a lake anymore as a series of canals in Mexico City, and they’re polluted and home to introduced species of fish that eat axolotl eggs. Even though part of their range was designated as a nature reserve in 1993, that hasn’t done much to stop the pollutants or invasive fish.

Not only that, the captive-bred axolotls are so different from their wild cousins that some people think they should be considered a different species. You couldn’t take a pet axolotl and dump it into a lake and expect it to live. Conservation efforts in Mexico are focusing on a captive breeding program of axolotls caught in the wild. Since the salamander’s native range isn’t healthy right now, the group is trying to establish temporary homes in university ponds prepared just for that purpose. So far the project is a success.

At the same time, conservationists and just regular people who like axolotls are working hard to get its native habitat cleaned up. This includes educating people about the axolotl, and helping people set up small farms that use traditional methods that don’t require fertilizer or insecticides that run off into the water. These farms are called chinampas and are made up of artificial islands with canals around them. The islands actually help filter pollutants from the surrounding water, and the canals are ideal for axolotls to live in. The farmers also install screens with filters to keep invasive fish out and clean up the water even more, and some of the captive-bred wild axolotls have been introduced to these canals successfully.

Even though the axolotl has external gills to collect oxygen from the water, it has lungs too. It will sometimes gulp air from the surface, but most of the time it gets all the oxygen it needs from its gills. It eats small animals like worms, insects, and even small fish, but while it does have tiny teeth, they’re actually vestigial. The axolotl doesn’t chew its food but instead sucks its prey whole right down into its stomach.

We talked about the hellbender briefly in episode 14, but that was five years ago. In fact, it was exactly five years ago. Episode 14 was released on May 8, 2017, and this episode is being released on May 9, 2022. I swear I did not plan it that way but it’s pretty neat.

The hellbender has a restricted range too, although it’s not as restricted as the axolotl’s. It lives in parts of the eastern United States, especially in the Appalachian Mountains and the Ozarks. It can grow nearly 30 inches long, or 74 cm, and is heavy for its size, up to 5.5 lbs, or 2.5 kg. This is the fifth heaviest amphibian alive today in the whole world! It needs clean, shallow, fast-moving streams with lots of rocks, because it spends almost all its life in the water hiding among rocks. But the rocks are important for another reason too. As water rushes over and around rocks, it splashes around and absorbs more oxygen. Well-oxygenated water helps the hellbender breathe, which is even more complicated than it sounds.

Like other salamanders, the hellbender hatches from eggs laid in the water and at first are just big tadpoles with external gills. They metamorphose in stages until they’re full grown at almost two years old, at which point they lose their gills, although they may retain a nonfunctioning gill slit. The adult hellbender has large lungs, but it doesn’t use them for breathing. They’re just for buoyancy. The hellbender absorbs oxygen from the water through its skin, which is why it needs well-oxygenated water flowing quickly across it all the time. To increase its surface area and help it absorb that much more oxygen, its skin is loose and has folds along the sides.

The hellbender is flattened in shape, which helps it hide under rocks and helps keep it from being swept away by currents when it’s moving around in the water. It’s brown with black speckles on its back. It mostly eats crawdads, also called crayfish, but it will eat small fish and amphibians, tadpoles, the eggs of frogs and fish, and in fact it will also eat the eggs of other hellbenders. Occasionally a hellbender will eat a smaller hellbender too. It’s a solitary animal except during breeding season, and even then, once the female has laid her eggs in a nest the male makes and the male fertilizes them, the pair don’t spend any time together. The male actually chases the female away. Then he spends the next few months guarding the eggs and making sure they get enough oxygen by waving his tail and skin folds over them.

The hellbender doesn’t have very good eyesight, although it has a good sense of smell. It’s very territorial and seldom leaves the small stretch of water where it lives and hunts. Very occasionally it will leave the water and walk around on land. Most of the time it walks around underwater, though, instead of swimming. Its toes have rough pads that help it walk even on slippery rocks. During the day, though, it usually hides under its home rock. Its skin contains light-sensitive cells, which are mostly concentrated in its tail. This means that it can actually sense how much light is shining on its body even if its head is hidden under a rock. The reason its tail has more light-sensing cells is because its tail is more likely to be sticking out from under its rock. Since a lot of animals eat the hellbender, it needs to be fully hidden by its rock during the day.

Some people think the hellbender is poisonous or venomous, but it’s actually completely harmless unless you are a very small aquatic animal.

Because salamanders, like other amphibians, have to keep their skin moist, they’re vulnerable to water pollution. Any pollutants in the water are liable to be absorbed into the salamander’s body, which can make it sick. Habitat loss, disease, and invasive species are also major causes of declines in salamander species.

Salamanders have been around for at least 180 million years. Amphibians in general probably developed from lobe-finned fish around 360 million years ago. A study published in 2020 examined 3D scans of skulls from 148 species of salamander to compare minute differences and learn more about how they evolved. Animals that undergo metamorphosis, including salamanders, have very different skulls from animals that don’t, since different parts of the skull develop in stages independently of other parts. The study found that while salamanders have always been metamorphic, different life cycles have evolved separately at least eleven times.

One of the things Zoe asked in particular was whether salamanders actually breathe through their nostrils. It depends on the species. Salamanders are definitely complicated when it comes to breathing. Like many amphibians, the salamander doesn’t have special muscles to move air in and out of its lungs the way mammals do. Instead, it moves air in and out by gular pumping, also called buccal pumping.

A salamander lowers the floor of its mouth, expanding the throat, which pulls air into the throat by way of the nostrils. Then the salamander closes its nostrils and raises the floor of its throat. This causes the air to enter the lungs. It does the same process in reverse to breathe out. That’s why salamanders and other amphibians appear to be gulping all the time. That’s how they breathe.

Complicated as this sounds, the salamander doesn’t have to concentrate to do it any more than we have to concentrate to breathe. Also, even if it mostly gets oxygen through its lungs, all salamanders appear to be able to absorb a certain amount of oxygen through the skin too.

Zoe and Dillon were especially interested in salamanders that live in their part of the world, which is the state of Pennsylvania in the eastern United States. In addition to the hellbender, there are several dozen salamander species known from Pennsylvania, and probably quite a few that haven’t been discovered yet. This includes the red-spotted newt, which lives in forests in muddy or wet areas. It grows up to about 5 inches long, or 13 cm, and eats insects, worms, frog eggs and tadpoles, and other small animals.

As an adult, the red-spotted newt is greenish-brown, often with a row of red spots outlined with black along its sides and tiny black dots all over, and a yellow or orange belly. The adult mostly lives in the water, but during the juvenile stage it mostly lives on land and can travel widely, especially after rain. It also looks very different during the juvenile stage, with a bright orangey-red body and spots outlined with black, which is why it’s often called a red eft. An eft is a juvenile salamander. The bright red coloring may tell you not to eat the red eft, because it’s poisonous! Its skin contains toxins that make it taste bad and can make a potential predator sick.

Another salamander common throughout Pennsylvania is the spotted salamander, which can grow almost 10 inches long, or 24 cm. It’s a big, strong salamander that’s black or gray with big yellow or orangey spots all over. As a juvenile it looks very similar, although smaller, but with tiny spots or no spots.

Finally, to wrap around to where we started, another large species of salamander that lives in parts of western Pennsylvania, and other nearby areas, is the mudpuppy. It looks a lot like a juvenile hellbender but isn’t as big, with the largest measured adult growing just over 17 inches long, or almost 44 cm. Like the axolotl, the mudpuppy exhibits neoteny. It lives in lakes, ponds, and streams and retains its gills throughout its life. Its gills are large and reddish in color. If a mudpuppy lives in your pond or backyard stream, you can be sure the water is clean because its gills are very sensitive to pollutants.

The mudpuppy spends most of its time under rocks and walking along the bottom of the lakebed or streambed, looking for food. It’s gray, black, or reddish-brown, sometimes with speckles or spots. It has a lot of tiny teeth where you’d expect to find teeth, and more teeth on the roof of its mouth where you would not typically expect to find teeth. It needs all these teeth because it eats slippery food like small fish, worms, and frogs, along with insects and other small animals.

Even though the mudpuppy has all those teeth, it’s harmless to humans and just wants to be left alone, but that’s pretty much the case for all salamanders. And some people.

