Episode 265: Penguins!

Thanks to Page for suggesting we talk about penguins this week!

A big birthday shout-out to EllieHorseLover this week too!

Further reading:

March of the penguins (in Norway)

Rare Yellow Penguin Bewilders Scientists

Giant Waikato penguin: school kids discover new species

An ordinary king penguin with the rare “yellow” king penguin spotted in early 2021 (photo by Yves Adams, taken from article linked above):

Show transcript:

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

I was looking over the ideas list recently and noticed that Page had suggested we cover a specific bird way back in 2020! It’s about time we get to it, so thanks to Page we’re going to learn about penguins this week, including a penguin mystery.

But first, we have a birthday shout-out! Happy birthday to EllieHorseLover, whose birthday comes right before next week’s episode comes out. Have a fantastic birthday, Ellie, and I agree with you about horses. They are awesome and so are you.

Also, a quick correction from last week’s episode about Dolly the dinosaur. If you listened to episode 264 the day it came out, you heard the incorrect version, but I was able to correct it and upload the new version late that day. Many thanks to Llewelly, who pointed out that Dolly hasn’t actually been identified as a Diplodocus, just as a sauropod in the family Diplodocidae. Paleontologists are still studying the fossil and probably will be for some time. Also, I said that sauropods aren’t related to birds but that’s not the case. Sauropods share a common ancestor with birds and that’s why they both have the same kind of unusual respiratory system.

So, speaking of birds, it’s time to learn about penguins! We’ve talked about penguins twice before, but not recently at all. It’s about time we really dug into the topic.

Penguins live in the southern hemisphere, including Antarctica. The only exception is the Galapagos penguin, which we talked about in episode 99, which lives just north of the equator. Penguins are considered aquatic birds because they’re so well adapted to swimming and they spend most of their time in the ocean finding food. Instead of wings, their front limbs are flippers that they use to maneuver in the water. They’re incredibly streamlined too, with a smooth, dense coat of feathers to help keep them warm in cold water without slowing them down.

One of the ways a penguin keeps from freezing in the bitterly cold winters of Antarctica and in cold water is by a trick of anatomy that most other animals don’t have. The artery that supplies blood to the flippers crosses over the veins that return blood from the flippers deeper into the body. The arterial blood is warm since it’s been through the body’s core, but the blood that has just traveled through the flippers has lost a lot of heat. Because the veins and the arteries cross several times, the cold venal blood is warmed by the warm arterial blood where the blood vessels touch, which means the blood returning into the body’s core is warm enough that it doesn’t chill the body.

Penguins groom their feathers carefully to keep them clean and spread oil over them. The oil and the feathers’ nanostructures keep them from icing over when a penguin gets out of the water in sub-zero temperatures. The feathers are not only super-hydrophobic, meaning they repel water, their structure acts as an anti-adhesive. That means ice can’t stick to the feathers no matter how cold it is. In 2016 researchers created a nanofiber membrane that repels water and ice with the same nanostructures found in penguin feathers. It could eventually be used to ice-proof electrical wires and airplane wings.

Penguin feathers also trap a thin layer of air, which helps the penguin stay buoyant in the water and helps keep its skin warm and dry.

While a penguin is awkward on land, it’s fast and agile in the water. It mostly eats small fish, squid and other cephalopods, krill and other crustaceans, and other small animals, and it can dive deeply to find food. The emperor penguin is the deepest diver, with the deepest recorded dive being over 1,800 feet, or 565 meters. The gentoo penguin has been recorded swimming 22 mph underwater, or 36 km/hour.

Penguins are famous for being mostly black and white, but in 2010, a study of an extinct early penguin revealed that it looked much different. The fossil was found in Peru and is incredibly detailed. The flipper shape is clear, proving that even 36 million years ago penguins were already fully aquatic. Even some of the feathers are preserved, allowing researchers to reconstruct the bird’s coloration from melanosomes in the fossilized feathers. They show that instead of black and white, the extinct penguin was reddish-brown and gray. The bird was also one of the biggest penguins known, up to five feet long, or 1.5 meters.

Another species of extinct penguin was discovered in 2006 in New Zealand by a group of school children on a field trip. The New Zealand penguin lived between about 28 and 34 million years ago and while it wasn’t as big as the Peru fossil penguin, it had longer legs that made it about 4.5 feet tall, or 1.4 meters. It was described as a new species in September of 2021 and somehow I missed that one when I was researching the 2021 discoveries episode.

The smallest penguin alive today is the fairy penguin, which only grows 16 inches tall at most, or 40 cm. It lives off the southern coasts of Australia and Chile, and all around New Zealand’s coasts. It’s also called the little blue penguin because its head is gray-blue. The largest penguin is the emperor penguin, which lives in Antarctica and can grow over four feet tall, or 130 cm.

The king penguin looks like a slightly smaller version of the emperor penguin, which makes sense because they’re closely related. It can stand over 3 feet tall, or 100 cm. Its numbers are in decline due to climate change that has caused some of the small fish and squid the penguins eat to move away from the penguin’s nesting grounds. Large-scale commercial fishing has also reduced the number of fish available to penguins. As a result, the penguins have a hard time finding enough food for themselves and their babies. King penguins are protected, though, and conservation efforts are in place to stop commercial fishing near their nesting grounds. A ban on commercial fishing around Robben Island in South Africa, where the endangered African penguin nests, increased the survival of chicks by 18%, so hopefully the same will be true for the king penguin.

In early 2021, a Belgian wildlife photographer named Yves Adams was leading a group of photographers on an island where king penguins live. They spotted a group of the penguins swimming nearby when Adams noticed that one of the penguins seemed really pale. It was yellowish-white instead of black and white, although it did have the yellow markings on its head and breast that other king penguins have. It and the other penguins came ashore and Adams got lots of pictures of it. Ornithologists who have studied the pictures aren’t sure what kind of genetic anomaly has caused the penguin’s coloration, but with luck scientists will be able to find it again and take a genetic sample.

The king penguin is also the subject of a small penguin mystery, but the mystery starts with the great auk. As we talked about in episode 78, the name penguin was originally used for a bird also called the great auk or gairfowl, which lived in the northern hemisphere. It was common throughout its range until people decided to start killing them by the thousands for their feathers and meat. By 1844, the last pair of great auks were killed. The great auk was a black and white aquatic bird that looked a lot like a penguin due to convergent evolution.

The story goes that in the late 1930s people started seeing great auks on the Lofoten Islands off the coast of Norway. Since this was 70 years after the great auk officially went extinct, the reports caused a flurry of excitement.

While a small, scattered population of great auks probably did persist for years or even decades after their official extinction, once an expedition investigated the Lofoten Islands they discovered not auks but penguins. Specifically, a small group of king penguins. How did the penguins get there from their natural range in various sub-Antarctic islands on the other side of the world?

Some reports say whalers captured some penguins as pets and later released them, but it actually appears that the introduction of nine king penguins to two islands off the coast of Norway was done by the Nature Protection Society, backed by the Norwegian government, in 1936. The penguins were still there until at least 1944, with the last sighting coming from 1954.

These weren’t the only penguins released in the islands. In 1938 the Norwegian government released around 60 other penguins from various species onto the islands. The goal was to establish penguin breeding colonies in Norwegian waters in a confused attempt to claim the Antarctic for Norwegian whaling. The real mystery is why they thought that would work.

Very occasionally, a stray penguin is found in the northern hemisphere with no idea how it got there. In the past, people assumed the penguin got lost and swam the wrong way or got pushed away from its homeland by storms, but these days biologists think these lost penguins were transported by fishing boats. Sometimes a penguin will get tangled in a fishing net and hauled aboard by accident, and the fishers will untangle it and keep it as a pet for a while before setting it free. It would be better if the penguin was set free immediately so it could return to its home, but it’s better than being killed. Just ask the penguin.

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 263: Pair Bonds

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Thanks to Ella and Jack for this week’s topic suggestion, animals that mate for life or develop pair bonds! Happy Valentine’s Day!

Further reading:

Wisdom the albatross, now 70, hatches yet another chick

The prairie vole mates for life:

Swans mate for life:

The black vulture also mates for life:

The Laysan albatross:

Wisdom the Laysan albatross with her 2021 chick (pic from the link listed above). I hope I look that good at 70:

Dik-diks!

The dik-dik nose is somewhat prehensile:

The pileated gibbon (and other gibbons) forms pair bonds:

Show transcript:

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

Last February Ella and her son Jack suggested a Valentine’s Day topic. I already had the February episodes finished last year, but this year Valentine’s Day falls on a Monday and that just seems too perfect to pass up. So thanks to Ella and Jack, we’re going to learn about some animals that are monogamous.

Valentine’s Day falls on February 14th and in many European cultures is a day celebrating love and romance. It also falls at the very beginning of spring in the northern hemisphere, when many animals start finding mates.

Different species of animal have different relationships. Some animals are social, some are solitary. Every species is different because every species has slightly different requirements for reproducing due to different habitats, foods, how much care the babies need, and so forth.

There are different types of monogamy among animals and it can get complicated, just as it’s often complicated in people, so I’m going to simplify it for this episode into two categories: animals that mate for life and animals that form pair bonds. Animals that mate for life, meaning the male and female seek each other out every mating season to have babies together, don’t necessarily spend all their time together outside of mating season. Animals in pair bonds spend a lot of their time together, but they don’t always exclusively mate with each other. But some animals do both.

For instance, the prairie vole. This is a little rodent that lives in dry grasslands in central North America, in parts of the United States and Canada. It’s about the size of a mouse with a short tail although it’s more chonky than a mouse, like a small dark brown hamster. It spends most of its time either in a shallow burrow it digs among grass roots or out finding the plant material and insects it eats by traveling through aboveground tunnels it makes through densely packed plant stems. It lives in colonies and is a social animal most of the time, and the male in particular is devoted to his mate. He’s so devoted that once he’s found a mate, he will even drive away other females who approach him.

The only time the prairie vole isn’t social is during mating season, which is usually twice a year, in fall and in spring. At that time, mated pairs leave the colony and find a small territory to have their babies. The pair spends almost all their time together, grooming each other, finding and sharing food, and building a nest for the babies. When the babies are born, both parents help care for them.

The male prairie vole mates for life. Most of the time “mating for life” means that if one of a pair dies, the other will then find a new mate. But for the male prairie vole, if his mate dies, he stays single for the rest of his life. He also shows behaviors that are similar to grief in humans. The female prairie vole is a little more practical and although she also grieves if her mate dies, she’ll eventually find another mate. Researchers who study prairie voles have discovered that the hormones found in mated pairs are the same as those in humans who are in love.

That’s so sweet, and I wish I didn’t have to talk about the voles dying. I think the opposite of love isn’t hate; the opposite of love is grief. It’s okay to be sad even for a long time when someone you love dies or moves far away, or if your own pair bond doesn’t work out. It’s also okay to find happy moments even when you’re grieving. Life is complicated. Also, just going to point out, devoted as they are to each other, sometimes a prairie vole will mate with someone besides their own mate.

