Category Archives: Africa

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 301: Hairless Mammals



Thanks to Liesbet for this week’s suggestion, about two mammals that have evolved to be hairless!

Happy birthday this week to Declan and Shannon!

The hairless bat has a doglike face and a doglike tail but (and this is important) it is not a dog [photos from this site]:

The naked mole-rat’s mouth is behind its teeth instead of the usual “my teeth are in my mouth” kind of thing:

Show transcript:

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

This week we have a suggestion from Liesbet, who asked about furless animals. We’re going to learn about two mammals that don’t have fur, and they’re not ones you may be thinking of.

But first, we have two birthday shout-outs! Happy birthday to Declan and Shannon! I hope both your birthdays are so amazing that whatever town you live in finishes off the day by giving you the key to the city. What do you do with the key? I don’t know, but it sounds like something to brag about.

Mammals are famous for having hair, but not all mammals actually have hair. Cetaceans like whales and dolphins have lost all their hair during their evolution into marine animals, although before a baby whale is born it has a little bit of fuzzy hair on its head. Other mammals, like humans, pigs, walruses, and elephants, have evolved to only have a little hair. There are also domesticated mammals that have been bred to have no hair, like sphynx cats and Chinese crested dogs.

There are other domesticated hairless mammals, though, including two types of guinea pig. The skinny pig only has a little bit of fuzzy hair on its face and ears, while the baldwin pig only has a tuft of hair on its nose. But the animals we’re going to talk about today are hairless animals you may not have heard of.

For instance, the hairless bat, which lives in parts of Southeast Asia. Its dark gray body is almost completely hairless, although it does sometimes have little patches of fuzz on the head and tail, and longer bristles around the neck. It’s nocturnal and eats insects, but since it’s a fairly large bat, around 6 inches long, or 15 cm, it can eat fairly large insects. It especially likes grasshoppers, termites, and moths.

The hairless bat roosts in colonies of up to a thousand individuals, and it lives in caves, hollow trees, or rock crevices. Although it uses echolocation, it doesn’t have a nose leaf like many microbats have, but instead has a little doglike snout. Its tail is skinny like a little dog’s tail instead of being connected to the hind legs or body by patagia. It has a little throat pouch that secretes strong-smelling oil.

It also has a sort of pocket on either side of the body. Originally people thought that mother bats used these pouches to carry their babies, since hairless bats usually have two babies at a time. Instead, it turns out that mother bats leave their babies at home when they go out to hunt, and the pockets are used for something else. The pockets are formed by a fold of skin and the end of the wing fingers and membranes fit into them. The bat uses its hind feet to push the wings into the pockets, sort of like stuffing an umbrella into the little cover that it comes in when you first buy it. This allows the bat to run around on all fours without its wings getting in the way. Since most bats can’t walk on all fours at all, this is pretty amazing.

Our other hairless animal today is the naked mole-rat, which is not a mole or a rat. It is a type of rodent but it’s more closely related to porcupines than to rats. It lives in tropical grasslands in parts of East Africa and spends almost its entire life underground. It lives in colonies of up to 300 individuals, and the colony’s tunnels and nesting burrows are extensive, often covering up to 3 miles, or 5 km. It eats roots of plants and the colony carefully only eats part of each root so that they don’t kill the plant. The roots continue to grow, providing the colony with lots of food.

The naked mole-rat grows about 4 inches long, or 10 cm, although dominant females are larger. It has tiny eyes and doesn’t see very well, since most of the time it doesn’t need to see, and it has a chonky body but short, spindly legs. It pretty much has no hair except for whiskers and some tiny hairs between the toes, and its skin is so pale it’s almost translucent. It digs with its protruding front teeth, and these teeth are not in its mouth. They grow out through the skin and the animal’s mouth is actually behind the teeth. This way the mole-rat can dig without getting dirt in its mouth, but it sure looks weird to us.

But that’s not even close to the weirdest thing about the naked mole-rat. We haven’t even scratched the surface of weirdness!

The naked mole-rat lives underground in a part of the world where it’s always warm, and its tunnel system has no exits to the surface except for temporary exits when new tunnels are being excavated, because the dirt has to go somewhere. Its environment is so consistent in temperature that it doesn’t need to regulate its body temperature like every other mammal known. It’s ectothermic, which is sometimes called cold-blooded. Reptiles and amphibians are ectothermic but all other mammals known are endothermic. It’s kind of our thing. But the naked mole-rat is different. Its metabolism is extremely low, and as a result it can live for more than 30 years when most rodents the same size are lucky to live 2 or 3 years.

The naked mole-rat’s skin isn’t just hairless, it also lacks neurotransmitters. This means its skin doesn’t feel pain. The animal also lives in an environment that’s remarkably low in oxygen, and scientists think this contributes to the fact that the mole-rat never shows evidence of cancer except in captivity where its environment is higher in oxygen.

The naked mole-rat’s colony is led by a dominant female, called a queen, and she’s the only female in the colony that has babies. When a female achieves dominance, either by founding a new colony, taking over after the current queen dies, or defeating the current queen in a fight, she then grows larger and becomes able to reproduce. Only a few males in the colony mate with her. All the other members of the colony are unable to reproduce. They’re considered workers and help take care of the queen’s babies, maintain tunnels, forage for food, or act as soldiers to keep snakes and other predators out. If this sounds like the way some insect colonies are structured, especially bees and ants, you’re right. It’s called eusociality and the mole-rat is the only type of mammal known with this sort of social structure. There’s another type of mole-rat from southern Africa that’s also eusocial, but it has fur.

All that is so weird that I almost forgot the mole-rat is hairless. That now seems like the most normal thing about it.

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

Thanks for listening!


Episode 292: The Kunga



This week let’s learn about a mystery that was solved by science!

Happy birthday to Zoe!

Further reading:

Let’s all do the kunga!

The kunga, as depicted in a 4500-year-old mosaic:

The Syrian wild ass as depicted in a 1915 photograph (note the size of the animal compared to the man standing behind it):

Domestic donkeys:

Show transcript:

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

As this episode goes live, I should be on my way home from Dragon Con, ready to finish moving into my new apartment! It’s been an extremely busy week, so we’re just going to have a short episode about a historical mystery that was recently solved by science.

But first, we have another birthday shout-out! Happy birthday to Zoe, and I hope you have the most sparkly and exciting birthday ever, unless you’d rather have a chill and low-key birthday, which is just as good depending on your mood.

This week we’re going to learn about an animal called the kunga, which I learned about on Dr. Karl Shuker’s blog. There’s a link in the show notes if you’d like to read his original post.

