Category Archives: South America

Episode 377: The Giant-est Snake Ever

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Thanks to Max for suggesting Titanoboa!

Further reading:

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

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

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

Titanoboa had really big bones compared to its modern relatives:

Vasuki had big bones too:

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Thanks for listening!

Episode 375: The Praying Mantis Re-Revisited

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Thanks to Elijah and an anonymous listener for suggesting that we talk about some more species of praying mantis!

Further reading:

The luring mantid: Protrusible pheromone glands in Stenophylla lobivertex (Mantodea: Acanthopidae)

Dragons and unicorns (mantises) spotted in Atlantic forest

Citizen scientists help discover new mantis species

The dragon mantis [photo from first article linked above]:

The possibly new species of unicorn mantis [picture from second article linked above]:

Inimia nat, or I. nat, discovered after a citizen scientist posted its photo to iNat [photo from third article linked above]:

Show transcript:

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

This week we’re going to revisit a popular topic that we’ve covered before, especially in episode 187, but which has been suggested by a couple of listeners who want to know more. It’s the praying mantis. Thanks to Elijah and an anonymous listener who suggested it. Elijah even keeps mantises as pets and sent me some pictures of them, which was awesome.

The praying mantis gets its name because it holds its spiny front legs forward and together, which sort of resembles someone holding their hands together while praying. That’s the type of praying spelled p r a y ing, not p r e y ing, which refers to killing and eating other organisms, but the praying mantis does that too. It’s a predator that will eat anything it can catch, including birds, fish, mice, lizards, frogs, and of course lots of insects.

There are thousands of mantises, also called mantids, with most species preferring tropical and subtropical climates. In general, a mantis has a triangular head with large eyes, an elongated body, and enlarged front legs that it uses to catch prey. Most species have wings and can fly, some don’t. Most are ambush predators.

We talked about several species of mantis in episode 187, and some more in episode 201. You can go back to those episodes to find out general information about mantises, such as how their eyes work and whether they have ears and whether they actually eat their mates (they do, sometimes). This week we’re going to focus on some findings about mantises that are new since those episodes came out.

The dragon mantis, Stenophylla lobivertex, was only discovered in the year 2000. Its body is covered with gray-green or green-brown lobes that help it blend in with the leaves in its forest home, but that also kind of make it look like a tiny dragon covered with scaly armor. Even its eyes are spiky. It lives in the tropics of South and Central America where it’s quite rare, and it usually only grows about an inch and a half long, or 4 cm. It spends most of the time in treetops, where it hunts insects, spiders, and other small animals.

Unlike many mantis species, the dragon mantis is mostly nocturnal. That’s one of the reasons why we don’t know a lot about it. In late 2017 through mid-2018, one member of a team of scientists studying animals in Peru noticed something weird in a captive female dragon mantis. Frank Glaw isn’t an expert in insects but in reptiles and amphibians, but he happened to observe what looked like two tiny maggots emerge from the mantis’s back, roughly above her last pair of legs, but then disappear again into her back. He thought he was seeing the results of parasitism, but a mantis expert suspected it was something very different.

Some praying mantis females release pheromones from a gland in about the same place on the back. Pheromones are chemicals that can be sensed by other insects, usually ones in the same species. They’re most often used to attract a mate. It turns out that the female dragon mantis has a Y-shaped organ that’s up to 6 mm long that can release pheromones in a particular direction. The mantis can even move the prongs of the Y around if she wants to. Because she only does this at night when she’s sure she’s safe, and only when she hasn’t found a mate yet, and because this species of mantis is really rare, no one knew that any mantis had this specific organ. It’s possible that other mantis species have the organ too, but that scientists just haven’t seen it yet.

As we learned in our previous mantis episodes, not only are there well over 2,000 known species of mantis alive today, there are more being discovered all the time. In 2019, Project Mantis went to Brazil to look for mantises, and not only did they find two of the extremely rare dragon mantises, they discovered what may be a species new to science. It hasn’t been described yet as far as I can find, but it appears to be a member of a group called unicorn mantises because it has a spike sticking up from the top of the head. Scientists have no idea what the spike is for, but it’s funny that they found unicorn mantises and dragon mantises in the same forest.

Late in 2023, two new species of Australian mantis were described, one of which is so different from other known species that it was placed in its own genus. They’re small mantises that live on tree trunks and are camouflaged to look like pieces of bark, so they’re hard to spot. Luckily, a citizen scientist named Glenda Walter noticed them and posted pictures to iNaturalist. A lot of scientists watch iNaturalist posts, and it’s a good thing because Glenda’s mantises turned out to be completely new to science. One of them has been named Inimia nat, which is abbreviated I. nat, which is also the abbreviation for iNaturalist. A citizen scientist is anyone who is interested in science and works to help improve scientific knowledge in general, for instance by taking pictures of interesting bugs and posting them to iNat.

The praying mantis has been around since at least the early Cretaceous, around 120 million years ago. The oldest remains found don’t look that much like modern mantises, though. They look more like cockroaches, which isn’t too surprising since mantises are closely related to cockroaches. By about 110 million years ago mantises had started to evolve the deadly front legs that they have now. Most fossilized mantis remains are actually impressions of wings, but experts can learn a lot from just the wings. Baby praying mantises have even been found preserved in amber from up to 87 million years ago.

A lot of people are scared of praying mantises because they look dangerous. They’re not dangerous to humans or pets at all, though. If you get pinched or nipped by a mantis, just wash your hands to clean out the wound and you’ll be fine. Mantises are extremely beneficial insects, especially in the garden, because they eat other insects that eat plants that humans don’t want eaten, like flowers and vegetables. Some people release mantises in the garden as a natural way to control insect pests. And, as Elijah can tell you, mantises actually make really interesting pets.

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

Thanks for listening!

Episode 365: A New Temnospondyl

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Let’s take a look at some new findings about the temnospondyls this week!

Further reading:

Ancient giant amphibians swam like crocodiles 250 million years ago

Fossil of Giant Triassic Amphibian Unearthed in Brazil

Kwatisuchus rosai was an early amphibian [picture taken from article linked above]:

Koolasuchus was a weird big-headed boi:

Show transcript:

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

This week we’re going to revisit an animal we talked about way back in episode 172, the temnospondyl. That’s because a new species of temnospondyl has been named that lived about 250 million years ago, and some other new information has been published about temnospondyls in general.

In case you haven’t listened to episode 172 in a while, let’s brush up on some history. The temnospondyls arose about 330 million years ago during the Carboniferous period. Ocean levels were high, the continents were coming together slowly to form the supercontinent Pangaea, and much of the land was flooded with warm, shallow water that created enormous swampy areas full of plants. Naturally, a whole lot of animals evolved to live in the swamps, and the temnospondyls were especially successful.

Temnospondyls were semi-aquatic animals that probably looked a lot like really big, really weird salamanders. This was before modern amphibians evolved, and scientists still aren’t sure if the temnospondyls are the direct ancestors of modern amphibians or just cousins that died out with no living descendants. Temnospondyls do share many traits with modern amphibians, but they still had a lot in common with their fish ancestors.

Most temnospondyls had large heads that were broad and flattened in shape, often with a skull that was roughly triangular. Some had smooth skin but many had scales, including some species with scales that grew into armor-like plates. The earliest species had relatively small, weak legs and probably spent most of their time in the water, but it wasn’t long before species with stronger legs developed that probably lived mostly on land.

Many temnospondyls were small, but some grew really big. The biggest found so far is Prionosuchus, which is only known from fragmentary specimens discovered in Brazil in South America. It had an elongated snout something like a ghavial’s, which is a type of crocodilian that mostly eats fish, and a similar body shape. That’s why its name ends in the word “suchus,” which refers to a crocodile or an animal that resembles a crocodilian. Inside, though, prionosuchus probably had more in common with its fish ancestors than with modern crocodiles, and of course it wasn’t a reptile at all. It was an amphibian, possibly the largest one that’s ever lived. The biggest specimen found so far had a skull that measured just over 5 feet long, or 1.6 meters. That was just the skull! The whole animal, tail and all, might have measured as much as 30 feet long, or about 9 meters, although most paleontologists think it was probably more like 18 feet long, or 5-1/2 meters. That’s still incredibly big, as large as the average saltwater crocodile that lives today.

