Episoder
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Thanks to Alyx for this week's suggestion, the cookie cutter shark!
Further reading:
If You Give a Shark a Cookie
The business end of the cookie cutter shark:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we’re going to learn about a little shark suggested by Alyx, but first let’s learn about something else that might be related to the shark.
In the 1970s, the U.S. Navy started having trouble with the navigation of their submarines. The Ohio-class submarine had what was called a sonar dome that was filled with oil, and the oil helped transmit sound. But repeatedly the subs would lose navigation abilities, and investigations turned up strange chunks removed from the electric cables, the oil lines, the sound probes, and the sonar dome itself—anywhere made of rubber that was soft enough for what looked like a hole saw to damage.
The Navy thought they were dealing with a state-of-the-art weapon. The United States and the former Soviet Union were bitter enemies, so the Navy thought the USSR had invented a technologically sophisticated underwater stealth drone of some kind that could damage the subs and leave no trace—nothing but circular chunks removed from the sonar dome and its components.
Thirty submarines were damaged before the Navy figured out the cause. It wasn’t a super-secret weapon at all. It was just a little fish called the cookie-cutter shark.
The cookie cutter shark doesn’t look very scary. It only grows 22 inches long at most, or 56 cm, and is brown in color. It has lots of very sharp evenly spaced teeth on its lower jaw, but compared to a great white shark, it’s nothing to worry about. But somehow it was able to disable 30 of the world’s most advanced submarines at the time.
That’s because of how the cookie cutter shark eats, which is also how it gets its name. It picks a target fish or some other animal, such as a whale or a seal, or possibly the sonar dome of an Ohio-class submarine, and sneaks up to it. It’s just a little fish and its coloration helps it blend in with its surroundings, so most animals barely notice it. It has lips that act like a suction cup, so quick as a wink it sticks itself to the animal, bites down, and spins around. In moments it’s cut a circular chunk out of the animal’s side like a horrible cookie, which it swallows, and by the time the animal even realizes it’s hurt, the cookie cutter shark is long gone.
The shark used to be called the cigar shark because of its shape. It wasn’t until 1971 that experts realized how the cookie cutter shark eats. Until then the circular wounds on fish and whales and other animals were thought to be from lamprey bites or from some kind of parasite.
The cookie cutter shark does have teeth in its upper jaw but they’re much smaller than the lower teeth. When it sheds its lower teeth to replace them, instead of shedding just one tooth, it sheds them all at once. Like most sharks, it swallows its old teeth so it can reuse the calcium to grow new teeth.
The shark also has photophores on the underside of its body that glow greenish, which is a common way that some fish escape predators from below. A big fish looking up toward the surface of the water high above it sees a lot of light shining down from the sun, so a fish with a glowing underside just blends in. But in the case of the cookie cutter shark, it has a strip of skin on its underside without photophores, and from below that strip shows up. It’s a sort of collar that’s actually darker brown than the rest of the fish. It looks, in fact, like a tiny fish silhouetted against the surface. The would-be predator fish approaches, expecting an easy meal. Instead, the cookie cutter shark darts around and takes a big bite out of the fish, then takes off. It’s a remarkably fast swimmer, but most of the time it hangs almost motionless in the water waiting for another animal to approach. -
Thanks to Riley and Dean, Elizabeth, and Leo for their suggestions this week!
Further reading:
Groundbreaking study reveals extensive leatherback turtle activity along U.S. coastline
A bearded dragon:
The tiny bog turtle:
The massive leatherback sea turtle:
The beautiful hawksbill turtle [photo by U.S. Fish and Wildlife Service]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we’re going to learn about some reptiles suggested by four different listeners: Riley and Dean, Elizabeth, and Leo.
We’ll start with the brothers Riley and Dean. Dean wants to learn more about the bearded dragon, and that may have something to do with a certain pet bearded dragon named Kippley.
“Bearded dragon” is the name given to any of eight species of lizard in the genus Pogona, also referred to as beardies. They’re native to Australia and eat plants and small animals like worms and insects. They can grow about two feet long, or 60 cm, including the tail, but some species are half that length. Females are a little smaller than males on average.
The bearded dragon gets its name because its throat is covered with pointy scales that most of the time aren’t very noticeable, but if the lizard is upset or just wants to impress another bearded dragon, it will suck air into its lungs so that its skin tightens and the spiky scales under its throat and on the rest of its body stick out. They’re not very sharp but they look impressive. Since the bearded dragon can also change color to some degree the same way a chameleon can, when it inflates its throat to show off its beard, the beard will often darken in color to be more noticeable. Both males and females have this pointy “beard.”
Bearded dragons that are sold as pets these days are more varied and brighter in color than their wild counterparts, although wild beardies can be brown, reddish-brown, yellow, orange, and even white. Australia made it illegal to catch and sell bearded dragons as pets in the late 20th century, but there were already lots of them outside of Australia by then. Pet bearded dragons are mainly descended from lizards exported during the 1970s, which means they’re quite domesticated these days and make good pets.
Like some other reptiles and amphibians, the bearded dragon has a third eye in the middle of its forehead. If you have a pet beardie and are about to say, “no way, there is definitely not a third eye anywhere, I would have noticed,” the eye doesn’t look like an eye. It’s tiny and is basically just a photoreceptor that can sense light and dark. Technically it’s called a parietal eye and researchers think it helps with thermoregulation.
Next, Riley wants to learn about turtles, AKA turbles, and especially wants everyone to know the difference between a tortoise and a turtle. It turns out that while many turtles are just fine living on land, they’re often more adapted to life in the water. Turtles have a more streamlined shell and often flipper-like legs or webbed toes. Tortoises only live on land and as a result they have shells that are more dome-shaped, and they have large, strong legs that resemble those of a tiny elephant.
You can’t always go by an animal’s common name to determine if it’s a tortoise or a turtle, but it’s also not always clear whether an animal is a tortoise or a turtle at first glance. Take the eastern box turtle, for instance, which is common in the eastern United States. It has a domed carapace, or shell, but it’s still a turtle, not a tortoise. And, I’m happy to say, it can swim quite well. This is a relief to find out because when I was about six years old, my mom visited someone who had kids a little older than me. I didn’t know them but they were nice and showed me the swampy area near their house. At one point one of the older boys found a box turtle, took it over to a little bridge over a pond, and dropped it in the water. I screamed, -
Manglende episoder?
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Thanks to Molly and Mila for suggesting the anteater and its relations this week!
Further reading:
How anteaters lost their teeth
The giant anteater has a long tongue and a little mouth, and adorable babies:
The giant anteater has a weird skull [photos by Museum of Veterinary Anatomy FMVZ USP CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=72183871]:
The tamandua is like a mini giant anteater that can climb trees:
The silky anteater looks like a weird teddy bear [photo by Quinten Questel - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30287945]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we’re going to talk about some unusual mammals, suggested by Molly and Mila. It’s a topic I’ve been meaning to cover for almost two years and now we’re finally going to learn about it! It’s the anteater and its close relations, including a creepy anteater cryptid that would have fit in just fine during monster month.
