Category Archives: Antarctica

Episode 359: The Antarctic Death Star(fish)!

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Thanks to Morgan for suggesting this week’s topic, the Antarctic Death Star!

Further reading:

Giant Monster Starfish ALERT

Echinoderm Tube Feet Don’t Suck! They Stick!

Bodies of Starfish and Other Echinoderms Are Really Just Heads, New Research Suggests

The Antarctic death star [from first link listed above]:

The “beartrap” structures, magnified [from first link listed above]:

Show transcript:

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

It’s been way too long since we talked about an invertebrate, so this week we’ll look at one suggested by Morgan, the Antarctic death star.

It has a lot of other names too, including the Antarctic sun starfish and the wolftrap or beartrap starfish. Its scientific name is Labidiaster annulatus. I’m going to call it the death star because I think that’s hilarious.

As you may have guessed from its common names, the Antarctic death star is a starfish that lives in cold ocean waters near the Antarctic, AKA the south pole. But its common names also hint at how it gets its food, and this would be a good time to take a moment and be glad you’re not a copepod that also lives in the Antarctic Ocean.

The death star is reddish-brown on its dorsal side, white underneath. It’s a large starfish, up to two feet across, or 60 cm, and it also has a lot of legs, more properly called rays—up to 50 of them. The rays are long, narrow, and very flexible, and the undersides have rows of little structures called tube feet. All echinoderms, including starfish, have these tube feet and they’re used for several purposes. One important purpose is helping the animal stick to a hard surface, which allows it to climb around more easily and right itself if it gets flipped over.

For over 150 years scientists thought the tube feet acted like little suction cups, but that didn’t explain how a starfish or other echinoderm could stick to porous surfaces. It wasn’t until 2012 that a study was published explaining how the tube feet actually work. The tube feet exude tiny amounts of a sticky chemical that acts like glue.

The death star’s body also has little spines and bumps all over it, but it also has some structures that give the animal its other names, the wolftrap or beartrap starfish. The structures are called pedicellariae [PED-uh-suh-LAIR-ee-aye], which are also common in echinoderms. Most echinoderms seem to use them to keep algae and other organisms from settling on the body, although scientists aren’t completely sure. Pedicellariae have muscles and sensory receptors, and when something touches them, they snap shut like a trap. In the case of the Antarctic death star, its pedicellariae are extra big and really sharp. When a krill or other tiny animal brushes against one of these little traps, it grabs the animal and then the death star can eat it.

But that’s just part of what’s going on when the death star goes hunting, so let’s discuss it in more detail.

Most starfish spend almost all their time on the ocean floor, walking around looking for food. The death star does this too, but not all the time. Quite often a death star will climb on top of a rock or other large structure, and then it will extend some of its rays up and out into the water. It waves its rays around and if it touches a small animal, it will wrap the rays around it. The pedicellariae also snap shut. Then the death star can eat whatever it caught. Usually this is krill or amphipods, but it’s not a picky eater. Since it will eat animals it finds already dead, researchers aren’t completely sure if the death star ever catches fish. They’ve certainly found dead fish in death star stomachs, but the water it lives in is so cold that not many fish live there anyway. Fish don’t make up a big part of the death star’s diet, whether or not it’s catching them itself. The death star also eats other starfish, including smaller death stars.

Like other starfish, the death star can eat surprisingly large pieces of food because it can evert its stomach. This means it can actually push its stomach out through its mouth and engulf whatever large food it’s found or caught. The digestion process starts right away, which allows the starfish to eat food that can’t actually fit through its mouth. It doesn’t chew its food because it doesn’t have any kind of teeth or jaws, but who needs teeth and jaws if your stomach can just reach out and grab food?

While I was researching the death star, I came across a study published in November 2023 about echinoderms, so let’s learn something surprising about starfish and their relations in general.

Echinoderms demonstrate radial symmetry instead of bilateral symmetry. That’s why you can’t tell when a starfish or other echinoderm is facing forward, because it doesn’t actually have a forward. But it’s actually more complicated than it sounds, because the distant ancestor of echinoderms, which lived during the Cambrian almost half a billion years ago, did demonstrate bilateral symmetry, and the larvae of modern echinoderms do too. When a modern echinoderm larva develops into an adult, the left side of its body is the only part that grows. The right side of its body is absorbed and from then on the body develops radially. It actually shows pentaradial symmetry, with five sections around the central part of the body. That’s why so many starfish have five rays, although obviously not all of them. The death star starts out with five rays but adds more and more as it grows.

For a long time scientists have wondered if echinoderms technically have heads or if they’re just bodies. They don’t have eyes or nostrils or most other body parts that we associate with the head, just an oral opening in the middle of the underside of the disc. Starfish do have cells at the ends of their rays that act as eyespots, which are sensitive to light and dark but can’t actually see anything else. Instead of a brain, it has a nerve ring around its mouth and connected nerve nets in its rays, and its digestive system extends into its rays.

