Episode 313: The Wolverine and the Kakapo



This week we learn about two interesting animals from opposite parts of the world! Thanks to Felix and Jaxon for suggesting the wolverine and the kakapo.

Further reading:

Study: Wolverines need refrigerators

Kakapo Comeback [this article has some fantastic pictures!]

The wolverine likes cold weather:

So many young kakapos!

The kakapo is a really big bird:

(Photo by Matu Booth)

Show transcript:

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

This week we’re going to cover two animals suggested by listeners who spell their names with an X. I had already picked out these topics from the list and just now noticed both suggesters have X’s in their names. Thanks to Jaxon and Felix for these suggestions!

First, Felix suggested we learn about the wolverine. We’ve talked about it before in episode 62, but there’s a whole lot more to learn about this uncommon animal.

The wolverine is a mustelid, which is a family that includes weasels, ferrets, and other small, long, skinny animals with short legs. But the wolverine is big and broad, although its legs are pretty short. It kind of looks like a small bear and stands about 18 inches tall at the shoulder, or 45 cm. It’s light brown with darker brown or black legs, muzzle, tail, and back, and some have silvery-gray markings too. Its tail is short but fluffy. It lives in cold, mountainous areas, including northern Canada and Alaska, Siberia, and parts of Norway, Sweden, and Finland.

The wolverine is mainly a scavenger of animals that are already dead, but it will also kill and eat pretty much anything it can catch. This includes rabbits, mice, rats, porcupines, geese, and other small or relatively small animals, but it sometimes kills animals a lot bigger than it is, like deer. It will also eat eggs, berries, seeds, and anything else it can find. It’s not a picky eater.

The wolverine nearly went extinct in the 19th century due to overhunting for its fur, which is mostly waterproof and frost-proof. People used it to line winter clothes. The wolverine is also vulnerable to habitat loss and climate change, since it needs deep snow and cold temperatures to survive.

Because the wolverine lives where winters are harsh, when it finds a lot of food, it will sometimes bury it in snow to eat later. It chooses a protected area between boulders or a natural crevice in rocks to put the dead animal, then covers it with deep snow to keep it fresh for longer, just like putting meat in a freezer. Females in particular need this stored food, because they give birth in winter and need lots of food so they can produce milk for their babies.

But if you’ve ever taken food out of the freezer, you know it’s hard as a rock. How does the wolverine eat meat that’s frozen solid? Not only does the wolverine have strong jaws and teeth, it actually has a special tooth in the back of the mouth that points inward, one on each side of the upper jaw. The inward-pointing tooth allows the wolverine to tear off chunks of frozen meat more easily. Other mustelids have this arrangement of teeth too.

A male wolverine roams widely through a large territory, which can sometimes be hundreds of square miles. Pairs often mate for life although they don’t spend a lot of time together, and sometimes a male will have two or three mates. In winter, the female digs a den deep into the snow to have her babies, and while she mostly takes care of them by herself, the father wolverine will visit from time to time and bring everyone food. The babies stay with their mother for up to a year, and sometimes the half-grown wolverines will go traveling with their dad for a while.

The wolverine is sometimes called the nasty cat because it has a strong smell, which it uses to mark its territory. “Nasty cat” is the funniest name for an animal I’ve ever heard.

Next, Jaxon suggested the kakapo, which is a weird and adorable bird. It’s flightless and nocturnal, lives only in New Zealand, and is a type of parrot. A flightless, nocturnal parrot!

The kakapo is really big even for a parrot. It can grow over two feet long, or 64 cm, but since it’s flightless its wings and tail aren’t very big. Its legs are relatively short considering it has to walk everywhere. It has green feathers with speckled markings, blue-gray feet, and discs of feathers around its eyes that make its face look a little like an owl’s face. That’s why it’s sometimes called the owl parrot. Males are almost twice the size of females on average.

The kakapo evolved on New Zealand where it had almost no predators. A few types of eagle hunted it during the day, which is why it evolved to be mostly nocturnal. Its only real predator at night was one type of owl. As a result, the kakapo was one of the most common birds throughout New Zealand when humans arrived.

The Maori discovered New Zealand around 700 years ago. They killed the kakapo to eat and to use its feathers in clothing, and they also brought dogs and the Polynesian rat that also liked to kill and eat the kakapo. Then a few hundred years ago Europeans arrived, bringing all sorts of invasive animals with them, and they also chopped down forests to create more farmland.

By the end of the 19th century, the kakapo was becoming increasingly rare everywhere. When Resolution Island was declared a nature reserve in 1891, early conservationists brought kakapos and kiwis to the island in an attempt to save them. But stoats and feral cats killed them all. Attempts to establish captive breeding programs weren’t successful either. By 1970, scientists worried that the kakapo was already extinct.

Fortunately, a few of the birds survived in remote areas. By now conservationists understood that they had to provide a safe environment for the birds, and that took a lot of effort. Several islands were chosen as kakapo refuges, and then all the introduced mammals on the islands had to be eradicated or relocated. This included animals like deer that ate the same plants that the kakapo relied on, as well as predators. Then native plants and trees had to be transplanted to the islands since they’d been mostly killed off by deer and other introduced animals.

Then, finally, all the kakapos scientists could find were relocated to the islands. There weren’t very many, and most of them were males. 65 birds were introduced to four islands and monitored carefully, both to make sure they settled in well and to make sure no predators found their way to the islands.

Kakapo females only lay eggs when they have plenty of high-protein food, especially the fruit of the rimu tree that only ripens every four or five years, so the females were given extra food to encourage them to breed more often. The extra food helped, but it turns out that when the females were allowed to eat as much as they wanted, most of the eggs they laid hatched male chicks. That was the opposite of what the kakapo needed, so conservationists experimented with the amounts of extra food they gave the birds until finally the eggs were hatching equal numbers of females and males.

Many parrot species mate for life and both parents help take care of the eggs and babies, but the kakapo handles things differently. Males gather on hilltops during breeding season and each male digs out a shallow bowl well apart from other males, sometimes several bowls connected with little trails. If a male gets too close to another male, they’ll fight. Each male stands in his bowl and makes a booming call by inflating a special sac in his throat. The bowl helps amplify the sound and often the male will construct his bowl near a surface that reflects sound, like rock. His calls can be heard three miles away in good conditions, or 5 km, and the sound attracts females.

This system of males competing in one area to attract females is called lekking, spelled L-E-K. We’ve actually talked about lekking before but I don’t remember if I specifically mentioned the term. The area where the males gather is called a lekking ground or an arena or sometimes just a lek. The females walk around inspecting each male, who booms and struts to show how strong and fit he is. If a female is especially interested in one male, she’ll approach him and he starts his courtship dance. This sounds fancy but for the kakapo, it basically means he turns his tail with his wings spread, then walks backwards towards the female. Weird dance, but the female kakapo thinks it’s cool.

After a female chooses a male, they mate and then the female leaves him and walks home. She builds a nest in a hollow tree or in a hidden crevice among roots or rocks, and lays one to four eggs. She takes care of the eggs and the babies by herself, and may continue to feed the babies until they’re around six months old.

The kakapo eats nuts, seeds, fruit, leaves, and other plant material. Its legs are short but strong, and it will jog for long distances to find food. It can also climb really well, right up into the very tops of trees. It uses its strong legs and its large curved bill to climb. Then, to get down from the treetop more efficiently, the kakapo will spread its wings and parachute down, although its wings aren’t big enough or strong enough for it to actually fly. A big heavy male sort of falls in a controlled plummet while a small female will land more gracefully.

While the kakapo is doing a lot better now than it has in decades, it’s still critically endangered. The current population is 249 individuals according to New Zealand’s Department of Conservation. Scientists and volunteers help monitor the birds, especially newly hatched chicks. If a mother bird is having trouble finding enough food for all her babies, or if any of the babies appear sick or injured, a team of conservationists will decide if they need to help out. They sometimes move a chick from a nest where the mother bird has a lot of other babies to one where there are only one or two babies. Some chicks are raised in nurseries if necessary and reintroduced to the wild when they’re old enough.

The kakapo can live for a long time. This isn’t unusual for parrots, which can live as long as a human, but the kakapo is especially long-lived. There are reports of individuals who have reached 120 years old. This means that potentially, only six kakapo generations ago, the first East Polynesian sailors, ancestors of the modern Maori, became the first humans ever to set foot on the shores of New Zealand. And there were some weird parrots there.

This is what the male kakapo sounds like when it’s booming:

[booming call]

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. 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 312: Little Bouncy Animals



Thanks to Zachary and Oran for this week’s topic, some little animals that bounce around like tiny kangaroos!