A lot of animals are called anteaters because they eat ants, but the anteaters we’re talking about today belong to the suborder Vermilingua, meaning “worm tongue.” That’s because they all have long, sticky tongues that they use to lick up ants, termites, and other insects. Anteaters are native to Central and South America and are closely related to sloths, and more distantly related to armadillos.
The sloth and anteater share a common ancestor who lived around 60 million years ago, a little animal that mainly ate worms and insect larvae and probably lived in burrows. Because its food was soft and didn’t need a lot of chewing, when a mutation cropped up that caused its teeth to be weak, it didn’t matter. It wasn’t using its teeth anyway. When the first anteaters evolved from this ancestral species, they didn’t need teeth either, and gradually they lost their teeth entirely. Modern anteaters have no teeth at all.
Sloths also evolved from this weak-toothed ancestor, and sloths eat plants. Plants need a lot of chewing, and most animals that eat plants have really strong teeth, but sloths retained the genetics for weak teeth. They don’t even have an enamel coating on their teeth, and instead of grinding molars, their teeth are basically soft little pegs. Luckily for the sloth, the little peg teeth do continue to grow throughout its life, so it never wears its teeth down so far it can’t chew.
Anteaters, sloths, and their distant relation the armadillo all share the same type of vision from their shared ancestor too. They can’t see colors at all but have good vision in low light, which is why scientists think they all evolved from an animal that spent most of its time underground hunting for worms. Anteaters have strong claws that allow them to dig into termite and ant nests, and armadillos spend a lot of time in burrows they dig. We don’t actually know what the common ancestor of these related animals looked like because we haven’t found any fossils of it yet.
In the past, scientists thought that pangolins and aardvarks were related to anteaters because they all have similar adaptations to a similar diet, but that’s just another example of convergent evolution. We talked about pangolins and aardvarks back in episode 65, as well as the giant anteater.
The giant anteater is the one most people know about. It earns the name giant because it can grow almost eight feet long, or 2 1/2 meters, if you include the tail. Its fur is brown and cream with a distinctive black stripe from its chest to its back that scientists used to think acted as camouflage. Because the black fur is outlined with white, making it stand out, scientists now think it’s used as a warning to potential predators, because the giant anteater can be dangerous. If it feels threatened, it will rear up on its hind legs, using its long tail as a prop, to slash at a predator. Its claws are so big that it knuckle-walks on its for... -
Thanks to Ezra and Leo for suggesting these two sea monsters this week! Happy Halloween!
Further reading:
Legend of Chessie alive, well in Maryland
Here be sea monsters: We have met Chessie and...is it us?
Not actually a kraken, probably:
Not actually Chessie but an atmospheric photo of a toy brontosaurus:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
Just a few days remain in October, so this is our Halloween episode and the end of monster month for another year! We had so many great suggestions for Halloween episodes that I couldn’t get to them all, but I might just sprinkle some in throughout the other months too. We have two great monsters to talk about this week, suggested by Ezra and Leo, the kraken and Chessie the sea serpent.
First, as always on our Halloween episode, we have a few housekeeping details. If anyone wants a sticker, feel free to email me and I’ll send you one, or more than one if you like. That offer is good all the time, not just now. I don’t have any new stickers printed but I do have lots of the little ones with the logo and the little ones with the capybara.
I also don’t have any new books out this year, but you can still buy the Beyond Bigfoot & Nessie book if you like. I am actually working on another book about mystery animals, tentatively titled Small Mysteries since it’s going to be all about mysteries surrounding small animals like frogs and invertebrates that often get overlooked. I’m hoping to have it ready to publish in early 2026 or so. I don’t know that I’ll do another Kickstarter for it since that was a lot of work, and I just finished a Kickstarter for more enamel pins and just can’t even think about the stress of doing another crowdfunding campaign anytime soon. Also, I hate to keep asking listeners for money.
Anyway, one of the things I don’t like about Beyond Bigfoot & Nessie is that I didn’t cite my sources properly, so for the Small Mysteries book I’m being very careful to have footnotes on pretty much every page so that anyone who wants to double-check my information can do so easily.
But all that is in the future. Let’s celebrate Halloween now with a couple of sea monsters!
We’ll start with Ezra’s suggestion, the kraken. It’s a creature of folklore that has gotten confused with lots of other folklore monsters. We don’t know how old the original legend is, but the first mention of it in writing dates to 1700, when an Italian writer published a book about his travels to Scandinavia. One of the things he mentions is a giant fish with lots of horns and arms, which he called the “sciu-crak.” This seems to come from the Norwegian word meaning sea krake.
“Krake” is related to the English word crooked, and it can refer to an old dead tree with crooked branches, or tree roots, or something with a hook on the end like a boat hook, or an anchor or drag, or various similar things related to hooks or multiple prongs. That has led to people naturally assuming that the kraken had many arms and was probably a giant squid, and that may be the case. But there’s another possibility, because in many old uses of the word krake, it means something weak or misshapen, like a rotten old dead tree. In the olden days in Norway, people thought that if you spoke about an animal by name, the spirit that protected that animal would hear you. Some historians think that whale-hunters referred to whales as krake so the whale’s protective spirit wouldn’t guess that they were planning a whale-hunt. Who would refer to a huge, strong animal like a whale as weak and crooked, after all?
Whatever its origins, the kraken’s modern form is mainly due to a Danish bishop called Erik Pontoppidan. He wrote about the kraken in 1753, and embellished the story by saying the kraken could reach out of the ocean with its long arms to grab sailors or just pull an entire ship down into the water and sink it. -
Thanks to Eesa for suggesting this week's topic, the pliosaur Predator X!
Further reading:
Predator X / Pliosaurus funkei [you can find lots of interesting pictures here, some artwork and some skeletal diagrams]
Kronosaurus had a big skull with big teeth:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
We’re one week closer to Halloween, and that means the monsters are getting more monster-y, at least in name, although I wouldn’t want to meet this one in person. It’s referred to as Predator X, and thanks to Eesa for suggesting it!
Fortunately for everyone who likes to swim and boat in the ocean, Predator X has been extinct for around 145 million years. It’s a type of marine reptile called a pliosaur, Pliosaurus funkei, but there was nothing funky about it. It was huge, fast, and incredibly strong. Also, the funky part of the name comes from the couple who originally discovered the first specimen, who had the last name of Funke.
We only have two Predator X specimens right now, both of them found in the same rock formation from a Norwegian island. The remains were first discovered in 2004 but the process of recovering them took many years. Because winters in Norway are very cold, the exposed rocks were subject to freezing temperatures that had broken a lot of the fossils into fragments, and some of the fossils crumbled into pieces as they dried out. All told, 20,000 pieces were recovered and painstakingly fit back together like a gigantic jigsaw puzzle made of fossilized bones.
Neither specimen is complete but we have enough bones that scientists can estimate the animal’s size when it was alive—and it was huge! It probably grew up to 39 feet long, or 12 meters, and some individuals would certainly have been bigger. Initial estimates were even longer, up to 50 feet, or over 15 meters, but that was before the specimens were fully studied.