In other words, it sure seems like an echinoderm has no head and is basically just a weird body. But the new study came to a surprising conclusion. The study examined starfish genetics and discovered that the genes associated with head development were there. It was the genes associated with the development of a body and tail that were missing. In other words, the starfish, and echinoderms in general, are just really complicated heads.

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

Thanks for listening!

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

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

Thanks to Simon and Anbo for sending in some corrections!

Further reading:

Lessons on transparency from the glass frog

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

Rare wild asses spotted near China-Mongolia border

Aye-Ayes Use Their Elongated Fingers to Pick Their Nose

Homo sapiens likely arose from multiple closely related populations

Scientists Find Earliest Evidence of Hominins Cooking with Fire

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

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

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

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

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

The Mongolian wild ass:

The giant barb fish [photo from this site]:

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

Show transcript:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Thanks for listening!

Episode 265: Penguins!

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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 249: Strange Seals

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Thanks to Richard from NC for his suggestion that leads us to learn about some interesting seals!

Further reading:

Mystery of Siberian freshwater seal food choice solved

Under Antarctica’s ice, Weddell seals produce ultrasonic vocalizations

Further listening/watching:

Rarely-heard Weddell Seal Sounds in Antarctica

The bearded seal Wikipedia page with audio so you can listen over and over and over

The Baikal seal, the world’s only fully fresh water seal species:

Baikal seal, round boi:

The Baikal seal’s teeth have teeth:

A Weddell seal mama with her pup who seems to be practicing singing:

Look ma, no ears!

The bearded seal. Can you tell where its name comes from? (Moustachioed seal might be more accurate.) (Also, note the ear opening with no external ear flap.)

Show transcript:

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

This week let’s learn about some interesting seals. Thanks to Richard from NC who suggested freshwater seals, which is where we’ll start.

Most seals live on the coast and spend most of the time in the ocean. But there’s one species of seal that lives exclusively in fresh water. That’s the Baikal [bay-CALL] seal, and the only place it lives is a big lake in Siberia called Lake Baikal.

Lake Baikal formed where two sections of the earth’s crust are being pulled apart by continental drift. That’s called a rift lake or rift valley lake. The lake gets bigger every year, but only by a tiny amount—just under an inch, or 2 cm. Since this has been going on for an estimated 25 to 30 million years, though, it’s an extremely big, deep lake. It is, in fact, the deepest lake on earth, and is also the oldest lake on earth. It’s more than twice as old as Lake Tanganyika in East Africa, which is also a large, deep rift lake but only about 12 million years old at the most.

Lake Baikal is almost 400 miles long, or 636 km, and nearly 50 miles wide, or 80 km. At its deepest point, it’s 3,893 feet deep, or 1,186.5 meters. That’s from the surface of the water to the muddy bottom. But that mud and sediment on the bottom has been building up for a very long time and there’s a lot of it—4.3 miles of it, in fact, or 7 km. The water is very clear and very oxygenated, but the surface freezes for several months out of the year. Then again, there are some hydrothermal vents, especially in the deepest areas, that heat the water around them to 122 degrees Fahrenheit, or 50 Celsius.

Because Lake Baikal is so deep, so big, so oxygenated, and so old, lots of species of animal live in and around it that live nowhere else in the world. That includes the Baikal seal.

The Baikal seal is related to the Arctic ringed seal but has lived in the lake exclusively for probably two million years. It only grows five and a half feet long at most, or 1.65 meters, and is usually closer to four feet long, or 1.2 meters. It’s gray in color and has no external ears, so that its head appears smooth. It can still hear, but because it doesn’t have ears sticking out of its head, it’s more streamlined than seals with external ears. It has large eyes, a pair of front flippers that it uses to maneuver in the water and on land, and a pair of hind flippers that act like a tail instead of legs.

That’s actually the main difference between earless and eared seals. Earless seals are more streamlined in general and more adapted for life in the water and for deep diving, but they’re awkward on land because they can’t use their hind limbs for walking. Eared seals have little flaps of external ears and while their hind flippers act as a tail in the water, the seal can turn its hind flippers over to walk on them on land.

The Baikal seal is quite small for a seal, which keeps it from needing as much food as a bigger animal. For a long time people thought the Baikal seal mostly ate fish, but a study published in late 2020 determined that it eats a whole lot of amphipods. Lake Baikal is home to a species of amphipod that grows up to about 10 millimeters long. Amphipods are a type of crustacean and all other freshwater amphipods known are bottom-dwellers. Only the Lake Baikal amphipod is free-floating.

The seal catches these tiny amphipods by sucking them up in a big mouthful of water, closing its teeth tightly, and using its tongue to force the water out through its teeth. The amphipods get caught against the teeth and the seal swallows them, yum. This is a type of filter feeding used by some other species of seal too, including the crabeater seal. Like the crabeater seal, it’s so well adapted to filter feeding that it has specialized teeth with curved projections all around their edges. These projections interlock closely when the seal closes its mouth. Because it doesn’t have to depend on eating fish, the Baikal seal isn’t threatened by commercial fishing. As long as it has plenty of amphipods to eat, it’s happy.