The resemblance of many temnospondyls to crocodilians is due to convergent evolution, since researchers think a lot of temnospondyls filled the same ecological niche as modern crocodiles. If you’re an ambush predator who spends a lot of time hiding in shallow water waiting for prey to get close enough, the best shape to have is a long body, short legs, a long tail that’s flattened side to side to help you swim, and a big mouth for grabbing, preferably with a lot of teeth. A study published in March of 2023 examined some trace fossils found in South Africa that scientists think were made about 255 million years ago by a temnospondyl. The fossils were found in what had once been a tidal flat or lagoon along the shore of the ancient Karoo Sea. You didn’t need to know it was called the Karoo Sea but I wanted to say it because it sounds like something from a fantasy novel. Truly, we live in a wonderful world. Anyway, there aren’t very many footprints but there are swirly marks made by a long tail and body impressions where the animal settled onto the floor to rest.

From those trace fossils, scientists can learn a lot about how the animal lived and moved. The swirly tail marks show that it used it tail to swim, not its legs. Since there are hardly any footprints, it probably kept its legs folded back against its body while it was swimming. When it stopped to rest, it may have been watching for potential prey approaching from above, since its eyes were situated on the top of its head to allow it to see upward easily. All these traits are also seen in crocodiles even though temnospondyls aren’t related to crocodilians at all.

Other big temnospondyls that filled the same ecological niche as crocodiles were species in the family Benthosuchidae. Some grew over 8 feet long, or 2.5 meters. That may not seem very big compared to a dinosaur or a whale, but this is your reminder that it was an early amphibian, and that amphibians are usually little guys, like frogs and newts.

The newly discovered fossil I mentioned at the beginning of this episode has been identified as a member of the family Benthosuchidae. It’s been named Kwatisuchus rosai and was discovered in Brazil in 2022. That’s a big deal, because while temnospondyl fossils have been found throughout the world, until Kwatisuchus, benthosuchids have only been found in eastern Europe. It was five feet long, or 1.5 meters, and it was probably an ambush predator that mostly ate fish.

Kwatisuchus lived only a few million years after the end-Permian extinction event, also called the Great Dying, which we talked about in episode 227. That extinction event wiped out entire orders of animals and plants. Temnospondyls in general survived the Great Dying and hung on for another 100 million years afterwards.

The last temnospondyl that lived, as far as the fossil record shows, was Koolasuchus. It lived in what is now Australia and went extinct about 120 million years ago. This is a lot more recent than most temnospondyls, so much so that when it was first discovered, scientists at first didn’t think it could be a temnospondyl. It was only described in 1997, although it was first discovered in 1978.

Not only was Koolasuchus the most recently living temnospondyl, it was also big and heavy and very weird-looking. It was about 10 feet long, or about 3 meters, and might have weighed as much as 1,100 lbs, or 500 kg. It lived in fast-moving streams and filled the same ecological niche as crocodiles, which eventually replaced it after it went extinct.

Like its relations, Koolasuchus had a roughly crocodile-shaped body with short legs and a fairly long tail, but its head was almost as big as its body. Most temnospondyls had big heads, and Koolasuchus’s was broad and rounded with a blunt nose. It also had what are called tabular horns that projected from the rear of the skull, which gave its head a triangular appearance. Its body was relatively slender compared to the chonky head, which made it look kind of like a really really big tadpole.

Remember, as an amphibian, Koolasuchus would have laid eggs that hatched into a larval form the same way frogs do today. We have a lot of larval temnospondyl fossils and even some fossilized eggs that paleontologists think were laid by a temnospondyl, which were attached to water plants the same way many species of frog do today. Larval temnospondyls did look a lot like tadpoles. In other words, Koolasuchus looked like a tadpole in shape but its larval form was also probably tadpole-like. Extra, extra tadpole-shaped.

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

Thanks for listening!

Episode 358: The Bush Dog and the Maned Wolf

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Thanks to Dean, Mia, and Lydia for their suggestions this week!

The tayra looks kind of like a canid but is a mustelid [photo by Bob Johnson – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=85291909]:

The bush dog looks kind of like a mustelid but is a canid:

The maned wolf looks like a fox with reallllllly long legs:

Show transcript:

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

This week we have a suggestion from Dean, who wanted to learn about the bush dog. We’re actually going to learn about two animals that share the name bush dog, along with an animal suggested by both Mia and Lydia, the maned wolf.

We’ll start with the bush dog that isn’t a dog. It’s more commonly called the tayra and it’s native to much of Central and South America. It prefers to live in forests, especially tropical forests, but it will travel long distances to find food and can sometimes be found in grasslands and other areas. Despite the name bush dog, it’s not a canid at all. It’s a member of the family Mustelidae, which includes weasels, ferrets, and wolverines. The tayra has a long body and short legs, but it’s also bulkier than most mustelids, more similar to a wolverine. It can grow almost four feet long, or 1.2 meters, including its long tail, and its fur is short and black or dark brown. It also has a patch of lighter fur on its chest that’s a unique shape to every individual, sometimes called a heart patch.

The tayra is mostly active during the day and does a lot of climbing around in trees, where it eats birds, lizards and other reptiles, small mammals, eggs, fruit, honey, and large insects and other invertebrates. It especially likes plantains, which is a type of banana. The tayra will pick green plantains and hide them, then come back to eat them after they ripen. It’s also really good at catching spiny rats, so good that the indigenous peoples in various places would sometimes tame a tayra or two in order to keep spiny rats and other rodents away from their food stores.

The bush dog that is actually a canid is also from South America, but we’re going to start not with the living animal, but with an extinct one. Back in the 19th century, when it was possible to specialize in several fields of science at once, a Danish man named Peter Wilhelm Lund made a name for himself as an archaeologist, a paleontologist, and a zoologist. He moved to Brazil in South America in 1825, went back to Europe in 1829 to finish his doctoral degree, but returned to Brazil in 1832 for the rest of his life. He just really liked it there. He described hundreds of Brazilian plants and animals scientifically and is most well known for his studies of extinct ice age megafauna, along with prehistoric cave paintings.

One of the animals he described was an unusual canid. He discovered its skull in a cave in 1839, so he called it the cave wolf. That makes it sound scary and impressive, but it was actually a fairly small animal. He gave it the scientific name Speothos pacivorus, which means “cave wolf hunter.”

In 1842 Lund described a living canid with a similar skull, although its teeth weren’t as big and it was even smaller than the cave wolf. But he didn’t quite make the connection and placed the living animal in a completely different genus. In 1843 another scientist renamed the animal but again placed it in a completely different genus from the cave wolf.

It’s not unusual for an animal to be studied repeatedly and its taxonomy debated by various scientists as they try to figure out what the animal’s closest relations are. But in the case of the bush dog, it kept getting shuffled from genus to genus every few years, so that in the 180 years since it was originally described it’s been placed and re-placed in nine different genera, until it was finally renamed Speothos venaticus and recognized as a close relation, or possibly the direct descendant, of the cave wolf.

Although the bush dog’s ancestors lived in the highlands of Brazil, the bush dog alive today is adapted for forests. It has partially webbed toes that help it walk on soft soil around water, and it spends a lot of time in water. It’s brown all over, although some individuals have a patch of lighter brown fur on the throat, and its legs and tail are often darker. Puppies are black all over. Its legs are short and it has a short snout and small ears. It actually really does look similar in many ways to the other bush dog, the tayra, although its tail is shorter.