Like other pliosaurs, predator X had a short tail and big teeth in its long jaws. Its head was massive, around 7 feet long, or 2 meters, and its front flippers were probably about the same length. It had four flippers, and researchers think its front flippers did most of the work of swimming, with the rear flippers acting as a rudder, but it could probably use its back flippers for a little extra boost of speed when it needed to. But it was a strong, fast swimmer no matter what, probably as fast as a modern orca, and very maneuverable. It had to be, because it ate other marine reptiles like plesiosaurs that were themselves very fast swimmers. It undoubtedly also ate sea turtles and fish, and probably pretty much anything else it could catch. It didn’t eat whales because this was long, long before whales evolved.
Predator X got its nickname from reporters back when the paleontologists thought it was 50 feet long. It didn’t have a name yet so it got called Predator X because that sounded impressive (and it is), but it isn’t the only giant pliosaur known.
Kronosaurus was originally described in 1924 from fossils discovered in Australia, and current estimates of its size agree that it could probably grow to around 33 feet long, or 10 meters. This may be a low estimate, though, because the size of the biggest skull found might have been over 9 feet long, or 2.85 meters, although the skull isn’t complete so its full size is just an estimate. Pliosaurs do have big heads, but if Kronosaurus’s skull really is longer than predator X’s skull, it was probably a bigger animal overall.
Kronosaurus’s fossils have only been found in an ancient inland sea that covered most of Queensland and Central Australia until about 100 million years ago. It was probably a relatively shallow, cold sea, and although it had all the marine animals you’d expect for the time, like sharks, ammonites, ichthyosaurs, plesiosaurs, lungfish, sea turtles, and lots more, Kronosaurus was the apex predator. It was so big and deadly that a full-grown Kronosaurus didn’t have to worry ... -
Thanks to Nora and Richard from NC this week as we learn about some scary-sounding reptiles, including the hoop snake!
Further reading:
The Story of How the Giant “Terror Skink” Was Presumed Extinct, Then Rediscovered
San Diego’s Rattlesnakes and What To Do When They’re on Your Property
Snake that cartwheels away from predators described for the first time
Giant new snake species identified in the Amazon
The terror skink, AKA Bocourt's terrific skink [photo by DECOURT Théo - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=116258516]:
The hoop snake according to folklore:
The sidewinder rattlesnake [photo taken from this article]:
The dwarf reed snake [photo by Evan Quah, from page linked above]:
The green anaconda [photo by MKAMPIS - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=62039578]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
As monster month continues, we’re going to look at some weird and kind of scary, or at least scary-sounding, snakes and lizards. Thanks to Nora and Richard from NC for their suggestions this week!
We’ll start with the terror skink, whose name should inspire terror, but it’s also called Bocourt’s terrific skink, which is a name that should inspire joy. Which is it, terror or joy? I suppose it depends on your mood and how you feel about lizards in general. All skinks are lizards but not all lizards are skinks, by the way.
The terror or possibly terrific skink lives on two tiny islets, which are miniature islands. These islets are themselves off the coast of an island called the Isle of Pines, but in French, which I cannot pronounce. The Isle of Pines is only 8 miles wide and 9 miles long, or 13 by 15 km, and is itself off the coast of the bigger island of New Caledonia. All these islands lie east of Australia. Technically the islets where the skink lives are off the coast of another islet that is itself off the coast of the Isle of Pines, which is off the coast of New Caledonia, but where exactly it lives is kept a secret by the scientists studying it.
The skink was described in 1876 but only known from a single specimen captured on New Caledonia around 1870, and after that it wasn’t seen again and was presumed extinct. Colonists and explorers brought rats and other invasive animals to the New Caledonian islands, which together with habitat loss have caused many other native species to go extinct.
But in December 2003, a scientific expedition studying sea snakes around the New Caledonian islands caught a big lizard no one recognized. Once the expedition members realized it was a terror skink, alive and well, they took lots of pictures and videos of it and then released it back into the wild. Since then, more specimens have been discovered during four different expeditions, but only on the islets, not on any of the bigger islands. It’s so critically endangered that its location has to be kept secret, because if someone captures some of the lizards to sell on the illegal pet market, the species could easily be driven to extinction.
The terror skink is gray-brown with darker stripes, a long tail, and a slightly downturned mouth that makes it look grumpy. It grows about 20 inches long, or 50 cm, including its tail. This is really big for a skink, so technically it’s a giant skink.
It gets the name terror skink from its size and from its teeth, which are large and curved like fangs. It mainly eats one particular species of land crab, which is why its jaws are so strong and its teeth are so sharp, so it can bite through the crab’s exoskeleton.
Another lizard with a spooky name that has been presumed extinct is the gray ghost lizard, suggested by Richard from NC. It’s more properly called the giant Tongan ground skink, and it’s native to some more South Pacific islands—specifically, the Tongan Islands. -
Thanks to Murilo for suggesting El Gran Maja for our first monster month episode of 2024!
Further reading:
The Loch Ness Monster: If It’s Real, Could It Be an Eel?
Further watching:
Borisao Blois's YouTube channel [I have not watched very many of his videos so can't speak to how appropriate they all are for younger viewers]
El Gran Maja, YouTube star:
The European eel [photo by GerardM - http://www.digischool.nl/bi/onderwaterbiologie/, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=284678]:
A supposed 21-foot eel, a product of trick photography:
The slender giant moray eel [photo by BEDO (Thailand) - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=40262310]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
It’s monster month, where we talk about weird, mysterious, and sometimes spooky creatures! This year I’ve decided to be less spooky and more weird, so let’s kick off the month with an episode all about gigantic eels. Thanks to Murilo for suggesting our first giant eel, El Gran Maja.
El Gran Maja is an eel that is supposed to live off the coast of northern Puerto Rico, and it’s supposed to grow 675 meters long. That’s 2,215 feet, or almost half a mile. That is an excessive amount of eel.
Obviously, an eel that big couldn’t actually exist. By the time its front end noticed danger, its back end could already be eaten by a whole family of sharks. But maybe it was based on a real eel that grows really long. Let’s take a look at some eels we know exist, and then we’ll return to El Gran Maja and learn some very interesting things about it.
Eels are fish, but not every animal that’s called an eel is actually an eel. Some are just eel-shaped, meaning they’re long and slender. Electric eels aren’t actually eels, for instance, but are more closely related to catfish. Most eels live in the ocean at the beginning and end of their lives, and freshwater in between.
For example, the European eel has a life cycle that’s pretty common among eels. It hatches in the ocean into a larval stage that looks sort of like a transparent leaf. Over the next six months to three years, the larvae swim and float through the ocean currents, closer and closer to Europe, feeding on plankton and other tiny food. Toward the end of this journey, they grow into their next phase, where they resemble eels instead of leaf-shaped tadpoles, but are still mostly transparent. They’re called glass eels at this point. The glass eels make their way into rivers and slowly migrate upstream. Once a glass eel is in a good environment it metamorphoses again into an elver, which is basically a small eel. As it grows it gains more pigment until it’s called a yellow eel. Over the next decade or two it grows and matures, until it reaches its adult length—typically around 3 feet, or about a meter. When it’s fully mature, its belly turns white and its sides silver, which is why it’s called a silver eel at this stage. Silver eels migrate more than 4,000 miles, or 6500 km, back to the Sargasso Sea to spawn, lay eggs, and die.