The mystery of the kunga goes back thousands of years, to the fertile crescent in the Middle East. We’ve talked about this area before in episode 177, about the sirrush, specifically Mesopotamia. I’ll quote from that episode to give you some background:

“These days the countries of Iraq and Kuwait, parts of Turkey and Syria, and a little sliver of Iran are all within what was once called Mesopotamia. It’s part of what’s sometimes referred to as the Fertile Crescent in the Middle East. The known history of this region goes back five thousand years in written history, but people have lived there much, much longer. Some 50,000 years ago humans migrated from Africa into the area, found it a really nice place to live, and settled there.

“Parts of it are marshy but it’s overall a semi-arid climate, with desert to the north. People developed agriculture in the Fertile Crescent, including irrigation, but many cultures specialized in fishing or nomadic grazing of animals they domesticated, including sheep, goats, and camels. As the centuries passed, the cultures of the area became more and more sophisticated, with big cities, elaborate trade routes, and stupendous artwork.”

The domestic horse wasn’t introduced to this area until about 4,000 years ago, although donkeys were common. The domestic donkey is still around today, of course, and is descended from the African wild ass. Researchers estimate it was domesticated 5- or 6,000 years ago by the ancient nomadic peoples of Nubia, and quickly spread throughout the Middle East and into southern Asia and Europe.

But although horses weren’t known in the Middle East 4,500 years ago, we have artwork that shows an animal that looks like a really big donkey, much larger than the donkeys known at the time. It was called the kunga and was highly prized as a beast of burden since it was larger and stronger than an ordinary donkey. It was also rare, bred only in Syria and exported at high prices. No one outside of Syria knew what kind of animal the kunga really was, but we have writings that suggest it was a hybrid animal of some kind. This explains why its breeding was such a secret and why it couldn’t be bred elsewhere. Many hybrid animals are infertile and can’t have babies.

If the artwork was from later times, we could assume it showed mules, the offspring of a horse and a donkey. But horses definitely weren’t known in the Middle East or nearby areas at this time, so it can’t have been a mule.

The kunga was used as a beast of burden to pull plows and wagons, but the largest individuals were used to pull the chariots of kings. Fortunately, the kunga was so highly prized that it was sometimes sacrificed and buried with important people as part of their grave goods. Archaeologists have found a number of kunga skeletons, together with ceremonial harnesses. Unfortunately, it’s actually difficult to tell the difference between the skeletons of various equids, including horses, donkeys, zebras, and various hybrid offspring like mules. All scientists could determine is that the kunga most closely resembled various species and subspecies of donkey.

In January 2022, the mystery was finally solved. A genetic study of kunga remains was published that determined that the kunga was the offspring of a female domesticated donkey and a male Syrian wild ass.

The Syrian wild ass was native to many parts of western Asia. It was barely more than three feet tall at the shoulder, or about a meter, and while it was admired as a strong, beautiful animal that was sometimes hunted for its meat and skin, it couldn’t be tamed.

Because the Syrian wild ass was a different species of equid from the domesticated donkey, and because it couldn’t be tamed and was hard to catch, breeding kungas would be difficult. Male wild asses had to be captured, probably when young, and kept with female donkeys in hopes that they would mate eventually and offspring would result. Obviously the kunga showed what’s called hybrid vigor, where a hybrid is stronger than either of its parents, but because it was also infertile, the largest and strongest kungas couldn’t be bred together. Each kunga had to be bred from a pairing of wild ass and domestic donkey. No wonder it was expensive!

When the horse was introduced to the Middle East, it took the place of the kunga quickly and before long everyone had forgotten what the kunga even was.

Sadly, we can’t try to breed a kunga today to see what it was really like, because the Syrian wild ass went extinct in 1927. But the endangered Persian wild ass was introduced to parts of the Middle East starting in 2003, including Saudi Arabia, Iran, and Israel, to take the place of its extinct Syrian relation, and its numbers are increasing.

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 291: The Ediacaran Biota



This week let’s find out what lived before the Cambrian explosion!

A very happy birthday to Isaac!

Further reading:

Some of Earth’s first animals–including a mysterious, alien-looking creature–are spilling out of Canadian rocks

Say Hello to Dickinsonia, the Animal Kingdom’s Newest (and Oldest) Member

Charnia looks like a leaf or feather:

Kimberella looks like a lost earring:

Dickinsonia looks like one of those astronaut footprints on the moon:

Spriggina looks like a centipede no a trilobite no a polychaete worm no a

Glide reflection is hard to describe unless you look at pictures:

Trilobozoans look like the Manx flag or a cloverleaf roll:

Cochleatina looked like a snail:

Show transcript:

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

It’s the last week of August 2022, so let’s close out invertebrate August with a whole slew of mystery fossils, all invertebrates.

But first, we have a birthday shoutout! A humongous happy birthday to Isaac! Whatever your favorite thing is, I hope it happens on your birthday, unless your favorite thing is a kaiju attack.

We’ve talked about the Cambrian explosion before, especially in episode 69 about some of the Burgess shale animals. “Cambrian explosion” is the term for a time starting around 540 million years ago, when diverse and often bizarre-looking animals suddenly appear in the fossil record. But we haven’t talked much about what lived before the Cambrian explosion, so let’s talk specifically about the Ediacaran (eedee-ACK-eron) biota!

I was halfway through researching this episode when I remembered I’d done a Patreon episode about it in 2021. Patrons may recognize that I used part of the Patreon episode in this one. You’d think that would save me time but surprise, it did not.

The word Ediacara comes from a range of hills in South Australia, where in 1946 a geologist noticed what he thought were fossilized impressions of jellyfish in the rocks. At the time the rocks were dated to the early Cambrian period, and this was long before the Cambrian explosion was recognized as a thing at all, much less such an important thing. But since then, geologists and paleontologists have reevaluated the hills and determined that they’re much older than the Cambrian, dating to between 635 to 539 million years ago. That’s as much as 100 million years before the Cambrian. The Ediacaran period was formally designated in 2004 to mark this entire period of time, although fossils of Ediacaran animals generally start appearing about 580 million years ago.

Here’s something interesting, by the way. During the Ediacaran period, every day was only 22 hours long instead of 24, and there were about 400 days in a year instead of 365. The moon was closer to the earth too. And life on earth was still sorting out the details.

Fossils from the Ediacaran period have been discovered in other places besides Australia, including Namibia in southern Africa, Newfoundland in eastern Canada, England, northwestern Russia, and southern China. Once the first well-preserved fossils started being found, in Newfoundland in 1967, paleontologists started to really take notice, because they turned out to be extremely weird. The fossils, not the paleontologists.