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

Thanks for listening!

Episode 274: Mystery Big Cats in Australia

Thanks to Kristie and Jason, we’re going to learn about some mystery big cats reported in Australia, in particular Victoria.

Further reading:

Official big cat hunt declared a bust, so why do people keep seeing them?

Further watching:

Thylacine video from 1933, colorized

You’ll probably need to enlarge this but it’s a still from a 2018 video purportedly showing a mystery big cat, but in this frame you can see the ears are pointy, which is a sure sign of a domestic cat:

A melanistic (black) leopard and regular leopards (picture from this site). If you zoom in you can see the spot pattern on the black leopard:

A puma/cougar/mountain lion. Note the lack of spots:

A thylacine. Note the lack of spots but presence of stripes:

Show transcript:

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

This week is Kristie and Jason’s episode. They want everyone to learn about mysterious big cats in Australia!

Australia, of course, is home to many wonderful animals, but almost all of the native mammals are marsupials. There are no native felids of any kind in Australia, even in the fossil record. This is because Australia split off from the rest of the world’s landmasses when the supercontinent Gondwana broke apart. Marsupials actually first arose in South America and spread to Australia when the two landmasses were connected. Then, around 180 million years ago, South America and Africa split off from the rest of Gondwana, including Australia. Most of South America’s marsupials went extinct as placental mammals arose and became more and more numerous, but Australia was on its own starting about 30 to 50 million years ago. Marsupials never had to compete with placental mammals during most of that time, except for bats, and the marsupials thrived.

Humans first populated Australia at least 41,000 years ago and probably more like 65,000 years ago. The first dingoes, a type of dog, were introduced around 5,000 years ago. The first European sighting of Australia was in 1606, and less than 200 years later the British colonized the continent, bringing with them invasive species like cats, rats, cattle, sheep, foxes, rabbits, deer, and lots more, which have driven many indigenous animals to extinction. But while domestic cats are common in Australia, as far as we know no one has ever deliberately released enough big cats to form a breeding population.

In that case, though, why are there so many reports of big cats in parts of Australia?

If you remember way back in episode 52, where we talked about big cats in Britain, there were lots of stories and a certain amount of evidence that individual big cats were occasionally found in the country. Ultimately, though, there’s no proof of a breeding population of big cats. The same is more or less true in Australia, but Australia is so much bigger and so much less populated than Britain, it would be easy for a small population of big cats to hide. And maybe they’re not actually big cats but some other animal, something that is native to Australia.

Kristie and Jason have lots of experience searching for big cats in central Victoria, Australia. They even helped with the research of a book about big cat sightings. Victoria is in southeastern Australia and is the smallest state. If you walked south from central Victoria to the coast, and then got on a boat and kept going south, you’d run into Tasmania. If you walked north instead, eventually you’d come to New South Wales but that is going to be a long walk. Victoria is mostly temperate and rainy but has tall mountains, semi-arid plains, and lots of rivers.

As Kristie pointed out, different parts of Australia have different stories about mystery big cats, but I’m mostly going to talk about sightings in Victoria, just to narrow it down.

To start us off, now that we have some background information, here’s a clip from the conversation I had with Kristie. The audio isn’t great, unfortunately, but it’s definitely interesting.

[quote of Kristie’s account:]

“Jason and I used to go puma hunting. It was very scary. So, there was this bloke we used to go and visit. I’m not going to name any names; I’m not even going to tell you exactly where he was other than he was in Castlemaine along a railway line, a disused railway line. So, the story goes that this man (let’s just take 80% of what he says with a grain of salt), he’d gone up to get a horse from a paddock outside their house that they lived in, on a dirt road near the railway. There was lots of long grass on the side of the road. He said he went to get the horse and was bringing the horse back to the house paddock, and he felt like he was being watched. Not a good feeling. And then he heard something that sounded like a growl coming from in the grass. And the horse had a bit of a moment. He continued on his way—he was safe, the horse was safe! No animals were hurt in the making of this story. From then on he said he and his wife would hear things walking around their house and it would just feel really weird. They would say that they actually saw these cats walking along the road.

“I would call Jason and we’d get on a motorbike and we’d go down, probably about a 5 or 10 minutes motorbike ride. Of course whenever we got there, there was nothing there. Occasionally you might see something on the dirt road, because there was a bit of fine dirt on there that maybe you could find a footprint on there.

“You would hear dogs bark, hear them off in the distance when whatever it was out there was on the move. It would actually follow the creek down and the railway line and you would get a succession of dog barks.”

Kristie went on to say that they’d even found and taken a plaster cast of a large paw print that looked different from a dog’s print, but the veterinarian they took it to wasn’t able to determine whether it was made by a big cat or just a dog.

She also talked about some other evidence that their friend gave as proof of big cats living in his paddock, including swirls in the long grass that looked like a cat had flattened the grass to sleep. In that case, she also pointed out that the same thing had happened in her own yard recently and that she was pretty sure it was caused by the wind. But here’s another clip from her about an experience she had that wasn’t so easy to explain:

[quote of Kristie’s account:]

“I spent one night out in a caravan that they had in their yard, just waiting, and I heard a cough. Pumas cough, but so do kangaroos, so I don’t know. I didn’t see any kangaroos. I like to think I heard a puma cough. I honestly don’t know what I heard.”

Kristie even thinks she spotted a big cat once as she and Jason rode by on a motorbike, but by the time she realized what she’d seen, it was long gone. She said it was a large black animal with a very long tail, much longer than a domestic cat’s tail.

One theory of big cat sightings is that they’re descendants of cougars, also called pumas or mountain lions, brought to Australia as mascots by American troops during World War II but released into the wild. While WWII units from various countries did often have mascots, they were usually dogs. A few mascots were domestic cats, there were a couple of pigs, birds, and donkeys, but mascots were almost always domesticated animals that a unit adopted even though they weren’t really supposed to have them. Wild animals were rare as mascots because they were hard to handle and hard to hide from officers. While there were certainly some big cats of various kinds brought to Australia by American soldiers and released when they started getting too big and dangerous to handle, or when they were found by officers, there wouldn’t have been enough to form a breeding population.

Besides, big cat sightings go back much earlier than the 1940s. Some people blame Americans again for these earlier stories, specifically American miners who came to Australia in the mid-19th century gold rush. Supposedly they brought pet cougars that either escaped or were released into the mountains. While miners did bring animals, they were almost always dogs or pack animals like mules.

More likely, though, any big cats escaped or released into the Australian bush in the olden days came from traveling circuses or exotic animal dealers. Even so, again, there just weren’t enough big cats of any given species to result in a breeding population. But, also again, people are definitely seeing something.

The most compelling evidence for big cats in Australia is attacks on large animals like horses, cattle, calves, and sheep. Australia doesn’t have very many large predators. Dingoes are rare or unknown in Victoria these days, as are feral pigs, foxes don’t typically hunt animals larger than a rabbit or chicken, and feral dogs usually leave telltale signs when they attack livestock.

In 2012, the Victorian Department of Sustainability and Environment commissioned a study of big cat sightings in the state. The study’s aim was to determine whether a breeding population of big cats might exist, and if so, what impact it was having on the native wildlife. The team examined historical and contemporary reports of big cats, and studied photos and videos and other evidence. Its findings were inconclusive—there just isn’t enough evidence that big cats are living in Victoria, although it couldn’t rule it out either—and it recommended further investigation.

An earlier study in the 1970s by Deakin University also attempted to determine whether big cats lived in the Grampians, a national park that includes a mountain range. Its traditional name is Geriwerd. The study came to the conclusion that there probably were pumas in the Grampians, but one of the pieces of proof, a 3-inch, or 8-cm, fecal pellet, was later identified as a pellet regurgitated by a wedge-tailed eagle.

Kristie also mentioned that the wedge-tailed eagle might be the source of some claw marks found on wildlife. The wedge-tailed eagle is a large, robust bird with a wingspan over nine feet across, or 2.84 meters, and it lives throughout Australia and southern New Guinea. It’s mostly black or brown in color and has a large hooked bill and large, strong talons. It often hunts in pairs or even groups and can kill animals as large as kangaroos. Larger species of wallabies and other native animals are the eagle’s natural prey but it also eats lots of introduced animals like rabbits and foxes, and occasionally kills lambs or piglets. It also eats a lot of carrion.