Further reading:

Evolution of Kangaroo-Like Jerboas Sheds Light on Limb Development

Supposedly extinct kangaroo rat resurfaces after 30 years

High-Speed Videos Show Kangaroo Rats Using Ninja-Style Kicks to Escape Snakes

Williams’s jerboa [picture by Mohammad Amin Ghaffari – https://www.inaturalist.org/photos/177950563, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=115769436]:

A drawing of a jerboa skeleton. LEGS FOR DAYS:

The San Quintin kangaroo rat lives! [photo from article linked above]

Show transcript:

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

This week we’re going to learn about two cute little animals suggested by Zachary and Oran! Both of these animals are rodents but although they look remarkably alike in some unusual ways, they’re not actually all that closely related.

First, Zachary suggested the jerboa. We talked about the pygmy jerboa in episode 136, but we haven’t talked about jerboas in general. It’s a small rodent that’s native to the deserts of Asia, north Africa, and the Middle East. It’s usually brown or tan with some darker shading on the back and tail. It looks sort of like a gerbil with long ears, long hind legs, and a tuft at the end of the tail. Its front legs are short and it has an adorable whiskery nose.

The reason the jerboa’s hind legs are so long while its front legs are really short is that it jumps around on its hind legs like a kangaroo. Not only can it jump really fast, up to 15 mph, or 24 km/h, it can change directions incredibly fast too. This helps it evade predators, because most animals are fastest when running in a straight line. The jerboa bounces in all sorts of directions, hopping or just running on its long hind legs, with its long tail held out for balance. It can also run on all fours with its short front legs helping it maneuver, but for the most part it’s a bipedal animal. It has tufts of stiff hairs under its toes that help it run through loose sand.

The jerboa eats plants, although sometimes if it finds a nice juicy insect it will eat it too. Mostly it just eats leaves, bulbs, roots, and some seeds. It gets all of the moisture it needs from its diet, which is good because it lives in the desert where there’s not much water available.

Some species of jerboa mainly eat insects and spiders, and some have short ears instead of long ears. This is the case for the thick-tailed pygmy jerboa that lives in parts of China, Mongolia, and Russia. Its head and body only measures about two inches long, or almost 5 cm, but its tail is twice that length. The reason it’s called a thick-tailed jerboa is because it stores fat at the base of its tail, which makes the tail look thick compared to many rodent tails.

The jerboa is mostly active at dawn and dusk, although some species are fully nocturnal. It spends the day in a burrow it digs in sand or dirt. A jerboa will usually have more than one burrow in its territory, with the entrances usually hidden under a bush or some other plant. Different burrows have different purposes. Some have numerous entrances and lots of side tunnels but are relatively shallow, which is useful if the jerboa lives in an area with a rainy season. A shallow burrow won’t flood if it rains a lot. Some burrows are temporary, which the jerboa may dig if it’s out and about during the day looking for food. A mother jerboa will dig a burrow with a roomy nesting chamber to raise her babies, and a jerboa’s winter burrow has a nesting chamber that’s deep underground to help it stay warm. Some species of jerboa construct unusual burrows, like the lesser Egyptian jerboa that has spiral-shaped burrows with storage chambers. Most jerboas are solitary animals, although sometimes a group will hibernate together in winter to help everyone stay warmer.

Scientists have been studying the jerboa to learn how different animals have evolved radically different leg lengths. The jerboa’s incredibly long hind legs are very different from its very short front legs, but it evolved from animals that had four short legs. But jerboas are born with four short legs, and as the babies grow up their hind legs grow longer and longer.

The jerboa is an incredibly efficient runner. Some species can jump as far as six feet in a single bound, or 1.8 meters, and up to three feet, or 90 cm, straight up.

The jerboa isn’t the only rodent that hops on its hind legs like a kangaroo. The kangaroo rat does too, and it’s Oran’s suggestion. Oran pointed out that a long time ago, I think in the humans episode, I said that humans are the only fully bipedal mammal, meaning we only ever walk on our hind legs. (Crawling when you’re a baby or trying to find something under the couch don’t count.) I was wrong about that for sure, because the kangaroo rat, the jerboa, and a few other mammals are also bipedal.

The kangaroo rat is native to parts of western North America. It looks a lot like a jerboa, with long hind legs and a long tail, although its ears are smaller. But the kangaroo rat and the jerboa aren’t closely related, although both are rodents. Their similarities are due to convergent evolution, since both animals live in very similar environments with the same selective pressures.

The largest species of kangaroo rat, the giant kangaroo rat, grows around 6 inches long, or 15 cm, with a tail about 8 inches long, or 20 cm. It can jump even longer than the jerboa although it doesn’t move as fast on average.

Like the jerboa, the kangaroo rat can change directions quickly, and it’s also mostly nocturnal and spends the day in a burrow. Some species spend almost all the time in burrows, only emerging for about an hour a night to gather seeds. Since owls like to eat kangaroo rats, you can’t blame them for wanting to stay underground as much as possible.

Snakes also like to eat kangaroo rats, especially the sidewinder rattlesnake. It’s a fast predator with venom that can easily kill a little kangaroo rat, but the kangaroo rat isn’t helpless. A study published in 2019 filmed interactions in the wild between the desert kangaroo rat and the sidewinder, using high-speed cameras. They had to use high-speed cameras because the snakes can go from completely unmoving to a strike in under 100 milliseconds. That’s less time than it takes you to blink. But the kangaroo rat can react in even less time, as little as 38 milliseconds after the snake starts to move. A lot of time the kangaroo rat will completely leap out of range of the snake, but if it can’t manage that, it will kick the snake with its long hind legs, which are strong enough to knock the snake away. Little fuzzy ninjas.

Unlike the jerboa, the kangaroo rat mostly eats seeds. The jerboa’s teeth aren’t very strong so it can’t bite through hard seeds, but the kangaroo rat’s teeth are just fine with seeds. The kangaroo rat also has cheek pouches, and it will carry lots of seeds home to its burrow. It keeps extra seeds in special burrow chambers called larders.

The kangaroo rat sometimes lives in colonies that can number in the hundreds, but it’s still a mostly solitary animal. It has its own burrow that’s separate from the burrows of other members of its colony, and it doesn’t share food or interact very much with its neighbors. It will communicate with other kangaroo rats by drumming its hind feet on the ground, including warning its neighbors to stay away and alerting them to predators in the area.

The kangaroo rat is vulnerable to habitat loss, since it mostly lives in desert grassland and humans tend to view that kind of land as useless and in need of development. An example of this is the San Quintin kangaroo rat, which is only found in western Baja California in Mexico. Only two large colonies were known when it was discovered by science in 1925, although it used to be much more widespread. But in the decades since 1925, the land was developed for agriculture until by 1986 the two colonies were completely wiped out. Scientists worried the species had gone extinct. Then, in 2017, a colony was discovered in a nature preserve and everyone breathed a sigh of relief. Other colonies have been discovered on farmland that has been abandoned due to drought. Still, the San Quintin kangaroo rat is critically endangered.

The kangaroo rat is actually helpful for the environment. Because it stores seeds underground, and sometimes forgets where it put them, it helps native plants spread. Its burrows help increase soil fertility and the spread of water through the soil. This is similar to the jerboa, which also eats enough insects to help reduce the number of agricultural pests in some areas.

There are also two species of kangaroo mouse, which are closely related to kangaroo rats. They mostly live in the state of Nevada in North America. There are also jumping mice that look like ordinary mice but with long hind legs. It also has cheek pouches. While some jumping mice live in western North America, some live in northeastern North America and Canada and are adapted to cold weather and long winters. One species of jumping mouse lives in the mountains in parts of China. There’s also a larger jumping rodent called the springhare that lives in parts of Africa, and which is about the size of a squirrel or a small rabbit. Like all these other rodents, it’s bipedal and hops on its hind legs like a little kangaroo, using its long tail for balance and to prop itself up when it’s standing. It mostly eats plants but will sometimes eat insects, and it spends most of the day in burrows. There’s also a hopping mouse native to Australia, which is a rodent with long hind legs and a long tail and long ears. It’s not closely related to the jerboa or the kangaroo rat, but it looks a lot like both because of convergent evolution. It mostly eats seeds.

All these animals are rodents, but Australia also has another animal called the kultarr that looks a lot like the kangaroo rat and the jerboa. It’s not a rodent, though. It’s actually a marsupial that’s completely unrelated to rodents although it looks like a rodent. That’s definitely what you call convergent evolution.

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 311: The Mystery Deep-Sea Spider



Thanks to Llewelly for this suggestion, and thanks to Dr. Thomas A. Hegna for providing me with the two papers I reference in this episode!

Images are taken from the papers.

The mystery “spider”:

Long-legged isopods:

Show transcript:

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

My carefully planned out episode schedule has already gotten messed up, but I got excited about this topic and couldn’t wait to share it! It’s a mystery invertebrate from the deep sea that has been solved! Thanks to Llewelly for bringing this to my attention, and thanks to arthropod paleontologist Dr. Thomas A. Hegna for posting this information on Mastodon in the first place, and for providing the relevant papers to me. People are pretty great.