Many organisms that lived during this time lived on, in, or under microbial mats on the sea floor or at the bottoms of rivers. Microbial mats are colonies of microorganisms like bacteria that grow on surfaces that are either submerged or just tend to stay damp. Microbial mats are still around today, usually growing in extreme environments like hot springs and hypersaline lakes. But 580 million years ago, they were everywhere.

One problem with the Ediacaran biota, and I should explain that biota just means all the animals and plants that live in a particular place, is that it’s not always clear if a fossil is actually an animal. Many Ediacaran fossils look sort of plant-like. At this stage, the blurry line between animals and plants was even more blurry than it is now, with the added confusion that sometimes non-organic materials can resemble fossils, and vice versa.

For instance, the fossil Charnia, named after Charnwood Forest in England where it was first discovered. In 1957, a boy named Roger, who was rock-climbing in the forest, found a fossil that looked like a leaf or feather. He took a rubbing of the fossil and showed his father, who showed it to a geologist. The year before, in 1956, a 15-year-old girl named Tina saw the same fossil and told her teacher, who said those rocks dated to before the Cambrian and no animals lived before the Cambrian, so obviously what she’d found wasn’t a fossil.

Tina’s teacher was wrong about that, of course, although he was correct that the rocks dated to before the Cambrian, specifically to about 560 million years ago. But while Charnia looks like a leaf, it’s not a plant. This was about 200 million years before plants evolved leaves, and anyway Charnia lived in water too deep for plants to survive. It anchored itself to the sea floor on one end while the rest of the body stuck up into the water, and some specimens have been found that were over two feet long, or 66 cm. Some researchers think it was a filter feeder, but we have very little evidence one way or another.

One common animal found in Australia and Russia is called Kimberella, which lived around 555 million years ago and might have been related to modern mollusks or to gastropods like slugs. It might have looked kind of like a slug, at least superficially. It grew up to 6 inches long, or 15 cm, 3 inches wide, or 7 cm, and an inch and a half high, or 4 cm, which was actually quite large for most animals that lived back then. It was shaped roughly like an oval, with one thin end that stuck out, potentially showing where its front end was, although it didn’t have a head the way we think of it today. The upper surface of its body was protected by a shell, but not the type of shell you’d find on the seashore today. This was a flexible, non-mineralized shell, basically just thick, toughened tissue with what may be mineralized nodules called sclerites embedded in it. All around its body was a frill that might have acted as a gill. The underside of Kimberella was a flat foot like that of a slug.

We know Kimberella lived on microbial mats on the sea floor, and it might have had a feeding structure similar to a radula. That’s because it’s often found associated with little scratches on its microbial mat that resemble the scratches made by a radula when a slug or related animal is feeding on a surface. The radula is a tongue-like organ studded with hard, sharp structures that the animal uses to scrape tiny food particles from a surface.

Kimberella displays bilateralism, meaning it’s the same side to side. That’s the case with a lot of modern animals, including all vertebrates and a lot of invertebrates too, like insects and arachnids. But other Ediacarans showed radically different body plans. Charnia, for instance, exhibits glide reflection, where both sides are the same as in bilateralism, but the sides aren’t exactly opposite each other. If you walk along a beach and make footprints in the sand, your trail of footprints actually demonstrates glide reflection. If you stand on the sand and jump forward with both feet together, your footprints demonstrate bilateralism since the prints are side by side. (This is confusing to describe, sorry.) Pretty much the only living animals with this body pattern are some sea pens, which get their name because they resemble old-fashioned quill pens. Many sea pens look like plants, and for a long time researchers thought Charnia might be an ancient relation to the sea pen. These days most researchers are less certain about the relationship.

A similar-looking animal that lived around the same time as Charnia was Dickinsonia. It looks sort of like a leaf too, but a more broad oval-shaped leaf instead of a long thin one like Charnia. It’s also not a leaf. Some are only a few millimeters long, but some are over 4 1/2 feet long, or 1.4 meters.

Dickinsonia may be related to modern placozoans, a simple squishy creature only about one millimeter across. It travels very slowly across the sea floor and absorbs nutrients from whatever organic materials it encounters. But we don’t know if Dickinsonia was like that or if it was something radically different. Until a few years ago a lot of paleontologists thought Dickinsonia might be some kind of early plant or algae. Then, in 2016, a graduate student discovered some Dickinsonia fossils that were so well preserved that researchers were able to identify molecular information from them. They found cholesteroids in the preserved cells, and since only animals produce cholesteroids, Dickinsonia was definitely an animal. But that’s still about all we know about it so far.

Spriggina is another animal that at first glance looks like a leaf or feather. Then it sort of resembles a trilobite, or a segmented worm, or a possible relation to Dickinsonia. It looks like all sorts of animals but doesn’t really fit with anything known. It grew up to two inches long, or 5 cm, and had what’s referred to as a head shield although we don’t know for sure if it was actually its head. The head shield might have had eyes and might have had some kind of antennae, and some fossils seem to show a round mouth in the middle of the head, but it’s hard to tell. The rest of its body was segmented in rings. What Spriggina didn’t have was legs, or at least none of the fossils found so far show any kind of legs. Some species of Spriggina show a glide reflection body plan, while others appear to show a more ordinary bilateral body plan.

Three Ediacaran animals have such a weird body plan that they’ve been placed in their own phylum, Trilobozoa, meaning three-lobed animals. They show tri-radial symmetry, meaning that they have three sections that are identical radiating out from the center. They lived on microbial mats and were only about 40 mm across at most, which is about an inch and a half. Tribrachidium was roughly round in shape although its relations looked more like tiny cloverleaf rolls. Cloverleaf rolls are made by putting three little round pieces of dough together and baking them so that the roll has three lobes, although Trilobozoans probably didn’t taste as good. Also, Trilobozoans were covered with little grooves from center to edge and had three curved ridges, one on each lobe. The ridges were originally interpreted as arms or tentacles, but they seem to have just been ridges. Researchers think the little grooves directed water over the body’s surface and the ridges acted as tiny dams that slowed the water down just enough that particles of food carried in the water would fall onto the body so that the animal could absorb the nutrients, although we don’t know how that worked.

Many other Ediacaran animals had radial symmetry like modern echinoderms and jellyfish, including the ancestors of jellyfish. Some Ediacaran animals even had shells of various kinds, and they’re generally referred to as small shelly fossils. They were rarely more than a few millimeters across at most and are sometimes found mixed in with microbial mats. Cochleatina, for instance, is less than a millimeter across and all we know about it is that it had a ribbon-like spiral shell like a really simple snail’s shell. It wasn’t a snail, though. We don’t even know if it was an animal. It might have been some kind of algae or it might have been something else. Unlike most small shelly fossils, Cochleatina survived into the Cambrian period.