Eagle attacks don’t explain everything, though, such as claw marks found on horse rugs. Horse rugs are special blankets that horses wear, especially in cold weather. There are also reports of dead sheep and goats found dragged into trees or through fences, something a dog couldn’t or wouldn’t do but a leopard or other big cat could.

In 1991 a piece of poop, more properly called scat or feces, was turned into authorities and sent for testing. Initially reports said it looked like it came from a large felid, although what species couldn’t be determined. Fortunately it was saved and was genetically examined a decade or so later, at which point it matched up to a leopard. Assuming it was actually found in the bush and wasn’t a joke by an exotic pet owner, it means there was a leopard running around in central Victoria a few decades ago for sure.

Most sightings of Australian big cats fall into two categories: black cats and tan or gray-brown cats with white bellies. As we learned in last year’s wampus cat episode, the cougar is tan or gray-brown in color, sometimes called yellowish, with a pale belly, but is never black. Melanism is common in some big cats, especially leopards and jaguars, but leopards and jaguars are always spotted. Even melanistic individuals show a faint spotted pattern up close. So if some Australian big cats are black and other Australian big cats are tan or gray-brown without spots, they’re probably not the same species. But now it’s even more complicated! How could there be two species of big cat hiding so close to people without anyone hitting one with a car or shooting one in a pasture or just getting a really good picture of one on a trail cam or just a phone?

A lot of people think that feral domestic cats are responsible for all the sightings. While some feral cats can grow larger than average for a domestic cat, especially in areas where there’s lots to eat, most are actually quite small and thin. Feral cats are definitely responsible for a lot of big cat sightings, but not all. Black domestic cats in particular stand out in fields and on bright days so might be noticed more often than other colors of cat, and it’s easy to see a big black cat in the distance, not very close to anything, and assume it’s larger than it really is. But pictures and videos of these cats are usually pretty easy to identify as domestic. Domestic cats have pointy ears set high on the head, unlike big cats who have rounded ears that are lower on the head.

One video from 2018 is often cited as proof of a big cat in Australia, although in this case it’s in New South Wales. If you check the show notes, you’ll see a still I took from the video showing the animal’s ears. They’re pointy ears so the animal has to be a domestic cat.

There’s always another possibility, of course. Maybe the big cats aren’t cats at all but rare, reclusive carnivorous marsupials. The two main contenders are the marsupial lion and the thylacine.

The marsupial lion, or Thylacoleo carnifex, isn’t actually a lion. It’s a marsupial, and in fact I should say it was a marsupial because it went extinct at least 30,000 years ago as far as we know. It was probably almost as big as a lion, though, with massive jaws and teeth that could bite through bones. It ate large animals like the giant wombat relation Diprotodon and giant kangaroos, so it would have no trouble with a sheep.

But the marsupial lion didn’t actually look like a lion either. It probably resembled a small bear in some ways, although it had a thick tail more like a kangaroo’s than a cat’s. Its method of hunting doesn’t match up with the dead animals found in Victoria either. The marsupial lion had huge claws that it used to disembowel its enemies, I mean its prey, whereas modern big cats mostly use their strong jaws to bite an animal’s neck. Also, of course, the marsupial lion went extinct a really long time ago. While there’s always a slim possibility that it’s still hanging on in remote areas, I wouldn’t place any bets on it. I don’t think it’s the real identity of the mystery big cats. There are just too many discrepancies.

The thylacine, also called the Tasmanian tiger because it lived in Tasmania and had stripes, was about the height of a big dog but much longer. It was yellowish-brown with black stripes on the back half of its body and its tail. It had relatively short legs but a very long body and its tail was thick. It was a carnivorous marsupial, mostly nocturnal.

The thylacine went extinct in mainland Australia around 3,000 years ago while the Tasmanian population was driven to extinction by white settlers in the early 20th century. But like big cat sightings, people still report seeing thylacines. Maybe people are mistaking thylacines for big cats, since a quick glimpse of a big tawny animal with a long tail could resemble a puma if the witness didn’t see its stripes or didn’t notice them in brush or shadows.

The thylacine wasn’t a very strong hunter, though, at least as far as researchers can tell. But there’s a lot we don’t know about the thylacine even though it was still alive less than 100 years ago. As Kristie says:

“Maybe it was a thylacine. Who knows?”

Kristie and Jason think most big cat sightings are explainable as feral cats and other known animals. They also pointed out that what appear to be unusual predation methods might just be caused by more than one kind of animal scavenging an already dead carcass.

But there are lots of sightings that can’t be explained away, and people occasionally find dead animals that look like they’ve been killed and eaten by a big cat instead of a dog or eagle. While there’s a low probability that a breeding population of big cats is living in Victoria, there’s a very good chance that a few individual animals are. They’re most likely escaped or released exotic pets, possibly ones that were kept illegally in the first place.

As Kristie and Jason point out, people often freak out when they’re confronted with something strange, like the possibility that a leopard is sneaking around their house. You can’t really blame them. That’s why it’s so important to find out more about these animals, because turning the unknown into the known helps people know what to do and not be so scared.

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

Thanks for listening!

Episode 273: Noisy Invertebrates

Thanks to Isaac, Joel, Ethan, and Richard E. for their suggestions this week!

Don’t forget to check out our crowdfunding campaign for some cute enamel pins!

Further reading:

Snapping Shrimp Drown Out Sonar with Bubble-Popping Trick

One example of a pistol shrimp–there are many, many species (photo from this site):

A walnut sphinx moth sitting on someone’s hand (photo by John Lindsey, found on this page):

A caterpillar (photo by Ashley Bosarge, found on this page):

The Asian longhorned beetle (from this site):

The white-spotted sawyer pine beetle is another type of longhorned beetle:

Show transcript:

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

It’s been too long since we’ve had an invertebrates episode, so this week let’s learn about some invertebrates that make noise. Thanks to Isaac, Joel, Ethan, and Richard E. for their suggestions!

We don’t have a birthday shout-out this week, but we do have a reminder that the next five episodes, the ones releasing in May, are our Kickstarter episodes! Those are from the Kickstarter level where the backer got to choose the topic and work with me to craft the episode. I’ve been amazed at how fantastic those episodes turned out, and I think you’ll like them.

Speaking of crowdfunding campaigns, a quick reminder that the Tiny Pin Friends Indiegogo is still going on. It’s sort of stuck halfway to our goal, probably because I got busy with the book release and haven’t been telling people about the pins, so if you want to take a look at the pin designs, there’s a link in the show notes. Thanks!

Now, on to the invertebrates! Both Isaac and Joel suggested the same topic at different times, pistol shrimp. This is a group of shrimps also called snapping shrimps. Most species live in warm, shallow coastal habitats like coral reefs, but some live in colder water and at least one lives in freshwater caves.

The pistol shrimp only grows a few inches long at most, or about 5 cm. It gets its name from its big claw, which functions in a similar way to the workings of a pistol (sort of). But instead of shooting bullets, the claw shoots bubbles—but so incredibly fast, they might as well be bullets.

A pistol shrimp has two claws, but one is small and used for picking stuff up and grabbing food. The other claw is the pistol claw that’s much bigger and stronger. Which claw is which depends on the individual, and if a shrimp’s pistol claw gets damaged or bitten off, its other claw will develop into a pistol claw. The damaged or lost claw eventually regenerates into a little claw for manipulating food.

The pistol shrimp is mostly an ambush hunter. It will hide in a burrow or rock crevice with its antennae sticking out, and when a small animal like a fish happens by, the shrimp will emerge from its hiding place just far enough to get a good shot at the animal. It opens its big claw and snaps it shut so fast and so forcefully that it shoots tiny bubbles out at speeds of over 60mph, or 100 km/hour. Obviously the bubbles don’t travel very far at that speed, really only a few millimeters, but it’s powerful enough at this short range to stun or outright kill a small animal. The shrimp then grabs its stunned or dead prey and drags it back into its hiding spot to eat.