One bird that’s famous for being monogamous is the swan. It mates for life and also forms pair bonds. These pair bonds form while the swans are still young, and the young couples basically just hang out together long before they’re old enough to have babies. It’s no wonder pictures of swans appear on so many wedding invitations and Valentine’s day cards. It helps that they’re beautiful birds too. The black vulture also mates for life but no one puts vultures on a wedding invitation. Also, swans sometimes split up and find new mates. Things don’t always work out with a pair bond, even for swans.

Another large, beautiful bird that mates for life is the albatross, but it doesn’t form a pair bond. Most of the time the albatross is solitary, traveling thousands of miles a year as it soars above the open ocean, looking for squid, small fish, and other food near the surface of the water. But once a year in some species, and once every two years in other species, albatrosses return to their nesting grounds and seek out their mate.

Albatrosses live a very long time so are really picky about who they choose as a mate. Once a pair forms, they develop a complicated, elegant dance to perform together. Each couple’s dance is unique, which helps them find each other in a crowded nesting colony when they haven’t seen each other in a couple of years.

The oldest wild bird in the world that we know of is a Laysan albatross named Wisdom. She was tagged by scientists in 1956 when she was at least five years old already, and as of 2021 she was still healthy and producing healthy chicks with her mate. Her leg tag has had to be replaced six times because she’s outlasting the material used to make the tags.

The Laysan albatross is a smaller species of albatross, with a wingspan of not quite 7 feet, or over two meters. Its body is mostly white, although its back is gray, with black and gray wings and a dark smudge across the eyes that looks very dramatic. It spends most of the time in the northern Pacific between the west coast of North America and the east coast of Asia, but it only nests on 16 tiny islands. Most of these are part of the Hawaiian islands with a few near Japan, but recently new breeding colonies have been spotted on islands off the coast of Mexico.

Wisdom the albatross is estimated to be at least 70 years old as of 2021 and she’s raised 30 to 36 chicks successfully. Because of her age, which is old even for an albatross, she may have outlived her first mate and taken another. She’s been with her current mate since at least 2012.

Albatrosses only lay one egg during nesting season. Both parents help incubate the egg and feed the baby when it hatches. It takes two or three months for the egg to hatch, depending on the species. Once the egg hatches, it’s at least another 5 or 6 months before the chick is old enough to leave the nest and care for itself, and in some species this is as much as 9 months. This means a big time and energy investment for both parents.

Albatrosses don’t reach sexual maturity until they’re at least five years old. Birds younger than this still join the breeding colony and practice their dance moves for when they’re old enough to choose a mate.

Pair bonding and mating for life are common in birds, rare in amphibians, reptiles, and fish, and surprisingly rare in mammals. One mammal that both mates for life and forms a pair bond is a tiny antelope called a dik-dik.

The dik-dik lives in parts of eastern and southern Africa and is barely bigger than a rabbit, which it somewhat resembles in shape. It stands less than 16 inches tall at the shoulder, or 40 cm, although its back and rump are arched and rounded and so are actually higher than the shoulder. Females are usually larger than males, while only males have horns. The horns arch back from the head but because the male has a tuft of long hair on the top of his head, and because the horns are only about 3 inches long at most, or 7.5 cm, they can be hard to see.

The dik-dik has an elongated snout that’s somewhat prehensile. It lives in hot areas without much water, so it gets most of its moisture from the plants it eats. Most of the time hot weather doesn’t bother it, but on exceptionally hot days it can cool down by panting through its long nose. Its nose is lined with blood vessels close to the surface and it has special nose muscles that allow it to pant quickly. Air moving over the blood vessels helps cool the blood.

Because pretty much everything eats the dik-dik, traveling long distances to find a mate is dangerous. Once the dik-dik finds a mate, they stay together for life in a small territory and spend most of their time together. Females give birth to one fawn twice a year, and the fawn no longer needs its parents at about 7 months old. Parents drive away their grown offspring, who leave to find a mate and territory of their own.

Humans, of course, strongly pair bond because we’re such intensely social creatures, and many people choose a partner and stay with them for life. Then again, we don’t always. Surprisingly, our closest living cousins, the great apes, are also very social, but they don’t typically form pair bonds and females may mate with different males.

The gibbon, which is a lesser ape instead of a great ape, does often form long-lasting pair bonds. We’ve talked about various species of gibbon in previous episodes. Gibbons are the apes that sing elaborate duets with their mates, with their children sometimes joining in as a chorus.

Here’s a pair of pileated gibbons singing together. The female is named Molly and was in a rehabilitation center after being injured, but she found a wild mate while she was recovering:

[gibbons singing]

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 260: Danger! Newts!

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Thanks to Enzo for suggesting this week’s topic, newts from least dangerous to most dangerous!

Further reading:

One snake’s prey is another’s poison

The Corsican brook salamander is not toxic (photo by Paola Mazzei, from iNaturalist):

The smooth newt is a little bit toxic (photo by Fred Holmes and taken from this site) – this is a male during breeding season:

The Hong Kong warty newt has an orange-spotted belly and is toxic:

The chonky Spanish ribbed newt will stab you with its own toxin-covered bones (photo by Eduardo José Rodríguez Rodríguez, taken from this site):

Yeah maybe don’t touch the Japanese fire belly newt if you don’t need to:

Warning! Do not eat the California newt:

The safest newt to handle is this toy newt. I really want one:

Show transcript:

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

This week’s topic is a suggestion from Enzo, who wants to learn about newts “from least dangerous to most dangerous.” There are at least 60 species of newt known with more being discovered every year, but I’ll do my best to hit the highlights.

A newt is a type of salamander, specifically a semi-aquatic salamander in the subfamily Pleurodelinae. All newts are salamanders but not all salamanders are newts. Newts live throughout much of the northern hemisphere, including northern Africa and the Middle East, Eurasia, and North America.

Female newts lay their eggs in freshwater, usually attaching them to vegetation or in little crevices in rocks. A few weeks later, the eggs hatch into larvae with external gills. The larvae are called tadpoles like frog larvae, and they mostly eat algae and tiny insects. They metamorphose over several months just like frogs do when they develop from tadpoles, but where frogs develop their hind legs first, newt tadpoles develop front legs first. The newt tadpole finally absorbs its gills and grows lungs instead, at which point it emerges from the water as an immature newt called an eft. Efts are juvenile newts and live exclusively on land, although like other amphibians they have to keep their skin damp so you’ll usually find them in leaf litter and under rotting logs. Efts that live in North America return to the water when they become full adults, but most newts in other parts of the world stay on land the rest of their lives except during breeding season. Efts and adult newts eat worms, insects and insect larvae, slugs, frog tadpoles, and any other small animals they can catch.

The Corsican brook salamander is a type of newt that lives on the island of Corsica in the Mediterranean Sea. It grows about five inches long at most, or 13 cm, and is brown or olive-green, sometimes with a mottled pattern of orange or red on its back. It’s an exception to the rule that newts outside of North America usually live their adult lives on land. Not only does the Corsican brook salamander live in freshwater most of the time as an adult, it doesn’t even have working lungs. It spends most of its time in fast-moving streams and rivers in higher elevations, where it absorbs oxygen from the water through its skin.

As Enzo undoubtedly knows, many newts produce toxins. This is why it’s not a good idea to handle a newt, or any other amphibian for that matter, unless you’re absolutely certain it’s a species that’s not toxic. In most cases, a newt’s toxin won’t hurt you if it just touches your skin, but if it gets in a cut or if you have some of the toxin on your finger and then rub your eye or put your finger in your mouth, the toxin can make you really sick. Some newts are even deadly.

The Corsican brook salamander we just talked about is not toxic, so we’ll call it the least dangerous newt. The smooth newt, on the other hand, produces a relatively mild toxin. You’d have to actually eat a bunch of smooth newts to get sick from its toxins, and why are you eating newts at all? Stop that immediately and have a banana instead.

The smooth newt lives throughout much of Europe and parts of Asia. It grows just over 4 inches long, or 11 cm, and most of the time it’s brown with darker spots. The male also has a bright orange stripe on his belly. During breeding season, though, the male develops a wavy crest down his spine and brighter colors. Both males and females move into the water during breeding season, so both males and females develop tail fins on the top and bottom of their tails to help them swim.

The males of many newt species develop brighter colors and crests during breeding season to attract females. In the case of the Hong Kong warty newt, in breeding season the male develops a white stripe on his tail. He attracts the attention of females by wagging his tail in the water, where the white stripe shows up well even in dim light. The Hong Kong warty newt lives in Hong Kong and grows up to 6 inches long, or 15 cm. It’s brown with orange patches on its belly and its skin appears bumpy like the skin of an orange. If it feels threatened, it sometimes rolls onto its back and pretends to be dead, which not only may deter some predators, it shows off the bright orange markings on its belly. This signals to a potential predator that this newt is toxic, and another thing it does when it plays dead is secrete toxins from its skin. In other words, don’t bite this newt or touch it. It’s also a protected species in Hong Kong so you shouldn’t be trying to eat it anyway. Its eggs are toxic too.

Some newts deliver their toxins to potential predators in a way you might not expect. If an animal tries to bite the Spanish ribbed newt, it secretes toxins from special glands on its sides and then pushes the sharp points of its own ribs out through the tubercles where the poison glands are located. The pointed ribs become coated with toxins as they emerge and are sharp enough to stab a predator right in the mouth. The toxin causes severe pain when injected and can even cause death in small animals. The newt itself isn’t injured by this process, which it can do repeatedly whenever it needs to. Newts, like all amphibians, heal extremely quickly.

The Spanish ribbed newt lives in the southern Iberian Peninsula in Europe and Morocco in northern Africa. It’s larger than the newts we’ve talked about so far, growing up to a foot long, or 30 cm. It’s dark gray with rusty-red or orange spots on its sides, one spot per poison gland. It actually spends most of its adult life in the water and especially likes deep, quiet ponds and wells.

Finally, we’ve reached the most dangerous newt in the world. I’m nominating two newts for this honor because they both secrete the neurotoxin tetrodotoxin, which we’ve talked about before. It’s the same kind of toxin found in pufferfish and some frogs. The toxin can irritate your skin even if you only touch it, and if a little of the toxin gets into a scratch or cut, it can cause numbness, shortness of breath, and dizziness. If you accidentally swallow any of the toxin, you can die within six hours. There’s no antidote.

Our two most dangerous newts are the Japanese fire belly newt and the California newt. The Japanese fire belly newt grows about 5.5 inches long, or 14 cm, and lives in parts of Japan in ponds, lakes, and ditches. It has pebbly skin and is brown or black with red speckles, but its belly is bright orange or red. The California newt has slightly bumpy gray or gray-brown skin on its back but a bright orange or yellow belly. It can grow up to 8 inches long, or 20 cm. It lives in parts of California, especially near the coast and in the southern Sierra Nevada Mountains.