We’re also not sure why most Ediacaran organisms went extinct at the beginning of the Cambrian, but it’s probable that most were outcompeted by newly evolved animals. There may also have been a change in the chemical makeup of the ocean and atmosphere that caused an extinction event of old forms and allowed the rapid expansion of new animal forms that we call the Cambrian explosion.

We can also learn a lot about what we don’t find in the Ediacaran rocks. Pre-Cambrian animals didn’t appear to burrow into the sea floor, or at least we haven’t found any burrows, just tracks on the surface. Most Ediacaran animals also didn’t have armored bodies or claws or so forth. Researchers think that predation was actually pretty rare back then, with most animals acting as passive filter feeders to gather nutrients from the water, or they ate the microbial mats. It wasn’t until the Cambrian explosion that we see evidence that some animals evolved to kill and eat other animals exclusively.

With every new Ediacaran fossil that’s found and studied, we learn more about this long-ago time when multi-cellular life was brand new.

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 289: Weird Worms



This week we learn about some weird worms!

Further reading:

Otherworldly Worms with Three Sexes Discovered in Mono Lake

Bizarre sea worm with regenerative butts named after Godzilla’s monstrous nemesis

Underground giant glows in the dark but is rarely seen

Giant Gippsland earthworm (you can listen to one gurgling through its burrow here too)

Further watching:

A giant Gippsland earthworm

Glowing earthworms (photo by Milton Cormier):

This sea worm’s head is on the left, its many “butts” on the right [photo from article linked to above]:

A North Auckland worm [photo from article linked to above]:

A giant beach worm:

Show transcript:

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

This week we continue Invertebrate August with a topic I almost saved for monster month in October. Let’s learn about some weird worms!

We’ll start with a newly discovered worm that’s very tiny, and we’ll work our way up to larger worms.

Mono Lake in California is a salty inland lake that probably started forming after a massive volcanic eruption about 760,000 years ago. The eruption left behind a crater called a caldera that slowly filled with water from rain and several creeks. But there’s no outlet from the lake—no river or even stream that carries water from the lake down to the ocean. As a result, the water stays where it is and over the centuries a lot of salts and other minerals have dissolved into the lake from the surrounding rocks. The water is three times as salty as the ocean and very alkaline.

No fish live in the lake, but some extremophiles do. There’s a type of algae that often turns the water bright green, brine shrimp that eat the algae, some unusual flies that dive into the water encased in bubbles, birds that visit the lake and eat the brine shrimp and flies, and eight species of worms that have only been discovered recently. All the worms are weird, but one of them is really weird. It hasn’t been described yet so at the moment is just going by the name Auanema, since the research team thinks it probably belongs in that genus.

Auanema is microscopic and lives throughout the lake, which is unusual because the lake contains high levels of arsenic. You know, a DEADLY POISON. But the arsenic and the salt and the other factors that make the lake inhospitable to most life don’t bother the worms.

Auanema produces offspring that can have one of three sexes: hermaphrodites that can self-fertilize, and males and females that need each other to fertilize eggs. Researchers think that the males and females of the species help maintain genetic diversity while the hermaphrodites are able to colonize new environments, since they don’t need a mate to reproduce.

When some of the worms were brought to the laboratory for further study, they did just fine in normal lab conditions, without extreme levels of arsenic and so forth. That’s unusual, because generally extremophiles are so well adapted for their extreme environments that they can’t live anywhere else. But Auanema is just fine in a non-harsh environment. Not only that, but the team tested other species in the Auanema genus that aren’t extremophiles and discovered that even though they don’t live in water high in arsenic, they tolerate arsenic just as well as the newly discovered species.

The team’s plan is to sequence Auanema’s genome to see if they can determine the genetic factors that confer such high resistance to arsenic.

Next, we go up in size from a teensy worm to another newly discovered worm, this one only about 4 inches long at most, or 10 cm. It’s a marine polychaete worm that lives inside sea sponges, although we don’t know yet if it’s parasitizing the sponge or if it confers some benefit to the sponge that makes this a symbiotic relationship. The worm was only discovered in 2019 near Japan and described in early 2022 as Ramisyllis kingghidorahi.

Almost all worms known are shaped, well, like worms. They have a mouth at one end, an anus at the other, and in between they’re basically just a tube. Ramisyllis is one of only three worms known that have branched bodies, which is why they’re called branching sea worms. In this case, Ramisyllis has a single head, which stays in the sponge, but its other end branches into multiple tail ends that occasionally break off and swim away. The tails are specialized structures called stolons. When a stolon breaks off, it swims away and releases the eggs or sperm it contains into the water before dying. The worm then regenerates another stolon in its place.

Ramisyllis’s branches are asymmetrical and the worms found so far can have dozens of branches. Its close relation, a species that lives in sponges off the coast of northern Australia, can have up to 100 branches. Researchers suspect that there are a lot more species of branching sea worms that haven’t been discovered yet.

Next, let’s head back to land to learn about a regular-sized earthworm. There are quite a few species across three different earthworm families that exhibit a particular trait, found in North and South America, Australia and New Zealand, and parts of Africa. A few species have been introduced to parts of Europe too. What’s the trait that links all these earthworms? THEY CAN GLOW IN THE DARK.

Bioluminescent earthworms don’t glow all the time. Most of the time they’re just regular earthworms of various sizes, depending on the species. But if they feel threatened, they exude a special slime that glows blue or green in the dark, or sometimes yellowish like firefly light. The glow is caused by proteins and enzymes in the slime that react chemically with oxygen.

Researchers think that the light may startle predators or even scare them away, since predators that live and hunt underground tend to avoid light. The glow may also signal to predators that the worm could taste bad or contain toxins. The light usually looks dim to human eyes but to an animal with eyes adapted for very low light, it would appear incredibly bright.

One bioluminescent earthworm is called the New Zealand earthworm. It can grow up to a foot long, or 30 cm, although it’s only about 10 mm thick at most, and while it’s mostly pink, it has a purplish streak along the top of its body (like a racing stripe).

Like other earthworms, the New Zealand earthworm spends most of its time burrowing through the soil to find decaying organic matter, mostly plant material, and it burrows quite deep, over 16 feet deep, or 5 meters. If a person tried to dig a hole that deep, without special materials to keep the hole from collapsing, it would fall in and squish the person. Dirt and sand are really heavy. The earthworm has the same problem, which it solves by exuding mucus from its body that sticks to the dirt and hardens, forming a lining that keeps the burrow from collapsing. This is a different kind of mucus than the bioluminescent kind, and all earthworms do this. Not only does the burrow lining keep the worm safe from being squished by cave-ins, it also contains a toxin that kills bacteria in the soil that could harm the worm.