The process is way more complicated than it sounds. When the claw opens, water rushes into a tiny chamber in the claw. When it snaps closed, a tiny point on the claw pushes into the chamber, which leaves no room for the water. The water is therefore forced out of the chamber at such incredibly high pressure that it leaves vapor-filled cavities in the water, the bubbles, which collapse with a loud snapping sound. The pressure wave from the collapsing bubble is what actually kills or stuns an animal. Physics! I don’t understand it! Check the show notes for an article that goes into more detail about this process, which I’ve hopefully described correctly.

The bubble’s collapse makes such a loud noise that the pistol shrimp is one of the loudest animals in the ocean, but the sound lasts for less than a millisecond. It takes 100 to 400 milliseconds for you to blink your eye, to give you a comparison. The collapsing bubble also produces light and intense heat, but it’s such a tiny bubble with such a limited range that the heat and light don’t make any difference. The light isn’t very bright and lasts such a tiny amount of time that the human eye can’t even perceive it.

The pistol shrimp doesn’t only use its big claw to hunt for food and defend itself from potential predators. It also communicates with other pistol shrimp with the sound, and pistol shrimp can live in colonies of hundreds of individuals. With them all snapping together, no matter how short each snap is, the collective sound can be incredibly loud—so loud it interferes with sonar in submarines.

This is what it sounds like, although it also kind of sounds like popcorn popping, if you ask me:

[snapping shrimp sounds]

Next, Ethan suggested the walnut sphinx moth, because his son found one, they looked it up, and they were both amazed at how awesome it is. It lives in the eastern part of North America and is a big, robust moth with a wingspan up to 3 inches across, or 7.5 cm. Its wings and body are mostly brown and gray, often with darker and lighter markings but sometimes all one color. The edges of its wings have an uneven scallop shape and when it perches, it spreads both pairs of wings out in a sort of X shape. Its wing shape and coloring make it look a lot like an old dead leaf.

Like many moths, the walnut sphinx moth doesn’t eat at all as an adult. After it metamorphoses into an adult, it only lives long enough to mate and lay eggs. It spends most of its life as a caterpillar, where it eats the leaves of various kinds of trees, especially nut trees, including walnut, hazelnut, and hickory. The caterpillar is a pretty green with tiny white dots all over and yellow or white streaks along its sides, although some individuals are red, orange, or pink instead of green. It has a red or green horn on its tail end.

The most amazing thing about this moth is how the caterpillar keeps from being eaten. Lots of animals like to eat caterpillars, especially birds, but when a bird tries to grab this caterpillar, it thrashes around and actually makes a sound! You don’t typically think of caterpillars as noisy. It’s actually not very loud, but it does make a little whistle that mimics a bird’s alarm call, and can make a little buzzing sound too. The caterpillar makes the sound through its breathing tubes, called spiracles.

Researchers have played the caterpillar’s whistle sound at bird feeders and the birds react as though they’re hearing a bird making an alarm call.

This is what the whistle sounds like [whistle] and this is what the buzzing sounds like [buzz].

Richard E. recently tweeted some amazing pictures of beetles and suggested we cover more beetles, and I totally agree! We’ll finish with a beetle that makes this weird creaky sound:

[beetle sound]

The Asian longhorned beetle is sometimes called the starry sky beetle because it’s black with white dots. It’s native to eastern China and Korea, but it’s an invasive species in North America, parts of Europe, and other parts of Asia. It can grow about an inch and a half long, or 4 cm, but its antennae are up to twice as long as its whole body.

The female chews little holes in the bark of a tree and lays a single egg in each hole. When the larva hatches, it burrows deeper into the tree, eating sap and wood, until it’s ready to pupate. When it emerges as an adult, it chews its way out of the tree for the first time in its life, and flies away to find a mate. It especially likes poplar, maple, and willow trees. If enough beetle larvae are eating their way through a tree, the tree becomes weakened and can lose branches or even die.

There are lots of other species of longhorned beetle, though, and a lot of them make creaky scraping sounds. The male has ridges on his head that he scrapes along his thorax to attract a mate.

The white-spotted sawyer, also called the pine beetle, is native to North America and is black with a single white spot at the base of the wings, and sometimes with more white spots on the wings. It looks a lot like the Asian longhorned beetle but has black antennae whereas the Asian beetle has black and white antennae.

Like the many other longhorned beetle species, the female chews little holes in a tree to lay eggs in, but in this case she prefers pine and spruce trees, especially ones that are dead or dying or have sustained fire damage. The male white-spotted sawyer finds a good tree and defends it from other males, and if a female likes the tree she’ll mate with the male. But while the male keeps other males away, other females sometimes sneak in and lay eggs in the holes the female has already chewed in the tree. These nest holes take a long time to make and if a female can sneak some of her eggs into holes another female has already made, it saves her a lot of effort.

In addition to the male making a creaking noise to attract a mate, longhorned beetle larvae just generally make a lot of noises as they chew their way through a tree. If you’re ever walking through the woods and hear this sound, now you know what it is:

[creaky beetle sound]

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

Thanks for listening!

Episode 272: The Waitoreke

Thanks to Sarah L. for buying the podcast two books off our wishlist! This episode was inspired by an entry in one of those books!

A very happy birthday this week to Matthew!

Don’t forget that you can still contribute to our Indiegogo “Tiny Pin Friends” campaign to get a small hard enamel pin of a narwhal, a capybara with a tangerine on its head, and/or a thylacine!

On April 19, 2022, the book Beyond Bigfoot & Nessie: Lesser-Known Mystery Animals from Around the World goes officially on sale in paperback everywhere! (The ebook is already available.) Bookstores in the U.S. can order fully returnable copies at a standard bookstore discount; bookstores outside of the U.S. still get a discount but the copies are non-returnable. The book should be available to order anywhere you usually order books, including Amazon and Bookshop.org!

Further reading:

Rakali/Water-rat–Australia’s “otter”

Additional Sources (because this episode turned out to be really hard to research):

Conway, J., Koseman, C.M., Naish, D. (2013). Cryptozoologicon vol. I, 37-38. Irregular Books.

Ley, Willy. (1987). Exotic Zoology, 291-295. Bonanza. (Original work published 1959)

Pollock, G. A. (1970). The South Island otter: A reassessment. Proceedings (New Zealand Ecological Society), 17, 129–135.

Pollock, G. A. (1974). The South Island otter: An addendum. Proceedings (New Zealand Ecological Society), 21, 57-61.

Worthy, T. H., et al. (2006). Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific. Proceedings of the National Academy of Sciences of the United States of America103(51), 19419–19423. https://doi.org/10.1073/pnas.0605684103

An otter with its telltale bubble chain (Photo by Linda Tanner):

A rakali swimming (photo by Con Boekel, from website linked to above):

Show transcript:

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

This week we have a fascinating mystery animal from New Zealand! Many thanks to Sarah L., who very generously bought me a couple of books off my podcast wishlist, which I tend to forget is even a thing that exists! One of the books is Cryptozoologicon, Volume 1 by John Conway, C.M. Koseman, and Darren Naish, and that’s where I got this week’s topic, the mysterious waitoreke. [why-tore-EH-kee]

This week is also special because the paperback version of our own book, Beyond Bigfoot & Nessie: Lesser-Known Mystery Animals from Around the World, officially goes on sale on April 19, 2022. That’s tomorrow, if you’re listening to this the day the episode goes live. It should be available to order everywhere you ordinarily buy books, throughout the world. The ebook is available too. I’ve mailed all Kickstarter copies so if you haven’t received your copy yet, let me know. There were a few people who never returned the backer survey so I don’t have those addresses to mail books to. If you want a signed copy of the book at this point, or a hardback copy, you’ll need to catch me in person. I’ll be at ConCarolinas over the first weekend of June and I’d love to meet up with you. I’m working on the audiobook now, for those of you waiting for that one. (It’s a slow process, so don’t expect it for at least another month, sorry.)

You know what else is happening this week? A birthday shout-out! Happy birthday to Matthew! I hope your birthday is everything you ever hoped for in a birthday, or maybe even more!

New Zealand has almost no native mammal species except for a few bats, some seals and sea lions that live along the coast, and some whales and dolphins that live off the coast. Lots of mammals have been introduced, from dogs to rats, cattle to cats, but there are reports of a small mammal in New Zealand called some version of waitoreke, supposedly a Maori word meaning something like swift-moving water animal. Even the animal’s name is confusing, though. No one’s sure whether the word is genuinely Maori. The animal is also sometimes referred to as the South Island otter, the New Zealand platypus, the New Zealand muskrat, or the New Zealand beaver.