The reason the California newt has such a potent toxin is that its main predator, the common garter snake, has a great resistance to the toxin. Only the most toxic newts are more likely to survive if a garter snake grabs it, and only the most resistant snakes are more likely to survive eating it. It’s a predator-prey arms race that’s been going on for at least 40 million years, resulting in a newt that is boss fight level toxic to most predators but just barely ahead of the game when it comes to garter snakes. It’s likely that something similar has occurred with the Japanese fire belly newt.

If you live in the areas where these toxic newts also live, be especially careful with your pets. Keep your dog on a leash so you can be sure it doesn’t try to bite or play with one of these newts. Some people actually keep the Japanese fire belly newt as a pet, but obviously if you do this you need to be extremely careful, especially if you have pets or small children. Maybe you should get a toy newt instead.

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 258: Sable and Sable Antelope

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A big birthday shout-out to Penelope this week! Thanks to Isaac for this week’s topic suggestion. We’re learning all about the sable and sable antelope!

Further reading (mostly for the pictures since there’s not much content otherwise):

Woman Rescues This Sable from Becoming Someone’s Coat

Further watching:

Kruger Park, Season 15 – this one is about some sable antelope bulls fighting

Fuzzy sable face:

Sable:

Sable antelopes:

A sable antelope growth chart. I find this really interesting. NERD:

Show transcript:

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

This week we’ve got an interesting theme, with both the theme and the animals suggested by Isaac. But first, we have a birthday shout-out!

Happy birthday this week to Penelope, whose birthday is on January 15th! I hope you have the best birthday ever!

Isaac suggested the sable, which is a type of mustelid, or weasel and ferret relation, and also suggested the sable antelope! It’s the sable episode.

The word sable means black or a rich dark brown, but most of the time it’s used to refer to the fur of an animal called the sable. The fur was so highly prized in Europe and Asia that the color of the animal’s fur was used as the name of the animal itself, and has been borrowed to refer to a specific coloration of other animals like cats and dogs.

The animal called the sable is common throughout parts of Asia, especially Siberia, China, and northern Mongolia. It lives in forests and mostly hunts by sound, and will eat just about anything it can find. This includes small animals like hares, rodents, birds, and even other species of mustelid, but it will also eat carrion, berries, fish, insects, snails and slugs, and occasionally it will even manage to kill a small bovid called a musk deer. The musk deer isn’t actually a deer but is more closely related to goats and antelopes. It can stand over two feet tall at the shoulder, or 70 cm, and the male has fang-like tusks instead of antlers or horns.

For an animal that sometimes kills and eats musk deer, the sable isn’t very big. It’s long and slender like other mustelids and measures nearly 2 feet long, or 56 cm, not counting its tail, which can add another 5 inches, or 12 cm. Females are a little smaller. It’s brown all over, usually dark brown but sometimes lighter depending on where it lives, with a pale patch on its throat. It has large fox-like ears and a somewhat fox-like or cat-like face but with smaller eyes. Its legs are short but that doesn’t stop it from covering long distances every day to find enough food, more than seven miles in some cases, or 12 km.

The sable is crepuscular, meaning it’s most active during dawn and dusk. When it’s not out hunting, it sleeps in a burrow it digs among tree roots, often lined with leaves and dry grass so it’s more comfortable and warmer. The exception is during mating season when the sable is more likely to be out during the daytime. Males fight each other during this time, and when a female is deciding whether she likes a male, she and the male will play-fight and chase each other.

One unusual thing about the sable is that even though mating season is usually in summertime, and even though it only takes about a month for the babies to develop inside the mother before they’re born, the babies are born in spring. Since the sable doesn’t have access to a time machine, something else is going on.

It’s called delayed implantation or embryonic diapause, where the mother’s egg is fertilized but then stays dormant for a time before it attaches to the uterine wall and starts developing into an embryo and ultimately a baby ready to be born. This allows babies to be born at a time of year when there’s plenty of food. In the sable’s case, the fertilized eggs don’t implant for 8 months.

Sables aren’t the only mammals that practice delayed implantation. A lot of mustelids do, as well as bears, seals, armadillos, and many others. A slightly different variety of delayed implantation only happens when the mother already has a baby that’s nursing, meaning she’s still producing milk. That’s hard on the body, so in some mammals, including some rodents and marsupials, the fertilized egg waits to implant until the mother is no longer producing milk. That way the mother has more resources available to nourish the growing embryo instead of having to divide her energy between her developing embryos and her already-born babies. In other mammals, including humans, a nursing mother doesn’t usually produce eggs to be fertilized until she’s stopped producing milk for her baby.

A female sable usually has two or three babies in a litter but sometimes more. The babies are born with a little bit of fuzzy hair to help keep them warm, but like puppies and kittens they’re born with their eyes sealed shut. It takes about a month for their eyes to open. The mother weans them when they’re about two months old but continues to take care of them, first by regurgitating food for them to eat, then by teaching them how to hunt and forage for themselves.

The sable’s fur is exceptionally soft and beautiful, and as a result it’s been killed for its fur for centuries and has always been expensive to buy. One Russian population is jet black with a white tip to each hair, which was even more highly prized than the rest. But the best way to experience the beautiful fur of a sable is by petting a live one, not the skin of a dead one. Some people have started keeping sables as pets, although they’re not actually domesticated and can be difficult or even dangerous to keep.

Next, another beautiful non-domesticated animal is the sable antelope. It lives in forested savannas in parts of eastern and southern Africa. There are four subspecies, the largest of which is the giant sable antelope. That makes it sound enormous but it’s only a little bigger than other subspecies, and is critically endangered. In fact, the giant sable antelope was suspected of having gone extinct during a terrible civil war in Angola, which is the only place in Africa where it lives. Fortunately a herd of them was caught on camera trap in 2004, and the giant sable antelope is now protected.

Sable antelope cows give birth to one baby during the rainy season, which varies depending on where they live. The calves are light brown or pale reddish-brown but as they grow older, their fur becomes darker. Mature females are usually dark brown but adult males are black. Adults and older calves also have white patches on the face, belly, and rump.

The sable antelope has a short tail with a little tuft at the end, and it also has a short mane that usually stands upright like a donkey’s mane. Males are bigger than females, standing some 4 and a half feet tall at the shoulder, or 1.4 meters.

Both males and females have horns, though. Antelopes are bovids, which means they have true horns like cattle and goats, not antlers like deer that are shed every year. The sable antelope’s horns are really impressive, too. They’re dark gray or black and arch up and back from the head like really big goat horns. A female can have horns up to 3 and a half feet long, or 102 cm, while a male can have horns 0ver 5 feet long, or 165 cm. That’s right, his horns can be longer than he is tall. Sable antelopes are so spectacular that when you think of an antelope, you probably think of an animal that has horns like this.

Unfortunately, those horns have caused the sable antelope to be a target for big game hunters who want the horns as a trophy. These days, though, the biggest threat is habitat loss as humans fence their grasslands to graze livestock.

During the rainy season, the sable antelope lives in small herds of up to 30 females and their young, who share a territory with a single bull. The herd is led by the oldest females who know where the best places are to graze and find water. When the herd moves, the male usually follows right behind to make sure everyone stays together.

The sable antelope eats tree leaves and some kinds of grass, and spends the hottest parts of the day lying down and chewing its cud because, like other bovids, it’s a ruminant. The calves are always in the middle of the resting herd and the adults lie facing outward so they can watch for danger and meet it with their horns. When the adults are moving around to graze, young calves stay in a group called a creche, watched over by a few adults.

During the dry season when there’s not as much to eat, herds will come together to graze in the best pastures with access to water. When young males mature, the older male drives them away from the herd to fend for themselves. Young bulls often form small bachelor herds or may be solitary.

When a bull challenges another bull in an attempt to take control of his territory, they fight with their horns, although they don’t usually injure each other. The sable antelope also uses its horns to fight off and sometimes even kill predators like lions and leopards.

This is the only reliable audio I could find of a sable antelope. There’s a link to the original video in the show notes. The sound is of a bull who’s stuck in the mud, although he later manages to get out.

[sable antelope 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 247: Shapeshifters

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Happy Halloween! Let’s learn about some shapeshifters of folklore, including the werewolf and kitsune (thanks to Joel, Pranav, and Emma!), and a real-life shapeshifter.

Don’t forget the Kickstarter, as if I’d let you forget it: https://www.kickstarter.com/projects/kateshaw/beyond-bigfoot-and-nessie

Further reading:

Folklore and Mythology

Breeding Butterflies

Further listening:

MonsterTalk (note: sometimes there’s adult language or really scary themes)

Sandman Stories Presents podcast

A death’s head hawkmoth, looking spooky:

A death’s head hawkmoth caterpillar, not looking spooky at all:

Show transcript:

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

It’s Halloween week and that means we need to talk about a truly spooky monster! Both Joel and Pranav suggested the werewolf a while back and Emily suggested the kitsune [kee-tsoo-neh], so let’s learn about shapeshifters and were-animals of all kinds. “Wer” is an Old English word that just means “man,” and just to get confusing, the word “man” used to refer to any person. The word “wif” referred to a woman, with wifman actually meaning woman. From those words we get the modern uses of wife, woman, and man, while “wer” is obsolete except in werewolf.

Let me derail myself from talking about language by reminding you about our Kickstarter! It ends pretty soon, on November 5, 2021, so if you’ve been thinking about backing the project this would be a great time. It’s to help me publish a book all about mystery animals, called Beyond Bigfoot and Nessie: Lesser-Known Mystery Animals from Around the World. The book has a foreword by Blake Smith of MonsterTalk, the science show about monsters, and if you don’t already listen to that podcast, it’s a whole lot of fun and informative too. Thanks to everyone who has already backed the project!

Now, Happy Halloween and on to the spookiness!

The important first question we need to answer is if werewolves really exist.

No. They do not exist outside of folklore and fiction, and I’ll explain why later so you don’t ever have to worry about werewolves or any other shapeshifters. But first, let’s learn what werewolves and kitsunes are.

Werewolves are supposed to be people who can turn into wolves. Depending on the story, this can happen when the person wants to turn into a wolf or it can happen during the full moon whether the person wants to be a wolf or not. Sometimes the person has a magical wolfskin or some other item that they put on in order to transform. Sometimes they have to cast a magic spell, but sometimes it’s a curse that someone else has inflicted on them. Some stories say that the only way to kill a werewolf is by shooting it through the heart with a silver bullet, especially one that’s been blessed by a priest.

The werewolf is mainly from European folklore, where for many centuries all werewolves were also supposed to be witches. Until about the 18th century in some areas, if someone accused you of being a werewolf, you could be put on trial as a witch. Lots of people were convicted of witchcraft and killed during waves of witch-hunts in various parts of Europe. Most of the people accused were women, especially elderly women, especially women who were widowed or single, especially women who owned land that someone else wanted. Hmm.