Worms that burrow as deep as the New Zealand earthworm does are called subsoil worms, as opposed to topsoil worms that live closer to the surface. Topsoil contains a lot more organic material than subsoil, but it’s also easier for surface predators to reach. That’s why topsoil worms tend to move pretty fast compared to subsoil worms.

The New Zealand earthworm glows bright orange-yellow if it feels threatened, so bright that the Maori people used the worm as bait when fishing since it’s basically the best fish lure ever.

Another New Zealand earthworm is called the North Auckland worm, and while it looks like a regular earthworm that’s mostly pink or greenish, it’s also extremely large. Like, at least four and a half feet long, or 1.4 meters, and potentially much longer. It typically lives deep underground in undisturbed forests, so there aren’t usually very many people around on the rare occasion when heavy rain forces it to the surface. Since earthworms of all kinds absorb oxygen through the skin, instead of having lungs or gills, they can’t survive for long in water and have to surface if their burrow completely floods.

We don’t actually know that much about the North Auckland worm. Like the New Zealand earthworm, it’s a subsoil worm that mostly eats dead plant roots. Some people report that it glows bright yellow, although this hasn’t been studied and it’s not clear if this is a defensive reaction like in the New Zealand earthworm. It’s possible that people get large individual New Zealand earthworms confused with smaller North Auckland worm individuals. Then again, there’s no reason why both worms can’t bioluminesce.

An even bigger worm is the giant beach worm. It’s a polychaete worm, not an earthworm, and like other polychaete worms, including the branching sea worm we talked about earlier, it has a segmented body with setae that look a little like legs, although they’re just bristles. The giant beach worm’s setae help it move around through and over the sand. It hides in a burrow it digs in the sand between the high and low tide marks, but it comes out to eat dead fish and other animals, seaweed, and anything else it can find. It has strong jaws and usually will poke its head out of its burrow just far enough to grab a piece of food. It has a really good sense of smell but can’t see at all.

There are two species of giant beach worm that live in parts of Australia, especially the eastern and southeastern coasts, where people dig them up to use as fish bait. The largest species can grow up to 8 feet long, or 2.4 meters, and possibly even longer. There are also two species that live in Central and South America, although we don’t know much about them.

Another huge Australian worm is the endangered Giant Gippsland earthworm that lives in Victoria, Australia. It’s also a subsoil worm and is about 8 inches long, or 20 cm…when it’s first hatched. It can grow almost ten feet long, or 3 meters. It’s mostly bluish-gray but you can tell which end is its head because it’s darker in color, almost purple. It lives beneath grasslands, usually near streams, and is so big that if you happen to be in the right place at the right time on a quiet day and listen closely, you might actually hear one of the giant worms moving around underground. When it moves quickly, its body makes a gurgling sound as it passes through the moist soil in its burrow.

The Giant Gippsland earthworm is increasingly endangered due to habitat loss. It also reproduces slowly and takes as much as five years to reach maturity. Conservationists are working to protect it and its remaining habitat in Gippsland. The city of Korumburra used to have a giant worm festival, but it doesn’t look like that’s been held for a while, which is too bad because there aren’t enough giant worm festivals in the world.

To finish us off, let’s learn what the longest worm ever reliably measured is. It was found on a road in South Africa in 1967 and identified as Microchaetus rappi, or the African giant earthworm. It’s mostly dark greenish-brown in color and it looks like an earthworm, because it is an earthworm. On average, this species typically grows around 6 feet long, or 1.8 meters, which is pretty darn big, but this particular individual was 21 feet long, or 6.7 meters. It’s listed in the Guinness Book of World Records as the longest worm ever measured. Beat that, other worms. I don’t think you can.

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

Thanks for listening!


Episode 288: Mystery Invertebrates



Thanks to Joel for suggesting this week’s topic!

Happy birthday to Fern this week!

Further reading:

Small, rare crayfish thought extinct is rediscovered in cave in Huntsville city limits

Hundreds of three-eyed ‘dinosaur shrimp’ emerge after Arizona monsoon

An invertebrate mystery track in South Africa

The case of the mysterious holes in the sea floor

Contemplating the Con Rit

The Shelton Cave crayfish, rediscovered:

The three-eyed “tadpole shrimp” or “dinosaur shrimp,” triops [photo from article linked above]:

A leech track in South Africa [photo from article linked above]:

A track, or at least a series of holes, discovered in the deep seafloor [photos from article linked above]:

Show transcript:

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

Thanks to Joel who suggested we do an episode about mystery invertebrates! It took me a while, but I think you’re really going to like this episode. Some of the mysteries are solved and some are not, but they’re all fun.

Before we get to the mystery animals, though, we have a birthday shout-out! A great big happy birthday to Fern! I hope you have your favorite type of birthday cake or other treat and get to enjoy it with your loved ones.

Our first mystery starts in a cave near Huntsville, Alabama in the southern United States, which is in North America. Shelta Cave is a relatively small cave system, only about 2,500 feet long, or 760 meters. That’s about half a mile. It’s a nature preserve now but in the early 1900s it was used as an underground dance hall with a bar and everything.

Biologist John Cooper studied the cave’s aquatic ecosystem in the 1960s when he was doing his dissertation work. His wife Martha helped him since they were both active cavers. At the time, the cave ecosystem was incredibly diverse, including three species of crayfish. One was called the Shelta Cave crayfish, which was only a few inches long, or about 5 cm, mostly translucent or white since it didn’t have any pigment in its body, and with long, thin pincers.

It was rarer than the cave’s other two crayfish species, and unlike them it had only ever been found in Shelta Cave. From 1963 to 1975, only 115 individuals had been confirmed in repeated studies of the cave’s ecosystem.

Then, in the 1970s, several things happened that caused a serious decline in the diversity of life in the cave.

The first was development of the land around the cave into subdivisions, which meant that more pesticides were used on lawns and flower beds, which made its way into the groundwater that entered the cave. It also meant more people discovering the cave and going in to explore, which was disturbing a population of gray bats who also lived in the cave. To help the bats and keep people out, the park service put a gate over the entrance, but the initial gate’s design wasn’t a very good one. It kept people out but it also made it harder for the bats to go in and out, and eventually the bats gave up and moved out of the cave completely. This really impacted the cave’s ecosystem, since bats bring a lot of nutrients into a cave with their droppings and the occasional bat who dies and falls to the cave floor.

The gate has since been replaced with a much more bat-friendly one, but studies afterwards showed that a lot of the animals found in the cave had become rare. The Shelta Cave crayfish had disappeared completely. One was spotted in 1988 but after that, nothing, and the biologists studying the cave worried that it had gone extinct.