I knew about this topic from the book The Search for the Last Undiscovered Animals by Karl Shuker, but I hadn’t been able to find out more. Until now.

In the late 1980s, a program called DISCOL 1 was launched to study disturbances on the sea floor due to underwater mining. It focused on the deep sea in the South Pacific. One of the things the expedition did was drop underwater cameras with bait tied to them. When an animal came to investigate the bait, the camera took pictures. I have a birdfeeder like this now although I don’t have to drop it anywhere.

In February 1989, the camera descended to about 13,600 feet, or 4,150 meters, in the Peru basin. When it was hauled up a few days later and the pictures retrieved, the scientists saw something they didn’t recognize on 20 of the photos. It looked like a spider.

The scientists were able to get a good idea of the animal’s size because they knew how big the bait was and how big the metal rod was that the bait was tied to. The animal’s body was about 2 and a half inches long, or 6 cm, and about half that width, not counting its long, jointed legs. It had five pairs of appendages, including three pairs of walking legs. The other two pairs of appendages were longer and might be feelers of some kind, with the front pair possibly used to manipulate food. The estimated legspan was almost 8 inches across, or more than 20 cm.

The scientists published a short article about the finding later in 1989 and proposed that the animal be tentatively placed in the phylum Arachnida with spiders and their relations. But this placement is a big deal, because there are no known spider relations that live in deep water. Some spiders have evolved to live in water at least part of the time, but they always have to have access to the air.

For a long time that’s all anyone knew. Most scientists thought the animal was probably a pycnogonid [pik-NA-gunid], an arthropod commonly called a sea spider although it’s not actually an arachnid. We talked about sea spiders in episode 105, so I’ll revisit some of the information from that episode.

Sea spiders live throughout the world’s oceans and there are well over a thousand known species. Most are small and live in shallow water, but a few live in water up to 23,000 feet deep, or 7,000 meters. The biggest species live in the cold waters around Antarctica, with the very largest individual ever found having a legspan of about 27 inches across, or 70 cm.

The sea spider has four pairs of legs, although a few species have five or six pairs of legs instead. Some species have one or two pairs of simple eyes, but other species have no eyes at all. The body is quite small in relation to the legs, which are extremely long, which means the digestive tract is actually partly in the legs, because the body is too small for it. It walks along the bottom of the ocean or may swim by pulsing its long legs like a jellyfish with legs instead of a bell. In species that swim, the legs may be lined with long bristles.

Some species have mouthparts, but most eat using a proboscis that it uses to suck fluids out of its prey. Some species have spines at the tip of the proboscis. It sticks its proboscis into a sponge, worm, jelly, sea anemone, or other invertebrate, injects digestive fluids that liquefy the surrounding tissues, and slurps the fluids up. Sometimes this kills the prey animal, sometimes it doesn’t.

All this does sound a lot like the spider-like animal photographed in 1989. But in 2004 a new paper was published about the animal, where the original scientists teamed with some other experts to re-examine the photographs. Their conclusion is that the mystery animal wasn’t a spider or a sea spider but something else: a munnopsidid isopod.

Isopods are crustaceans that have been around for at least 300 million years. They live all over the world, on land and in both fresh water and in the ocean. The animal sometimes called the woodlouse or pill bug or roly-poly or sow bug are actually isopods. All isopods have segmented exoskeletons, as you may have seen in roly-polies or whatever you call those little guys, and all have two pairs of antennae and seven pairs of jointed legs.

Isopods are very common animals in the ocean and the most common isopods are members of the family Munnopsidae. Most have short legs but some have long legs, including some species in the subfamily Bathyopsurinae.

While Munnopsids are common, there are only four species in two genera in Bathyopsurinae. The biggest isopods live in the deep sea and while these four species are pretty big, up to 2 and a half inches long, or 6 cm, they’re nowhere near the size of the largest isopods known. That would be the giant isopod that can grow up to 20 inches long, or 50 cm, but it’s not closely related to these four species.

As to which species the mystery isopod belongs to, the photographs aren’t close enough or clear enough for a definite identification. It’s possible the mystery isopod belongs to a species unknown to science.

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 310: The Crab-Eating Fox



Thanks to Dean for this week’s suggestion, the crab-eating fox!

Further reading:

Jaguars could prevent a not-so-great American biotic exchange

The crab-eating fox is not actually a fox:

Show transcript:

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

I’m happy to report that I’m feeling healthy and testing negative for covid now. Even my lingering cough has pretty much cleared up! I hope you’re healthy too. Anyway, this week let’s learn about an unusual animal suggested by Dean, the crab-eating fox.

The crab-eating fox lives in parts of South America east of the Andes Mountains. It likes forests and open woodlands, and sometimes lives in savannas too although it prefers areas with a lot of tree cover and rivers. It’s a fairly small animal that rarely weighs more than 18 pounds, or 8 kg, and stands about 16 inches tall at the shoulder, or 40 cm. It has a thick coat that’s mostly gray or brown with reddish ears and paws, black markings on the ears, tail, and legs, and a black stripe down its spine. It also has a bushy tail and a relatively short muzzle.

There are two important questions we need to answer about the crab-eating fox. First, does it actually eat crabs? Second, is it actually a fox?

The crab-eating fox does indeed eat crabs, although it’s an omnivore and will eat pretty much anything it can find. This includes insects, eggs, fruit, carrion, and small animals of various kinds, especially rodents. But during the wet season, when it rains a whole lot and rivers flood and ebb repeatedly, the crab-eating fox eats a whole lot of crabs and other crustaceans.

The crab-eating fox is not, in fact, a fox. It’s definitely related to foxes, since it’s a canid and the family Canidae includes foxes as well as wolves, dogs, coyotes, and all their relations, and it looks like a fox. It’s the only member of its own genus, but it’s grouped together with some other South American canids that look like foxes but are more closely related to wolves. But they’re not all that closely related to either foxes or wolves. Another member of this group is the maned wolf, the one with super long legs, which we talked about most recently in episode 167.

Scientists think that the crab-eating fox’s closest relation is another South American canid called the short-eared dog, which we talked about in episode 195. Unlike the crab-eating fox, the short-eared dog likes heavy forests and lives in the Amazon rainforest. We know so little about it that researchers sometimes refer to it as the ghost dog.

The crab-eating fox is nocturnal and spends most of the daytime sleeping in a den. Sometimes it makes a den by burrowing into thick grass, sometimes it will dig a burrow, but it prefers to find a den made by another animal and move into it if it’s empty. It may have several dens in its territory, which it often shares with its mate. Both parents help take care of the babies, and a female may have two litters a year.

I’m happy to report that the crab-eating fox is not endangered. It’s doing just fine in most places. It’s an adaptable, intelligent animal, which helps it thrive in a changing environment the same way coyotes do in North America. In fact, it fills the same ecological niche in South America that the coyote fills in North America, and this has led to a really weird potential problem.

The crab-eating fox is native to South America, but it has been spreading northward into Central America. Likewise, the coyote is native to North America, but it has been spreading southward into Central America. Neither species likes thick forested areas, but as more rainforests are cleared for agriculture and housing, people have inadvertently made a sort of corridor for both species. Having people around doesn’t bother either the crab-eating fox or the coyote. Coyotes have made it as far south as Panama, almost to South America.

If this continues, with crab-eating foxes migrating north and coyotes migrating south in ever greater numbers, eventually they’ll start to compete with each other. This isn’t good for either of them.

The only thing stopping coyotes from migrating farther south at this point is a thick strip of tropical forest called Darien National Park in Panama, where jaguars live. Unlike coyotes and crab-eating foxes, jaguars are very shy of humans and need a lot of dense forest to live in. This is exactly the kind of place that coyotes and crab-eating foxes like least, not to mention that a jaguar would be more than happy to catch and eat either species of canid. So as long as the forest in the national park remains intact, it acts as a barrier to keep both canid species apart, and that’s good. It’s also good for the jaguars and lots of other animals. Hooray for protected forests!

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 309: The Red Panda



Thanks to Zola for suggesting this week’s topic, the red panda!

Further reading:

Study Reveals Key Differences in Skulls of Red and Giant Panda

A red panda:

A red panda asleep in a tree [photo by By Aconcagua – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2169002]:

Not exactly a real red panda but pretty darn cute (from the Disney/Pixar movie Turning Red):

Show transcript:

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

Happy new year! I’m still getting over covid but feeling much better and have mostly regained my sense of smell and taste. I’m still coughing, though, so apologies that my voice doesn’t sound great (at least, I don’t think it does).