The kitsune is a creature of Asian folklore, especially from Japan, that’s basically a fox that can work magic. It’s sometimes said that all foxes can turn into humans if they want, especially older foxes. The older and more powerful a kitsune is, the more tails it’s supposed to have, up to nine. Kitsunes sometimes play tricks on people but they can also act as guardians and friends.

About the same time that old ladies were being accused of being werewolves in Europe, though, around the 15th to the 18th centuries, something similar happened in Japan. People were much more superstitious during this time and thought the kitsune was a dangerous goblin-like creature that could possess people and make them act like animals. These days the kitsune is back to being considered mostly a friendly trickster.

Werewolves weren’t the only shapeshifters in the folklore of Europe, although they were the most common. A German story collected in 1879 is about someone who could transform into a fox using an item called a strap.

“In the village of Dodow near Wittenburg there lived an old woman who possessed a fox strap. With its help she could transform herself into a fox, and thus her table never lacked for geese, ducks, and all kinds of poultry.

“Her grandchild knew about it, and one day when the schoolmaster was talking about magic in the school, the child told about the fox strap, and the next day brought it to school.

“The schoolmaster took it into his hand and unintentionally approached his head with it. Suddenly he was standing before the children, transformed into a fox. They broke out with a deafening noise. This so frightened the little schoolmaster that he jumped out the window with a single leap.

“He ran to the hill that lay near the village and there built himself a den.

“One day a great hunt was organized, and our fox was among those pursued by the huntsmen. A bullet hit him, and suddenly a schoolmaster was lying there before the bewildered huntsman. The bullet had struck the fox strap and ripped it apart.”

Witches were also supposed to be able to transform themselves into hares, cats, dogs, even geese in European folklore. In other parts of the world, though, folklore is full of people who can turn into different animals, and the animals are always ones local to the area. In various parts of Africa there are stories of people who transform into hyenas, leopards, and lions, while in various coastal areas of the world there are stories of seals, orcas, dolphins, and other water animals that can transform into people or which are humans in disguise.

The nagual is a story from many places in Mesoamerica, dating back to the ancient Aztecs and Olmecs and other people who lived in what is now Mexico and parts of Central and South America. The nagual was supposed to be someone who could shapeshift into a jaguar. Some people today still believe in the nagual the same way some people still believe in werewolves, and like many other shapeshifters it’s often connected with witches. Modern nagual stories are about witches who can transform into various animals at night, including owls, bats, turkeys, pumas, and even wolves. In some stories they’re thieves and murderers, while in other stories they help people.

Of course, not all folktales about shapeshifters are spooky. Sometimes they’re just meant to be funny, like this story from India.

Once there was a boy who herded buffaloes, and he noticed that at noon every day a dog would visit some nearby pools of water in a little valley. One day he hid to watch the dog. To his surprise, when the dog reached the water, it took its skin off and out stepped a beautiful young woman! She bathed in the pool, then put her dog-skin back on and left. The boy followed her to see what house she went to, then went back to watching his buffaloes.

Later that year the boy’s parents decided it was time for him to marry and began to look for a wife for him. But he told them he wanted a dog as his wife and even had a particular dog picked out. Everyone laughed at him, but he was determined to marry the dog and so his parents agreed.

The wedding took place and that night the new bridegroom pretended to fall asleep, and when the dog got up he watched to see what she would do. She took her dog-skin off and started to leave the house, but the groom jumped up and threw the dog-skin on the fire, where it burned up. His wife remained in her human form and they lived happily ever after.

Here’s another story, this one from Korea and published in 1911. Once a very poor old couple lived on the edge of a town, where they grew just enough rice to keep from starving. The old man caught fish to sell for extra money, but one day when he went to the lake, it was almost dried up and all the fish were gone. In the middle of the lake was a giant frog.

The old man shouted at the frog, “How dare you drink up the lake and eat up all the fish!” But the frog said, “You’ll thank me for it one day. Take me home and let me live in your house, and you’ll see how lucky you’ll be.”

The old man didn’t know what to do. Without the water from the lake, his rice would die, and without the fish from the lake, he had nothing to sell. He took the giant frog home.

The old man and his wife gave the frog the best room in their small house and the best food they had. In return, the frog turned out to be a very pleasant lodger and would talk and laugh with the couple long into the night, telling stories and singing songs.

After a week, the frog said he needed to take a wife, but she had to be beautiful and of noble birth. The old man went to the town’s magistrate, whose youngest daughter was the most beautiful woman in the land, and explained that a giant frog would like to marry the magistrate’s daughter.

The magistrate laughed at first, but when he realized the old man was serious, he ordered him to be beaten. But immediately, hail began to fall from the sky—first tiny hailstones, then bigger and bigger ones. The magistrate hastily changed his mind and said his daughter could marry the frog, and the hail stopped.

In this time and place, a bride went to her wedding with her eyes closed and painted over with wax so she couldn’t see her husband until after the ceremony. Imagine the bride’s horror, after the wax was removed and she took her first look at her new husband, when she discovered he was a giant frog! The bride was furious, but the frog said, “You’ll be glad you married me. Will you take these scissors and loosen the skin of my back? It’s too tight and hurts me.”

The bride was so angry that she took the scissors and cut the frog’s skin open all the way down his back. Then, to her astonishment, he wriggled right out of his skin and out stepped a handsome prince wearing fine silk clothes. He had been enchanted and the spell could only be broken when he married a human woman. He and his wife lived happily ever after, and the poor old couple who had helped him were given all the riches they desired and lived in a palace to the end of their days.

I could keep going forever, because there are a whole lot of stories about shapeshifters from around the world. If you want more folktales, I recommend the podcast “Sandman Stories Presents.” Each episode is another folktale. It’s really interesting and the host’s voice is soothing if you need a podcast to help you fall asleep.

Outside of folklore and mythology, shapeshifters aren’t real. To understand why, we have to look at a very different animal, the butterfly—or, since this is a Halloween episode and most moths are nocturnal, the moth. Let’s learn about an especially Halloween-y moth, the African death’s-head hawkmoth. It gets its name from a pattern on its back that looks sort of like a human skull. Its upper wings are black and its lower wings are usually yellowy-orange. Its wingspan is as much as 5 inches across, or 13 cm. It lives in parts of Africa and migrates to Europe for the summer.

The deaths-head hawkmoth caterpillar can grow up to 6 inches long, or 15 cm, and has a curved horn-like structure basically on its butt. After it hatches, it spends the next month or two eating leaves, especially the leaves of potato and tomato plants. During this time it will go through five stages of development, called instars, where it sheds its skin and grows larger. Finally, the caterpillar burrows into the ground and forms a little nesting chamber in the dirt. For the next few weeks it just sits in the chamber while moisture evaporates from its body and it forms a hard shell-like structure called a pupa.

Inside the pupa, the caterpillar transforms into a moth by breaking down its own body with digestive juices. The resulting goo of undifferentiated cells reforms into a moth body, a process that takes weeks. Finally the newly formed moth emerges from the shell of its pupa and from the ground, climbs onto a leaf or twig, and hangs there for a little while as its wings uncrumple and extend to their full size.

The transformation of a moth or butterfly, or other insects that go through the same process, is astounding and not fully understood. What we do know is that it takes massive amounts of energy. A caterpillar eats all the time in order to store up energy to metamorphose into a moth or butterfly. If there was an easier way, for instance if a caterpillar just had to cast a magic spell or put on a mothskin coat to transform, they would do it the easy way. But they don’t, because this is the most efficient way to transform from one body to another that nature has developed. It takes weeks, it’s messy and dangerous because the animal is helpless the whole time, and it only happens once in an insect’s lifetime.

So that’s that. Werewolf movies are a lot of fun to watch, especially this time of year, but you don’t have to lie awake at night afterwards worried that a werewolf is going to bite you.

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

Thanks for listening!

Episode 243: Bats and Rats

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Don’t forget the Kickstarter, as if I’d let you forget it: https://www.kickstarter.com/projects/kateshaw/beyond-bigfoot-and-nessie

Let’s pre-game Halloween and monster month with an episode about some Halloween-y bats and rats! Thanks to Connor for the suggestion!

Further reading:

Meet Myotis nimaensis

Hyorhinomys stuempkei: New Genus, Species of Shrew Rat Discovered in Indonesia

Fish-eating Myotis

The orange-furred bat is Halloween colored!

The hog-nosed rat has a little piggy nose and VAMPIRE FANGS:

The fish-eating bat has humongous clawed feet:

The crested rat does not look poisonous but it is:

Show transcript:

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

This week we’re getting ready for October by talking about a bat suggested by Connor, along with another type of bat and two rats. It’s the bats and rats episode ushering us into Monster Month with style!

Don’t forget that our Kickstarter for the Strange Animals Podcast book goes live in just over a week! I know, it hasn’t even started yet and I’m already shouting all about it, but I’m excited! There’s a link in the show notes if you want to click through and bookmark that page.

Also, I have a correction from our recent squirrel episode. Nicholas wrote to let me know that vitiligo isn’t actually a genetic condition, although some people are genetically slightly more likely to develop it. I think that’s what caused my confusion. Vitiligo can be caused by a number of things, but it’s still true that you can’t catch it from someone. I’ll include a more in-depth correction in next year’s updates episode.

Okay, let’s start this episode off with Connor’s suggestion. Connor told me about a newly discovered bat called Myotis nimbaensis, and it’s not just any old bat. It’s a Halloween bat! Its body is orange and its wing membranes are black. It’s called the orange-furred bat and it lives in the Nimba Mountains of Guinea in West Africa.

The orange-furred bat was only discovered in 2018, when a team of scientists was exploring abandoned mine shafts in the mountains, looking for the critically endangered Lamotte’s roundleaf bat. The team was surveying the bats in cooperation with a mining company and conservation groups, because they needed to know where the bats were so the old mine shafts could be repaired before they fell in and squished all the bats.

Then one of the team saw a bat no one recognized. It was orange and fluffy with big ears and tiny black dot eyes, and its wings were black. They sent a picture of the bat to an expert named Nancy Simmons, and Dr. Simmons knew immediately that it was something out of the ordinary. Sure enough, it’s a species unknown to science. The team described the bat in 2021.

Next, let’s talk about a rat. It was also discovered recently, in this case in 2013 and described in 2015. It’s usually called the hog-nosed rat. It lives in a single part of a single small island in South Asia, specifically in North Sulawesi, Indonesia. This is one of the same places where the babirusa lives, if you remember episode 218.

The hog-nosed rat is a rodent but it’s not actually that closely related to other rats and mice. It’s even been assigned to its own genus. It’s a soft brown-gray on its back and white underneath, with big ears, a very long tail, and a pink nose that does actually look a lot like a little piggy nose. Its eyes are small but its incisors are extremely long and sharp. In fact, they look like vampire fangs!