Then, in 2019, a team of scientists and students surveying life in the cave spotted a little white crayfish with long, thin pincers in the water. The team leader dived down and scooped it up with his net to examine more closely. The crayfish turned out to be a female Shelta Cave crayfish with eggs, which made everyone excited, and after taking a tiny tissue sample for DNA testing, and lots of photographs, they released her back into the water. The following year they found a second Shelta Cave crayfish.

The Shelta Cave crayfish is so little known that we don’t even know what it eats or how it survives in the same environment with two larger crayfish species. Biologist Dr. Matthew Niemiller is continuing Dr. Cooper’s initial studies of the cave and will hopefully be able to learn more about the crayfish and its environment.

Next let’s travel from a cool, damp, flooded cave in Alabama to northern Arizona. Arizona is in the western United States and this particular part of the state has desert-like conditions most of the year. Almost a thousand years ago, people built what is now called Wupatki Pueblo, a 100-room building with a ballcourt out front and a big community room. It was basically a really nice apartment building. Wupatki means “tall house” in the Hopi language, and while the pueblo people who built it are long gone, Wupatki is still an important place for the Hopi and other Native American tribes in the area. It’s also a national monument that has been studied and restored by archaeologists and is open to the public.

In late July 2021, torrential rain fell over the area, so much rain that it pooled into a shallow temporary lake around Wupatki, including flooding the ballcourt. The ballcourt is 105 feet across, or 32 meters, and surrounded by a low wall. One day while the ballcourt was still flooded, a tourist came up to the lead ranger, Lauren Carter. The visitor said there were tadpoles in the ballcourt.

There are toads in the area that live in burrows and only come out during the wet season when there’s rain, and Carter thought the tadpoles might be from the toads. She went to investigate, saw what looked like tadpoles swimming around, and scooped one up in her hands to take a closer look. But the tadpoles were definitely not larval toads. In fact, they kind of looked like teensy horseshoe crabs, with a rounded shield over the front of the body and a segmented abdomen and tail sticking out from behind, with two long, thin spines at the very end that are called caudal extensions. It had two pairs of antennae and lots of small legs underneath, some adapted for swimming. The largest of the creatures were about two inches long, or 5 cm.

What on earth were they, and where did they come from? This area is basically a desert. Carter stared at the weird little things and remembered hearing about something similar when she worked at the Petrified Forest National Park, also in Arizona. She looked the animal up and discovered what it was.

It’s called Triops and is in the order Notostraca. Notostracans are small crustaceans shaped sort of like tadpoles, which is why it’s sometimes called the tadpole shrimp, but it’s not a shrimp. It has two eyes on the top of its head visible through its flattened, smooth carapace. Species in the genus Triops also have a so-called third eye between the two ordinary eyes, although it’s a very simple eye that probably only detects light and dark. Many crustaceans have these third eyes in their larval forms but very few retain them into adulthood.

Notostracans have been around for about 365 million years, and haven’t changed much in the last 250 million years. It’s an omnivore that mostly lives on the bottom of freshwater pools and shallow lakes, often temporary ones like the flooded ballcourt, although some species live in brackish water and saline pools, or permanent waterways like peat bogs.

Triops eggs are able to tolerate high temperatures and dry conditions, with the eggs remaining viable for years or even decades in the sediment of dried-up ponds. When enough water collects, the eggs hatch and within 24 hours are miniature versions of the adult Triops. They grow up quickly, lay lots of eggs, and die within a few months or when the water dries up again.

Triops eggs are even sold as aquarium pets, since they’re so unusual looking and are easy to care for. They basically eat anything. They especially like mosquito larvae, so if you see some in your local pond or other waterway, give them a tiny high-five.

In 1996, some workers near Indianapolis, Indiana were servicing a tank full of chemical byproducts from making plastic auto parts when they noticed movement in the toxic goo. They investigated and saw several squid-like creatures swimming around. They were red-brown and about 8 inches long, or 20 cm, including their arms or tentacles, but were only about an inch wide, or 2.5 cm.

The workers managed to capture one and put it in a jar, which they stuck in the break room refrigerator. By the time someone in management arranged to have it examined by a scientist, the jar had been thrown out. If you’ve ever tried to keep food in a break room fridge, you’ll know that there’s always someone who will throw out everything in the fridge that isn’t theirs, no matter whether it’s labeled or brand new or not. I have had my day’s lunch thrown out that had only been in the fridge a few hours. Anyway, when the tank was cleaned out the following year, no one found any creatures in it at all.

This sounds really interesting, but there’s precious little information to go on. The story appeared in a few newspapers but we have no names of the people who reportedly saw the creatures, no follow-up information. It has all the hallmarks of a hoax or urban legend. The creatures’ size also seems quite large for extremophiles in a small, closed environment. What would they find to eat to get so big?

Next let’s talk about some mysterious tracks made by invertebrates, as far as we know. We’ll start with a track on land that was a mystery at first, but was solved. A man in the Kruger National Park in South Africa named Rudi Hulshof came across a weird track in the sandy dirt that he didn’t recognize. It was maybe 10 mm wide and kind of looked like a series of connected rectangles, as though a tiny person was moving a tiny cardboard box by rolling it over and over, but there weren’t any footprints, just the body track.

Curious, Hulshof followed the track to find what had made it, and finally discovered the culprit. It was a leech! Most leeches live in water, whether it’s the ocean, a pond or swamp, a river, or just flooded ground. Most species are parasitic worms that attach to other animals with suckers, then pierce the animal’s skin and suck its blood. The leech stays on the animal until it’s full, then drops off. Some leeches are terrestrial, but it appears that this one was a freshwater leech that had attached to an animal passing through the water, then dropped off onto land. It had crawled as far as it could trying to find a better environment, but when Hulshof found it it was dead, so it had not had a good day.

The leech moves on land by stretching the front of its body forward, then dragging its tail end up in a bunch kind of like a worm (it is a kind of worm), so that’s why its track was so unusual-looking. It’s a good thing Hulshof found the leech before something ate it, or else he’d probably still be wondering what had made that track.

We have photographs of other tracks that are still mysterious. You may have heard about one that’s been in the news lately. This one was found by a deep-sea rover in July 2022, more than a mile and a half deep, or 2500 meters, in the north Atlantic Ocean.

The track may or may not actually be a track, although it looks like one at first glance. It consists of a line of little holes in the seafloor, one after the other, although they’re not all the same distance apart. The rover saw them on two separate dives in different locations, so it wasn’t just one track, but although the scientists operating the rover remotely tried to look into the holes, they couldn’t get a good enough view. It does look like there’s sediment piled up next to the holes, so researchers think something might actually be digging the holes, either digging down from the surface to find food hidden in the sediment, or digging up from inside the sediment to find food in the water. The rover did manage to get a sample of sediment from next to one of the holes and a water sample from just above it, and eventually those samples will be tested for possible environmental DNA that might help solve the mystery.