One place where European eels live is Loch Ness in Scotland, and in the 1970s the idea that sightings of the Loch Ness Monster might actually be sightings of unusually large eels became popular. A 2018 environmental DNA study brought the idea back up, since the study discovered that there are a whole, whole lot of eels in Loch Ness. The estimate is a population of more than 8,000 eels in the loch, which is good since the European eel is actually critically endangered. But most of the eels found in Loch Ness are smaller than average, and the longest European eel ever measured was only about 4 feet long, or 1.2 meters.
An eel can’t stick its head out of the water like Nessie is supposed to do, but it does sometimes swim on its side close to the water’s surface, which could result in sightings of a string of many humps undulating through the wate... -
To donate to help victims of Hurricane Helena:
Day One Relief - direct donation link
World Central Kitchen - direct donation link
It's the big 400th episode! Let's have a good old-fashioned mystery episode! Thanks to Richard from NC for suggesting two of our animal mysteries today.
Further reading:
A 150-Year-Old Weird Ancient Animal Mystery, Solved
The Enigmatic Cinnamon Bird: A Mythical Tale of Spice and Splendor
First ever photograph of rare bird species New Britain Goshawk
Scientists stumbled onto toothy deep-sea "top predator," and named it after elite sumo wrestlers
Bryde's whales produce Biotwang calls, which occur seasonally in long-term acoustic recordings from the central and western Pacific
A stylophoran [drawing by Haplochromis - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=10946202]:
A cinnamon flycatcher, looking adorable [photo by By https://www.flickr.com/photos/neilorlandodiazmartinez/ - https://www.flickr.com/photos/neilorlandodiazmartinez/9728856384, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=30338634]:
The rediscovered New Britain goshawk, and the first photo ever taken of it, by Tom Vieras:
The mystery fish photo:
The yokozuna slickhead fish:
The Biotwang maker, Bryde's whale:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
We’ve made it to the big episode 400, and also to the end of September. That means monster month is coming up fast! To celebrate our 400th episode and the start of monster month, let’s have a good old-fashioned mysteries episode.
We’ll start with an ancient animal called a stylophoran, which first appears in the fossil record around 500 million years ago. It disappears from the fossil record around 300 million years ago, so it persisted for a long time before going extinct. But until recently, no one knew what the stylophoran looked like when it was alive, and what it could possibly be related to. It was just too weird.
That’s an issue with ancient fossils, especially ones from the Cambrian period. We talked about the Cambrian explosion in episode 69, which was when tiny marine life forms began to evolve into much larger, more elaborate animals as new ecological niches became available. In the fossil record it looks like it happened practically overnight, which is why it’s called the Cambrian explosion, but it took millions of years. Many of the animals that evolved 500 million years ago look very different from all animals alive today, as organisms evolved body plans and appendages that weren’t passed down to descendants.
As for stylophorans, the first fossils were discovered about 150 years ago. They’re tiny animals, only millimeters long, and over 100 species have been identified so far. The body is flattened and shaped sort of like a rectangle, but two of the rectangle’s corners actually extend up into little points, and growing from those two points are what look like two appendages. From the other side of the rectangle, the long flat side, is another appendage that looks like a tail. The tail has plates on it and blunt spikes that stick up, while the other two appendages look like they might be flexible like starfish arms.
Naturally, the first scientists to examine a stylophoran decided the tail was a tail and the flexible appendages were arm-like structures that helped it move around and find food. But half a billion years ago, there were no animals with tails. Tails developed much later, and are mainly a trait of vertebrates.
That led to some scientists questioning whether the stylophoran was an early precursor of vertebrates, or animals with some form of spinal cord. The spikes growing from the top of the tail actually look a little bit like primitive vertebrae, made of calcite plates. That led to the calcichordate hypothesis that suggested stylophorans gave rise to vertebrates.
Then, in 2014, -
Thanks to Anbo, Murilo, Clay, and Ezra for their suggestions this week! Let's learn about some bears!
Further reading:
Snack attack: Bears munch on ants and help plants grow
Extinct vegetarian cave bear diet mystery unravelled
Ancient brown bear genomes sheds light on Ice Age losses and survival
The sloth bear has shaggy ears and floppy lips [photo from this site]:
An absolute unit of a Kodiak bear in captivity [photo by S. Taheri - zoo, own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=1118252]:
A polar bear:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we’re revisiting a popular topic, bears! We’ll talk about some bears we’ve never covered before, with suggestions from Anbo, Clay, Ezra, and Murilo. We’ll even discuss a small bear mystery which has mostly been solved by science.
To start us off, Anbo wanted to learn about bears in general. We’ve had bear episodes before, but our last episode all about bears was way back in 2017, in episode 42. Some of our listeners weren’t even born back then, which makes me feel super old.
Bears live throughout much of the world today, but they evolved in North America around 38 million years ago. These ancestral bears were small, about the size of a raccoon, but they were successful. They spread into Asia via the land bridge Beringia, where they were even more successful than in North America, so successful that by around 30 million years ago, descendants of those earliest bear ancestors migrated from Asia back into North America. But it wasn’t until the Pleistocene around 2 ½ million years ago that bears really came into their own.
That’s because bears are megafauna, and megafauna evolved mainly as an adaptation to increasingly cold climates. As the ice ages advanced, a lot of animals grew larger so they could stay warm more easily. Predators also had to grow larger as their prey became larger, since if you want to hunt an animal the size of a bison or woolly rhinoceros, you’d better be pretty big and strong yourself.
Bears mostly weren’t hunting animals that big, though. Modern studies suggest that overall, bears are omnivores, not fully carnivorous. Bears eat a lot of plant material even if you don’t count the panda, which isn’t very closely related to other bears. Even when a bear does eat other animals, they’re not usually very big ones.
Let’s take Murilo’s suggestion as an example, the sloth bear. The sloth bear lives in India and is increasingly vulnerable due to habitat loss and poaching. It’s probably most closely related to the sun bear that we talked about in episode 234, which also lives in parts of South Asia. Both the sun bear and the sloth bear have long black hair and a white or yellowish V-shaped marking on the chest. The sloth bear’s hair is especially long on its neck and shoulders, like a mane, and its ears even have long hair.
The sloth bear stands around 3 feet high at the shoulder at most, or 91 cm, and a big male can be over 6 feet tall, or almost 2 meters, when he stands on his hind legs. This isn’t gigantic for bears in general, but it’s not small either. Scientists think the V-shaped marking on its chest warns tigers to leave the sloth bear alone, and tigers mostly do. If tigers think twice about attacking an animal, you know that animal has to be pretty tough.
The sloth bear has massive claws on big paws. The claws can measure 4 inches long, or 10 cm, although they’re not very sharp. The bear has an especially long muzzle but its teeth aren’t very large. Like most bears, it’s good at climbing trees and can run quite fast, and it swims well too. It even has webbed toes.