In 2013, a team of scientists was studying rodents living in the area. To do this they would put special traps out at night and check them in the morning. This isn’t a regular rat trap that kills rats, of course, but a box that keeps the rodent safe inside so it can be examined before being released again. One day they checked a trap and inside was a rodent no one recognized. Surprise rat!

So, what does the hog-nosed rat eat with those vicious fangs? Earthworms and beetle grubs! Terrifying, I know.

Next, let’s learn about another bat, Myotis vivesi. It’s called the fish-eating bat or the Mexican fishing bat. It lives around the Gulf of California on the west coast of North America, mostly on small islands. It’s brown on top, white or cream-colored underneath, and it has big ears because it’s a bat. Almost all bats have big ears.

Fish eating is unusual in bats, and marine fish eating is even more unusual. Only one other species of bat, the fisherman bat of Central and South America, catches marine fish regularly, but the two species belong to completely different families. The Mexican fishing bat’s closest relatives don’t eat fish at all.

Because it lives exclusively around the ocean and feeds mostly on fish and crustaceans, although it will occasionally eat insects and algae, the Mexican fishing bat has other unusual adaptations. It drinks seawater instead of fresh water, for one thing. During the day it hides in crevices in rocks, sometimes in cliffs but more often in the rocky ground. It actually wriggles its way about three feet underground, or a meter, where it’s dark and cool.

Why are we talking about this particular bat in our pre-October episode? Because it has humongous feet with long, pointy claws. The bat itself is only about 5 ½ inches long, or 14 cm, but its feet are almost an inch long, or 2.5 cm. It uses its big feet to snag tiny fish out of the water.

We’ll finish with another rodent, the maned rat, or African crested rat. It doesn’t actually look much like a rat, since its tail is furry and it has a short, blunt muzzle sort of like a porcupine’s face. It’s mostly gray and black with white-tipped hairs that make it look frosty, and it has a crest of longer hairs along its back. It also has white stripes along its sides. It grows about 14 inches long, or 36 cm, not counting its thick, furry tail.

The crested rat mostly eats plants, especially fruit and leaves, but will sometimes eat insects and meat too. Its stomach is divided into multiple chambers and is more like a ruminant’s stomach than a rodent’s, which allows it to use a form of foregut fermentation to digest plant material more efficiently.

Also, the African crested rat is POISONOUS.

The crested rat chews on the bark of the poison arrow tree, which contains toxins that can kill most animals. The crested rat isn’t affected by the toxins, though. After it chews the bark, it licks the long hairs of its crest, which are unusually absorbent. The hairs absorb the poison-filled spit so that any animal that tries to take a bite of African crested rat gets sick or even dies. It probably also tastes terrible but that’s just a guess.

The poison arrow tree is a type of milkweed, and most plants in this family contain toxins. North American milkweed plants are the ones that monarch butterfly caterpillars eat, and the caterpillars absorb toxins from the milkweed that keep birds and other animals from eating them. Researchers aren’t sure how the crested rat keeps from getting sick from the toxins, but one theory is that its stomach contains specialized bacteria that break down the toxins.

If an African crested rat feels threatened, it will raise its crest of long hairs. The crest actually parts down the middle of the back, exposing the white section of the hair and warning predators away.

In case you’re too scared by this poisonous fuzzy rodent, you can relax knowing that the African crested rat is a sociable animal that makes purring sounds while it grooms its family members. Just don’t lick it.

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

Thanks for listening!

Episode 242: Snakes with Nose Horns

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Check out our Kickstarter pre-launch page!!

Thanks to Max for suggesting the rhinoceros viper! We’ll learn about that one and several other snakes with nose horns this week.

The rhino viper, AKA the butterfly viper because of its beautiful colors and pattern:

The rhino viper has nose horns (photo by Balázs Buzás):

The West African Gaboon viper (Bitis rhinoceros), AKA the other rhino viper:

The rhinoceros snake, AKA the Vietnamese longnose snake (photo taken by me! That’s why it’s kind of blurry!):

The nose-horned viper is a beautiful snake:

Show transcript:

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

Just a reminder about our Kickstarter for the Strange Animals Podcast book! Check the show notes for a link if you want to look at the preliminary cover and maybe bookmark the page for when we go live in just two weeks!!

This week we’ll learn about the rhino viper, which was suggested by Max, who at the time was almost eight years old but that was so long ago I bet Max is eight now or maybe nine or ten. Maybe thirty.

The rhinoceros viper lives in forests in parts of western and central Africa, and can grow three and a half feet long, or 107 cm. It’s a heavy chonk of a snake but it’s beautifully colored, with big triangular blotches and smaller markings of red, yellow, black, and blue or green. If you look at one on a white background it stands out, but on the forest floor where it lives, with dead leaves and plants all around, it blends right in. It has rough scales that make it look bristly, called keeled scales. The rhino viper’s scales are so strongly keeled that they can cut your hand if you pet it. It’s not a good idea to pet wild snakes anyway.

The rhino viper’s scientific name is Bitis nasicornis. At first I thought it was pronounced like “bite us,” which I thought was hilarious, and I was disappointed to find that it’s pronounced “bit-us,” although that’s actually funny too. Actually it’s pronounced “bit-is.” It’s spelled B-I-T-I-S. Nasicornis means nose horn, and it definitely has horns on its nose. It has a pair of horns, in fact, side by side, and they stick up and slightly forward. Some rhino vipers even have three nose horns. They’re not true horns, though. Instead they’re made of modified scales. They’re bendy like scales too.

The rhino viper mostly eats rodents but will also eat frogs, birds, and other small animals if it can catch them. It’s an ambush hunter, meaning it hides among fallen leaves and waits for an animal to come too close. Most of the time it moves slowly, but when it strikes, it does so very quickly, in less than a quarter of a second. It has relatively mild venom, although some other Bitis species have venom that’s deadly to humans.

The rhino viper spends most of its time on the ground, but it can climb trees if it wants to. The end of its blunt tail is even partially prehensile, meaning it can curl around branches to help it hang on. This is the closest thing to a hand that snakes have. It can also swim well.

Sometimes the rhino viper is called the butterfly viper because of its colorful markings, and to stop people from confusing it with another closely related snake called Bitis rhinoceros. Rhinoceros also means nose-horn, by the way. B. rhinoceros is also called the West African Gaboon viper because it lives in West Africa. It looks similar to the other rhino viper with a similar pattern but in more neutral tones of brown and tan. It’s sort of a more sophisticated-looking rhino viper. It also has a pair of nose horns but they’re smaller and generally point up and slightly back.

All snakes in the genus Bitis have a threat display that has earned them the name puff adder, although that’s also the name of a specific species, Bitis arietans, that’s extremely venomous. Some people call the various species of hognose snake found in North America puff adders too because of its behavior when it feels threatened. The hognose snake flattens its neck and raises its head so that it looks like a cobra, all the while hissing in a way that sounds like it’s puffing air in and out. Snakes in the genus Bitis have a similarly impressive display. It appears to inflate and deflate as it hisses loudly, as though you’re being warned away by a bicycle tire innertube with keeled scales and nose horns. This is what it sounds like when a puff adder puffs and hisses:

[snake hissing sounds]

Vipers of all kinds are members of the family Viperidae, which includes a whole lot of venomous snakes from many parts of the world. Vipers have fangs that are so long, they’re actually hinged so they can fit in the mouth. Each fang is attached to a small bone that can rotate forward and back to extend and refold the fangs. Most of the time the viper’s fangs are folded down along the sides of the mouth, protected by a sheath of skin. When it’s ready to bite, either in defense or to kill prey, the viper extends its fangs, but because the fangs are delicate and easily broken, the snake waits to extend its fangs until the last possible moment.

The fangs are also hollow and are connected to venom glands located behind the eyes. That’s why so many vipers have triangular heads, because the venom glands take up extra space at the back of the head. The venom glands are equipped with tiny muscles that the snake contracts to send venom flowing through the fangs and into the bite wound, and it can control how much venom it injects, if any.

Vipers in the genus Bitis have especially long fangs with powerful bites, so that many animals die from the bite itself and not the venom. The reason that snakes inject venom into small prey that it could easily kill and swallow without venom is that the venom begins the digestion process. Most snakes don’t actually have very efficient digestive systems, so by having venom that not only kills its prey but starts digesting it before the snake even swallows it, vipers can extract more nutrients from their food.

The rhino viper and the other rhino viper aren’t the only snakes with nose horns. The rhinoceros snake isn’t a viper but it does have a nose horn—in this case just one nose horn, which grows from the tip of the nose and points straight forward. It’s also called the rhinoceros ratsnake or the Vietnamese longnose snake. It lives in rainforests in northern Vietnam and southern China and spends almost all of its time in trees. Adults are a lovely pale green or blue-green. It can grow over five feet long, or 1.6 m, and is a slender, active snake that mostly eats rodents and other small animals.

Another snake with a nose horn is the nose-horned viper. This one lives in parts of southern Europe and the Middle East, and it’s also called the sand viper. Since lots of vipers live in sandy areas but not all vipers have nose horns, I don’t know how you could possibly look at this snake and decide to call it a sand viper and not a nose-horned viper. Also, it doesn’t live in the sand. It likes rocky areas and can sometimes be found in old stone walls where it has lots of crevices to hide in. It eats small animals, including rodents, lizards and other snakes, large insects like centipedes, and the occasional bird.

The nose-horned viper can grow over three feet long, or about a meter. Individuals can be gray-brown, reddish-brown, coppery-red, dark red, or pale brown, and it has a darker zigzag pattern. Like most vipers it’s a chonky, fairly slow-moving snake. Its nose horn points upward in some subspecies, forward in others.

That brings us to the big question: what are these nose horns used for? Why do these snakes have nose horns at all?

The answer is: we don’t know. They’re soft and bendy, made of scales, so they can’t be used as weapons, not that a four-foot-long snake with massive fangs and deadly venom needs to poke at predators with a little nose horn. They’re probably just for display, but only the snake knows for sure.

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

Thanks for listening!

Episode 241: Weird and Wonderful Squirrels

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Our pre-launch Kickstarter page! You can see what the book cover will look like!

Thanks to Liesbet and Enzo for their suggestions this week! Let’s learn about squirrels!

Further reading:

Project Squirrel

Interspecies Breeding Is Responsible for Some Squirrels’ Black Coloring

The Indian giant squirrel, without filter (left) and with filter (right):

Some variable squirrels (see lots more at iNaturalist):

The Eastern gray squirrel:

The Eurasian red squirrel:

The fox squirrel:

White Eastern gray squirrels (photos taken from the White and Albino Squirrel Research Initiative):

A white variable squirrel spotted in Thailand (picture found here):

The African pygmy squirrel:

The least pygmy squirrel of Asia:

Show transcript:

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

It’s finally the squirrel episode! Both Liesbet and Enzo have suggested squirrels as a topic, and Enzo specifically asked about white squirrels, hybrid squirrels, and squirrels in danger. We’re going to cover all those, and also a few squirrel mysteries!