While the Baikal seal is the only truly freshwater seal species, a subspecies of ringed seal lives in a lake in Finland. Unlike the Baikal seal, though, which are numerous and doing just fine, the Saimaa ringed seal is endangered, with only around 400 individuals left in the wild. They’re strictly protected these days, fortunately, and the population is growing after it reached a low of only about 100 animals in 1983.

During the Pleistocene, the land mass that is now Finland was pressed down by the weight of glaciers. Once the glaciers melted, the land began to slowly rise back up until the lake where a population of ringed seals lived was cut off from the ocean.

Some other seals live in lakes that are cut off from the sea, including a population of harbor seals in Iliamna Lake in Alaska and a subspecies of harbor seal in northern Quebec, Canada, but let’s move on to seals that live in the ocean instead of fresh water.

Specifically, let’s discuss two earless seals that make interesting sounds. You may think you know what a typical seal sounds like, such as this kind of barking call:

[barking sound]

That’s actually not a seal but a closely related pinniped called a sea lion. Even though it’s not a seal, it is sort of technically a seal because it shares a family with fur seals and walruses, Otariidae, also called the eared seals that we talked about earlier. Some seals bark like sea lions and make lots of other noises, but it’s the earless seals that can really make weird sounds.

For instance, listen to this eerie sound:

[Weddell seal call]

That’s not a whale, it’s a seal. The Weddell seal lives around Antarctica and can grow quite large, up to 11 ½ feet long, or 3.5 meters. Males and females look alike although females tend to be slightly larger. It eats fish, squid, crustaceans, and pretty much anything else it can catch. It dives deeply and can stay underwater for up to 80 minutes, and while it has good eyesight, it doesn’t need to see to find food. The whiskers on its snout are incredibly sensitive and can sense tiny movements of water that indicate exactly where a fish or other animal is swimming.

Both male and female Weddell seals make various vocalizations, including some that can be described as songs, although the songs seem to be rare and researchers aren’t sure what the seals communicate with them. There’s still a lot we don’t know about these seals. Because Antarctica is so far away from most human activity, it’s extremely quiet most of the time. The seals can hear each other without having to compete with the noise from cars and boats and things like that. A seal sitting on the ice can hear other seals calling from deep in the water below the ice, and in fact the ice can amplify the sounds so well that scientists living in the Antarctic report being able to feel the sounds as well as hear them.

Here’s another clip of Weddell seals. These sounds are taken from an amazing youtube video I’ve linked to in the show notes. It’s short and has two scientists talking a little bit about their experiences hearing the seals, and then there’s about a minute of seal calls afterwards.

[Weddell seals calling]

Another seal with a loud, amazing vocalization is the bearded seal. It lives on the other side of the world from the Weddell seal, in the Arctic Ocean, and can grow almost nine feet long, or 2.7 meters. It eats fish and squid but mostly eats animals that live on the sea floor, including clams, polychaete worms, sea anemones, and many others. Like the Weddell seal and many other seals, its whiskers are incredibly sensitive. The bearded seal uses its long whiskers to feel around in the soft mud at the bottom of the ocean, looking for food.

In the spring, male bearded seals sing loudly and rhythmically, either to attract a mate or to defend a territory, or maybe both or something else—we don’t know. This is what the bearded seal sounds like underwater. I grabbed this audio off Wikipedia if you need to listen to it on repeat for a very long time. It’s an incredible sound.

[bearded seals singing]

This is what a bunch of bearded seals sound like when they’re singing together. This audio was taken on land although the seals sing underwater.

[more bearded seals singing]

These vocalizations sound so much like whale calls that I wondered if some seals can echolocate the way whales and dolphins can. There are quite a few studies into this topic, but right now most of the evidence points to no, seals don’t use echolocation to navigate underwater. Of course, studies in the future might discover something new about potential echolocation in seals. It’s only been very recently that sophisticated studies on bats have discovered that many species use different types of echolocation.

Conclusions of a two-year study published at the very end of 2020 show that a lot of Weddell seal vocalizations are ultrasonic, meaning they’re much higher than humans can hear. While the study doesn’t show any evidence of echolocation, they weren’t actually looking for it either. So you never know.

It’s possible, of course, that even if seals don’t echolocate right now, they might one day evolve the ability. Earless seals are well adapted to the water but still spend part of the time on ice or on land, especially to give birth. Many millions of years from now, the descendants of today’s seals might be completely aquatic the way whales and dolphins are. Because most scientists today think that seals can’t echolocate because their ears need to be useful on land as well in water, a fully aquatic seal that doesn’t need to hear well in the air might then develop echolocation to help it navigate underwater.

I’ll do a follow-up episode about seals and echolocation in a few million years when we can determine whether that’s happening.

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

Thanks for listening!