Reports of the animal go back a couple of centuries, basically as soon as Europeans stumbled across the country. One of the earliest reports is from 1861 by Julius von Haast, a geologist who spent many years surveying the geography and geology of New Zealand, and who made a lot of discoveries along the way. The huge, extinct Haast’s eagle is named after him, for instance, since he was the first European scientist to examine its remains. In June of 1861, Haast spotted some tracks in the mud along a riverbank, which he noted looked like an otter’s tracks but smaller. Two shepherds in the area claimed they’d seen the animal and that it was the size of a large rabbit with dark brown fur. Haast seems to be the first person to have used the word waitoreke, but a naturalist named Walter Mantell might have used the word first—it’s not clear.

The Maori people of the South Island also reported seeing the animal. One man even said it had sometimes once been kept as a pet, although he may have actually been referring to the tuatara, a reptile we talked about way back in episode 3. The waitoreke was supposed to be about two feet long, or 61 cm, not counting its bushy tail, brown in color, with short legs, and a head that was something between a dog and cat’s head. It spent most of its time in the water but it also came on land and lived in a burrow.

The problem with these accounts is that they were mainly gathered by Walter Mantell, who was not Maori. He might have misunderstood some details or not recorded them accurately. Most of the details we have come from an interview with a Maori chief whose name Mantell recorded as Tarawhata, although this may have been incorrect. Tarawhata said that there were two types of waitoreke, a water type and a land type. The land type ate lizards, the water type ate fish. He might have been referring to two different animals or he might have been referring to the same animal living in two different habitats.

We don’t even know when Mantell talked to his witnesses except that it had to have been sometime after about 1840 when he first came to New Zealand. We don’t have Mantell’s original notes, either. The details come from a paper presented by Mantell’s father, a zoologist, to the Royal Zoological Society of London in November 1850. For that matter, we don’t have Haast’s original notes about the footprints he spotted in 1861. His account was reported in a book by another geologist, published in German in 1863, with an English version in 1867.

There have been more recent sightings of the waitoreke, though. A fisherman named A.E. Tapper spotted what might have been a waitoreke six times between 1890 and 1921, which he wrote about in 1926 in letters to the Southland Times. He described the animal as a dark mousy brown with a rounded head like a seal’s, about the size of a possum or rabbit. In his account of the last sighting, in 1921 while he was fishing the Waikiwi River near an abandoned bridge, he wrote, “[s]omething…splashed, dived into the water and swam past me upstream, disappearing under some scrub on the other side. It was dusk, the water dark, yet I was close enough to distinguish a dark shadowy form 18 inches, or two feet deep [about 45 to 60 cm]. The wake it made in the water showed it to be of some size, but the strangest part was the noise it made when going through the water and the numerous bubbles that followed in its track. The noise was exactly that made by throwing a handful of…small stones in the water… I went down next day but beyond finding tracks in the mud similar to a rabbit’s but apparently webbed I found no trace.” He also found a hole in the bank several months later after the water level had dropped, meaning the hole had previously been underwater even though it looked like a rabbit burrow.

Unfortunately, while we know exactly where this sighting took place, by 1970 the surrounding marshlands had been drained and cleared for crops, and the river was so polluted that basically nothing lived in it anymore.

In 1957, a woman named Mrs. Linscott saw an animal swim across a big pond, which was connected to the nearby Aparima River. She only saw its head and the front of its body since it vanished into brush at the far end of the pond, but she got a good look at it while it swam. It had a small head with protuberant eyes and round ears, its face was “browny-purple,” and it had whiskers.

In 1968, a man named Bob Thompson was on holiday near the Whakaea River. He got up at dawn one morning and saw an animal emerge from a creek, followed by three young ones who disappeared into some brush. The difference in this case is that Thompson was from Norfolk, England and had lived next to the River Yare, where otters were common at the time. He said these animals were definitely otters.

In 1971, a man named P.J.A. Bradley had returned from an unsuccessful deer hunt near the Hollyford River and was waiting for the boat to take him home when he heard splashing in a quiet inlet nearby. He thought it might be a deer so he approached cautiously. Instead of a deer, he saw an animal playing on the riverbank by repeatedly climbing up and sliding down the mud into the water. He said the animal was dark brown and smooth with a thick tapering tail, short legs, and small head with no noticeable ears. He estimated that it was as much as 3.5 feet long, or 107 cm, including the tail.

All these reports really do sound like otters. We talked about the Eurasian otter in episode 37, about the Dobhar-Chu. It’s a shy, territorial animal that lives in freshwater rivers and lakes, as long as there’s plenty of cover around the edges for it to hide. A big male can grow up to 4.5 feet long, or 1.4 meters, although most are much smaller and females are smaller overall than males. It’s dark brown with a lighter belly, and has a long, slender body, short legs with webbed toes, and a small flattened head with tiny ears. Its tail is thick and tapering. It mostly eats fish, frogs, and various invertebrates like crayfish.

Tapper’s sighting is especially interesting because of the trail of bubbles he reported. This is sometimes called a bubble chain and is a telltale sign that an otter is swimming underwater.

But there’s no evidence, fossil or otherwise, that otters ever lived in New Zealand, or Australia either for that matter. Some species of otter do live in South Asia, but that’s still a long, long way from New Zealand. One theory is that domesticated otters kept as fishing animals were brought to New Zealand by South Asian fishermen who were either lost or blown away from their homes by storms. The problem with this theory is not just that there’s no evidence for it among Maori oral histories, it’s that the fishermen would have had to somehow avoid Australia completely even though it’s a humongous continent they would have to go around to reach New Zealand’s South Island.

There is an unrelated animal in parts of Australia that looks a lot like a small otter, though. That’s the rakali, or water-rat, a semi-aquatic rodent native to Australia, New Guinea, and some nearby islands.

The rakali grows up to about 15 inches long, or 39 cm, not counting its long tail. It has black or dark gray fur with a paler belly, but its tail has a white tip. It has short legs, a small flattened head with small rounded ears, webbed toes on its hind feet, and while its tail is thick for a rodent, it’s thin compared to an otter’s tail. It eats many of the same things that otters eat and is especially good at killing the cane toad, a toxic invasive species in parts of Australia.

But the rakali has never been introduced to New Zealand and has never been seen there. While it does superficially resemble a small otter, it acts very rodent-like in many ways. For instance, it sits up on its haunches to eat and when it’s doing that, it doesn’t look anything like an otter, although it is really cute. It also marks its territory with a scent that smells strongly like cat urine.

Stoats and weasels have been introduced to New Zealand, where they’re invasive species. While they’re much smaller than otters, they do have a similar body shape and both can swim well when they want to. It’s possible that at least some waitoreke sightings are actually sightings of swimming stoats or weasels, although that doesn’t explain all the reports by any means.

Another theory is that the waitoreke isn’t an otter at all but a rare, unknown mammal native to New Zealand. Since New Zealand’s only native land mammals are bats, until 2006 researchers generally rejected this theory out of hand. That’s because until 2006, there weren’t even any fossil remains of mammals found on New Zealand.

New Zealand is just a small part of an otherwise submerged continent called Zealandia. Zealandia was once part of the supercontinent Gondwana, smooshed up next to what are now Australia and Antarctica. Zealandia separated from its neighbors around 80 million years ago and started slowly sinking into the ocean. Then, about 66 million years ago, the massive asteroid strike we talked about in episode 240 killed off the non-avian dinosaurs.

Afterwards, in most of the world, mammals began to evolve rapidly to fill the vacant ecological niches. But Zealandia didn’t have very many mammals to start with, and by 25 million years ago it was mostly underwater anyway except for the highest mountain peaks that stuck up as islands. At this point, though, the continental plate had stopped sinking and instead was being pushed up slowly by tectonic forces—a process that’s still ongoing.

For a long time, geologists even thought Zealandia might have been completely underwater. It wasn’t surprising that the only animals living on land were birds and bats, since they could have flown there after the land re-emerged. But even as evidence of those mountaintop islands became understood, mammals were still nonexistent in New Zealand’s fossil history.