This wasn’t the first time these holes have been seen in the area, though. An expedition in 2004 saw them and hypothesized that the holes are made by an invertebrate with a feeding appendage of some kind that it uses to dig for food. Not only that, we have similar-looking fossil holes in rocks formed from deep marine sediments millions of years ago.

Other deep-sea tracks have a known cause, and humans are responsible. In the 1970s and 1980s, ships with deep-sea dredging equipment traveled through parts of the Pacific Ocean, testing the ocean floor to see whether the minerals in and beneath the sediment were valuable for mining. A few years ago scientists revisited the same areas to see how the ecosystems impacted by test mining had responded.

The answer is, not well. Even after 40 years or so since the deep-sea mining equipment sampled the sea floor, the marks remain. The deep sea is a fragile ecosystem to start with, and any disturbance takes a long, long time to recover—possibly thousands of years. So while the holes discovered in 2022 were almost certainly made by an animal or animals, they might be quite old.

Let’s finish with a mystery animal we’ve talked about before, but a really long time ago—way back in episode 6. It’s definitely time to revisit it.

In 1883 when he was 18 years old, a Vietnamese man named Tran Van Con had seen the body of an enormous creature washed up on shore at Hongay in Vietnam. Van Con said it was probably 60 feet long, or 18 meters, but less than three wide wide, or 90 cm. It had dark brown plates on its back with long spines sticking out from them to either side, and the segment at its tail end had two more spines pointing straight back. It didn’t have a head, which had presumably already rotted off, or something bit it off before the animal washed ashore. It had been dead for a long time considering the smell. In fact, it smelled so terrible that locals finally towed it out to sea to get rid of it. It sank and that was the last anyone ever saw of it. The locals referred to it as a con rit, which means “millipede,” since the armor plates made it look like the segmented body of an immense millipede.

Lots of people have made suggestions as to what the con rit could be, but nothing really fits. It was the length of a whale, but it doesn’t sound like any kind of whale known. The armored plates supposedly rang like metal when hit with a stick. Even if this was an exaggeration, it probably meant the armor plates were really hard, not just the skin of a dead whale that had hardened in the sun. It also implies that the plates had empty space under them, allowing them to echo when hit. Zoologist Dr. Karl Shuker suggests that the plates might have been the exoskeleton of a crustacean of some kind, which makes a lot more sense than a whale, but the sheer size of the carcass is far larger than any crustacean, or even any arthropod, ever known.

There’s also some doubt that the story is accurate. It might even be a hoax. We only know about the con rit at all because the director of Indochina’s Oceanographic and Fisheries service, Dr. A. Krempf, talked to Tran Van Con about it in 1921. That was 38 years after Van Con said he saw the creature, so he might have misremembered details. Not only that, Krempf translated the story from Vietnamese, and there’s no way of knowing how accurate his translation was.

The con rit is also a monster from Vietnamese folktales, a sort of sea serpent that had lots of feet. It was supposed to attack fishing boats to eat the sailors, until a king caught it and chopped it up into pieces. A local mountain was supposedly formed from its head, and the other pieces of its body turned into the unusual stones found on a nearby island.

There’s always the possibility that Tran Van Con actually told Krempf this folktale, but that Krempf misunderstood and thought he was telling him something he actually witnessed. Then again, there are eight reports from ships in the area between 1893 and 1915 of creatures that might have been a con rit. One account from 1899 was a sighting of a creature estimated as being 135 feet long, or 41 meters, which was rowing itself along at the surface by means of multiple fins along its sides.

Whatever the con rit was, there haven’t been any sightings since 1915. That doesn’t mean there isn’t a population of incredibly long invertebrates living in the deep ocean in southeast Asia. If it does exist, maybe one day a deep-sea rover will spot one. Maybe it dug those little holes, who knows?

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 282: Little Longtailed Birds



Sign up for our mailing list!

Thanks to Elaine for suggesting one of our long-tailed birds this week!

Happy birthday to Jasper!! Have a great birthday!

Further reading:

Fossil of Ancient Long-Tailed Bird Found in China

All adult scissor-tailed flycatchers have long tails:

The long-tailed sylph male is the one with the long tail:

The long-tailed widowbird male has a long tail:

The long-tailed widowbird female has a short tail:

The pin-tailed whydah male has a long tail:

A pin-tailed whydah baby (left) next to a common waxbill baby (right):

Kompsornis longicaudus had a really long tail:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week is a short episode all about little birds with really long tails. The tails are longer than the episode. Thanks to Elaine for suggesting one of the birds we talk about today!

But before we start learning about birds, we have a birthday shout-out! Happy birthday to Jasper, who has the best name and who will hopefully have the best birthday to go along with it!

Let’s start with Elaine’s suggestion, the scissor-tailed flycatcher. I’m embarrassed to admit that Elaine suggested this bird way back in 2020, so it’s about time we talked about it.

The scissor-tailed flycatcher lives in south-central North America during the summer, especially Texas and Oklahoma, and migrates to parts of Mexico and Central America in winter. It’s pale gray with black and white wings and tail, and salmon pink markings on its sides and under its wings. It also has a really long tail. It gets the name scissor-tail because its tail is so long and forked that it’s sort of the shape of an open pair of scissors. The male’s tail is typically longer than the female’s, longer than the rest of its body. The bird is about the size of an average songbird, with a body length of about 5 inches, or 13 centimeters, but with a tail that can increase its overall length to over 14 inches, or 36 cm.

The scissor-tailed flycatcher prefers open areas like pastures and fields, where there’s lots of space but some brush, trees, or fences nearby to perch in. It mostly eats insects, but it will also eat berries, especially in winter. It’s related to kingbirds and pewees and will even hybridize with the western kingbird where their ranges overlap. Its long tail is partly for display, but mostly it helps the bird maneuver in midair as it chases insects, or hover in midair as it looks around for an insect to catch. It especially likes grasshoppers, and when it catches one, it will usually kill it before eating it by smashing it against a tree limb or other perch.

Another little bird with a long tail is the long-tailed sylph, which is a type of hummingbird! It lives on the eastern slopes of the Andes Mountains in northwestern South America, mostly along forest edges, in gardens, grasslands, and other mostly open areas. It migrates to different parts of the mountains at different times of year to follow the flowering of its favorite plants. It’s larger than many species of hummingbird even if you don’t count the tail.