One of my goals for this year is to really clear out the backlog of suggested topics. So many people have sent me such great ideas for episodes, and while I really do try to get to as many of them as possible, some people have been waiting literally years for me to cover their suggestion. So I’m just going to pick one every week until we’re more or less caught up.

We’ll start with someone who’s probably used to being at the end of the line when you have to line up alphabetically. Zola suggested the red panda and I have no idea why we’ve never talked about this amazing animal!

The red panda lives in parts of the Himalaya Mountains in various countries, including China, India, Tibet, Myanmar, and Nepal, where it mostly lives in high elevations where there’s plenty of water and bamboo. When it gets really cold, it can lower its metabolism and enter a torpid state something like hibernation, although only for short amounts of time, and it also wraps itself up in its big fluffy tail to stay warm. It’s mostly nocturnal and spends a lot of time in trees, although it’s perfectly comfortable on the ground too, although it almost always sleeps in a tree.

The red panda is about the size of a dog but with short legs. It’s bigger than a raccoon but resembles one superficially, including a bushy ringed tail and a dark stripe across the eyes that continues down the cheeks. It’s mostly reddish-brown or orangey in color, with white markings on the ears and face and darker red or black belly and legs. Its tail is almost as long as its body, around 19 inches long for a big male, or 48 cm, while its head and body is about 25 inches long, or 63 cm. It has a round head with a short muzzle and big triangular ears.

The red panda has a lot in common with the giant panda, and that has caused a lot of confusion in the past and even today. We talked about the giant panda in episode 42, including its extra toe. It’s not really a toe although it acts like a thumb. The giant panda’s front paws have five toes just like all bears, and also a modified wrist bone that juts out from the base of the paw and helps the panda hold bamboo stalks as it eats the leaves.

The red panda has a false thumb too, also formed from a projecting wrist bone. It’s not as dexterous as the giant panda’s false thumb, but both animals use it to help it hold bamboo. In the red panda’s case, though, the false thumb probably originally evolved to help it climb trees. It also has flexible joints in its legs that allow it to climb more easily, including straight down a tree head-first, and it has semi-retractable claws.

The red panda even lives in some of the same places as the giant panda. Researchers weren’t sure how the two species could live in the same places and eat the same foods without one species out-competing the other. The red panda mostly eats bamboo just as the giant panda does, and both are considered carnivores even though they hardly eat anything but plants, but a study published in 2014 determined that the two animals actually eat different parts of the bamboo plant. The red panda is able to climb up to eat the smaller, more tender leaves and stems while the giant panda has a stronger jaw that allows it to eat larger, tougher leaves and shoots.

But is the red panda closely related to the giant panda? Scientists still aren’t completely sure. The red panda was known to science long before the giant panda was, and was just called the panda. After the giant panda was discovered, scientists thought that it had to be related to the red panda, which they started calling the lesser panda or red panda to differentiate it from the giant panda. The two animals eat the same thing and have some traits in common, so it made sense that they were related. But that was before the giant panda was well understood.

Once scientists figured out that the giant panda is actually a type of weird bear, they reclassified it and determined that the red panda was probably more closely related to procyonids, which includes the raccoon and the coatimundi we talked about a few weeks ago. After genetic studies, currently the red panda is placed in its own family and is probably most closely related to the family Mephitidae, which includes skunks, but is also closely related to procyonids like raccoons and mustelids like weasels and otters. While it is distantly related to the giant panda, its false thumb and other similarities to the giant panda are probably due to convergent evolution.

In the wild red pandas seem to be mostly solitary except during breeding season, which is in winter, although it’s difficult to observe in the wild so we don’t know for sure. In captivity it’s more sociable and will play-fight with its friends. While it mostly eats bamboo, it will also eat flowers, bird eggs, berries, and leaves from other plants.

The female red panda gives birth to three or four cubs in summer, and while they’re born with fur they need their mother’s care for several months before they can start to learn independence. They’re usually old enough to leave their mother at around 7 or 8 months old, at which point they set off to find small territories of their own.

The red panda is endangered by habitat loss, pollution, competition with livestock, and poaching for its fur. This is despite the animal being a protected species everywhere it lives. Fortunately, more and more people in the countries where it lives are helping to protect the red panda’s habitat. In Nepal, for instance, lots of schoolchildren have learned about the red panda and are helping with conservation efforts, including putting up fences to keep livestock out of bamboo forests. Red pandas also do well in captivity and are popular zoo exhibits because one thing I haven’t mentioned is that they’re completely adorable!

The third Saturday in every September is International Red Panda Day to raise awareness and money for conservation efforts. You have approximately 9 and a half months to prepare for International Red Panda Day 2023.

This is what a red panda sounds like:

[red panda 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 308: Rescuing Stranded Whales



Yay, we’re at the end of the year and looking forward to 2023! Boo, I caught covid and I’m still recovering, so here’s a repurposed Patreon episode about whale strandings and how people help the whales!

A minke whale calf being transferred via rescue pontoon to a boat to tow her farther out to sea than the pontoon could manage for such a big whale (photo from this article, which explains that she rejoined her mother and swam away safely):

Pilot whales being rescued after stranding:

Show transcript:

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

It’s the last episode of 2022, and…I’ve got Covid. I’m fully vaccinated and fortunate enough to be a basically healthy person, so my symptoms were mostly quite mild and I’m feeling much better although I’m still quarantining. Because my voice isn’t really at 100% due to coughing, and because I haven’t had the energy to do any research, I decided to run an old Patreon episode this week. I always feel bad for my awesome patrons when I do this, but I really like this episode and it’s several years old now. It’s about mass whale strandings but I focused on how people help whales, so even though it’s a sad topic I hope you find it hopeful and interesting.

With the end of 2022, we also say goodbye to the birthday shout-outs since it was only for 2022. I hope I didn’t miss anyone. Let’s have one final birthday shout-out, though. This one’s for everyone! You’re having a birthday in 2023 so I hope it’s the best birthday you’ll have had so far!

Now, let’s learn about mass whale strandings.

[little intro sound to help hide the fact that the audio changes a whole lot here]

This is a sad phenomenon where whales swim onto shore and get beached, and if they don’t get help they die. A whale breathes air, sure, but it’s evolved to be in the water full-time. As soon as it’s on land, the weight of its own body starts to smother it and it also starts to overheat.

Sometimes just one or two whales strand themselves, sometimes it’s a whole pod. We’re still not completely sure of the causes except that there’s undoubtedly more than one cause. Navy sonar may play a part, disorienting and frightening whales, even deafening them. Water pollution, disturbances of the earth’s geomagnetic field, extreme weather, injuries, disease, the whales fleeing predators or pursuing prey, and all sorts of other issues may be causes or partial causes.

Most whales that strand themselves are toothed whales, which rely on echolocation to navigate. Many researchers think that some coastlines that slope very gently can confuse the whales, who think the seafloor is level when the water is actually getting shallower and shallower. Certain areas with gently sloping beaches have mass strandings of whales and dolphins almost every year.

Some species of whale are more prone to stranding than others, too, especially pilot whales, which are actually dolphins despite their name. The largest mass stranding known was of pilot whales, with over a thousand of them beached in 1918 on Chatham Island in New Zealand. Pilot whales can grow more than 23 feet long, or over 7 meters, and live throughout much of the world’s oceans. They mostly eat squid but will eat fish too, and sometimes dive deeply to find food.

Chatham Island is one of those areas where whales get stranded repeatedly, as are several other islands and bays around New Zealand. The coastal waters are shallow with a number of sandbars, and the whales apparently get disoriented and don’t realize they’re coming up onto the beach instead of just crossing another sandbar. Almost every summer some pilot whales become stranded, sometimes hundreds of them.

One species of whale that almost never gets stranded is the killer whale, or orca. Orcas frequently hunt seals, which flee onto land. Orcas learn how to navigate beaches, and will sometimes beach themselves on purpose while attempting to catch a seal, then wriggle back into the sea. But most whales never approach the shore that closely under ordinary circumstances so they never learn how to avoid getting stranded permanently.

When people find stranded whales, our first impulse is to help them. But whales are big and heavy, so much so that most of the time even a group of people can’t lift them. But humans are smart and social, and we’ve worked out a system to help stranded whales.

First, the whales need to be kept as cool as possible until more help arrives. People pour water over stranded whales to help cool them down, but make sure that their blowholes remain clear of sand and water so they can continue to breathe. Wet bed sheets draped over the whales help too, again making sure to keep the blowholes clear.

Next, as the tide comes in and the water rises around the whales, it’s important to help turn the whales onto their bellies. The whales usually can’t do it themselves, especially if they’ve been stranded for hours and are exhausted and having difficulty breathing. If they aren’t turned upright, they may drown as the water covers their blowholes before it’s deep enough to float the whales.