Episode 238: The Pink Fairy Armadillo and Two Adorable Friends

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This week we’ve got three adorable little animals to learn about! Thanks to Simon and Thia, Elaine, and Henry for their suggestions!

Further reading:

Turning the spotlight on the rusty-spotted cat (Wildlife SOS)

The cute and fuzzy pink fairy armadillo:

The cute and fuzzy rusty spotted cat:

The cute and fuzzy baby Arctic tern:

Adult Arctic terns:

Show transcript:

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

This week we’ve got three strange and adorable animals for you, all listener suggestions because I’m getting really behind on those. Thanks this week to Simon and Thia, Elaine, and Henry!

First, Simon and Thia suggested the pink fairy armadillo. That’s one we covered briefly in a Patreon episode back in 2018, but it deserves to be featured in the main feed because it’s so strange and cute. It lives in deserts and grasslands of central Argentina, South America, but since its range is so restricted and it spends most of its life underground and is rarely seen by humans, we don’t know much about it.

The pink fairy armadillo is the smallest armadillo species known. It only grows about 4.5 inches long, or 11.5 cm, small enough to sit in the palm of your hand. It’s protected by a leathery shell that runs from its nose along the top of its head and down its back to its bottom, and the shell is segmented like a regular armadillo’s shell except that it’s a delicate pink. The fluffy fur on the animal’s sides and tummy is white. It has a short spade-shaped tail, but the rear of its body is flattened, and it uses its flat bottom to compress dirt in the tunnels as it digs. It has a small head, short legs, and gigantic front claws. Its hind claws are big too.

It spends almost all of its life underground, digging shallow tunnels and eating small animals like worms, insect larvae, snails, and insects like ants, which it probably hunts by scent. It has a good sense of smell but its eyes are tiny and its ears don’t show at all, although it does have good hearing. It can dig extremely quickly. It loosens the soil with its huge front claws, kicks it back with its hind claws, and then does a quick reverse to tamp the new dirt heap into a firm column with its flat bottom. This keeps the floor of its burrow clear so the armadillo can breathe properly and helps keep the burrow from collapsing.

Almost the only time the pink fairy armadillo surfaces is when it reaches an obstacle it can’t dig through or around, and then its claws are so big it has trouble walking on hard surfaces. This is bad if it tries to cross a road. Most sightings of pink fairy armadillos are of roadkill animals. Sometimes it surfaces after heavy rain when its burrows are flooded.

The reason the pink fairy armadillo’s shell is pink is that blood vessels show through it. Researchers think it can regulate its temperature according to how much blood flows through the vessels beneath the shell. The shell is only attached to the body by a membrane along the spinal column and doesn’t protect it as well as other armadillo shells do, but then it’s almost always underground so the shell probably mostly protects it from rocks and roots.

The pink fairy armadillo doesn’t do well in captivity, usually dying from stress within a day or two of capture, and since it’s almost always underground it can be hard to find and study. It’s threatened by habitat loss, climate change, poaching, and the use of pesticides. It’s extremely sensitive to changes in temperature and soil.

The pink fairy armadillo has a similar-looking but slightly larger relative, the greater fairy armadillo, which can grow up to 7 inches long, or 17.5 cm. It’s also a burrowing armadillo that lives in South America, which has an additional conservation problem. It’s considered by locals to be the spirit of a dead baby, so if a local sees it they usually kill it.

Next, Elaine suggested the rusty spotted cat. It’s a tiny cat that lives in forests and grasslands in South Asia, especially in India and Sri Lanka, and although it resembles a tiny domestic cat, it’s not all that closely related to domestic cats or their wild cousins.

The rusty spotted cat is reddish-gray with darker stripes on the face and small rusty-red spots over most of its body. It’s about half the size of a domestic cat and grows up to 19 inches long at most, or 48 cm, not counting its tail, which adds another 12 inches or so to its length, or 30 cm. This is where I tried to measure my cats with the soft plastic tape measure I use for sewing, but they thought it was a toy so I never did figure out how long they are. Also, my tape measure has holes in it now from claws and teeth. The rusty spotted cat only weighs up to about 4 pounds, or 1.8 kg. Keep in mind that these numbers are for the biggest possible rusty spotted cats. Most are much smaller. They’re basically kitten-sized.

The rusty spotted cat is mostly nocturnal and eats small animals like mice and other rodents, birds, lizards, and insects. It mostly hunts on the ground and mostly only climbs trees to escape predators. It’s a fierce hunter and can be very aggressive despite its small size, so even though it’s really cute and some people want to keep it as a pet, it’s very wild and not friendly. You’re way better off adopting a small domestic cat. Besides, the rusty spotted cat is endangered in the wild due to habitat loss and hunting for its fur, so we shouldn’t be keeping it as pets.