First, though, a quick note to say that the Kickstarter campaign for the Strange Animals Podcast book is definitely going to happen NEXT MONTH! It’ll go live in early October 2021. Don’t worry, I’ll let you know when so you can go pre-order a copy of the book if you want, and in fact I think I’ll do a bonus episode the first day of the Kickstarter. If you want to get an email to remind you when the campaign launches, there’s a link in the show notes to the pre-launch page where you can request an email notification on launch. You can also see what the book cover will look like! Now, on to the squirrels.

The animal we generally just call a squirrel is specifically a tree squirrel, as opposed to ground squirrels. Tree squirrels are arboreal, which means they live in trees, although they spend plenty of time on the ground too. Squirrels mostly eat nuts and seeds, including acorns and the seeds inside pine cones, but will also eat berries, flowers and buds, tree bark and sap, fungus, and sometimes insects, bird eggs, and even baby birds. Squirrels are rodents and are active in the daytime.

Squirrels can be helpful to trees even though they eat tree nuts, because most species bury nuts to dig up and eat later. The squirrel doesn’t always remember where it hid all its nuts, and in spring the buried nuts sprout and grow into new trees. Some species also hide nuts in caches, often in holes in trees.

A squirrel sleeps in a nest made of dead leaves and sticks it builds in the branches of a tree. The nest is called a drey and it’s lined on the inside with moss, grass, and other soft, warm material. A mother squirrel will line the nest with some of her fur right before her babies are born, so the nest is especially soft and warm. Some species also nest in old woodpecker holes. In winter when it’s cold, several squirrels may share the same drey to stay warm, but squirrels are usually solitary. They don’t hibernate, but like most of us, they sleep more in winter and are less active.

Most people know what a squirrel looks like, because it’s such a common animal throughout most of the world. Some squirrel species get used to humans and often live in people’s yards and in city parks. A tree squirrel has a long, fluffy tail, a long, slender body, relatively short legs, small ears, and large eyes. It’s usually gray or brown and sometimes has spots or stripes.

Some tree squirrels look different from the squirrels you may be used to, depending on where you live. Squirrels of the genus Ratufa are called giant squirrels and they’re the size of domestic cats. They live in parts of Asia, especially southeast Asia. The Indian giant squirrel lives in India, and not only is it especially big, up to 20 inches long, or 50 cm, not counting its long tail, it’s brightly colored. Different individuals and subspecies can have different shades of fur, although the belly and front legs are usually cream-colored. The rest of the body can be tan, dark brown, black, cream-colored, rusty-red, or even a dark maroon color. You may have seen pictures online of brightly colored giant squirrels, and while those are real pictures of real animals, the photographer used a filter that enhances the colors to make them look even brighter than they really are.

The Indian giant squirrel and its close relations eat fruit, nuts, flowers, and other plant material, and hardly ever come down from the tall trees where they live.

Another colorful squirrel is the variable squirrel, which also lives in southeast Asia. It’s on the small side for a tree squirrel, less than 9 inches long at most, or 22 cm, not counting the tail. There are over a dozen subspecies that vary in color and pattern, and some researchers think there may be enough differences that it’s actually more than one species of closely related squirrel. It’s a member of a genus called “beautiful squirrels,” because so many species in the genus have pretty markings. Some variable squirrels are white underneath and red-brown above, with little pointed ears outlined in white, and a reddish tail. Some are glossy black with red markings. Others can be gray, black, orangey-red, reddish-brown, brown, or white with various patterns and markings. It’s so pretty that it’s been introduced in places like Japan, Singapore, Italy, and the Philippines, where it can be an invasive species.

The eastern gray squirrel of eastern North America has also been introduced to other areas where it’s become an invasive species. It was introduced to the UK in 1876 and because it’s a large, aggressive species, the native Eurasian red squirrel has been driven almost to extinction in Britain. It’s still doing fine in the rest of its range, though. Habitat loss is also a factor in the red squirrel’s declining numbers, but the gray squirrel certainly isn’t helping.

The gray squirrel also carries a disease called the squirrel parapoxvirus that causes squirrelpox. Don’t worry, only squirrels can catch it. The gray squirrel is mostly immune to the disease, but the red squirrel isn’t. If an infected gray squirrel is bitten by a mosquito that then bites a red squirrel, the red squirrel can catch squirrelpox from the mosquito bite.

The red squirrel is a reddish-brown in color with tufts on its ears, and in winter it grows a thick undercoat to keep it warm. It also generally looks more gray in winter. Some populations of red squirrel in parts of Europe are black, or nearly black, although it still has a white belly. The red squirrel only grows up to about 9 inches long, or 23 cm, much smaller than the eastern gray squirrel, which can grow up to 12 inches long, or 30 cm. Those lengths don’t include the tail. The red squirrel generally prefers fir trees while the gray squirrel prefers deciduous trees, especially oaks, but the gray squirrel will steal food from the red squirrel no matter what kind of food it is.

In its native range in eastern North America, the eastern gray squirrel often lives alongside other species of squirrel. In 1997 an evolutionary behavioral ecologist named Joel Brown noticed that there are two species of squirrel that live in Chicago, Illinois, a large city in the middle of the gray squirrel’s range. The gray squirrel shares the city with the fox squirrel, which is about the same size and looks very similar to the gray squirrel but is more of a rusty-red color. Dr. Brown noticed that the gray squirrel mostly lives in wealthy neighborhoods while the fox squirrel mostly lives in neighborhoods where people don’t have as much money, and he wanted to figure out why.

Dr. Brown started Project Squirrel to study the mystery. The program teaches people how to tell the difference between the two species so they can report what kind of squirrels they see and where they see them. Right away he started noticing patterns. Fox squirrels live in areas where there are more predators, including feral and free-roaming dogs and cats, urban foxes and coyotes, and hawks. Gray squirrels prefer areas where there aren’t as many predators. Dr. Brown thinks it’s because the fox squirrels are bolder and on average a little larger than gray squirrels, which tend to be more shy. He even noticed a change in his own neighborhood when gray squirrels started becoming more numerous, a shift that happened right after a local leash law went into effect, meaning that fewer pets were running loose.

Project Squirrel has since expanded. There’s an app and everything if you want to take part as a citizen scientist and help solve squirrel mysteries.

Another small squirrel mystery is white squirrels. In August of 2021, just last month as this episode goes live, we had a Q&A episode where we talked about the black squirrels Connor was seeing in Michigan. Those black squirrels turned out to be melanistic eastern gray squirrels. Are white squirrels albino animals or is there something else going on?

Albinism is due to a genetic anomaly that causes an individual to lack pigment. That means its fur or hair is pure white and its skin looks pink because the lack of pigment means its blood shows through and makes it look pink. Its eyes will look red or pink for the same reason, although in some animals the eyes are pale blue instead. Humans with albinism have pale blue eyes.

But most white squirrels have dark eyes and may appear pale brown or gray instead of pure white. Instead of albinism, these squirrels are leucistic. Leucism is related to albinism but instead of a lack of pigment, a leucistic animal has reduced pigment. Sometimes the reduced pigment happens all over the body, sometimes in patches. A leucistic animal often has ordinary colored eyes and skin but pale or white fur. In some domestic species of animal, leucism is bred for or happens frequently in a population, like piebald horses and cows with white spots. It’s a common enough condition that I’ve actually seen leucistic birds while birdwatching. Humans can sometimes show a type of leucism called vitiligo that usually develops in adults, where patches of skin lose their pigment over time. It’s most noticeable on people with dark skin but it also happens to people with light skin. You can’t catch vitiligo from someone else; it’s just a genetic anomaly. Unfortunately, sometimes people who develop the condition get treated badly by others, because people are often afraid of things they don’t understand. Now you know what it is and you can share that knowledge when you need to.

In squirrels, individuals with white fur are usually in more danger from predators. Everything likes to eat squirrels, which is why most squirrel species are gray or reddish-brown as camouflage against tree trunks and branches. A white squirrel shows up like a flashing sign saying, “Snacktime!” As a result, squirrels with white fur are rare to start with and usually don’t live long enough to pass their genes along to the next generation—but in some places, they’re much more common.

In many towns in the United States and Canada, white squirrels are not just common, most squirrels are white. Some towns have white squirrel festivals as a way to promote local pride and bring tourists to the area. Why do some places have white squirrels while most don’t, and why are all the white squirrel populations in North America?

It’s all back to the eastern gray squirrel again. Most squirrel species don’t have a gene that can cause leucism, but the eastern gray squirrel does. Other squirrel species can be albinistic since that’s a genetic anomaly that can happen in any animal, but it’s the eastern gray squirrel that shows leucism most commonly. The closely related fox squirrel also sometimes exhibits leucism.

Some towns have high populations of white squirrels because people think they’re neat. If the white squirrels are in a protected area, like a city park or a college campus, there are fewer predators to start with. People who like the squirrels will leave food out for them and make sure no one hurts them, and as a result the squirrels survive to have babies. Since leucism is a genetic condition, the babies of white squirrels are more likely to be white too.

Remember the variable squirrel we talked about earlier in the episode? Some of them exhibit leucism too, usually a pale brown-white all over with dark eyes.

One thing I learned about black squirrels after last month’s Q&A episode is that some black squirrels are hybrids of eastern gray and fox squirrels. The two species are closely related and often live in the same areas, so it’s not surprising that they sometimes interbreed. Hybrid babies may inherit a genetic variant found in fox squirrels that gives them darker fur. Some researchers think that all gray squirrels with black fur may have inherited the gene for black fur color from fox squirrels in their ancestry.

For the most part, though, tree squirrels don’t hybridize very often, probably because in most places, only one species predominates in any given area. Grey squirrels and Eurasian red squirrels belong to different genera and subfamilies, so aren’t very closely related although their habitats sometimes overlap.

Enzo specifically asked about squirrels in danger, and I’m happy to report that most squirrel species are actually doing just fine. Squirrels are adaptable and can learn to live around humans. As long as they have trees to live in and enough food to support a population, they’re okay. The main danger most squirrels face is habitat loss, especially logging and clear-cutting of forests to build houses or businesses.

A subspecies of fox squirrel called the Delmarva fox squirrel was put on the endangered species list in 1967. It’s native to areas of northeastern North America. It’s about the size of the eastern gray squirrel, which it resembles since it’s gray with a white belly, although it’s usually a more silvery gray in color. By 1967 its population had declined by 90% from habitat loss and overhunting. A conservation plan put in place in 1979 focused on protecting the squirrel’s remaining habitat, restoring its habitat wherever possible, and monitoring the population carefully. The program was such a success that in 2015, the Delmarva fox squirrel was removed from the endangered species list. It’s yet another reminder that protecting an animal’s habitat is just as important as protecting the animal itself. The Delmarva fox squirrel now only lives on the eastern coasts of Maryland and Virginia, a much smaller range than before, so continued conservation efforts are in place to keep it safe and healthy.