Sometimes, frustratingly, as soon as a stranded whale is floated out to sea so it can swim away, it will turn around and beach itself again. No one’s sure why. It may be responding to the same confusion or anomaly that caused it to strand itself in the first place, or it may be responding to the distress calls of other whales that are still stranded.

Rescuers have used the sociability of whales to help them too. In one case in New Zealand, in 1984, almost 150 pilot whales became stranded in Tryphena Harbour. As the tide rose, the helpers floated the whales out to sea—but so many of them returned to beach themselves again that when they floated a mother whale and her calf out to sea, the rescuers made sure to keep her in place. She and the baby called to the other whales, which made them come to her instead of return to the beach. 67 of the whales were saved and ultimately swam out to sea.

In 1991, 14 pilot whales stranded near Shipwreck Bay in New Zealand were rescued by truck. The surf was too dangerous to refloat them at the beaching site and something had to be done. 18 whales had already died. Hundreds of volunteers turned out to help, including local businesses who donated the use of trucks and other items. The whales were lifted by log-loader onto three big trucks, their beds lined with hay, and hay bales were used to keep the whales propped up during the ride. People rode with them to douse them with water too. The police escorted the trucks as they drove 90 minutes to the mouth of a river, where the whales were lowered into the water and floated out to sea.

Two of the whales promptly turned around and beached themselves again, but the volunteers had brought Rescue Pontoons designed to refloat beached whales. The two whales were brought back out to sea where they rejoined the rest of the rescued whales, which then swam off together.

The rescue pontoons were designed in 1984 by New Zealander Steve Whitehouse after he saw the damage ropes did to whales as rescuers tried to pull them back out to sea. They’re made up of inflatable cylinders with handles and quick release clips. After the first one was made it was tested by moving a huge concrete pipe filled with sandbags into the ocean and back repeatedly. It was first used to rescue a whale in 1986 when a Southern Bottlenose whale was stranded among rocks that would have kept it from being moved by ordinary means. But Steve and his team traveled to the whale, rolled it onto the pontoon and inflated it, then refloated it into the sea. The whale was saved and the rescue pontoon proved it could do the job it was designed for.

Since then, the rescue pontoon has saved hundreds, probably thousands, of whales and dolphins throughout the world. It’s also been used to rescue stranded manta rays, sunfish, and even grounded boats. So hooray for Steve and his rescue pontoon! Best invention ever.

Humans aren’t the only ones who want to help stranded whales. Sometimes other whales or dolphins help, usually local populations of dolphins who know the area well. In 2008 a New Zealand bottlenose dolphin named Moko, well-known to swimmers, helped a pair of pygmy sperm whales. The pair were a mother and calf, and every time they were refloated they would get disoriented and beach themselves again on a sandbar that blocked their way out of the harbor. Then Moko showed up.

One of the rescuers, Juanita Symes, said, “Moko just came flying through the water and pushed in between us and the whales. She got them to head toward the hill, where the channel is.” Moko escorted the whales all the way out to sea, where they successfully swam away.

[little outro 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 307: Coquí Frogs and Glass Frogs



Thanks to Miranda and Henry for this week’s frog suggestions!

Further reading:

Shattering the Glass Frog Ceiling

The Puerto Rican wetland frog, AKA coquí llanero:

The golden coquí in happier times:

Glass frog from above and below:

A female granulosa glass frog named Millie (in one of the few successful breeding programs of these frogs), looking demure:

Laura’s glass frog, rediscovered after almost 70 years [photos from this article]:

Show transcript:

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

This week we have suggestions from Henry and Miranda, so we’re going to learn about some weird but cute frogs!

First, Miranda listened to episode 270 about the tapir frog and commented about a little frog native to Puerto Rico that sounds very similar. It’s call the coquí frog and it has an adorable beep! It sounds like this:

[frogs beeping]

You can definitely hear why the coquí frog is called that. It sounds like it’s saying “coquí.”

The coquí is a type of tree frog although most species prefer to live on or near the ground. Instead of webbed toes, their toes have discs that act sort of like suction cups that help them stick to leaves. Different species of coquí frogs are different colors, including brown, green, gray, and yellow. Their tummies are usually white or yellow. Most species are quite small, although a few species grow as big as 3 inches long, or about 8 cm.

There are at least 17 species of coquí frog known in Puerto Rico, with more species found in other parts of the Caribbean and in Central and South America. New species are discovered from time to time, including the tiniest species, the Puerto Rican wetland frog. It was only discovered in 2005 and described in 2007. It’s about 15 mm long from nose to butt, or more properly snout to vent, and while males are bright yellow, females are browner. It lays its eggs on the leaves of a plant called the bulltongue arrowhead, and it only lays one to five eggs at a time. Instead of hatching into tadpoles, the eggs hatch into miniature frogs which are ready to hop out and eat lots of ticks, because that’s mainly what this species of coquí eats. And that’s about all we know about this particular species except that it only lives in one small area of Puerto Rico and is critically endangered.

Another species of coquí is the golden coquí, which is almost as small as the Puerto Rican wetland frog. It’s yellow or golden in color, or sometimes a more olive green. Instead of laying eggs that hatch into tadpoles that develop into frogs, the golden coquí skips most of these steps and just gives birth to fully developed teeny baby frogs, three to six of them at a time.

The golden coquí lives in a small, specific habitat, a moist subtropical forest where bromeliad plants grow. Bromeliads are shrubby plants with succulent-type leaves that retain water. Pineapples are a type of bromeliad, although not the ones the golden coquí lives in. Unfortunately, the golden coquí is also critically endangered and may actually be extinct. No one has seen one since 1981.

Most species of coquí lay their eggs on leaves instead of in water. The eggs still need to stay moist, though, so in many species the male will bring water to the eggs. He does this by just dunking himself in water, then returning to the leaf where the eggs are and plunking himself down on the eggs. He will also guard the eggs from potential predators. The eggs of all coquí species hatch into frogs instead of tadpoles.

A few species of coquí have been introduced to other parts of the world, either by accident or on purpose, and have become invasive species. This is especially true in Hawaii, where the coquí has become incredibly common and as a result is causing some native frogs to decline in numbers, along with other animals. But in Puerto Rico, where the coquí belongs, people are naturally proud of their loud little frogs. The indigenous people of Puerto Rico, the Taíno, incorporated the frog into their legends, and there’s even 700-year-old cave art on nearby Mona Island that includes paintings of coquí frogs.

The coquí frog mostly eats small invertebrates, including lots of cockroaches and other beetles, so they’re good to have around. Unfortunately, as is the case with so many frog species around the world, their numbers are in decline due to habitat loss, climate change, pollution, introduced predators, and a deadly fungus that we talked about in episode 250. Studies have shown that some populations of the coquí show a natural resistance to the fungus, so if we can just protect their habitats, the frogs will be okay.

Next, Henry wanted to learn more about the glass frog, which lives in Central and South America. We’ve talked about it very briefly in episode 148 and a couple of old Patreon episodes, but we’ve never really gone in-depth about it. Let’s do that now, because this is a really weird and interesting frog!

The glass frog lives in forests of Central and South America, mostly in treetops. They’re small frogs, no longer than about three inches, or 7.5 cm, from snout to vent. Most species are bright green, and in many species, the belly skin is almost completely transparent. You can see right through to their insides: guts, blood vessels, even bones. One newly discovered species from the Amazon also has a translucent chest so you can see its heart. In some species, even the organs are translucent. Some species even have green bones.

The blue-green color of the bones comes from high levels of biliverdin [bill-uh-ver-din] in the blood, which has evolved at least 40 times in 11 different frog families, with more species that have blue-green blood and bones discovered all the time.

In most animals, high levels of biliverdin are a result of liver disease, since it’s a toxin, but in these frogs, the biliverdin is retained in the blood instead of filtered out by the kidneys. Researchers think the biliverdin serves two purposes. Because it makes the frog green all the way through, it helps camouflage the frog among the leaves where it lives, even in infrared light. Researchers recently discovered that at least two species of glass frog reflect infrared light, which may also help keep them concealed from predators that can see in infrared. The high levels of biliverdin may also make the frog taste bad. Some researchers also think it may help protect the frog from parasites.

This doesn’t appear to be related to their see-through tummies, though. No one’s sure why glass frogs are see-through from underneath. Most species have green backs, which helps them blend in to the leaves they live on. Since the glass frog’s legs are usually partially transparent along with its belly, one study has determined that it’s actually the legs that help with camouflage. When the frog sits on a leaf with its legs folded up on either side, the way frogs often sit, the color of the leaf is partially visible through the legs. This helps make the frog look less frog-shaped since its edges sort of blend in with the leaf.

Most of the time glass frogs live high in the treetops, but during breeding season they come down closer to the ground. The female lays her eggs on leaves hanging over running water, which the male fertilizes. In some species, males guard the eggs until they hatch. When the eggs hatch, the tadpoles drop into the water.