The bush dog is incredibly shy and lives in remote areas that are hard for humans to explore, so we actually don’t know a whole lot about it. It’s so shy that it’s even hard to catch on camera traps. It’s a social animal that sometimes hunts by itself and sometimes in groups, and it eats pretty much anything it can catch. Its main prey is rodents, especially large rodents like capybaras, but it also hunts peccaries, tapirs, and the large flightless bird called the rhea.

Part of the reason the bush dog kept getting moved from genus to genus is that it’s not very similar to other canids. The fact that it even looks a lot like a mustelid gives you an idea of how strange it appears. It has a cute puppy face since its snout and ears are so small, and its long chunky body and short legs make it look a little like a corgi. It’s only been recently that scientists have identified one of its closest relations, and it’s a canid you might not expect. It’s also the canid suggested by Mia and Lydia, because everyone loves the maned wolf.

We’ve talked about the maned wolf before, most recently in episode 167. The maned wolf looks kind of like a short-tailed fox with extremely long legs—like, twice as long as a regular fox’s legs or longer. But the maned wolf isn’t a fox and it isn’t a wolf, or a coyote, or a dog, or any other type of canid. It’s its own thing. It lives in the grasslands of central South America, and it needs extremely long legs to help it see over tall grass. It stands over three and a half feet tall at the shoulder, or 110 cm, while the bush dog only stands about one foot tall, or 30 cm.

The maned wolf is mostly solitary, although mated pairs will sometimes share a territory. It’s an omnivore and eats a lot of plant material in addition to hunting small animals that live in the grass. It especially likes a tomato-like fruit called the wolf apple, and it will also eat carrion. If it catches a large animal, or finds a large animal already dead, it will bury what’s left of the body to eat later. It marks the hole it digs with urine so it can more easily find it later. It also marks its territory with urine.

The maned wolf’s urine contains a chemical called pyrazine, which produces a strong smell. Since the smell of pyrazine is produced by many animals and plants that are toxic, it’s possible that having the smell in its urine helps keep other animals away from the maned wolf’s food caches and out of its territory. Humans recognize the smell of pyrazine as something else, marijuana, since the marijuana plant actually contains pyrazine. In 2006 someone at the Rotterdam Zoo in Holland complained that people were smoking marijuana in the zoo, but when police investigated, they discovered that the smell was actually coming from the maned wolf exhibit. This will never not be funny to me.

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

Thanks for listening!

Episode 355: Tiny Owls

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This week we learn about two tiny owls! Thanks to Elizabeth and Alexandra for their suggestions!

Further reading:

Burrowing Owl

Elf Owl

The burrowing owl is tiny but fierce [photo by Christopher Lindsey, taken from page linked above]:

The elf owl is also tiny but fierce [photo by Matthew Grube, taken from page linked above]:

Show transcript:

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

This week we’re going to learn about two tiny owls. Thanks to Elizabeth and Alexandra for their owl suggestions!

The burrowing owl is native to the Americas, especially the western part of North America, and most of Central and South America. It prefers grasslands and other open areas. It’s a small owl, not much bigger than the average songbird. It’s mostly brown with lighter underparts that are barred with a brown pattern.

You can tell a lot about an owl by the color of its eyes. In general, an owl with dark eyes is most active at night, an owl with orange or red eyes is likely to be most active at dawn and dusk, and an owl with yellow eyes is often active in the day. That’s not a hard and fast rule, but it can help you make a good guess about an owl’s behavior. The burrowing owl has yellow eyes, and it is indeed active in the day. The term for daytime activity is diurnal.

In past episodes I’ve said that owls have long legs that are usually hidden by feathers. In the case of the burrowing owl, its long legs are in plain sight because it spends a lot of the time running around on the ground. It will sometimes chase prey on foot, but other times it will perch on a fence post, tree branch, or some other high place to watch for a small animal to pass by. Then it will swoop down to grab it just like any other owl. It eats mice and other small rodents, lizards, small snakes, frogs, large insects and other invertebrates like scorpions and caterpillars, and birds. It especially likes termites and grasshoppers. Females are more likely to hunt during the daytime, while males are more likely to hunt at night or at dawn and dusk. Sometimes the burrowing owl will eat fruit and seeds too. When the burrowing owl has more food than it can eat, it will store some in underground larders.

The burrowing owl gets its name because it builds a nest in a burrow in the ground, often in burrows dug by other animals like prairie dogs and skunks. Some subspecies of burrowing owl will dig its own burrow, and all subspecies will enlarge an existing burrow until it’s happy with the size. It uses its beak to dig and kicks the dirt out with its feet. Both the male and female will work on the burrow together. Once it’s the right size and shape, the owl will bring in dried grass and other materials to line the burrow. One of its favorite materials is dried animal dung, especially from cattle. The dung releases moisture inside the burrow, making it more comfortable, and attracts insects that the owls eat. Win-win! It will also scatter animal dung around the entrance of its burrow and will sometimes also collect trash like bottle caps and pieces of foil to decorate the entrance.

The female lays her eggs in the burrow and spends most of her time incubating the eggs, only going outside briefly to stretch her legs. The male stands guard at the entrance to the burrow or nearby except when he’s out hunting. He brings food back for the female.

When the eggs hatch, both parents take care of the babies. At first the chicks stay in the burrow, but as they grow older they come out to play outside and start learning how to fly. Since burrowing owls usually nest in small colonies, there’s always an adult watching for danger somewhere nearby.

Most birds abandon their nests after their chicks are grown. The burrowing owl often uses its burrow year-round, although populations that migrate will usually make a new burrow when they return to their summer range. The burrow gives the owls a place to nap during the hottest part of the day, and it’s also a good place to hide if a predator approaches. Rattlesnakes also use burrows for the same purposes, and when a burrowing owl runs from a predator and hides in its burrow, it will mimic the rattling and hissing of an angry rattlesnake. A lot of times that’s enough to make a predator think twice about digging up the burrow.

This is what a burrowing owl sounds like when it’s not imitating an angry rattlesnake:

[burrowing owl call]

The burrowing owl is increasingly threatened by habitat loss and introduced predators likes cats and dogs. Luckily it’s an adaptive bird and is happy to use artificial burrows in protected areas. It’s a useful bird to have around since it eats a lot of insects, prairie dogs, and other animals that are considered pests by humans. Plus it’s an incredibly cute bird. I mean, it’s a tiny owl with long legs! How could you not find that cute?

Small as it is, the burrowing owl isn’t the smallest owl known. The elf owl is even smaller, about the size of a sparrow. It’s only about 5 inches tall, or 13 cm, with a wingspan of only 9 inches, or 22 cm. It lives in parts of the southwestern United States during the summer and parts of Mexico during the winter.

The elf owl is nocturnal like most other owls, and this is where our guideline of owl eye color breaks down, because the elf owl has yellow eyes. Its feathers are mostly gray or grayish-brown with white streaks. When it’s sitting on a twig, it kind of looks like a dead leaf or a broken-off branch.

It mostly eats insects, but it also likes scorpions, spiders, and centipedes. Occasionally it eats small reptiles or mammals. When it catches a scorpion, it removes the stinger before eating the scorpion, but it doesn’t seem to be hurt by actually being stung. It’s a fast, acrobatic flyer and catches insects on the wing, but it also hunts for insects on the ground and has long legs like the burrowing owl.

The elf owl nests in holes made by woodpeckers in trees or cacti, and the male brings the female food while she keeps the eggs warm. After the babies hatch, the male brings them food too and also continues to feed the female for another couple of weeks, until she starts to hunt again. The male will also catch a tiny snake called the western threadsnake, which looks a lot like an earthworm and only grows a foot long at most, or 30 cm, and is usually much smaller than that. It lives underground most of the time and while it has eyes, they don’t work except to sense light and dark. It eats insects, especially termites and ants. When an elf owl catches one of these little snakes, it doesn’t eat it. Instead, it brings the snake back to the nest and lets it go. The snake eats all the insects it can find, including parasites that might hurt the baby owls. Then again, sometimes the nest is inhabited by tree ants that do the same thing, cleaning up all the parasites and scraps of leftover food while not bothering the owls.