Then, in 1978, some small, incomplete fossils were discovered near Saint Bathans in the southern part of the South Island. This is a rich area for fossils that date to around 16 to 19 million years ago. There are remains of fish, reptiles, a few bats, and lots of birds, and in 2006, paleontologists studying those fossils found in 1978 announced that they’d identified them as the remains of a terrestrial mammal.

It’s referred to as the Saint Bathans mammal and we know almost nothing about it. We only have two fragments of a lower jaw and one femur. We’re pretty sure it’s not a monotreme but that’s about as far as it goes. It was probably the size of a mouse.

Because Zealandia has been separated from all other landmasses for about 80 million years, the Saint Bathans mammal that lived around 17 million years ago was probably very different from mammals found in other parts of the world. Its descendants probably went extinct in the middle Miocene, around 14 million years ago, when there was a relatively small extinction event throughout the world related to a long period of global cooling. But some people theorize that descendants of the Saint Bathans mammal survived to the present day, a rare and shy semi-aquatic animal that fills the same ecological niche as otters and has evolved to look like otters due to convergent evolution.

It’s not likely, to be honest. It’s even less likely than the theory about lost fishermen with pet otters drifting thousands of miles around Australia to come ashore on New Zealand, and that’s not very likely either.

There are still occasional sightings of the waitoreke. With luck someone will get some good pictures of one soon so we can learn more about what this mysterious animal might be.

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

Thanks for listening!

Episode 271: Springtime Animals

Pre-order your tiny pin friend via our Indiegogo campaign!

This week we talk about some springtime animals! Sort of! Thanks to Derek and Nikita for their suggestions!

Happy birthday to Lillian, Hannah, and Derek! What a busy birthday week! Everybody gets cake!

Further reading:

Tales from Tennessee

There’s more than one way to grow a beak

A male river chub. “It’s not funny guys, put me down guys” (photo by Bill Hubick):

Busy busy busy building a big big nest (photo from site linked to above):

Got a rock (photo from site linked to above):

One bilby:

Two bilbies:

Easter bilbies not bunnies:

Egg tooth:

The red jungle fowl is the wild ancestor of the domestic chicken:

Modern domestic chickens:

Show transcript:

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

It’s springtime in the northern hemisphere, with spring festivals like Easter coming up fast. This week let’s look at three animals that represent springtime, sort of. Thanks to Derek and Nikita for suggesting two of the animals we’ll learn about this week!

Before we start, though, two things! One, I’m running a little crowdfunding campaign to have some enamel pins made. I won’t spam you about it like our big Kickstarter for the book last fall, but there will be a link in the show notes if you want to take a look. There are three designs, a narwhal, a capybara with a tangerine on its head, and a not-terribly-accurate thylacine. The campaign is called Tiny Pin Friends and it’s on Indiegogo.

https://www.indiegogo.com/projects/tiny-pin-friends/x/2964999#/

Two, it’s birthday shout-out time! This week we have not one, not two, but THREE birthday shout-outs! You know what that means, of course. It means we all need to be celebrating all week! A great big happy birthday to Lillian, Hannah, and Derek! And yes, birthday Derek is the same Derek who suggested one of the animals this week!

In fact, let’s start with his suggestion, a fish called the river chub. It’s a little fish that only grows a little over a foot long at most, or 33 cm, although it’s usually much smaller than that. It’s common in fast-moving streams and rivers throughout North America, especially in the Appalachian Mountains and surrounding areas.

The river chub isn’t all that exciting to look at, unless of course you’re a fish enthusiast or a river chub yourself. It’s greenish-silver above and pale underneath with orange fins. Males are larger than females and during breeding season, in late spring, the male turns purplish-red, his head enlarges, and he develops tubercles on the front part of his head that look sort of like white rhinestones.

His physical changes aren’t just to attract a mate. The male river chub builds a pebble nest by picking up little stones and moving them to just the right spots, so by having a more robust head and broad mouth, he can pick up bigger stones. And he picks up a LOT of stones, as many as 10,000 of them, which he arranges and rearranges.

Females are attracted to well-made nests. After a female lays her eggs in the nest, the male fertilizes the eggs and then spends the next week or so defending them by head-butting other males and potential predators, until the eggs hatch into larvae.

The pebble nests help other animals too. Over 30 species of fish use the nests as spawning sites once the river chub’s eggs hatch. Good job, river chub, helping out all those other fish!

Next, a while back Nikita suggested we learn about the bilby. It’s not springtime right now in Australia where the bilby lives, but the Christian holiday of Easter is still celebrated at the same time as it is in the northern hemisphere. Instead of chocolate Easter bunnies, in Australia they also have chocolate Easter bilbies.

In 1968, a nine-year-old girl named Rose-Marie Dusting wrote a story called “Billy the Aussie Easter Bilby.” When she grew up, Rose-Marie published the story as a picture book, which became popular enough that it inspired people in Australia to start talking about the Easter bilby instead of the Easter bunny. Starting in 1991 there was a big push to change from Easter bunnies to bilbies. Rabbits are an invasive species in Australia and do a lot of damage, and in fact they’ve almost driven the bilby to extinction. The lesser bilby did go extinct in the 1950s but the greater bilby is hanging on despite introduced predators like cats and foxes, rabbits and other introduced animals that eat all their food, and habitat loss.

The bilby has silky fur that’s mostly gray in color, and it has long pink ears that look sort of like a rabbit’s. It’s sometimes called the rabbit-eared bandicoot because of its ears. It has a long, pointy muzzle that’s pink and a long tail that’s black with a white tip, and it’s about the size of a cat but with shorter, thinner legs. It has a good sense of smell and good hearing, naturally, but its big ears are also useful for shedding heat. This is important since it often lives in hot, dry areas.

The bilby is nocturnal and spends the day in one of several burrows it digs in its territory. Not only are the burrows up to almost 10 feet long, or 3 meters, but they can be up to 6 feet deep, or 2 meters, with multiple exits. Digging such large, deep burrows not only keeps the bilby cool on hot days, it helps improve soil quality and provides shelter for lots of other animals that move in when the bilby isn’t home.

The bilby eats a lot of plant material, including seeds, fruit, bulbs, and tubers, along with eggs and various types of fungus, but it also eats insects, spiders, grubs, snails, and other small animals. It gets all of the moisture it needs from its diet. Its tongue is long and sticky, which helps it gather termites and other insects more easily, and its ears are so sensitive that it can hear insects moving around underground. It will actually put its ear to the ground to listen, then dig the insect up.

A mother bilby usually has one or two babies at a time that stay in her pouch for a little under three months. Her pouch is rear-facing so that sand and dirt don’t get onto her joeys when she digs a new burrow. Once her joey leaves the pouch, she hides it in one of her burrows and comes to feed and take care of it for another few weeks, until it’s ready to strike out on its own. In a lot of marsupials, the joey will come and go from the pouch as it grows older, but by the time the bilby’s joey is ready to emerge from the pouch, she already has a new baby or two ready to be born, so she needs her pouch for the new joeys.

Sales of some brands of chocolate Easter bilbies raise money to help bilby conservation efforts. And here I thought there was no way to improve on chocolate.

We’ll finish with the humble domestic chicken. Chickens are symbols of springtime because that’s when they start laying a whole lot of eggs. Most birds only lay eggs after mating, but chickens have been selectively bred so that the females, called hens, start to lay unfertilized eggs once they’re adults. The eggs you buy at the grocery store are unfertilized. Some people think those little whitish strings on either side of the yolk are embryonic baby chicks, but that’s not the case. Those strings are called chalazae [ka-LAYzee] and they help keep the yolk from moving around too much inside the egg.

Modern domestic chickens are descendants of wild birds called jungle fowl that evolved in parts of Southeast Asia some 50 million years ago. Humans domesticated the red jungle fowl at least 8,000 years ago, probably independently in different areas, and they’ve spread around the world as people migrated from place to place. The red jungle fowl is still around in the wild, too. It looks like a chicken.

Like all birds, jungle fowl descended ultimately from theropod dinosaurs. This included Tyrannosaurus rex, which means you’ll occasionally hear people say that chickens are direct descendants of T. rex. While chickens and other birds are related to T. rex, you wouldn’t find a T. rex in a chicken’s direct ancestry even if you could follow it back 66 million years, although you would find much smaller theropods. You’d have to go back farther than 66 million years, though, because paleontologists think theropods started evolving bird-like features some 160 million years ago.