With all this in mind, what do you think the sloth bear eats? I’ll give you some more hints. It has loose, kind of flappy lips, especially the lower lip. It doesn’t have any teeth in the front of its upper jaw. It mainly uses its huge claws to dig. -
Thanks to Alexandra, Pranav, Eilee, Conner, and Joel for their suggestions this week!
Velella velella, or by-the-wind-sailor [photo from this page]:
Porpita porpita, or the blue button [photo from this page]:
Cricetus cricetus, or the European hamster, next to a golden hamster:
Nasua nasua, or the South American coati [photo from this page]:
Mola mola, or the ocean sunfish:
Quelea quelea, or the red-billed quelea [photo from this page]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we’re going to learn a little bit about scientific names, and along the way we’re going to learn about several animals. Thanks to Alexandra, Eilee, Conner, Joel, and Pranav for their suggestions!
Alexandra inspired this episode by suggesting two animals, the by-the-wind-sailor and the blue button. Both are marine invertebrates that look superficially like jellyfish, but they’re actually colonial organisms. That means that although they look like a single animal, they’re actually made up of lots of tiny animals that live together and function as one organism.
The blue button is closely related to the by-the-wind-sailor and both are related to siphonophores. Both the blue button and the by-the-wind-sailor spend most of the time near or on the ocean’s surface and have a gas-filled chamber that helps keep them afloat, with stinging tentacles that hang down into the water, but both are made up of a colony of tiny animals called hydroids. Different hydroids have different functions, and all work together to find tiny food that will benefit the entire colony.
The blue button gets its name because its float is round and flat like a button, and often blue or teal in color. It’s quite small, only a little over an inch across, or about 3 cm, and its tentacles are not much longer. The by-the-wind-sailor is a little larger than the blue button, with a blue sail-shaped float that’s only a few inches across, or maybe 7 cm, with stinging tentacles of about the same size. The stings of both organisms aren’t very strong and aren’t dangerous to humans, but they do hurt, so it’s a good idea not to touch one. Since both can be very common in warm ocean waters and they sometimes get blown ashore by the wind in large numbers, it can be hard to avoid them if you’re visiting the beach at the wrong time. They can still sting you if they’re dead, too.
The by-the-wind sailor has the scientific name of Velella velella while the blue button’s scientific name is Porpita porpita. The term for a scientific name that contains the same words is a repeating scientific name, also called a tautonym or tautonymous name, and that’s the subject of this episode.
A scientific name is something we mention a lot but if you’re not sure what it means, it can sound confusing. Every organism with a scientific name has been described by a scientist, meaning it’s been studied and placed somewhere in the great interconnected web of life. The system of giving organisms scientific names is called binomial nomenclature. The first word of the name indicates which genus the organism belongs to, while the second word indicates what species it is. These are called generic and specific names. Some organisms also have a third word in their scientific name which indicates its subspecies.
The reason scientists use a complicated naming system is to make it easier for other scientists to know exactly what organism is being discussed. For example, let’s say a scientist has been studying hamsters in the wild to learn more about them, and publishes a paper about her observations. If she just calls the animal a hamster, someone reading it might assume she was talking about the hamster found in their part of the world, when the paper is actually about a totally different, although closely related, hamster that lives somewhere else. And that brings us to Pranav’s suggestion, the European hamster, -
Thanks to Cosmo, William, and Silas for their fishy suggestions this week!
You have until Sept. 13, 2024 to back the enamel pin Kickstarter!
Further reading:
The Handfish Conservation Project
Researchers Look in Tank and See Promising Cluster of Near-Extinct Babies
The unique visual systems of deep sea fish
A red handfish:
Another red handfish. This one is named Hector:
The black dragon fish:
The white-edged freshwater whipray [photo by Doni Susanto]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we return to the vertebrate world, specifically some strange and colorful fishies. Thanks to William, Cosmo, and Silas for their suggestions!
We’ll start with Silas’s suggestion, the red handfish. We talked about it before back in episode 189, but it’s definitely time to revisit it. When we last discussed it, scientists estimated there were fewer than 100 red handfish left in the wild, meaning it was in imminent danger of extinction. Let’s find out how it’s doing now, four years later.
The handfish gets its name because its pectoral fins look like big flat hands. It spends most of its time on the sea floor, and it uses its hands to walk instead of swimming. It can swim, although it’s not a very strong swimmer, and anyway if you had great big hands you might choose to walk on them too. It doesn’t have a swim bladder, which helps most fish stay buoyant.
All species of handfish are small, only growing to about 6 inches long at most, or 15 cm. This is surprising considering the handfish is closely related to anglerfish, and some anglerfish can grow over 3 feet long, or about a meter.
As for the red handfish specifically, it generally only grows about 4 inches long at most, or 10 cm, and it once lived in shallow water around much of Australia. These days, it’s only found on two reefs southeast of Tasmania. Some populations are bright red while some are pink with red spots. It has a wide downturned mouth that makes it look like a grumpy red toad with big hands.
So how is the red handfish doing? Four years ago it was almost extinct in wild, with fewer than 100 individuals alive. These days the Handfish Conservation Project estimates that the wild population is probably about the same, although because the red handfish is so small and hides so well among sea grass, algae, and rocks that make up its home, it’s hard to get a good count of how many are really alive. It’s also under even more pressure than before as an overpopulation of urchins is overgrazing the plants where it lives, which may sound familiar to you if you listened to episode 395 a few weeks ago. But there is one fantastic change that gives conservationists hope that the red handfish won’t go extinct after all.
The red handfish is so endangered, and its remaining habitat is so small, that a few years ago scientists decided they needed to start a captive breeding program. But even though the fish did just fine in captivity, they didn’t breed at first. Then, in November 2023, one of the fish laid 21 eggs and all 21 hatched safely. Hopefully it won’t be long until the babies are old enough to release into the wild.
The red handfish is one of very few fish that hatch into tiny baby fish instead of into a larval form. Newly hatched babies are only about 5 mm long. Most fish colonize new habitats after they float around aimlessly as larvae, until they grow enough to metamorphose into adults. Since the red handfish doesn’t have this larval stage, and babies just walk around on the sea floor finding tiny worms and other food, it’s hard for the fish to expand its range. Hopefully, as the captive breeding program continues and more young fish are released into the wild, scientists can start releasing red handfish into areas where they used to live.
Next, William asked about the dragon fish. We’ve talked about a few dragonfish before, in episodes 193 and 231, -
Thanks to Joel and an anonymous listener for their suggestions this week!
Further reading:
Dieback and recovery in poplar and attack by hornet clearwing moth
The enormous and beautiful Atlas moth:
A male hairy tentacle moth without and with coremata extended [photos from this site]:
The hornet moth looks like a hornet but can't sting:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
Welcome to September, where we’re mere weeks away from Monster Month! Invertebrate August is over for another year, but what’s this? An episode about moths?! Hurrah for one extra invertebrate episode, because they don’t get enough attention on this podcast! Thanks to Joel and an anonymous listener for their suggestions.
First, a listener who wants to remain anonymous suggested that we talk about moths in general, and the Atlas moth in particular. I like the Atlas moth because you can catch it in Animal Crossing. It’s also beautiful and one of the largest moths in the entire world. Its wingspan can be well over 10 inches across, or about 27 cm, which is bigger than a lot of bird wingspans.