If a predator grabs an elf owl, or a scientist nets and handles one, the owl pretends to be dead. A lot of times this will cause the predator to relax its jaw muscles, which often allows the owl to wiggle free and fly away. The scientists are a little more careful about relaxing their hands, but when a scientist handles an elf owl, it’s usually to do a quick examination and maybe put a leg band on for identification purposes, and then they let the owl go again anyway.

This is what an elf owl sounds like:

[elf owl call]

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

Thanks for listening!

Episode 347: Two (Sort of) Spooky Amphibians

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Thanks to Max for suggesting one of our slightly spooky amphibians this week!

Further reading:

New crocodile newt discovered in Vietnam

Further watching:

Brave Wilderness Giant Screaming Frog!

The new Halloween-y crocodile newt discovered in Vietnam [photo by Phung My Trung and taken from the article linked above]:

A smoky jungle frog:

A screenshot from the video linked above:

Show transcript:

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

It’s the end of September and you know what that means: we’re about to start Monster Month! This year I have so many awesome ideas for episodes that we’re starting monster month early, with a non-spooky episode about two sort of spooky-looking amphibians. Thanks to Max for suggesting one of the animals we’re about to talk about!

Instead of rating the monster month episodes on a spookiness scale from one to five ghosts, this year we’re rating them on a spookiness scale of one to five bats, which seems more appropriate. This episode is only one bat, meaning even our younger listeners shouldn’t find it scary.

But first, a quick correction. Thanks very much to Mary for catching a mistake I made in last week’s rhinoceros episode. I said that black rhinos can weigh 18 kilograms, when I should have said 1800 kilograms. 18 kg is about 40 pounds, so I think you can agree that I made a BIG mistake.

Now, on to the “spooky” amphibians.

Lots of amphibians live in southeast Asia, many of them never seen by scientists. In 2018, a team of scientists were studying crocodile newts in Vietnam when they discovered one that didn’t look like any of the many other crocodile newts that live in Asia. Since there are over 30 species known, with new ones being discovered all the time, including seven others from Vietnam alone, they suspected this might be a species new to science.

The new newt lives in high elevations in the central highlands in Vietnam, much farther south and in much higher elevations than the other known crocodile newt species. After the initial finding in 2018, the lead scientist, an amphibian and reptile expert named Phung My Trung (apologies because I probably pronounced his name wrong) spent four years searching for more specimens and learning about them before he described it as a new species.

One thing I love is that he was quoted as saying that the adult newts “were so beautiful that I was shaking and could hardly believe I was holding a live specimen in my hand.” And it is absolutely a gorgeous animal. It’s black with orangey-red markings on its back, lovely Halloween colors, and in fact the markings sort of look like the skull, backbone, and ribs of a cartoon skeleton. Females are bigger than males, and a big female can grow as much as 3 inches long, or 7.5 cm, from snout to vent, not counting its tail that’s almost as long as its body.

That’s pretty much all we know so far about this newt. Because it appears to have such a restricted range, it’s most likely endangered due to habitat loss and climate change, but now that we know it’s there, scientists and conservationists can work to keep it and its habitat safe.

Our other amphibian this week is one suggested by Max. Max, by the way, is an incredible artist who specializes in making reptiles and amphibians out of clay. Max asked specifically about the giant screaming frog, which definitely sounds like a Halloween-themed animal.

The giant screaming frog isn’t the actual name of the frog, or at least I couldn’t find a frog with that specific name. I think it’s from an awesome video posted in 2017. I’ll put a link in the show notes if you want to watch the video, which is a YouTube channel called Brave Wilderness. In the video, a man called Coyote Peterson catches a giant frog called the Smoky Jungle Frog. When he does, the frog makes this sound:

[screaming frog!]

That doesn’t actually sound all that spooky. But it is a warning call so I bet other smoky jungle frogs think it’s terrifying!

The smoky jungle frog lives in tropical and subtropical areas of Central and northern South America, where it lives in swamps, ponds, and even rivers, especially in rainforest environments. It’s a bit unusual in that males are larger than females, although only slightly. Both males and females grow about 7 inches long from snout to vent, or 18 cm, and are a mottled brown with darker spots and stripes that help them blend in with dead leaves on the forest floor.

The smoky jungle frog is nocturnal, and during the day it stays hidden in a burrow or buries itself in fallen leaves. At night it comes out to find food, and because it’s such a big, strong frog, it eats animals much larger than insects. It’s been observed eating small birds, especially baby birds, bats, snakes up to 19 inches long, or 50 cm, lizards, and sometimes even other frogs, including poison dart frogs. How embarrassing would that be if you were a bat, with strong wings and the amazing ability to echolocate, and you got eaten by a frog.

When a frog feels threatened, it has several ways to deter potential predators. It can make itself look even bigger by puffing its body up and standing up higher on its legs instead of sitting in a typical frog squat. It also secretes a toxin through its skin, which not only makes it really slippery but also makes it taste awful. It’s not dangerous to humans but can result in a painful burning sensation and rash if the toxin gets into a cut on the skin. If any of the mucus gets into your eyes, they will swell up painfully for hours.

The frog will also give its alarm call if something grabs it. Let’s listen to it again:

[frog ‘screaming’]

During mating season, the male develops little spikes near his wrists and on his chest. This helps him grasp a female without slipping off so he can fertilize her eggs as she lays them. The male uses his back legs to churn up the water and mix it with mucus and sperm to create a foamy nest for the female’s eggs, which protects the eggs from predators and makes sure they won’t dry out. The eggs hatch a few days later, and the tadpoles stay in the nest at first where they eat…well, they eat each other. The tadpoles that hatch first eat the other eggs, and the bigger tadpoles eat the smaller tadpoles. Soon, though, rain washes them out of the nest into open water, where they spend the next month or so eating small insects and algae until they metamorphose into little frogs that live on land. Unlike many frogs, the toes of the smoky jungle frog aren’t webbed since they don’t spend much time in the water.

So many times in this podcast I have to explain that an animal is endangered, so I’m happy to report that the smoky jungle frog is doing just fine. It’s a common animal throughout its range.

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

Thanks for listening!

Episode 338: Updates 6 and an Arboreal Clam!?!

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This week we have our annual updates and corrections episode, and at the end of the episode we’ll learn about a really weird clam I didn’t even think was real at first.

Thanks to Simon and Anbo for sending in some corrections!

Further reading:

Lessons on transparency from the glass frog

Hidden, never-before-seen penguin colony spotted from space

Rare wild asses spotted near China-Mongolia border

Aye-Ayes Use Their Elongated Fingers to Pick Their Nose

Homo sapiens likely arose from multiple closely related populations

Scientists Find Earliest Evidence of Hominins Cooking with Fire

153,000-Year-Old Homo sapiens Footprint Discovered in South Africa

Newly-Discovered Tyrannosaur Species Fills Gap in Lineage Leading to Tyrannosaurus rex

Earth’s First Vertebrate Superpredator Was Shorter and Stouter than Previously Thought

252-Million-Year-Old Insect-Damaged Leaves Reveal First Fossil Evidence of Foliar Nyctinasty

The other paleo diet: Rare discovery of dinosaur remains preserved with its last meal

The Mongolian wild ass:

The giant barb fish [photo from this site]:

Enigmonia aenigmatica, AKA the mangrove jingle shell, on a leaf:

Show transcript:

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

This week is our annual updates and corrections episode, but we’ll also learn about the mangrove jingle shell, a clam that lives in TREES. A quick reminder that this isn’t a comprehensive updates episode, because that would take 100 years to prepare and would be hours and hours long, and I don’t have that kind of time. It’s just whatever caught my eye during the last year that I thought was interesting.