Conservationists are working to protect the rusty spotted cat by educating people who live in the area about what the cat is. While a mother rusty spotted cat is out hunting, she leaves her kittens in a little nest in long grass. If she makes her nest in a cultivated field, like a tea plantation, sometimes a worker harvesting or caring for the plants will find the kittens. People are basically good at heart and want to help baby animals, so a lot of times the worker will take the kittens home thinking they’re abandoned. A conservation group called Wildlife SOS is working to teach people to leave the babies alone, and when they hear about someone who’s found a kitten, they send someone out to learn where the kitten was found and when, and will reunite the kittens with their mother. Wildlife SOS also helps other animals in India, including leopards and elephants. There’s a link in the show notes if you want to find out more and maybe donate to the program to help these adorable teeny-tiny wildcats.

Finally, Henry suggested the Arctic tern, a bird that lives…pretty much everywhere, in fact, not just the Arctic. It breeds along the coasts in the northern parts of the northern hemisphere, including parts of Canada, Greenland, northern Europe, and Siberia, but after its babies are grown and the short northern summer comes to an end, it takes off for the southern hemisphere and spends the winter—which is summer in the southern hemisphere—around South Africa and Australia and New Zealand, all the way down to the Antarctic. When that summer ends, it flies back north to breed again. That’s an astoundingly long migration.

The Arctic tern spends most of its life flying above the ocean, hunting for small animals like fish, krill, amphipods, and crabs. It’s not a picky eater, though. It will also eat worms, insects, and berries, although it mostly eats these land foods when it’s nesting. It’s a beautiful bird that looks a little like a seagull, but is more lightly built and slender than most gulls. It’s white and pale gray with a black cap that extends down the back of the neck, a red bill, and short red legs and webbed feet. Its tail is forked like a swallow’s tail and it has long wings, which allow it to catch even the smallest sea breeze and fly extremely fast. Its wingspan is about 2.5 feet across, or 75 cm.

The Arctic tern mates for life. Even though the male and female have traveled literally around the world separately for most of the year, they both return to the same nesting ground, find each other, and start their summer courtship. The pair will fly high together with the female chasing the male, and then they’ll fly lower where the male will catch a little fish and offer it to the female. On land, they’ll do a little courtship dance where they raise and lower their tail and wings while strutting around together. Finally the pair decides where they want to build a nest.

The nest isn’t fancy, just a little scooped out place in the ground with maybe some grass in it. Parents take turns keeping the eggs warm and defending the nest from potential predators. It’s an aggressive bird and will even attack polar bears and drive them away, even though it’s just a delicate little bird. It will dive at the predator’s face and peck with its strong, sharp bill. Once the babies hatch, both parents feed the chicks until they learn how to fly.

An Arctic tern chick is possibly the cutest bird you will ever see, at least today. It’s gray and white with short legs, and it’s super super fluffy. The coloration helps it blend in with the rocks around the nesting site.

The Arctic tern travels over 40,000 miles every single year, or more than 70,000 km, and still manages to find its way back to the same breeding colony. How does it know where it is and where it’s going? Like many birds, it can sense the earth’s magnetic field. It combines this sense with where the sun is in the sky and can pinpoint exactly where it is in the world and where it needs to go. It’s like having built-in Google Maps.

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

Thanks for listening!

Episode 236: Updates 4 and a Mystery Snake!

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It’s our fourth annual updates and corrections episode! I’ve already had to make a correction to this episode!

Further reading:

Cassowary, a rare emu-like bird, attacks and kills Florida man, officials say

The dog Bunny’s Facebook page

3D printed replicas reveal swimming capabilities of ancient cephalopods

Enormous ancient fish discovered by accident

A rare observation of a vampire bat adopting an unrelated pup

Pandemic paleo: A wayward skull, at-home fossil analyses, a first for Antarctic amphibians

Neanderthals and Homo sapiens used identical Nubian technology

Entire genome from Pestera Muierii 1 sequenced

Animal Species Named from Photos

Cryptophidion, named from photos:

The sunbeam snake showing off that iridescence:

Show transcript:

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

 

It’s our fourth annual updates and corrections episode, and to keep it especially interesting we’ll also learn about a mystery snake. Make sure to check the show notes for lots of links if you want to learn more about these updates.

 

First, we have a small correction from episode 222. G emailed with a link about a Florida man who was killed by a cassowary in 2019, so cassowaries continue to be dangerous.

 

We also have a correction from episode 188, about the hyena. I called hyenas canids at one point, and although they resemble canids like dogs and wolves, they’re not canids at all. In fact, they’re more closely related to cats than dogs. Thanks to Bal for the correction!

 

In response to the talking animals episode, Merike told about a dog who uses computer buttons to communicate. The dog is called Bunny and she’s completely adorable. I’ll link to her facebook page. I have my doubts that she’s actually communicating the way it looks like she is. She’s obviously a clever dog but I don’t think she understands the English language so well that she can choose verbs like “is” from her list of words. I think she’s probably mostly taking unconscious cues from her owner. But I would be happy to be proven wrong.