The Atlas moth’s wings are mostly cinnamon brown with darker and lighter spots. The upper wings have a curved sort of hook at the top that’s lighter in color and has an eyespot. It looks remarkably like a snake head, and in fact if a predator approaches, the moth will move its wings so that it looks like a snake is rearing its head back to strike.
Despite having such huge wings, atlas moths don’t fly very well. That’s okay because they only need to be able to fly for a few days, which they mostly do at night. They’re only looking for a mate, not food, because they don’t even have fully formed mouthparts. They don’t eat as adults. Like many moths, they mate, lay eggs, and die.
A few weeks later, the eggs hatch and the baby caterpillars emerge. The caterpillar is pale green with little spikes all over, and it eats plants until it grows to around 4 and a half inches long, or about 11 and a half cm. At that point it spins a cocoon attached to a twig, hidden from potential predators by dead leaves that the caterpillar incorporates into the cocoon’s outside.
The Atlas moth lives in forests in southern Asia, including China, India, Indonesia, and Malaysia, with a subspecies native to Japan. Its cocoons are sometimes collected to use for silk. The silk isn’t as high a quality as the domesticated silk moth’s, but it’s very strong and since the cocoons are so big, they produce lots of silk. Sometimes people will collect a cocoon after the moth has emerged and use it as a little purse.
Next, Joel suggested two interesting moths. The first is often called the hairy tentacle moth, which sounds absolutely horrifying. Its scientific name is Creatonotos gangis, and it lives in parts of Australia and southeast Asia.
The hairy tentacle moth is also called the Australian horror moth and other names that inspire fear and disgust. But why? The moth is really pretty. Its wings are pale brown and white with dark gray stripes in the middle, and it has a black spot on its head. The abdomen is usually red with black spots in a row. The wingspan is about 40 mm.
The issue comes with the way the male attracts a female. Inside his abdomen the male has four coremata, which are glands that emit pheromones. Pheromones are chemicals that other moths can detect, much like smells. When a male is ready to advertise for a mate, he perches on the edge of a leaf or somewhere similar and inflates the coremata so that they unfurl from inside the abdomen, like blowing up a balloon. Sometimes he only extends two of the coremata, sometimes all of them. Either way, the coremata are surprisingly large, sometimes longer than the entire abdomen. They’re dark gray with feathery hairs and they do actually look like hairy tentacles. They’re sometimes called hair pencils, but the term coremata is actually Greek for feath... -
Thanks to Sy and Finn for their suggestions this week!
Further reading:
Creeping Crinoids! Sea Lilies Crawl to Escape Predators, New Video Shows
New and Unusual Crinoid Discovered
Sea otters maintain remnants of healthy kelp forest amid sea urchin barrens
Sea urchins see with their feet
A sea lily [photo from this page]:
A feather star [still from a video posted on this page]:
Purple urchins [photo by James Maughn]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week as we bring invertebrate August to a close, we’re going to cover some animals suggested by Finn and Sy.
We’ll start with Sy’s suggestion, crinoids, also called feather stars or sea lilies depending on what body plan a particular species has. We talked about them in episode 79 but it’s definitely time to revisit them.
Crinoids are echinoderms, a really old phylum of animals. Fossils of ancient echinoderms date back to the Cambrian half a billion years ago and they’re still incredibly common throughout the world’s oceans.
Ancient crinoids had five arms the way many starfish do, which makes sense because crinoids are related to starfish. At some point each arm developed into two, so many crinoids have ten arms or even more, and many have arms that branch. The arms are used for feeding and have feathery appendages lined with sticky mucus that traps tiny bits of food floating in the water.
There are two big divisions of crinoids today, the feather stars and the sea lilies. Feather stars are more common and can swim around as adults if they want to, although most stick to crawling along the sea floor. They swim by waving their feathery arms. Sea lilies look like flowers as adults, with a slender stem-like structure with the small body and long feathery arms at the top. I specify that sea lilies have stems as adults because a lot of feather stars also have stems as juveniles, but when they reach maturity they become free-swimming.
Even though the sea lily looks like a plant, and some species even have root-like filaments that help it anchor itself to the sea floor or to rocks, it’s still an animal. For one thing, it can uproot itself and move to a better location if it wants to, crawling with its arms and pulling its stem behind it, which is not something a plant can do except in cartoons. If a predator attacks it, the sea lily will even shed its stem completely so it can crawl away much faster. Since echinoderms in general are really good at regenerating parts of the body, losing its stem isn’t a big deal.
The biggest sea lilies today are deep-sea species, but even they only grow a stem up to about three feet long at most, or about a meter. This wasn’t the case in the ancient past, though. The longest crinoid stem fossil ever discovered was 130 feet long, or 40 meters.
Crinoids filter food particles from the water that flows through the feathery arms. Even though they look like feathers or petals, a crinoid’s arms are actually arms. They have tiny tube feet on them that act sort of like fingers to help the crinoid hold onto pieces of food, and to do a better job of holding the food, the tube feet are covered with a sticky mucus. The mouth is in the middle of the arms on the top of the body.
Crinoids absorb oxygen directly from the water. Its body contains a system of chambers and pores that are full of water, and by contracting special muscles, the crinoid moves water around in its body to transport nutrients and oxygen and to collect waste material.
Crinoids are closely related to starfish, sea cucumbers, sand dollars, and sea urchins, which brings us to Finn’s suggestion. Finn suggested urchins, which are also echinoderms. In fact, at the end of episode 79 I mentioned that one day I’d do an episode about urchins, and it only took me six years to get here!
Many urchins look like living pincushions because they’re covered in spines. That’s where the name urchin comes from, -
Thanks to Anbo and Siya for suggesting the mantis shrimp this week!
The Kickstarter for some animal-themed enamel pins is still going on!
Further reading:
Rolling with the punches: How mantis shrimp defend against high-speed strikes
The magnificent peacock mantis shrimp [picture by Cédric Péneau, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=117431670]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
As invertebrate August continues, this week we have a topic suggested by Anbo and Siya. They both wanted to learn about the mantis shrimp!
The mantis shrimp, which is properly called a stomatopod, is a crustacean that looks sort of like a lobster without the bulky front end, or a really big crayfish. Despite its name, it’s not a shrimp although it is related to shrimps, but it’s more closely related to lobsters and crabs. It can grow as much as 18 inches long, or 46 cm, but most are about half that size. Most are brown but there are hundreds of different species and some are various brighter colors like pink, blue, orange, red, or bright green, or a rainbow of colors and patterns.
There are two things almost everyone knows about the mantis shrimp. One, it can punch so hard with its claws that it breaks aquarium glass, and two, it has 12 to 16 types of photoreceptor cells compared to 3 that humans have, and therefore it must be able to see colors humans can’t possibly imagine.
One of those things is right, but one is wrong, or at least partially wrong. We’ll discuss both in a minute, but first let’s learn the basics about these fascinating animals.