First, we have a few corrections. Anbo emailed me recently with a correction from episode 158. No one else caught this, as far as I can remember. In that episode I said that geckos don’t have eyelids, and for the most part that’s true. But there’s one family of geckos that does have eyelids, Eublepharidae. This includes the leopard gecko, and that lines up with Anbo’s report of having a pet leopard gecko who definitely blinked its eyes. This family of geckos are sometimes even called eyelid geckos. Also, Anbo, I apologize for mispronouncing your name in last week’s episode about shrimp.

After episode 307, about the coquí and glass frogs, Simon pointed out that Hawaii doesn’t actually have any native frogs or amphibians at all. It doesn’t even have any native reptiles unless you count sea snakes and sea turtles. The coqui frog is an invasive species introduced by humans, and because it has no natural predators in Hawaii it has disrupted the native ecosystem in many places, eating all the available insects. Three of the Hawaiian islands remain free of the frogs, and conservationists are working to keep it that way while also figuring out ways to get them off of the other islands. Simon also sent me the chapter of the book he’s working on that talks about island frogs, and I hope the book is published soon because it is so much fun to read!

Speaking of frogs, one week after episode 307, an article about yet another way the glass frog is able to hide from predators was published in Science. When a glass frog is active, its blood is normal, but when it settles down to sleep, the red blood cells in its blood collect in its liver. The liver is covered with teensy guanine crystals that scatter light, which hides the red color from view. That makes the frog look even more green and leaf-like!

We’ve talked about penguins in several episodes, and emperor penguins specifically in episode 78. The emperor penguin lives in Antarctica and is threatened by climate change as the earth’s climate warms and more and more ice melts. We actually don’t know all that much about the emperor penguin because it lives in a part of the world that’s difficult for humans to explore. In December 2022, a geologist named Peter Fretwell was studying satellite photos of Antarctica to measure the loss of sea ice when he noticed something strange. Some of the ice had brown stains.

Dr Fretwell knew exactly what those stains were: emperor penguin poop. When he obtained higher-resolution photos, he was able to zoom in and see the emperor penguins themselves. But this wasn’t a colony he knew about. It was a completely undiscovered colony.

In episode 292 we talked about a mystery animal called the kunga, and in that episode we also talked a lot about domestic and wild donkeys. We didn’t cover the Mongolian wild ass in that one, but it’s very similar to wild asses in other parts of the world. It’s also called the Mongolian khulan. It used to be a lot more widespread than it is now, but these days it only lives in southern Mongolia and northern China. It’s increasingly threatened by habitat loss, climate change, and poaching, even though it’s a protected animal in both Mongolia and China.

In February of 2023, a small herd of eight Mongolian wild asses were spotted along the border of both countries, in a nature reserve. A local herdsman noticed them first and put hay out to make sure the donkeys had enough to eat. The nature reserve has a water station for wild animals to drink from, and has better grazing these days after grassland ecology measures were put into place several years ago.

In episode 233 we talked about the aye-aye of Madagascar, which has weird elongated fingers. Its middle finger is even longer and much thinner than the others, which it uses to pull invertebrates from under tree bark and other tiny crevices. Well, in October of 2022 researchers studying aye-ayes started documenting another use for this long thin finger. The aye-ayes used it to pick their noses. It wasn’t just one aye-aye that wasn’t taught good manners, it was widespread. And I hope you’re not snacking while I tell you this, the aye-aye would then lick its finger clean. Yeah. But the weirdest thing is that the aye-aye’s thin finger is so long that it can potentially reach right through the nose right down into the aye-aye’s throat.

It’s pretty funny and gross, but wondering why some animals pick their noses is a valid scientific question. A lot of apes and monkeys pick their noses, as do humans (not that we admit it most of the time), and now we know aye-ayes do too. The aye-aye is a type of lemur and therefore a primate, but it’s not very closely related to apes and monkeys. Is this just a primate habit or is it only seen in primates because we have fingers that fit into our nostrils? Would all mammals pick their nose if they had fingers that would fit up in there? Sometimes if you have a dried snot stuck in your nose, it’s uncomfortable, but picking your nose can also spread germs if your fingers are dirty. So it’s still a mystery why the aye-aye does it.

A recent article in Nature suggests that Homo sapiens, our own species, may have evolved not from a single species of early human but from the hybridization of several early human species. We already know that humans interbred with Neandertals and Denisovans, but we’re talking about hybridization that happened long before that between hominin species that were even more closely related.

The most genetically diverse population of humans alive today are the Nama people who live in southern Africa, and the reason they’re so genetically diverse is that their ancestors have lived in that part of Africa since humans evolved. Populations that migrated away from the area, whether to different parts of Africa or other parts of the world, had a smaller gene pool to draw from as they moved farther and farther away from where most humans lived.

Now, a new genetic study of modern Nama people has looked at changes in DNA that indicate the ancestry of all humans. The results suggest that before about 120,000 to 135,000 years ago, there was more than one species of human, but that they were all extremely closely related. Since these were all humans, even though they were ancient humans and slightly different genetically, it’s probable that the different groups traded with each other or hunted together, and undoubtedly people from different groups fell in love just the way people do today. Over the generations, all this interbreeding resulted in one genetically stable population of Homo sapiens that has led to modern humans that you see everywhere today. To be clear, as I always point out, no matter where people live or what they look like, all people alive today are genetically human, with only minor variations in our genetic makeup. It’s just that the Nama people still retain a lot of clues about our very distant ancestry that other populations no longer show.

To remind everyone how awesome out distant ancestors were, here’s one new finding of how ancient humans lived. We know that early humans and Neandertals were cooking their food at least 170,000 years ago, but recently archaeologists found the remains of an early hominin settlement in what is now Israel where people were cooking fish 780,000 years ago. There were different species of fish remains found along with the remains of cooking fires, and some of the fish are ones that have since gone extinct. One was a carp-like fish called the giant barb that could grow 10 feet long, or 3 meters.

In other ancient human news, the oldest human footprint was discovered recently in South Africa. You’d think that we would have lots of ancient human footprints, but that’s actually not the case when it comes to footprints more than 50,000 years old. There are only 14 human footprints older than that, although there are older footprints found made by ancestors of modern humans. The newly discovered footprint dates to 153,000 years ago.

It wouldn’t be an updates episode without mentioning Tyrannosaurus rex. In late 2022 a newly discovered tyrannosaurid was described. It lived about 76 million years ago in what is now Montana in the United States, and while it wasn’t as big as T. rex, it was still plenty big. It probably stood about seven feet high at the hip, or a little over 2 meters, and might have been 30 feet long, or 9 meters. It probably wasn’t a direct ancestor of T. rex, just a closely related cousin, although we don’t know for sure yet. It’s called Daspletosaurus wilsoni and it shows some traits that are found in older Tyrannosaur relations but some that were more modern at the time.

Dunkleosteus is one of a number of huge armored fish that lived in the Devonian period, about 360 million years ago. We talked about it way back in episode 33, back in 2017, and at that time paleontologists thought Dunkleosteus terrelli might have grown over 30 feet long, or 9 meters. It had a heavily armored head but its skeleton was made of cartilage like a shark’s, and cartilage doesn’t generally fossilize, so while we have well-preserved head plates, we don’t know much about the rest of its body.

With the publication in early 2023 of a new study about dunkleosteus’s size, we’re pretty sure that 30 feet was a huge overestimation. It was probably less than half that length, maybe up to 13 feet long, or almost 4 meters. Previous size estimates used sharks as size models, but dunkleosteus would have been shaped more like a tuna. Maybe you think of tuna as a fish that makes a yummy sandwich, but tuna are actually huge and powerful predators that can grow up to 10 feet long, or 3 meters. Tuna are also much heavier and bigger around than sharks, and that was probably true for dunkleosteus too. The study’s lead even says dunkleosteus was built like a wrecking ball, and points out that it was probably the biggest animal alive at the time. I’m also happy to report that people have started calling it chunk-a-dunk.