It eats nectar like other hummingbirds do, but also eats tiny insects and spiders. Its bill is black and not very long compared to most of its relations. Sometimes it will jab the tip of its bill straight through the base of a flower to get at the nectar, instead of inserting it into the flower like other hummingbirds do, and while it can hover, sometimes it perches to feed instead.

Both the male and female long-tailed sylph are a beautiful metallic blue and green in color, although the male is brighter and has purplish-brown wings. The female is about 4 inches long, or 10 cm, including her tail, and while the male is about the same size as the female, his tail is really long—up to 4.5 inches long, or 12 cm. His tail is forked like the scissor-tailed flycatcher’s, but unlike the flycatcher, the sylph’s tail makes it harder for the bird to fly. During breeding season the male attracts a mate by flying in a U-shaped pattern that shows off his tail and his flying ability.

The male long-tailed widowbird also attracts a mate with a flying display to show off his long tail. It lives in grasslands in a few parts of Africa, with the biggest population in South Africa. It forages in small flocks looking for seeds, and it also eats the occasional insect or spider. It’s a sparrow-like bird only about 4 inches long, or 10 cm, not counting its tail. The female is mostly brown with darker streaks and has a short tail. The male is black with red and white patches on the shoulders of his wings, called epaulets. His coloring, including the epaulets, is almost identical to that of a totally unrelated bird, the red-winged blackbird of North America, but he has something the blackbird doesn’t: a gigantically long tail.

The male widowbird’s tail is made up of twelve feathers, and about half of them grow up to 20 inches long. That’s nearly two feet long, or half a meter. Like the long-tailed sylph, the long-tailed widowbird’s tail actually makes it harder for him to fly. If it’s raining, he can’t fly at all. Fortunately for him, outside of the breeding season his tail is much shorter. During display flights, he spreads his tail feathers to show them off better and flies very slowly. Males with the longest tails attract the most females.

Similarly, the pin-tailed whydah is another little sparrow-like bird where the male grows a really long tail to attract females. It lives in grasslands, savannas, and open woodlands in sub-Saharan Africa, which just means south of the Sahara Desert. It mostly eats seeds.

During breeding season, the male is a striking pattern of black and white with a bright orangey-red bill and really long tail plumes. He’s about the size of the long-tailed widowbird but his tail grows about 8 inches long, or 20 cm. The female is brown with darker streaks and looks a lot like a sparrow, although it’s not related to sparrows. To impress a female, the pin-tailed whydah will hover in place near her, showing off his long tail plumes and his flying ability.

A lot of whydah species grow long tails. A lot of whydahs are also brood parasites, including this one, meaning that instead of building a nest and taking care of her own eggs, the female sneaks in and lays her eggs in the nest of a different species of bird. Then she flies away, probably whistling to make her seem extra nonchalant, and leaves the other bird to take care of her eggs and the babies when they hatch. She mostly lays her eggs in the nests of various species of finch, and not only do her eggs resemble the finch’s eggs except that they’re bigger, the babies resemble finch babies when they hatch, except they’re bigger.

Specifically, the babies have a really specific gape pattern. When an adult bird approaches its nest, a baby bird will gape its mouth wide to beg for food. This prompts the parent bird to shove some food down into that mouth. The more likely a baby is to be noticed by its parent, the more likely it is to get extra food, so natural selection favors babies with striking patterns and bright colors inside their mouths. Many finches, especially ones called waxbills, have a specific pattern of black and white dots in their mouths that pretty much acts as a food runway. Insert food here. The whydah’s mouth gape pattern mimics the waxbill’s almost exactly. But as I said, the whydah chick is bigger, which means it can push the finch babies out of the way and end up with more food.

The pin-tailed whydah is a common bird and easily tamed, so people sometimes keep it as a pet. This is a problem when it’s brought to places where it isn’t a native bird, because it sometimes escapes or is set free by its owners. If enough of the birds are released in one area, they can become invasive species. This has happened with the pin-tailed whydah in many parts of the world, including parts of Portugal, Singapore, Puerto Rico, and most recently southern California. Since they’re brood parasites, they can negatively impact a lot of other bird species in a very short time. But a study released in 2020 about the California population found that they mostly parasitize the nests of a bird called the scaly-breasted munia, a species of waxbill from southern Asia that’s been introduced to other places, including southern California, where it’s also an invasive species. So I guess it could be worse.

There are lots of other birds with long tails we could talk about, way too many to fit into one episode, but let’s finish with an extinct bird, since that seems to be the theme lately. In May 2020, an ancient bird was described as Kompsornis longicaudus, and it lived 120 million years ago in what is now China. Its name means long-tailed elegant bird. It was bigger than the other birds we’ve talked about today, a little over two feet long, or 70 cm, but a lot of that length was tail.

Kompsornis is only known from a single fossil, but that fossil is amazing. Not only is it almost a complete skeleton, it’s articulated, meaning it was preserved with all the body parts together as they were in life, instead of the bones being jumbled up. That means we know a lot about it, including the fact that unlike other birds of the time, it didn’t appear to have any teeth. It also shows other features seen in modern birds but not always found in ancient birds, including a pronounced keel, which is where wing muscles attach. That indicates it was probably a strong flier. It also had a really long tail, but unlike modern birds its tail was bony like a lizard’s tail although it was covered with feathers.

During their study of Kompsornis, the research team compared it to other birds in the order Jeholornithiformes, which seem to be its closest relations. There were six species known, with Kompsornis making a seventh—except that during the study, the team discovered that one species was a fake! Dalianraptor was also only known from one fossil, and that fossil was of a different bird with the arms of a flightless theropod added in place of its missing wings. Send that fossil to fossil jail!

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

Thanks for listening!


Episode 276: Hominins and Art



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

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

Further listening:

Humans Part One

Further reading:

Were Neanderthals the Earliest Cave Artists?

Neanderthals Built Mysterious Stone Circles

DNA reveals first look at enigmatic human relative

What does it mean to have Neanderthal or Denisovan DNA?

Hand and footprint art dates to mid-Ice Age

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

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

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

Some cave paintings probably made by Neandertals:

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Thanks for listening!


Episode 265: Penguins!



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

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

Further reading:

March of the penguins (in Norway)

Rare Yellow Penguin Bewilders Scientists

Giant Waikato penguin: school kids discover new species

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

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Thanks for listening!


Episode 263: Pair Bonds



Sign up for our mailing list! We also have t-shirts and mugs with our logo!

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

Further reading:

Wisdom the albatross, now 70, hatches yet another chick

The prairie vole mates for life:

Swans mate for life:

The black vulture also mates for life:

The Laysan albatross:

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

Dik-diks!

The dik-dik nose is somewhat prehensile:

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

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

[gibbons singing]

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

Thanks for listening!