 

Following up from our recent deep-sea squid episode, a team of paleontologists studying ancient cephalopods 3-D printed some replicas of what the animals would have looked like while alive. Then they took the models into a swimming pool and other water sources to study how their shells affected the way they could move through the water. They discovered that a type of cephalopod with a straight shell, called an orthocone, probably mostly moved up and down in the water to find food and could have moved extremely fast in an upward or downward direction. A type of cephalopod with a spiral shaped shell, called a torticone, also spun slightly as it moved around. The same team has previously worked with 3-D models of ammonoids, which we talked about in episode 86. The models don’t just look like the living animals, they have the same center of balance and other details, worked out mathematically.

 

Speaking of ancient animals, a collector in London bought a fossil found in Morocco thinking it was part of a pterodactyl skull. When the collector asked a palaeontologist to identify it, it turned out to be a fossilized coelacanth lung. The collector donated the fossil for further study, and the palaeontologist, David Martill, worked with a Brazilian coelacanth expert, Paulo Brito, to examine the fossil.

 

The fossil dates to the Cretaceous, about 66 million years ago, and is bigger than any coelacanth lung ever found. Modern coelacanths grow a little over six feet long at most, or 2 meters, but the estimated length of this Coelacanth is some 16 ½ feet, or 5 meters. The fossil is being donated to a university in Morocco.

 

We talked about vampire bats way back in episode 11, and I love bats and especially vampire bats so I try to keep an eye on new findings about them. Everyone thinks vampire bats are scary and creepy, but they’re actually social, friendly animals who don’t mean to spread rabies and other diseases to the animals they bite. It just happens.

 

Vampire bats live in colonies and researchers have long known that if a female dies, her close relations will often take care of her surviving baby. Now we have evidence that at least sometimes, the adoptive mother isn’t necessarily related to the birth mother. It’s from a recently published article based on a study done in 2019.

 

A team researching how unrelated vampire bats form social bonds captured 23 common vampire bats from three different colonies and put them together in a new roost where their interactions could be recorded by surveillance cameras. One particular pair of females, nicknamed Lilith and BD, became good friends. They groomed each other frequently and shared food. If you remember from episode 11, vampire bats share food by regurgitating some of the blood they drank earlier so the other bat can lap it up. Since vampire bats can starve to death in only a few nights if they can’t find blood, having friends who will share food is important.

 

During the study, Lilith gave birth to a baby, but shortly afterwards she started getting sick. She had trouble getting enough food and couldn’t groom or take care of her baby as well as a mother bat should. Her friend BD helped out, grooming the baby, sharing food with Lilith, and eventually even nursing the baby when Lilith got too sick to produce milk. After Lilith died, BD adopted the baby as though it was her own. By the time the study ended, BD was still caring for the baby bat.

 

We talked about spiders in the Antarctic in episode 221, and mentioned that Antarctica hasn’t always been a frozen wasteland of ice and snow. In a new study of fossils found in Antarctica, published in May of 2021, the first Antarctic amphibian skull has been identified. It lived in the early Triassic, not long after the end-Permian mass extinction 252 million years ago. It’s been named Micropholis stowi and is a new species of temnospondyl that was previously only known from South Africa. The skull, along with other fossils from four individuals, was discovered in the Transantarctic Mountains in 2017 and 2018, and the research team studied them from home during the 2020 pandemic lockdowns.

 

In news about humans and our extinct close relations, a new finding shows that Neanderthals and humans used the same type of tools. Researchers studied a child’s tooth and some stone tools, all found in a cave in the mountains of Palestine, and determined that the tooth was from a Neanderthal child, not a human. The tooth was discovered in 1928 but was in a private collection until recently, so no one had been able to study it before now. The tools are a specific type developed in Africa that have only been found associated with humans before. Not only that, but until this finding, there was no evidence that Neandertals ever lived so far south.

 

The child is estimated to have been about nine or ten years old, which is the age when you’re likely to lose a baby tooth as your adult teeth start growing in. I like to think about the child sitting next to their Mom or Dad, who were either creating new tools or using ones they’d already made to do something like cut up food for that evening’s dinner. Maybe the child was supposed to be helping, and they were, but they had a loose tooth and kept giving it a twist now and then, trying to get it to come out. Then, finally, out it popped and bounced onto the cave floor, where it was lost for the next 60,000 years.

 

Researchers have just announced that they’ve sequenced the genetic profile of a woman who lived in what is now Romania about 35,000 years ago. Judging from her skull shape and what is known about ancient humans in Europe, the team had assumed she would be rather restricted in her genetic diversity but that she would show more Neanderthal ancestry than modern humans have. Instead, they were surprised to find that the woman had much more genetic diversity than modern humans but no more Neanderthal genes than most human populations have these days.