The mantis shrimp lives in shallow water and spends most of its time in a burrow that it digs either in the sea floor or in crevices in rocks or coral, which it enlarges if necessary. Some species will dig elaborate tunnel systems while others just wedge themselves into any old crack that will hide them. It molts its exoskeleton periodically as it grows, like other crustaceans, and after that it either has to expand its burrow or move to a larger one. Most species live in tropical or subtropical areas, but some prefer more temperate waters.
It has eight pairs of legs, which includes three pairs of walking legs, four pairs with claws that help it grasp items, and its front pair, which are hinged and look a little like the front legs of a praying mantis. That’s where the “mantis” in mantis shrimp comes from, although of course it has lots of other names worldwide. In some places it’s called the thumb splitter.
The mantis shrimp has two eyes on stalks that move independently. Its brain extends into the eye stalks, and the section of the brain in the eye stalks, called the reniform body, is what processes vision. This allows it to process a lot of visual information very quickly. Reniform bodies have also been identified in the brains of some other crustaceans, including shrimp, crayfish, and some crabs. Scientists also think that the eyes themselves do a lot of visual processing before that information gets to the reniform body or the brain at all. In other words, part of the reason the mantis shrimp’s eyes are so complicated and so unusual compared to other animals’ eyes is because each eye is sort of a tiny additional brain that mainly processes color.
The typical human eye can only sense three wavelengths of light, which correspond to red, green, and blue. The mantis shrimp has twelve different photoreceptors instead of three, meaning it can sense twelve wavelengths of light, and some species have even more photoreceptors. But while our brains are really good at synthesizing the three wavelengths of light we can see, combining them so that we see incredibly fine gradations of color in between red, green, and blue, the mantis shrimp doesn’t process color the same way we do. So while its eyes can sense colors we can’t, its brain doesn’t seem to do anything with the color information. -
Thanks to Siya, Zachary, Khalil, and Eilee for their suggestions this week!
The enamel pin Kickstarter goes live on Wednesday, August 14, 2024!!
Further reading:
How spiders breathe under water: Spider’s diving bell performs like gill extracting oxygen from water
Aggressive spiders are quick at making accurate decisions, better at hunting unpredictable preys
Into the Spider-Verse: A young biologist shares her love for eight-legged creatures
A New Genus of Prodidominae Cave Spider from a Paleoburrow and Ferruginous Caves in Brazil
The diving bell spider [photo from this paper]:
Jumping spiders are incredibly cute, even the ones that eat other spiders [photo taken from this excellent site]:
The spoor spider's web looks like a cloven hoofprint in the sand [photo by JMK - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=39988887]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
I’m excited this week, because on Wednesday my little Kickstarter to fund getting more enamel pins made goes live, and also we’re talking about some weird and fascinating spiders! Thanks to Siya, Zachary, Khalil, and Eilee for their spider suggestions!
A lot of people are afraid of spiders, but don’t worry. All the spiders in this episode are small and completely harmless unless you are a bug. Also, they probably live very far away from you. Personally, I think most spiders are cute.
Let’s start with a spider suggested by Siya, who pointed out that we don’t actually have very many episodes about spiders. Siya suggested we learn about the diving bell spider, a tiny, remarkable animal that lives in parts of Europe and Asia.
The diving bell spider gets its name because it mostly lives underwater but still needs to breathe air, so it brings air with it into the water. A diving bell made by humans is a structure shaped sort of like a big bell that can be lowered straight down into the water on a cable. If the diving bell doesn’t tip to one side or another, the air inside it stays inside and allows a human diver to take breaths without coming to the surface. A diving bell made by spiders is made of silk but is shaped sort of the same, with an entrance at the bottom. The spider builds its bell among water plants to anchor it and keep it hidden. The spider brings air from the surface to replenish the supply of air inside the bell.
The spider does this by surfacing briefly. Its belly and legs are covered with tiny water-repellent hairs, and after surfacing the hairs trap air, so that when it dives back into the water it’s covered with little silvery bubbles. It swims down to its diving bell and rubs the bubbles off its body, which rise into the bell and are trapped there by the closely woven silk. Then it goes back to the surface for more air.
Once the bell is full of air, the spider only needs to replenish the air supply about once a day under normal circumstances. That’s because the bell itself acts as a sort of external gill. It’s able to absorb oxygen from the water quite efficiently, but it still loses volume slowly because nitrogen from the air diffuses into the water. If not for that, the spider probably wouldn’t need to come to the surface at all.
The diving bell is the spider’s home, especially for the female. Unlike most spiders, the female diving bell spider is much smaller than the male and she hunts differently. The male is an active hunter, swimming quickly to catch tiny animals like mosquito larvae, so he’s large and strong but only has a small diving bell. The female spends most of her time in her diving bell and only swims out to catch animals that come too close, or occasionally to replenish the air in her bell.
When the spider leaves its diving bell to hunt, air bubbles remain trapped on its abdomen, which allows it to breathe while it’s hunting too. Then it can dart back to its bell to get more air or hide if it needs to. -
Thanks to Kari and Joel for their suggestions this week! You can find Kari Lavelle's excellent book Butt or Face? Volume 2: Revenge of the Butts at any bookstore.
Our Kickstarter for some enamel pins goes live in just over a week if you're interested!
Further reading:
Jellyfish size might influence their nutritional value
History of Taiji Mantis
Glowing octocorals have been around for at least 540 million years
The moon jellyfish [photo by Alexander Vasenin - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=32753304]:
A Chinese mantis [photo by Ashley Bradford, taken from this site]:
Also a Chinese mantis:
A type of octocoral:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
It’s finally Invertebrate August! We have some great episodes coming up this month, so let’s get started. Thanks to Kari and Joel for their suggestions this week!
First, we’ll start with an invertebrate from Kari Lavelle’s latest book, Butt or Face? Volume 2: Revenge of the Butts! It’s a sequel to the hilarious and really interesting book we talked about last summer. Kari kindly sent me a copy of the book and it’s just as good as the first one. Don’t worry, I won’t spoil the answer of whether the picture in the book is of an animal’s butt or face, but let’s talk about the moon jellyfish.
We’ve talked about jellyfish in several previous episodes, most recently in episode 343. Moon jellyfish is the term for jellies in the genus Aurelia, all of which look so identical that it takes close study by an expert, or a genetic test, to determine which species is which. We’re going to talk about a specific species in this episode, Aurelia aurita, but most of what we’ll learn about it also applies to the other moon jelly species.
Aurelia aurita lives in temperate, shallow water and is often found in harbors and close to shore. It’s mostly transparent and can grow up to 16 inches across, or 40 cm, although most are smaller. It’s sometimes called the saucer jelly because when its bell is open, it’s shaped sort of like a saucer or shallow bowl, if the bowl was upside down in the water with pinkish-white internal organs inside and short stinging tentacles. That’s most bowls, I think.
Unlike a lot of jellyfish, the moon jelly doesn’t have long tentacles that hang down from the middle of the bell. Instead, its tentacles are short and thin and line the edges of the bell. There are hundreds of them, but while the tentacles do have stinging cells, they’re not very strong. If you were to pet a moon jelly, you probably wouldn’t even feel the stings but you’d probably get sticky digestive mucus on your hands from the tentacles. The mucus is sticky to trap tiny pieces of food, which can include everything from fish eggs and various types of larvae to microscopic animals called diatoms and rotifers.