We talked about trace fossils in episode 103. Scientists can learn a lot from trace fossils, which is a broad term that encompasses things like footprints, burrows, poops, and even toothmarks. Recently a new study looked at insect damage on leaves dating back 252 million years and learned something really interesting. Some modern plants fold up their leaves at night, called foliar nyctinasty, which is sometimes referred to as sleeping. The plant isn’t asleep in the same way that an animal falls asleep, but “sleeping” is a lot easier to say than foliar nyctinasty. Researchers didn’t know if folding leaves at night was a modern trait or if it’s been around for a long time in some plants. Lots of fossilized leaves are folded over, but we can’t tell if that happened after the leaf fell off its plant or after the plant died.

Then a team of paleontologists from China and Sweden studying insect damage to leaves noticed that some leaves had identical damage on both sides, exactly as though the leaf had been folded and an insect had eaten right through it. That’s something that happens in modern plants when they’re asleep and the leaves are folded closed.

The team looked at fossilized leaves from a group of trees called gigantopterids, which lived between 300 and 250 million years ago. They’re extinct now but were advanced plants at the time, some of the earliest flowering plants. They also happen to have really big leaves that often show insect damage. The team determined that the trees probably did fold their leaves while sleeping.

In episode 151 we talked about fossils found with other fossils inside them. Basically it’s when a fossil is so well preserved that the contents of the dead animal’s digestive system are preserved. This is incredibly rare, naturally, but recently a new one was discovered.

Microraptor was a dinosaur that was only about the size of a modern crow, one of the smallest dinosaurs, and it probably looked a lot like a weird bird. It could fly, although probably not very well compared to modern birds, and in addition to front legs that were modified to form wings, its back legs also had long feathers to form a second set of wings.

Several exceptionally well preserved Microraptor fossils have been discovered in China, some of them with parts of their last meals in the stomach area, including a fish, a bird, and a lizard, so we knew they were generalist predators when it came to what they would eat. Now we have another Microraptor fossil with the fossilized foot of a mammal in the place where the dinosaur’s stomach once was. So we know that Microraptor ate mammals as well as anything else it could catch, although we don’t know what kind of mammal this particular leg belonged to. It may be a new species.

Let’s finish with the mangrove jingle shell. I’ve had it on the list for a long time with a lot of question marks after it. It’s a clam that lives in trees, and I actually thought it might be an animal made up for an April fool’s joke. But no, it’s a real clam that really does live in trees.

The mangrove jingle shell lives on the mangrove tree. Mangroves are adapted to live in brackish water, meaning a mixture of fresh and salt water, or even fully salt water. They mostly live in tropical or subtropical climates along coasts, and especially like to live in waterways where there’s a tide. The tide brings freshly oxygenated water to its roots. A mangrove tree needs oxygen to survive just like animals do, but it has trouble getting enough through its roots when they’re underwater. Its root system is extensive and complicated, with special types of roots that help it stay upright when the tide goes out and special roots called pneumatophores, which stick up above the water or soil and act as straws, allowing the tree to absorb plenty of oxygen from the air even when the rest of the root system is underwater. These pneumatophores are sometimes called knees, but different species of mangrove have different pneumatophore shapes and sizes.

One interesting thing about the mangrove tree is that its seeds actually sprout while they’re still attached to the parent tree. When it’s big enough, the seedling drops off its tree into the water and can float around for a long time before it finds somewhere to root. If can even survive drying out for a year or more.

The mangrove jingle shell clam lives in tropical areas of the Indo-Pacific Ocean, and is found throughout much of coastal southeast Asia all the way down to parts of Australia. It grows a little over one inch long, or 3 cm, and like other clams it finds a place to anchor itself so that water flows past it all the time and it can filter tiny food particles from the water. It especially likes intertidal areas, which happens to be the same area that mangroves especially like.

Larval jingle shells can swim, but they need to find somewhere solid to anchor themselves as they mature. When a larva finds a mangrove root, it attaches itself and grows a domed shell. If it finds a mangrove leaf, since mangrove branches often trail into the water, it attaches itself to the underside and grows a flatter shell. Clams attached to leaves are lighter in color than clams attached to roots or branches. Fortunately, the mangrove is an evergreen tree that doesn’t drop its leaves every year.

So there you have it. Arboreal clams! Not a hoax or an April fool’s joke.

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 336: The Turtle Ant and the Alien Butt Spider

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Thanks to Kari for suggesting this week’s topics! Definitely check out her book Butt or Face?, which is funny and has lots of animal information!

Further reading:

Butt or Face? by Kari Lavelle

GBIF: Araneus praesignis [the spider pictures below come from this site]

The turtle ant’s body is flattened and the soldier caste ants have specialized head shapes to block the nest entrances:

The alien butt spider has a butt that looks like an alien’s face!

The alien butt spider hides during the day in its leaf fort:

Show transcript:

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

This week we’re going to learn about two really weird invertebrates suggested by Kari. One of these two animals is her favorite and the other is a weird ant from a book she wrote. Kari’s full name is Kari Lavelle and her book is for kids, called Butt or Face? It actually releases tomorrow as this episode goes live, so if you’re listening to this episode on Monday, July 10, 2023, you still have time to preorder the book, or you can just wait a day and run out to your local bookstore or library to get a copy.

Kari was nice enough to send me a copy of the book and it’s really funny and interesting. It’s partly a game where you look at a picture and decide whether it shows an animal’s butt or its face. It’s a lot harder than you’d think! You make your guess and turn the page to find out if you’re right and learn about the animal. It’s very fun and I actually guessed wrong on one animal, but I’m not telling you which one. There’s a link in the show notes if you want to learn more about the book and maybe order a copy for yourself.

Anyway, let’s talk about the ant first, because it’s actually one I’ve had on the list to talk about for a while. I was really excited to see it in Kari’s book. It’s called the turtle ant, sometimes called the “door head” ant. That gives you a clue as to whether its picture in the book features its butt or its face.

The turtle ant is any of the well over 100 species of ant in the genus Cephalotes, which are native to the Americas. Most live in Central and South America, especially in tropical and subtropical areas. Almost all species live in trees, nesting in cavities originally made by beetle larvae.

For the most part, turtle ants are pretty typical compared to other ant species. They have a generalized diet, eating pretty much anything they find. This includes plant material, dead insects and other animals they find, bird poop, nectar, and even pollen in some species. Each colony has a single queen that mates with multiple males and lays all the eggs for the colony. Worker ants tend the eggs and larvae, gather food, and keep the colony clean. But as in some other ants, many species of turtle ant have a soldier caste. These are worker ants who are specialized to defend the nest. We talked about army ants recently, in episode 328, and also back in episode 185, and army ant soldiers have massive sharp mandibles that can inflict painful bites. But the turtle ant soldiers don’t have sharp mandibles and aren’t aggressive. They have one job, and that job is to stand at the nest’s entrances and stop them up with their heads, only moving when another ant needs to get through.

As a result, turtle ant soldiers have weird-shaped heads. The head shape varies from species to species, with some looking more normal and some being heavily armored and strangely shaped. Well, they’re not strangely shaped except in comparison to an ordinary ant head. They’re shaped exactly right to do the job they’ve evolved to do, be a door. In some species, the top of the soldier’s head is completely round and flattened, just the right size and shape to block the entrance.

Turtle ants have another ability that they share with some other ants. If an ant falls from the twig or branch it’s climbing on, instead of just falling to the ground, it can glide back to the tree trunk. Turtle ants have flattened bodies, which helps catch the air like a tiny ant-shaped parachute. Unlike other ants that do this, which glide head-first, the turtle ant glides abdomen-first. It uses its legs and head to adjust which way it’s gliding, and most of the time it lands safely on the tree trunk.