Not all glass frogs have translucent undersides, though. Most are ordinary-looking frogs that may be green or occasionally brown or orangey in color, sometimes with little spots. There are also probably a whole lot more of these frogs than scientists know about, since they live in such hard-to-study areas. Several new species have been discovered in just the last few years, including one rediscovery of a species called Laura’s glass frog.

Until a few years ago, the only specimen of Laura’s glass frog was a male collected in 1955 in the foothills of the Andes Mountains in Ecuador. Then a team of scientists studying frogs in the Colonso-Chalupas Biological Reserve, also in Ecuador, found two frogs that weren’t familiar to them. One was male and the other a young female, both living near small creeks where lots of other frog species were common. They were green with tiny yellow spots surrounded by black rings, and were only a few centimeters long, or less than an inch. After several years of study, the team determined that the frogs were Laura’s glass frogs, and they published their findings almost exactly one year ago, in December 2021.

Hopefully, in 2023 scientists will discover and rediscover even more frog species, and we’ll be able to learn more about them so they and their habitats can be protected.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. 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 306: Two Million Years Ago in Greenland



This week we’re going to learn about a brand new study in Nature about animals and plants that lived in Greenland about two million years ago.

Happy birthday to Dillon!

Further reading:

A 2-million-year-old ecosystem in Greenland uncovered by environmental DNA

Scientists Reconstruct 2-Million-Year-Old Ecosystem from Environmental DNA

No bones? No problem: DNA left in cave soils can reveal ancient human occupants

Greenland now:

Greenland two million years ago [art by Beth Zaiken, taken from the second article linked above]:

Show transcript:

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

This week we’re going to do something a little different and talk about a new study just published in the journal Nature. A little section of this episode is taken from a recent Patreon episode, for those of you who listen and think, “Wait, I’m pretty sure I’ve heard that before.”

Before we get started, though, we have a birthday shoutout! A great big happy birthday to Dillon! I hope you do something really silly and fun on your birthday, like dance around wearing a ridiculous party hat and then eat cake.

Greenland is a big island off the eastern coast of Canada, but way far north, more or less in the Arctic. Even though it’s off the coast of North America, it’s considered part of Europe because for the last thousand years, it’s been controlled by Norway or Denmark at various times. Denmark’s got it right now. A little over 56,000 people live there today, most of them Inuit.

A big part of Greenland is covered in an ice sheet over a mile thick, which is so heavy it has pushed the central section of the island down so that it’s almost a thousand feet, or over 300 meters, below sea level. The land is much higher around the edges of the country. Basically Greenland is a gigantic bowl full of ice.

In 1966, the U.S. Army drilled into the ice to see what was under it, and the answer is dirt, as you might have expected. They took a 15-foot, or 4.5 meter, core sample and stuck it in a freezer, where everyone promptly forgot about it for 51 years. At some point it ended up in Denmark, where someone noticed it in 2017.

In 2019, the frozen core sample was finally studied by scientists. They expected to find mostly sand and rock. Instead, it was full of beautifully fossilized leaves and other plant material.

The main reason scientists were so surprised to find leaves and soil instead of just rock is that ice is really heavy, and it moves—slowly, but a mile-thick sheet of ice cannot be stopped. If you remember episode 277 about the rewilding of Scotland, you may remember that Scotland doesn’t have a lot of fossils from the Pleistocene because it was covered in glaciers that scoured the soil and everything in it down to bedrock, destroying everything in its path. But this hasn’t happened in Greenland.

Where the ice sheet now is, there used to be a forest. Obviously, the ice sheet hasn’t always covered Greenland. Research is ongoing, but a study of the sediment published in 2021 indicates that Greenland was ice free within the last million years, and possibly as recently as a few hundred thousand years.

If you go back a little farther, around two million years ago, Greenland was radically different. Not only was it ice free, it was much warmer than it is today. In north Greenland, which is now a polar desert, there was once an open forest where an incredible number of plants and animals lived. We know because of environmental DNA sequencing, often referred to as eDNA.

At this point most of us have a good understanding of what DNA is, but I’ll give you a quick explanation in case you’re not sure. DNA stands for Deoxyribonucleic acid, and it’s a polymer chain found in every organism’s cells that contains genetic instructions, essentially a guide on how to grow a particular type of animal. It’s way more complicated than that, but that gives you a basic idea. When cells replicate as an organism develops, either from an egg cell or a seed, the DNA directs what sequences of development happen at what stages. You inherit DNA from your parents but your personal DNA is always a little different from both parents’.

True crime podcasts talk about DNA a lot because every individual organism has a unique DNA profile, and since every single cell in our bodies contains DNA, criminals leave their unique signature at every crime scene. Now that scientists can sequence DNA from really tiny samples, many crimes have been solved when the only evidence was something like “this criminal murdered someone and then smoked a cigarette, and left the cigarette butt, and the DNA from their saliva on the cigarette butt was sequenced and run through a database of criminal DNA profiles, and now we know who the murderer is.” And then you get six commercials for mattresses and phone games.

But animal podcasts talk about DNA a lot because every species of organism has a unique genetic profile in addition to having a unique personal genetic profile. Scientists can retrieve DNA from a poop found in the forest and determine what species of animal left that poop. It probably wasn’t a Bigfoot. Scientists can also compare DNA from different animal populations to learn how closely related they are.

The most recent advance in DNA studies is environmental DNA, and it’s increasing our knowledge of the world in amazing ways. If you look at a lake, even if you go Scuba diving in the lake, even if you send a rover down to look at things in the lake, you won’t be able to see every single animal and plant and other organism that lives there. Fish are always moving around and may swim away from a diver or rover, or the water may be murky, and lots of animals stay hidden in the mud at the lake’s bottom. But if you take samples of the lake water and test it for DNA, suddenly you’re going to have more information than what you’d gather in days or weeks of just looking. Of course it’s important to observe animals in their natural habitats, but if you need to know whether an invasive species is living in the lake, or if an animal that hasn’t been seen for a long time is still extant in the lake, or if there are animals in the lake that no one’s ever seen before, eDNA can do that. The water is full of genetic material shed by different organisms.

It’s not just water, either, although testing water samples is pretty easy. DNA degrades quickly in ordinary circumstances, so while you can test soil to see what animals and plants live nearby, in most cases you’ll only find DNA that was deposited recently. But if the soil has been protected from sunlight, weather, and oxygen, such as soil found in a cave, there’s a chance that some ancient DNA can be found in it. That can tell us a lot about what animals lived in the cave a long time ago.

It’s not a few genetic sequences found in a single sample, either. As one scientist put it, there are trillions of DNA fragments in every single spoonful of dirt. Not all the samples are complete enough to sequence, but the ones that are can tell us a lot about the organisms that encountered that spoonful of dirt when it was at the surface of the cave. In Denisova Cave in Siberia, where a few remains of the Denisovan people were first discovered, researchers have learned that Denisovans and Neandertals lived in the cave for tens of thousands of years at different times, even though there aren’t any bones or artifacts remaining.

But the sediment from the Greenland eDNA study wasn’t from a cave. It had been preserved in permafrost for two million years without anything disturbing it, especially humans. It’s the oldest eDNA that’s been studied so far, more than a million years older than the previously oldest DNA. That was also found in permafrost and was recovered from a mammoth tooth.

Two million years ago in northern Greenland, poplar, birch, and thuja trees grew in an open forest along with various shrubs and other plants like ferns and moss. The thuja is sometimes called the tree of life or arborvitae and it’s an evergreen tree that’s related to junipers, sequoias, and cypresses. A lot of the plant DNA found was a surprise, since pollen from the plants had never been recovered in the area. Lots of plants related to modern roses and azaleas grew in the area, so we know there were flowers in spring and summer.

The area is called Kap København, and while it was still pretty cold, it was warm enough that much of the Greenland ice sheet had melted. In winter the temperature might have sometimes been as warm as 50 degrees Fahrenheit, or 10 Celsius, and only dipped to around 2 degrees Fahrenheit on average, or -17 Celsius. This is a whole lot warmer than modern days, where the winter temperature can drop to -50 Celsius, which is about the same in Fahrenheit, and almost never climbs above freezing except in summer.

Some of the animals that lived in the forest two million years ago were mastodons, reindeer, hares, geese, and various rodents related to voles and lemmings. There was even horseshoe crab DNA found from coastal water that had been pushed farther inland during flooding. All the animals found are related to modern animals that still live today, but only one, the Arctic hare, had actually been found in the fossil record in Greenland. They also found DNA of ants and fleas, plankton, algae, and lots of microbial life.

There is no ecosystem on earth today that quite matches that of Kap København from two million years ago. Until this study, scientists thought that not much lived in the area at the time, certainly not mastodons. Hopefully, environmental DNA can be recovered from even older sediments so we can learn more about the ancient world.