 

This was a surprise because modern humans whose prehistoric ancestors migrated out of Africa show much less genetic diversity than modern humans whose ancestors stayed in Africa until modern times. Researchers have always thought there was a genetic bottleneck at some point during or not long after groups of humans migrated out of Africa around 80,000 years ago. Lots of suggestions have been made about what might have caused the bottleneck, including disease, natural disaster, or just the general hardship of living somewhere where humans had never lived before. A genetic bottleneck happens when a limited number of individuals survive long enough to reproduce—in other words, in this case, if so many people die before they have children that there are hardly any children left to grow up and have children of their own. To show in the general population as it does, the bottleneck has to be widespread.

 

Now researchers think the genetic bottleneck happened much later than 80,000 years ago, probably during the last ice age. Humans living in Europe and Asia, where the ice age was severe, would have had trouble finding food and staying warm.

 

I’m getting close to finishing the Strange Animals Podcast book, which I’ll talk about a little more in our Q&A episode later this week. It’s a collection of the best mystery animals we’ve covered on the podcast, along with some new mystery animals, and I’m working hard to update my research. If you remember back in episode 83, about mystery big cats, we discussed the Barbary lion, which was thought to be an extinct subspecies of lion that might not actually be extinct. Well, when I looked into it to see if any new information had turned up, I found more than I expected. I rewrote those paragraphs from episode 83 and I’ll read them here as an update:

 

Lions live mostly in Africa these days, but were once common throughout southern Asia and even parts of southern Europe. There even used to be a species called the American lion, which once lived throughout North and South America. It only went extinct around 11,000 years ago. The American lion is the largest species of lion ever known, about a quarter larger than modern African lions. It probably stood almost 4 feet tall at the shoulder, or 1.2 meters. Rock art and pieces of skin preserved in South American caves indicate that its coat was reddish instead of golden. It lived in open grasslands like modern lions and even in cold areas.

 

Much more recently, the Barbary lion lived in northern Africa until it was hunted to extinction in the area. The Barbary lion was the one that battled gladiators in ancient Rome and was hunted by pharaohs in ancient Egypt. It was a big lion with a dark mane, and was thought to be a separate subspecies of lion until genetic analysis revealed in 2006 that it wasn’t actually different from Panthera leo leo.

 

The last wild Barbary lion was sighted in 1956, but the forest where it was seen was destroyed two years later. The lions in a few zoos, especially in Ethiopia and Morocco, are descended from Barbary lions kept in royal menageries for centuries.

 

Lions are well known to live on the savanna despite the term king of the jungle, but they do occasionally live in open forests and sometimes in actual jungles. In 2012 a lioness was spotted in a protected rainforest in Ethiopia, and locals say the lions pass through the reserve every year during the dry season. That rainforest is also one of the few places left in the world where wild coffee plants grow. So, you know, extra reason to keep it as safe as possible.

 

Finally, we’ll finish with a mystery snake. In 1968, during the Vietnam War, the United States Naval Medical Research Unit discovered a small snake in central Vietnam. It was unusual enough that they decided to save it for snake experts to look at later, but things don’t always go to plan during wartime. The specimen disappeared somewhere along the line. Fortunately, there were photographs.

 

The photos eventually made their way to some biologists, and in 1994 a paper describing the snake as a new species was published by Wallach and Jones. They based their description on the photos, which were good enough that they could determine details like the number of scales on the head and jaw. They named it Cryptophidion annamense and suggested it was a burrowing snake based on its characteristics.

 

Other biologists thought Cryptophidion wasn’t a new species of snake at all. In 1996 a pair of scientists published a paper arguing that it was just a sunbeam snake. The sunbeam snake is native to Southeast Asia, including Vietnam, and can grow over 4 feet long, or 1.3 meters. It’s chocolate-brown or purplish-brown but has iridescent scales that give it a rainbow sheen in sunshine. It’s a constricting snake, meaning it squeezes the breath out of its prey to kill it, but it only eats small animals like frogs, mice, and other snakes. It’s nocturnal and spends a lot of its time burrowing in mud to find food.

 

Wallach and Jones, along with other scientists, argued that there were too many differences between the sunbeam snake and Cryptophidion for them to be the same species. But without a physical specimen to examine, no one can say for sure if the snake is new to science or not. If you live in or near Vietnam and find snakes interesting, you might be the one to solve this mystery.

 

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

 

Thanks for listening!

Episode 221: Arachnids in the Antarctic!

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Thanks to Ella for this week’s suggestion. There may not technically be spiders in the Antarctic, but there are mites.

A nunatak (note the size of the research vehicles at the bottom left):

I don’t have any pictures of the Antarctic mites, so here are some red velvet mites, although they’re giants compared to their Antarctic cousins:

Show transcript:

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

This week we’re going to have a short episode, because I get my second Covid-19 vaccine on the Thursday before this episode goes live and I want to have the episode all finished before then. That way if I feel bad afterwards I can rest. Thanks to Ella for this week’s suggestion!

Back in episode 90, about some mystery spiders, I mentioned that spiders live everywhere in the world except Antarctica. Well, guess what. Ella sent me some links about spiders that live in…Antarctica!