You may have heard the saying, “That’s as scarce as hen’s teeth” to indicate something that’s not just rare, it’s basically non-existent. That’s because chickens, like all modern birds, don’t have teeth. Most birds and reptiles do grow what’s called an egg tooth, which actually looks like a little spike at the tip of the bill, or the nose in reptiles. It helps the baby break out of its egg, after which it either falls off or is reabsorbed. But it’s not a real tooth.

In late 2020 paleontologists announced they’d found a fossil skull on the island of Madagascar, dated to 85 million years ago, that shows an animal with a beak. The animal resembles a small theropod dinosaur in some ways and resembles an early bird in other ways, but it has features never before seen in either. Its snout is elongated but deep with a heavy bill that looks a little like a toucan’s bill. The bill doesn’t have teeth along the jaws, although other early birds found from around the same time do. That means that not only did birds stop needing teeth as early as 85 million years ago, toothlessness must have evolved repeatedly in various species. However, the new animal’s beak does have teeth at the very tip of its mouth.

Recent research suggests that birds and their ancestors evolved toothless beaks instead of toothy snouts because they had such specialized diets. There were probably also other benefits to having beaks instead of teeth. Some research suggests it might have helped speed up egg hatching. Other studies suggest the lack of teeth lightened the bird’s head and improved flight.

Occasionally a chicken embryo bears a recessive trait called talpid. It’s a lethal mutation, but talpid chick embryos do sometimes live in the egg for a couple of weeks before dying. Genetic researchers study talpid chickens for various reasons, and at one point a researcher named Matthew Harris noticed something odd on the beak of a talpid chicken embryo. It had tiny bumps along the edge that looked like teeth.

Harris took his findings to biologist John Fallon, who verified that the structures are actually teeth, not just serrations. They develop from the same tissues that form teeth in mammals, but the teeth don’t resemble mammal teeth. Instead they’re conical and pointy like a dinosaur’s teeth.

Harris eventually engineered a virus that mimicked the mutation’s molecular signals. Introducing the virus into chickens without the talpid mutations resulted in the chickens developing teeth, although they were reabsorbed into the beak after developing.

So I guess hen’s teeth are still as scarce as hen’s teeth. Also, I don’t really know how we made it here from springtime animals, but here we are.

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

Thanks for listening!

Episode 270: The Tapir Frog

New frog just dropped.

Happy birthday to Finn and Oran this week! Have a great birthday, both of you!

Further reading:

Frog with tapir-like nose found in Amazon rainforest, thanks to its “beeping” call

Meet the tapir frog:

Looks kind of like the South American tapir, but frog:

Show transcript:

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

This week we have a short episode about the recent discovery of a mystery frog in Peru–but first, we have TWO birthday shout-outs! That’s twice the fun!

Happy birthday to both Finn and Oran! I hope your birthdays are amazing! Maybe you should each have two birthday parties, one for yourself and one for the other, even though you don’t know each other and your birthdays are actually on different days.

Peru is a country in western South America, and it’s home to the Amazon Basin rainforest and many other habitats. Frogs are common throughout the Amazon, naturally, since there’s a whole lot of water and rain, and it’s warm all the time. One particular genus of frog, Synapturanus, is especially widespread but is hard to find because it spends most of its time underground.

A team of scientists researching the Amazon’s diversity of animals and plants, especially those organisms that are mostly hidden for various reasons, heard about a particular Synapturanus frog known to the people of the area. The frog is nocturnal and lives underground in burrows it digs in the Amazon peatlands.

Peat is wet soil made up mostly of partially decayed vegetation. It’s the first step in the formation of coal beds, but the coal takes millions of years to form whereas peat only take thousands of years to form. Peatlands are really important to the ecological health of the entire earth, because they store so much carbon and absorb so much water.

The scientists knew from locals that this particular frog existed. The next step was to actually find it so they could learn more about it. A small team of scientists from Peru and other countries traveled to the area, and local guides took them to sites where the frog was supposed to live.

Because the frog is nocturnal, they had to go at night to find it. But because the frog also spends most of its time underground, they couldn’t just walk around shining flashlights on frog-shaped things in hopes of finding a new species of frog. Instead, they had to listen.

Many new frog species are only discovered after a frog expert hears a call they don’t recognize. That was the case for this frog. The male makes a loud beeping noise, especially after rain. Whenever one of the scientists heard one, they’d immediately drop to the ground and start digging with their hands. I can’t even imagine how muddy they must have gotten.

It was around 2am on the last night of the search when their digging paid off. A little brown frog hopped out of its disturbed burrow and all the scientists scrambled around in an excited panic to catch it carefully before it got away.

This is what the frog sounds like:

[tapir frog beeping]

The locals call the frog rana danta, which means tapir frog. The tapir, as you may remember from episodes 18 and 245, among others, is a sort of pig-shaped animal with a short trunk-like snoot called a proboscis. It’s distantly related to rhinoceroses and horses. It uses its proboscis to gather plants and spends a lot of time underwater, and will even sink to the bottom of a pond or stream and walk across it on the bottom instead of swimming.

The tapir most common around the Amazon in Peru is the South American tapir. It’s dark brown in color with a tiny little stub of a tail and a shorter proboscis than other tapir species. Its proboscis looks less like a little trunk and more like a long pointy nose.

The tapir frog is chocolate brown in color, has no tail of course because it’s a frog, and while it has a chonky body sort of life a tapir, its nose draws out to a blunt point. It looks remarkably similar in shape to a South American tapir, but in frog form.

The team ended up catching several of the frogs, and genetic studies determined that it is indeed a new species. They described the new frog in February of 2022 and named it Synapturanus danta. Danta is the local word for tapir.

While we still don’t know much about the tapir frog, it probably lives only in the Amazon peatlands and eats worms and small insects it finds underground. The discovery is important because it’s yet another animal endemic to this part of the Amazon. Conservationists are working to preserve the Amazon peatlands habitat from development in order to save all the unique plants and animals that live there. Development is just a fancy term for habitat loss.

The Putumayo Corridor is a proposed conservation area that follows the Putumayo River across Ecuador, Colombia, Peru, and Brazil. Its goal is to keep the river from being dammed and protect it from logging and other invasive development, while allowing local people to manage the land in traditional ways as they have for thousands of years. Hopefully the peatlands will remain undisturbed and the little tapir frog will continue to beep from its underground home for a very long time.

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

Thanks for listening!

Episode 269: Gila Monsters, Basilisks, and Sand Boas, oh my!

Thanks to Zachary, Enzo, and Oran for their suggestions this week! Let’s learn about some interesting reptiles!

Happy birthday to Vale! Have a fantastic birthday!!

The magnificent Gila monster:

The Gila monster’s tongue is forked, but not like a snake’s:

The remarkable green basilisk (photo by Ryan Chermel, found at this site):

A striped basilisk has a racing stripe:

I took this photo of a basilisk myself! That’s why it’s a terrible photo! The basilisk is sitting on a branch just above the water, its long tail hanging down:

The desert sand boa:

Show transcript:

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

This week we’re going to learn about three weird and interesting reptiles, with suggestions from Zachary, Enzo, and Oran, including a possible solution to a mystery animal we’ve talked about before!

But first, we have a birthday shoutout! A very happy birthday to Vale! You should probably get anything you want on your birthday, you know? Want a puppy? Sure, it’s your birthday! Want 12 puppies? Okay, birthday! Want to take your 12 puppies on a roadtrip in a fancy racecar? Birthday!

Our first suggestion is from Enzo and Zachary, who both wrote me at different times suggesting an episode about the Gila monster. How I haven’t already covered an animal that has monster right there in its name, I just don’t know.

The Gila monster is a lizard that lives in parts of southwestern North America, in both the United States and Mexico. It can grow up to two feet long, or 60 cm, including its tail. It’s a chonky, slow-moving lizard with osteoderms embedded in its skin that look like little pearls. Only its belly doesn’t have osteoderms. This gives it a beaded appearance, and in fact the four other species in its genus are called beaded lizards. Its tongue is dark blue-black and forks at the tip, but not like a snake’s tongue. It’s more like a long lizard tongue that’s divided at the very end.