There are undoubtedly more turtle ant species than we know about so far, and we actually don’t know very much about most of the species we have discovered. Most turtle ants live in trees, and that makes them hard to study.

There’s actually a spider called the ant-mimicking crab spider that eats turtle ants. It looks so much like a turtle ant worker that it can get close to the actual ants before it’s recognized as a predator, at which point it has a good chance of grabbing an ant to eat before the ant can run away. But that’s not actually the type of spider we’re talking about next.

The other animal we’re talking about today isn’t one from the book, it just happens to be one of Kari’s favorite animals *cough*sequel*cough*. It’s called the alien butt spider and it is completely awesome, as you can tell from the name.

The alien butt spider lives in Queensland, Australia, and it gets its name because—maybe you should just guess. I’ll wait.

Yes, you’re right! The abdomen of the spider has black or dark blue-green markings that look for all the world like the face of a tiny space alien from a movie. The spider itself is mostly green and very small, with a big female only growing about 8 mm long, although its legspan can be 20 mm across. Males are smaller, mostly because the male has a much smaller abdomen.

Its scientific name is Bijoaraneus praesignis, changed in December 2021 from Araneus praesignis. It’s also called the outstanding orbweaver or green orbweaver. Like many spiders, especially orbweavers, it’s mostly active at night. It spins a big round web that looks like the kind you see on Halloween decorations, because that’s the kind of web most orbweavers make, and at night it waits on or near the web for an insect to get stuck in it. During the day, though, the alien butt spider needs to hide. It makes what’s called a retreat in a leaf that’s partially closed or curled. The spider spins a thick layer of silk across the edges of the leaf that turns it into basically a little leaf fort, then crawls inside. The underside of the spider is plain greenish-yellow with no markings, so it’s hard to see against the leaf, especially through the layer of silk.

The spider’s abdomen is green with a yellow or white pattern on top, with black eye spots visible from the rear. The eye spots show up really well against the yellow or white pattern. But the spider also has black markings at the front of its abdomen, which also look like eyespots from some angles. The rest of its body is green, greeny-yellow, and brown, which helps it blend into leafy backgrounds.

Naturally, the alien butt spider is not actually trying to look like an alien. That’s something humans have decided it looks like because it’s green and the eyespots are so large. The spider just wants potential predators to see the eyespots and think, “Darn, that animal already saw me so I can’t sneak up on it. I won’t waste my energy trying to grab it.” Or maybe, “Uh oh, look at the size of that animal’s eyes! I must be looking at the head of a very large animal that might eat me, plus it’s looking right at me. I’d better run.”

Even though it looks kind of spooky, the alien butt spider is completely harmless to humans. We also don’t know much about it, so while it seems to be a common spider within its range, we don’t know for sure if it’s potentially endangered. It’s best to leave this little alien alone no matter how cute it is (and it is very cute).

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 334: Piranha!

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Thanks to David for this week’s suggestion, the piranha!

Further reading:

Florida wildlife officer’s fish seizure nibbles at illegal piranha sales

How Teddy Roosevelt Turned Piranhas into Ferocious Maneaters

The beautiful butterfly peacock bass (not a piranha):

The red-bellied piranha (By H. Zell – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=82557603):

Chompy chompy teeth:

Show transcript:

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

This week we’re covering a type of fish that I absolutely cannot believe we haven’t talked about before. It’s the piranha! Thanks to David for telling me on Mastodon about a piranha incident that led to me realizing we don’t have an episode about it yet.

David’s incident is something that happened in Florida in 2009. In October of that year, a 14-year-old boy named Jake was fishing in a retention pond in West Palm Beach, Florida, which he did a lot. He’d caught all kinds of unusual fish in the pond, including a butterfly peacock bass, which is yellow, green, or even orange in color with three black stripes on its back. It can grow well over two feet long, or 74 cm. The peacock bass is native to tropical areas of South America but was deliberately introduced to Florida in 1984 to prey on other invasive species. This actually worked, and because the fish can’t survive if the water gets too cold, it can’t spread very far.

But on this particular October day in 2009, Jake caught a fish that no one wanted to find in Florida, a red-bellied piranha! The teenager took the fish to his dad, who called the Florida Fish and Wildlife Conservation Commission. A wildlife biologist investigated and caught another piranha in the same pond the following week.

That was enough of a problem that wildlife officials decided to poison the entire 4-acre pond rather than risk having piranhas become naturalized in Florida. The poison killed every single fish in the pond, including at least one other piranha, although it was a poison that quickly broke down into nontoxic compounds. The pond was later restocked with bluegills and other native fish.

The reason that Florida wildlife officials would rather kill all the fish in a big pond rather than let any piranhas live is that Florida is very similar to the piranha’s native habitat in South America. Florida already has enough issues with invasive species like the Burmese python, cane toad, lionfish, and giant land snail without adding another fish that’s famous for its sharp teeth and voracious appetite. If the piranha became established in Florida, it could drive all kinds of native fish and other animals to extinction very quickly.

This has actually happened in parts of China, where red-bellied piranha were first found in the wild in 1990 and have since spread throughout much of South China. In some waterways, up to half of the native fish have disappeared after piranha and other invasive species became established.

But wait, you may be thinking, what about the danger to humans? Aren’t piranhas incredibly dangerous to swimmers?

The red-bellied piranha is the species that most people think is dangerous to people. We’ve all heard the stories and maybe seen movies where a pack of piranha attack someone swimming along, and within minutes all that’s left of them is a skeleton. But it may not surprise you to learn that those stories are fake, but they’re widespread for an unusual reason.

Back in 1913, the former U.S. President Teddy Roosevelt, who we talked about in episode 284 about the teddy bear, took part in an expedition to the Amazon basin in South America. The expedition was arranged by the Brazilian government, who invited Roosevelt along.

The expedition planned to explore the headwaters of the Amazon and it did, at great peril. Three people died and almost everyone got sick from malaria or some other disease, including Roosevelt, who got a cut on his leg that became badly infected. One of the three people who died was murdered by another expedition member, and instead of taking the murderer home to face justice, they just…left him in the jungle, a looooooooong way from anywhere or anyone.

Anyway, one of the things Roosevelt saw early on in the trip was something he told everyone about later, in gruesome detail. You’ve probably heard about it too. The local dignitaries took Roosevelt and the other expedition members on a tour of their town, showing things off, as people do all over the world when they have important visitors. They also showed how ferocious the local piranhas were by driving a cow into the water. A pack of piranhas attacked the cow, and within minutes it was nothing but a skeleton, just like in the movies!

But wait, you’re probably thinking again, I just said that was all fake! Did it really happen? It did, but not the way it sounds. The whole cruel spectacle was arranged ahead of time by the local dignitaries. They had people capture piranhas from miles away and bring them to one section of the river, where they were penned in with a net and not given any food for days. By the time the cow was driven into the makeshift pen, the piranhas were starving and desperate. Under normal circumstances, they would have never attacked the cow.

The red-bellied piranha and its relations are actually mild-mannered fish who only want to eat small fish, snails, insects, and other tiny animals, along with fruit and leaves. It will also sometimes eat dead animals it finds, which has led to people assuming piranhas killed someone swimming in the water when actually the person drowned and the piranhas just, you know, cleaned things up a little.

The red-bellied piranha can grow up to 20 inches long, or 50 cm, and is usually silvery-gray in color with black markings and a reddish belly. It does have big sharp teeth, but so do lots of other fish. Most importantly, the piranha doesn’t hunt in packs. It hunts individually most of the time, but it may stay in a school with other piranhas to help it avoid predators. If a caiman or something decides it wants a piranha snack, any given individual fish in a school is likely to escape the caiman, whereas a fish by itself has a much higher chance of being grabbed and eaten.