Let’s finish with the smallest tree squirrel known, the African pygmy squirrel. It lives in tropical rainforests in parts of western and central Africa. It only grows 5.5 inches long, or 14 cm, and that includes its tail! That’s the size of a mouse. We don’t actually know a whole lot about the African pygmy squirrel, but we do know that it’s an omnivore. This is unusual for squirrels, even though most squirrel species will eat the occasional insect or bird egg. The African pygmy squirrel eats insects regularly as well as fruit, bark, and other plant materials. Unlike most squirrels, it doesn’t store food.

The African pygmy squirrel is the same size as the least pygmy squirrel that lives on three islands in southeast Asia. We know even less about the least pygmy squirrel than we do the African pygmy squirrel…or I guess you could say we know the least about the least pygmy squirrel.

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

Thanks for listening!

Episode 239: Mystery Crocodiles

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Thanks to Pranav and Max for their suggestions. Let’s learn about some mystery crocodiles (and crocodile mysteries) this week!

Further reading:

Huge prehistoric croc ‘river boss’ prowled waterways

Extinct “horned” crocodile’s ancestry revealed

New species of crocodile discovered in museum collections

Rediscovery of “Lost” Caiman Leads to New Crocodilian Mystery

The Orange Cave-Dwelling Crocodiles

The horned crocodile’s fossil skull:

A baby Apaporis River caiman, looking fierce but cute (picture from link above):

An orange crocodile (later released, picture from link above):

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. We’ve got a crocodile episode this week you can really sink your teeth into. Thanks to Pranav and Max for their suggestions! (Yes, I do have a cold but hopefully I don’t sound too bad. I got a covid test today to make sure it’s just a cold, and it’s just a cold.)

We talked about crododilians in episode 85, so if you want to learn more about the saltwater crocodile or how to tell the American crocodile from the American alligator and so forth, that’s the episode to listen to. This episode is going to talk about mystery crocodiles!

The partial skull of a massive extinct crocodilian discovered in Queensland, Australia over a century ago was finally described in June of 2021. All we have is the partial skull from an animal that lived between 2 and 5 million years ago, but researchers can estimate the size of the whole animal by comparing the dimensions of its skull with its closest living relation. That happens to be an animal called the false gharial that lives on a few islands in South Asia, including Java and Sumatra. It’s the only living member of the subfamily Tomistominae, which used to be common worldwide. The false gharial can grow as long as 16 feet, or 5 meters, but its extinct Australian cousin was much bigger. The new species, Gunggamarandu maunala, may have grown up to 23 feet long, or 7 meters.

A smaller extinct crocodile, called the horned crocodile, lived in Madagascar until only about 1,400 years ago. It grew a little over 16 feet long, or 5 meters. It had two projections at the back of its head that look like horns, although they weren’t actually horns and probably weren’t all that big or noticeable when the crocodile was alive.

Like Gunggamarandu, the horned crocodile’s fossils were discovered almost 150 years ago but only definitively described in 2021. In this case, though, the delay was because no one could decide where the horned crocodile belonged in the crocodilian family tree. The Nile crocodile lives on Madagascar now, and some researchers assumed that the horned crocodile was either a close relation of the Nile croc or its ancestor. Since new evidence points to the Nile crocodile being a fairly recent arrival to the island, that’s not likely, so researchers analyzed the fossil remains and reclassified the horned croc as a member of the dwarf crocodiles in 2007. Finally, though, a research team analyzed the horned croc’s DNA and determined that it belongs in its own genus and is most closely related to the ancestral species of all living crocodiles. This suggests that crocodiles evolved in Africa and spread throughout the world from there.

Researchers aren’t sure what caused the horned croc to go extinct, but it may have been a combination of factors, including a drying climate on Madagascar, the arrival of humans, and the arrival of the Nile crocodile.

Speaking of the Nile crocodile and DNA, a 2011 genetic study of the Nile crocodile resulted in a surprising discovery. The study tested not just DNA samples gathered from 123 living Nile crocodiles but from 57 crocodiles mummified in ancient Egypt. The goal was to see if there were differences between modern crocodiles and ones that lived several thousand years ago, and to determine whether maybe there was a subspecies of Nile crocodile that hadn’t been recognized by science. Instead, they discovered that what was previously known as the Nile crocodile is actually two completely different species!

The Nile croc lives in Africa and is a large, aggressive animal that can grow just over 19 feet long, or almost 6 meters. The West African croc also lives in Africa and is a smaller, less aggressive animal that can grow up to 13 feet long, or 4 meters. Since crocodiles of all species show a lot of variation in size and appearance, no one realized until 2011 that there were two species living near each other. They’re not even all that closely related.

After the finding was published, zoos across the world tested their crocodiles and discovered that a lot of their Nile crocs are actually West African crocs.

Something similar happened more recently, in 2019, when a team of scientists did a genetic study of the New Guinea crocodile. They gathered DNA from 51 museum specimens from 7 different museums, and compared them to living New Guinea crocodiles. They were hoping to determine if there are actually two species of crocodile living in different parts of New Guinea, which had been suspected for a while. It turns out that yes, there are two separate species! Knowing exactly what kinds of animals live in a particular environment helps conservationists protect them properly.

In 1952 a subspecies of the spectacled caiman was discovered by science, called the Apaporis River caiman. It lives in Colombia, South America and is relatively small as crocs go, maybe 8 feet long at most, or 2.5 meters. After that, though, it wasn’t seen again. This was partly due to how remote and hard to navigate its habitat is, and partly due to a dangerous political situation, with rebel forces occupying the jungle where the crocodiles live. A peace treaty signed in 2016 made it safe for scientists to travel to that area at last, and a Colombian biologist named Sergio Balaguera-Reina visited with various indigenous tribes of the area to ask about the Apaporis caiman and learn everything they knew about it.

At night, he and two local people paddled upriver in a canoe and searched for the caimans—and he found lots of them. He caught as many as he could to take DNA samples before releasing them again. When he got home, he tested the DNA and made a surprising discovery. Even though the Apaporis caimans look very different from another subspecies of spectacled caiman found in other parts of South America, their DNA is quite similar. That means the differences, especially the Apaporis caiman’s much narrower snout, are due to selective pressures in its environment. Balaguera-Reina is working on figuring out the causes of the Apaporis caiman’s physical differences.

The Siamese crocodile was once common throughout South Asia, but habitat loss has had a major impact on the species and for a long time it was thought to be extinct in the wild. It grows up to 13 feet long at most, or 4 meters, and is not very aggressive. It’s kept in captivity in crocodile farms, where it’s bred and killed for its meat and skin, but a lot of those farms have multiple species of closely related crocodiles and they can and do interbreed, meaning that the Siamese crocodiles in the farms are most likely hybrid animals.

In 2001 a team of conservationists traveled to Thailand to search for tigers, and one of their camera traps recorded a Siamese crocodile just walking along the river like it was no big deal. The photograph was especially lucky because it shouldn’t have even happened. The camera traps used actual film, not digital cameras which were still expensive and not very good back then. The rolls of film could capture 36 pictures before the film ran out, but the crocodile appeared on the 37th picture. Film is manufactured in long strips, then cut into pieces and rolled up and put in little canisters for a photographer to put in the camera, and the roll is a little longer than it needs to be because the ends have to be anchored in place. This particular strip of film just happened to be long enough to take 37 pictures instead of 36. If it hadn’t been, the conservationists wouldn’t have known the crocodile was still alive.

A follow-up expedition to look specifically for crocodiles discovered more of them. Since then a captive breeding program was set up, and in 2013 the first hatchlings were released into the wild.

Sometimes when a crocodile is killed, interesting things turn up in its stomach. This is what happened in 2019 when a crocodile farm in Queensland, Australia necropsied one of their saltwater crocs to see what he had died of. The croc was over 15 feet long, or 4.7 meters, and was about 60 years old. When they opened up his stomach, they found a piece of metal and six screws, the kind of metal called an orthopedic plate. It’s used to join two pieces of broken bone or strengthen an injured bone so it won’t break.

Medical devices like this are always etched with a serial number, but the metal was inside the croc’s belly for so long that the serial number was corroded off by stomach acid. This would have taken decades to happen, so the crocodile had to have eaten the metal decades ago, possibly as long as 40 years ago.

The farm contacted the police but so far they haven’t been able to trace what might have happened. The croc wasn’t bred on a farm but had been caught wild. The farm owner sent pictures of the plate to a surgeon, who determined that yes, it was probably from a human, not an animal, and that it looks like a type of plate used in Europe. The farm owner hopes the discovery will one day help solve a missing persons case.

Let’s finish with an interesting discovery in the rainforests of Gabon, a small country on the west coast of central Africa. The Abanda caves in the area are extensive, not very well explored, and full of bats and insects. A man named Olivier Testa, a professional explorer who often leads scientific expeditions into remote areas, heard a rumor about a population of orange [I read this as strange instead of orange and was too lazy to fix it] crocodiles living in the cave system. A lot of people would have just laughed, because everyone knows crocs and other reptiles like hot weather, sunshine, and warm water to hunt in. But when Testa got the opportunity to join an expedition into the cave system in 2010, he remembered the crocodiles.

Guess what they found in the cave. I bet you all guessed correctly. There really were crocodiles in the caves, specifically African dwarf crocodiles, and the biggest ones did look slightly orangey in color. Crocs don’t live in caves, but there they were. The following year the expedition returned, and this time they were there to find out more about the crocs.

A crocodile expert named Matthew Shirley came along, and he figured out why the crocodiles were in the cave. There are an estimated 50,000 bats living in the cave system, so many that the crocodiles could basically just reach up and snap bats off the walls to eat. There are lots of crickets in the cave too, and young crocs eat lots of insects.

As for the orange color of the older crocs, that comes from the water in the cave. Bats have to pee just like every other animal does, and where they roost over the water they pee into the water, naturally. So much bat urine actually has an effect on the water composition, turning it extremely alkaline. This affects the skin color of animals that stay in it for a long time, as the older crocs have.

The cave crocodiles appear to spend the dry season in the caves, eating bats and avoiding humans who hunt crocs. During the rainy season, they emerge from the caves to mate and lay their eggs in rotting vegetation outside.

This is the first population of crocodiles ever found that spends time in caves deliberately. Some researchers speculate that the crocodiles could eventually evolve into a new subspecies of dwarf crocodile that’s especially adapted to the cave system.

You know what we call those? We call them dragons.

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

Thanks for listening!

Episode 237: Geckos and Other Arboreal Reptiles

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Thanks to Riley, Richard, and Aiden and Aiden’s unnamed friend for suggestions this week! We’re going to learn about some geckos and other reptiles that live in trees. Thanks also to Llewelly for a small correction about lions. Also, I mispronounced Strophurus–it should be more like Stroff-YOUR-us but I’m too lazy to fix it.