Antarctica is a landmass at the South Pole, specifically a continent about twice the size of Australia. It looks bigger than it really is because ice projects out from the land and is only supported by water, called an ice shelf. It’s not a little bit of ice, either. It’s over a mile thick, or nearly 2 km. The ice is called the Antarctic ice sheet and it covers 98% of the continent. The only places not covered in ice are some rock outcroppings and a few valleys, called dry valleys because they basically get no precipitation, not even snow and certainly not rain. Researchers estimate that it hasn’t rained in these dry valleys in almost two million years. There are no plants, just gravel. There are no animals but some bacterial life that live inside rocks and under at least one glacier. Scientists have used these dry valleys to test equipment designed for Mars. This is not a hospitable land. Everything that lives in Antarctica is considered an extremophile.

That doesn’t mean there’s no life in Antarctica, though, just that it’s only found in a few places, mostly along the coast or on nearby islands. Emperor penguins and Adelie penguins, several species of seal, and some sea birds live at least part of their lives in and around Antarctica, as do some whales. There are lichens, algae, and a few low-growing plants like liverwort and moss. And there are some invertebrates, although not very many and not large at all. The largest is a flightless midge that only grows 6 mm long. But what we’re interested in today are mites found only in Antarctica.

We talked about mites in episode 186 when we learned about the red velvet mite. Mites are arachnids, although they’re not technically spiders, but frankly we’re just quibbling at this point. It has eight legs and is in the class Arachnida, so I say there are spiders in Antarctica. Or close enough.

There are 30 species of mite in Antarctica. They mostly live on islands throughout the Antarctic peninsula, which sticks out from one side of the continent like a tail pointing at the very tip of South America. All the mites eat moss, algae, and decomposing lichens. They’re also teeny-tiny, less than a millimeter long.

One type of mite is found on the mainland of East Antarctica instead of just on islands. It’s called Maudheimia and it only lives on big rock outcroppings that stick up through the ice. These rocks are called nunataks and are covered with lichens. But nunataks are far apart, sometimes hundreds of miles apart, and the mites are so tiny they’re just about microscopic. How did they get from one nunatak to the next?

To find out, we have to learn some history about Antarctica. It hasn’t always been at the South Pole. It was once part of the supercontinent Gondwana, and 500 million years ago it was right smack on the equator. You know, tropical. As the centuries passed and the continents continued their slow, constant dance around the Earth, Gondwana drifted southward and broke apart. Antarctica was still connected to Australia on one side and South America on the other, and was still subtropical. Then it broke off from Australia around 40 million years ago, drifted farther southward, and ultimately, about 25 million years ago, separated from South America. Ever since it’s been isolated at the South Pole, and by 15 million years ago it was ice-covered.

Fossils of dinosaurs and other ancient animals have been discovered in Antarctica, but it’s hard to find fossils and excavate them when the ground is under a mile of ice. The animals and plants that once lived in Antarctica went extinct gradually as its climate became less and less hospitable, and most of the remaining holdouts went extinct when the ice age began and the continent’s climate was even colder and harsher than it is now.

But one animal remains, toughing it out on rock outcroppings where the temperature can drop to -31 degrees Fahrenheit, or -35 Celsius. Maudheimia, the brave little mite.

Maudheimia was probably common throughout Antarctica’s mountains before the big freeze happened, and would have already been well adapted to the cold of high elevations. As the continent grew colder and colder, the little mite adapted even more. The fluids in its body contain an organic antifreeze agent so it doesn’t freeze solid. As the ice covered more of its home, it migrated, in its tiny way, to the rocks that stayed ice-free and allowed lichen to survive too. It’s reasonably common despite its restricted habitat, which is good because the female Maudheimia only lays one egg every year or two. There are four species known.

Maudheimia probably isn’t the only animal that survived Antarctica’s ice age, though. Species of springtail only found in Antarctica live alongside Maudheimia, and there are tardigrades and tiny nematode worms around too. All these were probably around long before the end of the ice age around 12,000 years ago.

There may be other microscopic or nearly microscopic animals we haven’t discovered yet. The Antarctic is the only place in the world that humans have never colonized, although a small number of people live in scientific outposts while conducting research of various kinds. There’s a lot we don’t know about the continent.

For instance, there are at least 400 subglacial lakes in Antarctica. The lakes form between the bedrock and the ice sheet, like a little bubble of water. Iceland, Greenland, and Canada have some too. They’re hard to study, naturally, because it requires drilling through over a mile of ice to get a water sample. So far researchers have discovered extremophile microbes in these lakes, but so few samples have been taken that we certainly don’t know everything that’s down there. Most of the lakes occasionally overflow into nearby subglacial lakes, but at least some appear to have been isolated under the ice for potentially millions of years. They may contain bacteria and other microbial life that are radically different from modern species.

There’s one other place that we know has a subglacial lake, discovered in 2018. It’s on the planet Mars. I wonder if there’s anything living in that one.

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!