The piranha communicates with other piranha by sound. Fish aren’t usually famous for making noise, but the piranha can use its swim bladder as a resonant chamber. It uses special muscles to make a low-pitched drumming sound, usually to warn another piranha away from whatever food it’s found.

Aquarium enthusiasts sometimes keep piranha as pets, but they need special care. A piranha won’t eat meat that’s going bad, so it has to have fresh meat or live animals it can catch, and some animals can make the piranha sick, like goldfish. It’s also a messy eater, so its water will get yucky very quickly and has to be continually changed. And, of course, in some places people aren’t allowed to own piranha at all. You know, places like Florida.

The red-bellied piranha is the largest living species, but 8 to 10 million years ago a species named Megapiranha could grow as much as four feet long, or 1.27 meters. If you’d lived back then, you might have needed to be a little more careful where you swam.

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 332: Hunting Partners and Mutualism

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Thanks to Vaughn and Jan for their suggestions this week! We’re going to learn about mutualism of various types.

Further reading:

The odd couple: spider-frog mutualism in the Amazon rainforest

What Birds, Coyotes, and Badgers Know About Teamwork

Octopuses punch fishes during collaborative interspecific hunting events

An Emotional Support Dog Is the Only Thing That Chills Out a Cheetah

Buddies [picture from the first link above]:

The honeyguide bird:

Cheetahs and dogs can be friends:

Show transcript:

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

This week we’re going to learn about a topic that I’ve been wanting to cover for a long time, mutualism. It’s a broad topic so we won’t try to cover everything about it in this episode, just give an overview with some examples. Vaughn suggested symbiotic behavior ages ago, and Jan gave me a great example of this, also ages ago, so thanks to both of them!

Mutualism is similar to other terms, including symbiosis, often referred to as “a symbiotic relationship.” I’m using mutualism as a general term, but if you want to learn more you’ll quickly find that there are lots of terms referring to different interspecies relationships. Basically we’re talking about two unrelated organisms interacting in a way that’s beneficial to both. This is different from commensalism, where one organism benefits and the other doesn’t but also isn’t harmed, and parasitism, where one organism benefits and the other is harmed.

We’ll start with the suggestion from Jan, who alerted me to this awesome pair of animals. Many different species have developed this relationship, but we’ll take as our specific example the dotted humming frog that lives in parts of western South America.

The dotted humming frog is a tiny nocturnal frog that barely grows more than half an inch long from snout to vent, or about 2 cm. It lives in swamps and lowland forests and spends most of the day in a burrow underground. It comes out at night to hunt insects, especially ants. It really loves ants and is considered an ant specialist. That may be why the dotted humming frog has a commensal relationship with a spider, the Colombian lesserblack tarantula.

The tarantula is a lot bigger than the frog, with its body alone almost 3 inches long, or 7 cm. Its legspan can be as much as 8 and a half inches across, or 22 cm. It’s also nocturnal and spends the day in its burrow, coming out at night to hunt insects and other small animals, although not ants. It’s after bigger prey, including small frogs. But it doesn’t eat the dotted humming frog. One or even more of the frogs actually lives in the same burrow as the tarantula and they come out to hunt in the evenings at the same time as their spider roommate.

So what’s going on? Obviously the frog gains protection from predators by buddying up with a tarantula, but why doesn’t the tarantula just eat the frog? Scientists aren’t sure, but the best guess is that the frog protects the spider’s eggs from ants. Ants like to eat invertebrate eggs, but the dotted humming frog likes to eat ants, and as it happens the female Colombian lesserblack tarantula is especially maternal. She lays about 100 eggs and carries them around in an egg sac. When the babies hatch, they live with their mother for up to a year, sharing food and burrow space.

This particular tarantula also gets along with another species of frog that also eats a lot of ants. Researchers think the spiders distinguish the frogs by smell. The ant-eating frogs apparently smell like friends, or at least useful roommates, while all other frogs smell like food. Or, of course, it’s possible that the ant-eating frogs smell and taste bad to the spider. Either way, both the frogs and the tarantulas benefit from the relationship–and this pairing of tiny frogs and big spiders is one that’s actually quite common throughout the world.

Mutualism is everywhere, from insects gathering nectar to eat while pollenating flowers at the same time, to cleaner fish eating parasites from bigger fish, to birds eating fruit and pooping out seeds that then germinate with a little extra fertilizer. Many mutualistic relationships aren’t obvious to us as humans until we’ve done a lot of careful observations, which is why it’s so important to protect not just a particular species of animal but its entire ecosystem. We don’t always know what other animals and plants that animal depends on to survive, and vice versa.

Sometimes an individual animal will work together with an individual of another species to find food. This may not happen all the time, just when circumstances are right. Sometimes, for example, a coyote will pair up with a badger to hunt. The coyote is closely related to wolves and can run really fast, while the American badger can dig really fast. Both are native to North America. They also both really like to eat prairie dogs, a type of rodent that can run really fast and lives in a burrow. Some prairie dog tunnels can extend more than 30 feet, or 10 meters, with multiple exits. The badger can dig into the burrow and if the prairie dog leaves through one of the exits, the coyote chases after it. When one of the predators catches the prairie dog, they don’t share the meal but they will often continue to hunt together until both are able to eat.

Other animals hunt together too. Moray eels will sometime pair up with a fish called the grouper in a similar way as the coyote and badger. The grouper is a fast swimmer while the eel can wriggle into crevices in rocks or coral. The grouper will swim up to the eel and shake its head rapidly to initiate a hunt, and if the grouper has seen a prey item disappear into a crevice, it will lead the eel to the crevice and shake its head at it again.

Groupers also sometimes pair up with octopuses to hunt together, as will some other species of fish. Like the eel, the octopus can enter crevices to chase an animal that’s trying to hide. But the octopus isn’t always a good hunting partner, because if the grouper catches a fish, sometimes the octopus will punch the grouper and steal its fish. Not cool, octopus.

Birds have mutualistic relationships too, including the honeyguide that lives in parts of Africa and Asia. It’s a little perching bird that’s mostly gray and white or brown and white, with the males of some species having yellow markings. It eats insects, spiders, and other invertebrates, and it especially likes bee larvae. But it’s just a little bird and can’t break open wild honeybee hives by itself.

Some species of honeyguide that live in Africa have figured out that humans can break open beehives. When the honeyguide bird finds a beehive, it will fly around until it hears the local people’s hunting calls. The bird will then respond with a distinct call of its own, alerting the people, and will guide them to the beehive. This has been going on for thousands of years. The humans gather the honey, the honeyguide feasts on the bee larvae and wax, and everyone has a good day except the bees.

The honeyguide is also supposed to guide the honey badger to beehives, but there’s no definitive evidence that this actually happens. Honey badgers do like to eat honey and bee larvae, though, and when a honey badger breaks open a beehive, honeyguides and other birds will wait until it’s eaten what it wants and will then pick through the wreckage for any food the badger missed. But the honeyguide might lead the honey badger to the hive, we just don’t know for sure.

Humans sometimes even help other animals into a commensal relationship. Vaughn gave me an example of a cheetah in a zoo who became best friends with a dog. This hasn’t just happened once, it’s happened lots of times because zookeepers have found that it helps cheetahs kept in captivity. Cheetahs are social animals but sometimes a zoo doesn’t have a good companion for a cheetah cub. The cub could be in danger from older, unrelated cheetahs, but a cheetah all on its own is prone to anxiety. It’s so important for a cheetah to have a sibling that if a mother cheetah only has one cub, or if all but one cub dies, a lot of times she’ll abandon the single cub. If this happens in the wild, it’s sad, but if it happens in captivity the zoo needs to help the cub.

To do this, the zoo will pair the cub with a puppy of a sociable, large breed of dog, such as a Labrador or golden retriever. The cub and the puppy grow up together. The cheetah has a mellow friend who helps alleviate its anxiety, and the dog has a friend who’s really good at playing chase.

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 just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!