Further reading:

Cancer Clues Found in Gene behind ‘Lemon Frost’ Gecko Color

A chameleon’s feets:

A rare healthy lemon frost domestic leopard gecko (photo taken from article linked above):

An ordinary leopard gecko:

I don’t remember what kind of gecko this is (golden spiny-tailed?) but I love it:

A crested gecko looking surprised:

The green iguana:

A black mamba. Watch out!

Flying snake alert!

The draco lizard with its “wings” extended (male) and the draco lizard with its “wings” folded (female):

A parachute gecko showing how it works:

Show transcript:

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

This week we’re going to learn about some reptiles, specifically reptiles that live in trees. This is a suggestion from Riley, who wanted to hear about arboreal reptiles in general and the crested gecko in particular. Thanks also to my brother Richard, who suggested the dragon-tailed gecko. An anonymous reviewer also suggested the leopard gecko so we’ll learn about that one too. Specifically, the anonymous reviewer said “me and my friend Aiden suggest either red foxes or leopard geckos.” We actually covered the red fox in episode 138, about city animals, and in episode 106, about domestication, but we’ve only mentioned the leopard gecko briefly way back in episode 20.

Arboreal animals have some traits in common, whether they’re reptiles or mammals or something else. In general, an animal that spends most of its time in trees is small and lightweight, either has long legs or very short legs, may have a long tail to help it balance, and may also have various adaptations to its feet to help it maneuver through branches.

This is the case with the chameleon, which is arboreal and has weird feet. Its feet look more like mittens. The feet are called zygodactylous, which means it has two toes pointing forward and two pointing backwards. A lot of birds have feet like this too. Chameleons have other adaptations for arboreal life, like prehensile tails that can twine around a twig to help it keep its balance. The chameleon really deserves its own episode some day, so let’s move on to learn about some geckos.

The biggest gecko known grows up to two feet long, or 60 cm, but most are much smaller. There are more than 1,800 species known and they’re all really interesting and honestly, adorable. They’re mostly nocturnal and eat small animals like insects. About 60% of all gecko species have toe pads that allow them to walk up walls and windows and even across ceilings.

Like many other lizards, most geckos species can drop their tail if a predator attacks. The tail thrashes around on its own for several minutes, distracting the predator so the gecko can escape. The gecko later regrows a little stumpy tail, but it can’t drop it a second time. Many species of gecko store fat in the tail, so it needs that tail. A genus of gecko called the fish-scaled gecko, which lives on Madagascar and nearby islands, has big scales that come loose easily if an animal tries to bite it or if a scientist tries to capture it. The predator gets a mouthful of scales while the gecko runs off. The scales grow back eventually and can be lost again.

Scientists are always interested in animals that can regenerate parts of the body, to learn how that works. A study published in 2017 identified the type of cells that allow the gecko to regrow the part of its spinal cord that’s lost with its tail. In 2018, the same team published their discovery that geckos renew brain cells. This is amazing, since humans and many other animals are born with all the brain cells they’ll ever have, and if something happens to injure the brain, the damage can’t be repaired. Maybe one day people will be able to heal their brains just like the gecko does.

Most species of gecko don’t have eyelids. Instead, the gecko has a protective scale over its eyeball. To remove dust and other debris from the scale, the gecko licks its eyes.

The leopard gecko grows about 11 inches long, or almost 28 cm, and is one of the species that doesn’t have toe pads. That makes it easier to keep in captivity, since it’s less likely to climb out of its terrarium. It’s a handsome lizard that’s yellowish or orangey in color with black spots, but baby leopard geckos actually have black stripes. It’s native to parts of the Middle East and south Asia where it’s mostly hot and dry, and in the wild it spends its day in a burrow and only comes out at night to hunt.

The leopard gecko has been kept as a pet for so long that some people consider it the first truly domesticated lizard. It’s easy to take care of and is usually comfortable around people. Breeders select for brighter colors than are found in wild geckos, including various color and pattern morphs.

One color variety of domestic leopard gecko is called the lemon frost morph, an especially attractive coloration. It’s a pastel yellow with white underneath and brown or black speckles that form broad bands over the lizard’s back. It’s really pretty and when the trait cropped up unexpectedly around 2015, its owner started breeding for the color. Lemon frost babies were rare and incredibly expensive, with people paying up to $2,000 for a single gecko.

Unfortunately, people soon learned that lemon frost geckos were prone to a type of rare skin cancer that affects the iridophores, which are pigment-producing cells. Up to 80% of all lemon frost morphs develop the cancer. Geneticists have discovered that the color morph is due to a single mutation in a single gene, but that the change in that gene also makes the gecko susceptible to cancer. Scientists are now trying to figure out more about how it works in hopes of learning how to prevent skin cancer in humans.

The dragon-tailed gecko is one name for the golden spiny-tailed gecko, one of twenty species in the genus Strophurus. All Strophurus geckos are from Australia and they all spend most of their lives in trees and shrubs. Unlike other geckos, Strophurus geckos don’t drop their tails when threatened. Instead, they have a unique way of deterring predators. A Strophurus gecko can squirt an incredibly smelly liquid from tiny pores in its tail. If it feels threatened, instead of dropping its tail, it will raise its tail up and wave it back and forth as a warning. It also opens its mouth to reveal a bright yellow or blue lining, which alerts the potential predator that this is not a lizard it wants to mess with. If that doesn’t scare the predator away, it will squirt liquid at its face. The liquid is sticky and smells horrible, and if it gets in an animal’s eyes it can cause eye irritation.

Strophurus geckos grow up to 5 inches long, or 13 cm, and species may look very different from each other. Some are drab and spiny, some are smooth and brighter in color. The dragon-tailed gecko has a broad reddish or golden stripe down the top of its tail.

The crested gecko is native to a collection of remote Pacific islands called New Caledonia. It can grow more than 10 inches long, or 25 cm. It has tiny spines above its eyes that look like eyelashes and more spines in two rows down its back, like a tiny dragon. It can be brown, reddish, orange, yellow, or gray, with various colored spots, which has made it a popular pet. These days all pet crested geckos were bred in captivity, since it’s now protected in the wild.

The crested gecko spends most of its time in trees, and not only does it have adhesive toe pads, it also has tiny claws. Most geckos don’t have claws. It can drop its tail like other geckos, but it doesn’t grow back. This doesn’t seem to bother the gecko, though.

The crested gecko was discovered by science in 1866, but wasn’t seen after that in so long that people thought it was extinct. Then it was rediscovered in 1994, so hurrah for the crested gecko!

Let’s move on from geckos to some other arboreal reptiles. A lot of reptiles live mostly in trees, and not all of them are small. The green iguana, for instance. It’s native to southern Mexico into parts of South America but has been introduced in many other places in the Americas, where it’s often considered an invasive species. In warm weather it lives in trees, although it will climb down to the ground in cool, rainy weather, and it can grow up to six and a half feet long, or 2m.

Although the iguana can be really long, most of its length is tail. It has an incredibly long tail for its size. It’s not that heavy, either, with the biggest green iguana ever weighed only a little more than 20 lbs, or 9.1 kg. Most are much lighter. It has long legs and long toes with claws, which makes it a good climber. It uses its tail to balance. It’s usually a drab olive-green or brown in color, although babies are brighter green with reddish spots and some adults are more orange in color. The tail is patterned with broad stripes. It has spines along its back and down its chin, and males develop a large dewlap that hangs down under the neck.

Although the iguana looks like a small dragon, it eats leaves, flowers, fruit, and other plant material, although it will also sometimes eat a grasshopper or snail and even bird eggs every so often. Many people keep green iguanas as pets, but they can be hard to keep healthy in captivity.

Another big reptile that lives in trees is the black mamba, a snake that lives in parts of Africa. It’s a slender snake that can be black in color, but that’s actually rare. The name black mamba comes from the inside of the snake’s mouth, which is black. When it feels threatened, it will raise its head high and open its mouth as a threat display. It can even flatten its neck to look like a hood like some cobras do. You really don’t want to see this threat display, because the black mamba’s venom is deadly and it’s an aggressive snake. Without treatment and antivenin, someone who is bitten can die within 45 minutes.

The mamba’s body can be gray, gray-green, brown, or brownish-yellow. It can grow nearly 15 feet long, or 4.5 meters, which makes it the second-longest venomous snake in the world, after the king cobra that we talked about in our Q&A episode last week.

The black mamba mostly lives in open forests and savannas, and it’s equally at home on the ground and in trees. It hides in termite mounds or in holes in trees at night, then comes out in the morning to warm up in the sunshine. Then it goes hunting, usually for small animals like rodents but also for larger ones like the rock hyrax. The rock hyrax can grow almost two feet long, or 50 cm, and looks kind of like a big rodent even though it’s not a rodent. It’s actually most closely related to the elephant. The black mamba will sneak up on a hyrax, bite it quickly, and then just wait until it dies to swallow it whole. The mamba also hunts birds and bats, which is why it spends so much time in the trees.

Some reptiles are so well adapted to living in trees that they can glide from tree to tree, like the flying snakes we talked about in episode 56. Flying snakes live in southeast Asia, and of course they can’t really fly. A flying snake has ridged scales on its belly that help it climb trees, and when it wants to move from one tree to another, it can flatten its body by flaring its ribs. This gives it more surface area to catch air, like a long skinny Frisbee. It’s been measured as gliding as far as 100 meters, or 109 yards, which is just a little longer than an American football field.

The largest species of flying snake, the golden tree snake, can grow over four feet long, or 1.3 meters. It’s striped black, gold, and yellow although some may be green and black. It eats small animals it finds in trees, including frogs, birds, bats, and lizards. It’s venomous, but its venom is weak and not dangerous to humans.

Many lizards can glide too, including the draco lizard. The draco lizard is common throughout much of southeast Asia and spends almost its whole life in trees, eating insects like ants and termites. It’s a small, slender lizard that only grows about 8 inches long at most, or 20 cm, and that includes its very long tail. Many gliding animals, like the flying squirrel, have gliding membranes called patagia that stretch from the front legs to the back legs, but the draco lizard is different. It has greatly elongated ribs that it can extend like wings, and the skin between the ribs acts as a patagium. This skin is usually yellow or brown so that the lizard looks like a falling leaf when it’s gliding.

The male draco also has a brightly colored dewlap under its chin that it can extend to attract a mate. When a female is ready to lay her eggs, she climbs down from her tree, finds some soil that’s soft enough for her to stick her head into to make a little hole, and then lays her eggs in the hole and covers them with dirt to hide them.

The draco lizard is beautiful and looks like a tiny dragon, and I want one to live in my garden and every time I go out to water my plants or pull weeds, I want it to fly down and ride around on my shoulder.

To bring us full circle, some geckos can also glide using thin membranes of skin around their body, legs, tail, and toes that act as patagia. They’re called parachute geckos, which is just perfect.

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