The Gila monster varies in color with an attractive pattern of light-colored blotches on a darker background. The background color is dark brown or black, while the lighter color varies from individual to individual, from pink to yellow to orange to red. You may remember what it means when an animal has bright markings that make it stand out. It warns other animals away. That’s right: the Gila monster is venomous!

The Gila monster has modified salivary glands in its lower jaw that contain toxins. Its lower teeth have grooves, and when the lizard needs to inject venom, the venom flows upward through the grooves by capillary force. Since it mostly eats eggs and small animals, scientists think it only uses its venom as a defense. Its venom is surprisingly toxic, although its bite isn’t deadly to healthy adult humans. It is incredibly painful, though. Some people think the Gila monster can spit venom like some species of cobra can, but while this isn’t the case, one thing the Gila monster does do is bite and hold on. It can be really hard to get it to let go.

The fossilized remains of a Gila monster relative were discovered in 2007 in Germany, dating to 47 million years ago. The fossils are well preserved and the lizard’s teeth already show evidence of venom canals. The Gila monster is related to monitor lizards, although not closely, and for a long time people thought it was almost the only venomous reptile in the world. These days we know that a whole lot of lizards produce venom, including the Komodo dragon, which is a type of huge monitor lizard.

In 2005, a drug based on a protein found in Gila monster venom was approved for use in humans. It helps manage type 2 diabetes, and while the drug itself is synthetic and not an exact match for the toxin protein, if researchers hadn’t started by studying the toxin, they wouldn’t have come up with the drug.

The Gila monster lives in dry areas with lots of brush and rocks where it can hide. It spends most of its time in a burrow or rock shelter where it’s cooler and the air is relatively moist, and only comes out when it’s hungry or after rain. It eats small animals of various kinds, including insects, frogs, small snakes, mice, and birds, and it will also eat carrion. It especially likes eggs and isn’t picky if the eggs are from birds, snakes, tortoises, or other reptiles. It has a keen sense of smell that helps it find food. During spring and early summer, males wrestle each other to compete for the attention of females. The female lays her eggs in a shallow hole and covers them over with dirt, and the warmth of the sun incubates them.

The Gila monster is increasingly threatened by habitat loss. Moving a Gila monster from a yard or pasture and taking it somewhere else actually doesn’t do any good, because the lizard will just make its way back to its original territory. This is hard on the lizard, because it requires a lot of energy and exposes it to predators and other dangers like cars. It’s better to let it stay where it is. It eats animals like mice and snakes that you probably would rather not have in your yard anyway, and as long as you don’t bother it, it won’t bother you. Also, it’s really pretty.

Next, Oran wants to learn more about the basilisk lizard. We talked about it very briefly in episode 252 and I actually saw two of them in Belize, so they definitely deserve more attention.

The basilisk lives in rainforests from southern Mexico to northern South America. There are four species, and a big male can grow up to three feet long, or 92 cm, including his long tail. The basilisk’s tail is extremely long, in fact—up to 70% of its total length.

Both male and female basilisks have a crest on the back of the head. The male also has a serrated crest on his back and another on his tail that make him look a little bit like a tiny Dimetrodon.

The basilisk is famous for its ability to run across water on its hind legs. The toes on its large hind feet have fringes of skin that give the foot more surface area and trap air bubbles, which is important since its feet plunge down into the water almost as deep as the leg is long. Without the air trapped under its toe fringes, it wouldn’t be running, it would be swimming. It can run about 5 feet per second, or 1.5 meters per second, for about three seconds, depending on its weight. It uses its long tail for balance while it runs.

When a predator chases a basilisk, it rears up on its hind legs and runs toward the nearest water, and when it comes to the water it just keeps on running. The larger and heavier the basilisk is, the sooner it will sink, but it’s also a very good swimmer. If it’s still being pursued in the water, it will swim to the nearest tree and climb it, because it also happens to be a really good climber.

The basilisk can also close its nostrils to keep water and sand out, which is useful because it sometimes burrows into sand to hide. It can also stay underwater for as long as 20 minutes, according to some reports. It will eat pretty much anything it can find, including insects, eggs, small animals like fish and snakes, and plant material, including flowers. It mostly eats insects, though.

Fossil remains of a lizard discovered in Wyoming in 2015 may be an ancestor to modern basilisks. It lived 48 million years ago and probably spent most of its time in trees. It had a bony ridge over its eyes that shaded its eyes from the sun and also made it look angry all the time. It grew about two feet long, or 61 cm., and may have already developed the ability to run on its hind legs. We don’t know if it could run on water, though.

Finally, Zachary also suggested the sand boa. Sand boas are non-venomous snakes that are mostly nocturnal. During the day the sand boa burrows deep enough into sand and dirt that it reaches a cool, relatively moist place to rest. At night it comes out and hunts small animals like rodents. If it feels threatened, it will dig its way into loose soil to hide. It’s a constrictor snake like its giant cousin Boa constrictor, but it’s much smaller and isn’t aggressive toward humans.

Zachary thinks that the sand boa might actually be the animal behind sightings of the Mongolian death worm. We’ve talked about the Mongolian death worm in a few episodes, most recently in episode 156.

The Mongolian death worm was first mentioned in English in a 1926 book about paleontology, but it’s been a legend in Mongolia for a long time. It’s supposed to look like a giant sausage or a cow’s intestine, reddish in color and said to be up to 5 feet long, or 1.5 meters. It mostly lives underground in the western or southern Gobi Desert, but in June and July it surfaces after rain. Anyone who touches the worm is supposed to die painfully, although no one’s sure how exactly it kills people. Some suggestions are that it emits an electric shock or that it spits venom.

Mongolia is in central Asia and is a huge but sparsely populated country. At least one species of sand boa lives in Mongolia, although it’s rare. This is Eryx miliaris, the desert sand boa. Females can grow up to 4 feet long, or 1.2 meters, while males are usually less than half that length. Until recently it was thought to be two separate species, and sometimes you’ll see it called E. tataricus, but that’s now an invalid name.

The desert sand boa is a strong, thick snake with a blunt tail and a head that’s similarly blunt. In other words, like the Mongolian death worm it can be hard to tell at a glance which end is which. Its eyes are small and not very noticeable, just like the death worm. It’s mostly brown in color with some darker and lighter markings, although its pattern can be quite variable. Some individuals have rusty red markings on the neck.

It prefers dry grasslands and will hide in rodent burrows. When it feels threatened, it will coil its tail up and may pretend to bite, but like other sand boas it’s not venomous and is harmless to humans.

At first glance, the desert sand boa doesn’t seem like a very good match with the Mongolian death worm. But in 1983, a group of scientists went searching for the death worm in the Gobi. They were led by a Bulgarian zoologist named Yuri Konstantinovich Gorelov, who had been the primary caretaker of a nature preserve in Mongolia for decades and was familiar with the local animals. The group visited an old herder who had once killed a death worm, and in one of those weird coincidences, while they were talking to the herder, two boys rushed in to say they’d seen a death worm on a nearby hill.

Naturally, Gorelov hurried to the top of the hill, where he found a rodent burrow. Remember that this guy knew every animal that lived in the area, so he had a good idea of what he’d find in the burrow. He stuck his hand into it, which made the boys run off in terror, and pulled out a good-sized sand boa. He draped it around his neck and sauntered back to show it to the old herder, who said that yes, this was exactly the same kind of animal he’d killed years before.

That doesn’t mean every sighting of a death worm is necessarily a sand boa. I know I’ve said this a million times, but people see what they expect to see. The death worm is a creature of folklore, whether or not it’s based on a real animal. If you hear the story of a dangerous animal that looks like a big reddish worm with no eyes and a head and tail that are hard to distinguish, and you then see a big snake with reddish markings, tiny eyes, and a head and tail that are hard to distinguish, naturally you’ll assume it’s a death worm.

At least some sightings of the death worm are actually sightings of a sand boa. But some death worm sightings might be due to a different type of snake or lizard, or some other animal—maybe even something completely new to science. That’s why it’s important to keep an open mind, even if you’re pretty sure the animal in question is a sand boa. Also, maybe don’t put your bare hand in a rodent burrow.

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

Thanks for listening!