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 305: The Chamois and the Cave Goat



Thanks to Isaac for suggesting the chamois, our main topic this week!

Further reading:

The chamois in New Zealand

Extinct goat was cold-blooded

Myotragus balearicus: Extinction of mouse-goats

A chamois in its summer coat:

A chamois in its winter coat:

Myotragus, the “cave goat,” may have looked something like this museum restoration:

Nuralagus’s femur (left) compared to a regular rabbit femur:

Show Transcript:

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

This week we’re going to talk about an animal suggested by Isaac, the chamois, along with a few other animals. I realize we’ve talked about a lot of mammals lately so I’ll try to switch it up for the last few episodes of the year.

The chamois is a species of what are called goat-antelopes. Its name is French and is spelled c-h-a-m-o-i-s, but in English a lot of people pronounce it “shammy.” Shammy is also what people call polishing cloths of various types, because it’s short for chamois. If you ever heard those commercials on TV for something called the sham-wow, that’s a paper towel thingy that’s based on the shammy cloth. The reason for all this confusion between an animal and a cloth is that the original shammy cloth was a piece of leather from the animal that was used to polish high-quality items like fancy cars since it’s very soft and won’t scratch anything. Most shammy cloths you buy these days are likely to be made from plush cloth or the skin of domestic goats or sheep.

As for the animal, it’s native to mountainous parts of Europe, including the Alps. It’s also been introduced to New Zealand’s South Island where it’s an invasive species that threatens many native plants. Since chamois meat is considered a delicacy, commercial hunters in New Zealand travel into the mountains by helicopter, kill as many of the animals as possible, and bring the meat back to sell to restaurants. This is encouraged by the New Zealand government in an attempt to protect native plants, although red deer, feral goats, and hares are also introduced animals that do a lot of damage to the delicate mountain environment.

The chamois is small, only about two and a half feet tall at the shoulder, or 80 cm. It has cloven hooves and both males and females have small black horns. The horns are mostly straight but bend backwards at the tips into a sort of hook shape, and while males have thicker horns, they aren’t usually that much longer than the female’s. Horns grow up to 11 inches long, or 28 cm.

In summer the chamois’s fur is light brown with a darker stripe on each side of the face that runs from the nostrils, over the eyes, and up to the horns. In winter its fur grows very thick to keep it warm in its mountainous habitat, and it’s a much darker brown, almost black. It still has the dark band on its face with lighter colored fur on its cheeks and jaw, though. Its tail is very short and isn’t usually visible.

Female chamois live in small groups along with their offspring. Males are solitary most of the year, but during mating season in autumn and early winter, called the rut, males fight each other for the attention of females. The female gives birth to a single kid in late spring. In the winter the chamois migrates to lower elevations where there’s more food, but in summer it migrates to high elevations above the treeline where it’s safer from predators. It can run extremely fast, up to about 30 miles per hour, or 50 km/hour, and can jump as much as 20 feet, or 6 meters. It can even jump over six and a half feet high, or 2 meters, straight up. It’s very bouncy.

I mentioned that the chamois is a goat-antelope, so let’s go back to that term. The goat-antelope isn’t actually a type of antelope, although it is an antelope relation. Goat-antelopes are bovids, along with antelopes, actual goats, sheep, cows, and many others. The goat-antelopes are members of the subfamily Caprinae, which includes goats, sheep, musk ox, mountain goats, takins, and many other interesting animals that we need to talk about one day. One of these is the extinct Myotragus, called the mouse goat or the Balearic Islands cave goat because the first fossils were found in a cave. It didn’t actually live in caves, although it was weird in other ways.

The cave goat was a small animal, only about 18 inches tall, or 46 cm, and both males and females had small horns that probably looked like a goat’s horns. Like most other goat-antelopes, researchers think the cave goat was a browser that ate lots of different kinds of plants, although its ancestors had probably been grazers that ate mostly grass. But its eyes were oriented for binocular vision like a predator’s eyes, instead of being on the sides of its head as in most herbivores, which allows an animal a much wider range of vision to watch for predators. Since the cave goat had lived on islands for several million years and didn’t need to worry about large predators, it didn’t need the adaptations that other prey animals have. For instance, it probably was a slow walker and couldn’t jump at all, sort of the opposite of the chamois.

An analysis of the rate of growth in the cave goat’s bones discovered something really weird. Most mammals grow quickly and steadily throughout their youth and then stop growing when they reach adulthood. The cave goat grew very slowly and sometimes stopped growing completely for a while, and didn’t reach full maturity where growth stopped until it was about 12 years old. Most goat-antelope species reach their full size within a year or two. This pattern resembles that of a reptile, not a mammal, and researchers think it was an adaptation to its restricted habitat. An island only has so much food available at any given time, so being able to slow or stop growing for a while when food is scarce, then resume growing when there’s more food to convert to energy, is an efficient way to deal with scarcity. When the finding was published in 2009, a lot of articles called the cave goat cold-blooded, or ectothermic, but we don’t actually know if this was the case.

The cave goat went extinct around 3,000 years ago when humans arrived on the islands where it lived. But instead of ending on that sad note, let’s look very quickly at another animal that lived on the same islands before the cave goat. It was a gigantic weird rabbit called Nuralagus rex.

Nuralagus was a rabbit but due to island gigantism, it was way larger than an ordinary rabbit and would have looked very different. It was about 20 inches tall at the highest point of its back, or 50 cm. Like the cave goat but unlike other rabbits, it couldn’t jump. Its spine was stiff and there weren’t very many predators to worry about, so it could just walk around and find plants and other giant bunnies and that’s all it needed. It didn’t have very good hearing compared to most rabbits, so its ears were probably much shorter in relation to its body. It was only described in 2011, which just goes to show how many weird animal discoveries are still waiting to be found.

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 304: Animals of the Paleogene



Thanks to Pranav for suggesting this week’s topic, animals of the Paleogene, the period after the Cretaceous! Thanks also to Llewelly for suggesting the horned screamer, now one of my favorite birds.

Further watching:

Southern Screamers making noise

Horned Screamers making noise

Further reading:

The Brontotheres

Presbyornis looked a lot like a long-legged goose [art by Smokeybjb – CC BY-SA 3.0]

The southern screamer (left) and horned screamer (right), probably the closest living relation to Presbyornis:

Megacerops was really really big:

All four of these illustrated animals are actually megacerops, showing the variation across individuals of nose horn size:

Uintatherium had a really weird skull and big fangs:

Pezosiren didn’t look much like its dugong and manatee descendants:

Show transcript:

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

This week we’re going to look at some strange animals of the Paleogene period, a suggestion from Pranav. Pranav also suggested the naked mole-rat that we talked about in episode 301, but I forgot to credit him in that one.

As we talked about in episode 240, about 66 and a half million years ago, a massive asteroid smashed into the earth and caused an extinction event that ended the era of the dinosaurs. The geologic time period immediately after that event is called the Paleogene, and paleontologists study this era to learn how life rebounded after the extinction event. We’re going to learn about a few animals that evolved to fill ecological niches left vacant after dinosaurs went extinct.

These days, mammals fill a whole lot of these ecological niches, so it’s easy to assume that mammals have been successful for the last 66 million years. But while that’s true now, birds were incredibly successful for a long time. Basically for millions of years after the non-avian dinosaurs died out, it was dinosaurs 2.0 as the avian dinosaurs, better known as birds, spread throughout the world and evolved into some amazing organisms.

This included terror birds, which we talked about in episode 202. They lived in South America, except for one species from North America, and evolved really soon after the dinosaurs went extinct, appearing in the fossil record about 60 million years ago. They lasted a long time, too, only going extinct around 2 million years ago.

The earliest known terror bird was about three feet tall, or 91 cm, but its descendants became larger and more fearsome until they were apex predators throughout South America. The biggest species grew up to ten feet tall, or three meters, with a massive beak and sharp claws on its toes. It couldn’t fly but was a fast runner. You would not want a terror bird chasing you.

Lots of other birds evolved throughout the Paleogene, but most of them would look pretty familiar to us today. Paleontologists have found fossils of the ancestors of many modern birds, including penguins, hummingbirds, and parrots, which shows that they were already specialized some 25 or 35 million years ago or even more. In the case of penguins, we have fossils of penguin ancestors dating back to the late Cretaceous, before the extinction event. Those ancient penguins could probably still fly, but it didn’t take too long to evolve to be a fully aquatic bird. The species Waimanu manneringi lived around 62 million years ago in what is now New Zealand. It resembled a loon in a lot of ways, with its legs set well back on its body, and it probably spent much of its time floating on the water between dives. But unlike a loon, it had lost the ability to fly and its wings were already well adapted to act as flippers underwater.

Another bird would have looked familiar at first glance, but really weird when you gave it a second look. Presbyornis lived between about 62 and 55 million years ago in what is now North America, and it lived in flocks around shallow lakes. It was the size of a swan or goose and mostly shaped like a goose, with a fairly chonky body and a long neck. It had a large, broad duckbill that it used to filter small animals and plant material from the water and its feet were webbed…but its legs were really long, more like a heron’s legs.

When the first Presbyornis fossils were found in the 1920s, the scientists thought they’d found ancient flamingos. But when a skull turned up, Presbyornis was classified with ducks and geese. It wasn’t very closely related to modern ducks and geese, though. Researchers now think its closest modern relation is a South American bird called the screamer. Llewelly suggested the horned screamer a long time ago and now that I have learned more about these birds, I love them so much!

The screamer looks sort of like a goose but has long, strong legs and a sharp bill more like a chicken’s. It lives in marshy areas and eats pretty much anything, although it prefers plant material. It has two curved spurs that grow on its wings that it uses to defend its territory from predators or other screamers, and if a spur breaks off, which it does pretty often, it grows back. The screamer mates for life and both parents build the nest together and help take care of the eggs and chicks when they hatch.

The horned screamer has a long, thin structure that grows from its forehead and looks sort of like a horn, although it’s not a horn. It’s wobbly, for one thing, but it’s also not a wattle. It grows throughout the bird’s life and may break off at the end every so often, and it’s basically unlike anything seen in any other bird. Maybe presbyornis had something similar, who knows?

The screamer gets its name from its habit of screaming if it feels threatened or if it just encounters something new or that it doesn’t like. The screaming is actually more of a honking call that sounds like this:

[screamer call]

People sometimes raise screamers with chickens to act as guard birds. It can run fast but it can swim faster, and it can also fly although it doesn’t do so very often. Although it’s distantly related to ducks, its meat is spongy and full of air sacs that help keep it afloat in the water, so people don’t eat it. It is vulnerable to habitat loss, though.

One organism that evolved early in the Paleogene was grass. You know, the plant that a whole lot of animals eat. There are lots and lots of different types of grass, not just the kind we’re used to mowing, and as the Paleogene progressed, it became more and more widespread. But it wasn’t as ubiquitous as it is now, so even though the ancestors of modern grazing animals evolved around the same time, they weren’t grazers yet. The word graze comes from the word grass, but ancient ancestors of horses and other grazing animals were still browsers. They ate all kinds of plants, and didn’t specialize as grazers until grasses really took off and huge grasslands developed in many parts of the world, around 34 million years ago.

Because the Paleogene lasted so long, between about 66 and 23 million years ago, there’s literally no way we can talk about more than a few animals that lived during that time, not in a single 15-minute episode. We’ve also covered a lot of Paleogene animals in previous episodes, like paraceratherium in episode 50, the largest land mammal known. It probably grew up to about 16 feet tall at the shoulder, or 5 meters, and taller if you measured it at the top of its head. Other examples are moeritherium, an ancient elephant relation we talked about in episode 18, the giant ground sloth that we talked about in episode 22, and the ancient whale relation basilosaurus that we talked about in episode 132. Patrons also got a bonus basilosaurid episode this month. But I’m pretty sure we’ve never talked about brontotheres.

Brontotheres first appear in the fossil record around 56 million years ago and they lived until at least 34 million years ago. All animals in the family Brontotheriidae are extinct, but they were closely related to horses. They didn’t look like horses, though; they looked a lot like weird rhinoceroses, although remember that rhinos are also related to horses. They were members of the odd-toed ungulates, along with tapirs and the gigantic Paraceratherium.

Fossil remains of brontotheres have been found in North America, a few parts of eastern Europe, and Asia, although they might have been even more widespread. The earliest species were only about three and a half feet tall at the shoulder, or about a meter, but later species were much larger. While they looked a lot like rhinos, they didn’t have the kind of keratin hose horns that rhinos have. Instead, some species had a pair of horns made of bone that varied in shape and size depending on species. The horns were on the nose as in rhinos, but were side-by-side.

Brontotheres developed before grasslands became widespread, and instead they were browsers that mostly ate relatively soft vegetation like leaves and fruit. Grass is really tough and animals had to evolve specifically to be able to chew and digest it. In fact, the rise of grasslands as the climate became overall much drier around 34 million years ago is probably what drove the brontotheres to extinction. They lived in semi-tropical forests and probably occupied the same ecological niche that elephants do today. This was before elephants and their relations had evolved to be really big, and brontotheres were the biggest browsing animals of their time.

Brontotheres probably lived in herds or groups of some kind. They were widespread and common enough that they left lots of fossils, so many that they were found relatively often in North America even before people knew what fossils were. The Sioux Nation people were familiar with the bones and called them thunder horses. When they were scientifically described in 1873 by Othniel Marsh, he named them after the Sioux term, since brontotherium means “thunder beast.”

Two of the biggest brontotheres lived at about the same time as each other, around 37 to 34 million years ago. Megacerops lived in North America while Embolotherium lived in Asia, specifically in what is now Mongolia. Megacerops is the same animal that’s sometimes called brontotherium or titanotherium in older articles and books.

Megacerops and Embolotherium were about the same size, and they were huge, although Embolotherium was probably just a bit larger than Megacerops. They stood over 8 feet tall at the shoulder, or 2.5 meters, and were more than 15 feet long, or 4.6 meters. This is much larger than any rhinos alive today and as big as some elephants. Their legs would probably have looked more like an elephant’s legs than a rhinoceros’s.

Brontothere nose horns weren’t true horns, since they don’t seem to have been covered with a keratin sheath, but they were formed from protrusions of the nasal bones. They might have been more like ossicones, covered with skin and hair. Megacerops had a pair of nose horns that were much larger in some individuals than others, and scientists hypothesize that males had the larger horns and used them to fight each other.

But this can’t have been the case for embolotherium. It had even bigger nose horns that were fused together in a wedge-shaped plate sometimes referred to as a ram, but they contained empty chambers inside that were a continuation of the nasal cavities. They wouldn’t have been strong enough to bash other embolotheriums with, but they might have acted as resonating chambers, allowing embolotherium to communicate with loud sounds. All individuals had these nose horns, even juveniles, and they were all about the same size, which further suggests that they had a purpose unrelated to fighting.

At about the same time the brontotheres were evolving, another big browsing animal also lived in what are now China and the United States. Two species are known, one in each country, and both stood about 5 feet tall at the shoulder, or 1.5 meters. It looked sort of like a brontothere in some ways, but very different in other ways, especially its weird skull, and anyway it was already big around 56 million years ago when brontotheres were still small and unspecialized.

Scientists aren’t sure what uintatherium was related to. It’s been placed in its own genus, family, and order, although some other uintatherium relations have been discovered that share its weird traits. Most scientists these days think it was probably an ungulate.

Uintatherium’s skull was extremely strong and thick, which didn’t leave a whole lot of room for brains. But what uintatherium lacked in brainpower, it made up for in sheer defensive ability. It had huge canine teeth that hung down like a sabertooth cat’s fangs, although males had larger fangs than females. Males also had three pairs of ossicones or horns on the top of the skull that pointed upwards. One pair was on the nose, one pair over the eyes, and one pair almost on the back of the skull. They could be as much as 10 inches long, or 25 cm, and paleontologists think that males wrestled with these horns the same way male deer will lock antlers and wrestle.

Uintatherium lived in the same habitat and probably ate more or less the same type of plants that later brontotheres did. They went extinct around the time that brontotheres evolved to be much larger, which suggests that brontotheres may have outcompeted uintatherium.

We’ll finish with one more Paleogene mammal, Pezosiren. It was only described in 2001 from several incomplete specimens discovered in Jamaica in the 1990s, and it lived between 49 and 46 million years ago.

Pezosiren was about the size of a pig, although it had a longer, thicker tail compared to pigs. It wasn’t any kind of pig, though, and in fact it was distantly related to elephants. It was the oldest known ancestor of modern sirenians. Pezosiren is also called the walking siren, because it still had four legs and probably spent at least part of the time on land, although it could swim well. Scientists think it probably swam more like an otter than a sirenian, propelling itself through the water with its hind legs instead of its tail.

Pezosiren was probably semi-aquatic, sort of like modern hippos, and already shows some details specific to sirenians, especially its heavy ribs that would help it stay submerged when it wanted to. It ate water plants and probably stayed in shallow coastal water. At different times in the past, Jamaica was connected to the North American mainland or was an island on its own as it is now, or occasionally it was completely submerged. About 46 million years ago it submerged as sea levels rose, and that was the end of Pezosiren as far as we know. But obviously Pezosiren either survived in other areas or had already given rise to an even more aquatic sirenian ancestor, because while Pezosiren is the only sirenian known that could walk, its descendants were well adapted to the water. They survive today as dugongs and manatees.

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!