The moon jellyfish can survive in water with low oxygen, and in fact it prefers low oxygen water. Since most larger marine animals that live near the surface need a lot of oxygen to survive, the moon jelly can safely find its tiny food in low-oxygen areas without worrying too much about predators. Actually the moon jellyfish doesn’t worry about much of anything, because like other jellies, technically it doesn’t have a brain, just a nerve net.
Speaking of predators, for a long time scientists have wondered why anything bothers to eat jellies. They’re mostly water, which makes them easy for other animals to digest, but they contain almost no nutritional value. A study published in March 2023 determined that the bigger the jellyfish is, the more fatty acids its body contains, and fatty acids are an important nutrient. The main difference between a little jelly and a big jelly (besides size) is what they eat, so scientists think the bigger jellies are eating prey that contain more fatty acids, which slowly accumulate in the jelly’s body too.
Next, -
Follow the enamel pin Kickstarter here!
Let's learn about some snakes this week! Thanks to Eilee, BlueTheChickenWing, and Richard from NC for their suggestions.
Further Reading:
Snake Island's Venomous Vipers Find a New Home in Sao Paulo
'Rarest Snake' in the U.S. Hatches at Tennessee Zoo
The golden lancehead [picture from first article linked above]:
The Martinique lancehead/fer-de-lance:
The Louisiana pine snake, and a pine cone:
Show Transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
After today, the next four weeks will be all about invertebrates, or animals without a backbone, because it’s almost Invertebrate August! But this week let’s learn about some animals that are basically nothing but backbones, snakes! Thanks to Eilee, BlueTheChickenWing, and Richard from NC for their suggestions!
Also, if you like enamel pins even slightly as much as I do, I’m starting a Kickstarter in a few weeks to make some more. These will be bigger than the ones I made a few years ago and will include an aye-aye. Where else are you going to get an aye-aye enamel pin? There’s a link in the show notes if you want to sign up for an email reminder when the campaign goes live in mid-August. https://www.kickstarter.com/projects/kateshaw/familiar-friends-enamel-pins
Anyway, let’s start with Snake Island, suggested by Eilee. Snake Island is off the coast of Brazil in South America, and it’s quite small, only about 106 acres total, or 43 hectares. It’s hilly and a little over half of it is covered with a temperate rainforest, while the rest is grassy or just bare rocks. No one lives there these days and it’s a protected area that only scientists are allowed to visit, with the exception of members of the Brazilian navy who occasionally stop by to maintain the lighthouse that keeps ships from smashing into the rocky coast. Lots of birds live on the island or visit there, but other than that it’s mostly just snakes.
Specifically, the critically endangered golden lancehead pit viper lives on Snake Island and nowhere else in the world. It can grow nearly four feet long, or 118 cm, and is pale gold or golden-brown in color with darker splotches. It’s also incredibly venomous—but no one has ever been bitten by one as far as we know. If somehow you were bitten by one, it probably wouldn’t be a pleasant situation but you also probably wouldn’t die. That’s mainly because the golden lancehead’s venom is adapted to kill birds and reptiles, not mammals. And that’s because there are no mammals living on Snake Island.
The golden lancehead spends most of its time in trees or bushes, hunting for birds. It mainly eats two particular species of small bird that live on the island, although it will also eat other birds, lizards, and invertebrates like insects. Some reports say it will even eat smaller golden lanceheads. There’s another snake that lives on the island, Sauvage’s snail-eater, and the golden lancehead might occasionally snack on one of those. The snail-eater is also present on mainland Brazil and isn’t venomous. You can probably guess that it mainly eats snails. It’s small and thin, lives in trees, and is brownish-yellow with darker stripes and splotches.
The issue with Snake Island and its snakes is that there isn’t that much land available for the snakes to live on, and the forest has been damaged by human activity. Big chunks of forest were cleared by fire when people decided to try growing bananas on the island, which didn’t work very well. No one lives there now, but poachers do occasionally visit the island to catch snakes for the illegal wildlife trade. The golden lancehead is starting to show signs of inbreeding and disease as a result. As if that wasn’t bad enough, because the island is so close to the coast of Brazil, and mainland Brazil has its own problems with deforestation, fewer birds are migrating through the area every year. -
Thanks to Jaxon and Lorenzo for their suggestions this week!
Further reading:
Rock-wallaby bite size 'packs a punch'
Tiny Australian wallaby the last living link to extinct giant kangaroos
Extraordinary Fossil of Giant Short-Faced Kangaroo Found in Australia
Wiwaxia corrugata - The Burgess Shale
The nabarlek:
The banded hare-wallaby:
Wiwaxia was a little less cute than wallabies are:
An artist's rendition of what Wiwaxia might have looked like when alive [picture from last page linked above]:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
Every so often I get an animal suggestion that I’m positive we’ve already covered, but then I’m flabbergasted when it turns out we haven’t. That’s the case for the animals we’ll learn about this episode, with thanks to Jaxon and Lorenzo!
A while ago, Jaxon left us a nice review and suggested we talk about wallabies. I was CONVINCED we’d talked about the wallaby repeatedly, but I think I was thinking about the wombat. We’ve hardly ever mentioned the wallaby, and it’s such a great animal!
The wallaby is a marsupial that basically looks like a miniature kangaroo, although some species grow pretty large. The resemblance makes sense because kangaroos and wallabies are closely related, but everything else about the wallaby family tree is confusing. That’s because there are a lot of animals called wallabies that aren’t actually the same type of animal. “Wallaby” is just a catchall term used by people to describe any animal that looks kind of like a miniature kangaroo.
Wallabies are native to Australia and New Guinea, but various species have been introduced to other places where they’re invasive, including New Zealand, France, England, Scotland, and Hawaii. Most of these non-native populations happened by accident when pets or zoo animals escaped into the wild, but some were introduced on purpose by people who didn’t know they were causing damage to the local ecosystems.
One thing everyone knows about kangaroos, which is also true for wallabies, is that they hop instead of running. Their hind legs are extremely strong with big feet, and in fact the name of the family they share, Macropodidae, means big feet. So, you know, Bigfoot exists but maybe doesn’t look like most people think. The animal hops by leaning forward and jumping, with its big hind feet leaving the ground at about the same time, and landing at the same time too before it bounces again. Its big tail helps it balance. But there’s a lot more to this hopping than you might think.
While the wallaby or kangaroo has strong leg muscles, what’s even more important is that it has very strong, very elastic tendons in its legs. These basically act like massively strong rubber bands. When you stretch a rubber band, it stores energy that it releases when you let go of it and it snaps back and whips you in the thumb and you wonder why you did that because it hurt. The tendons in the wallaby’s legs store energy when it hops, and when it lands, the energy releases and helps bounce the animal right back into the next hop. Once it gets going, its muscles are only doing a fraction of the work to keep it hopping at high speed. Even better for the animal, a lot of its breathing is regulated by its movements when it’s hopping, so it always has plenty of oxygen to power its body while moving fast. When it lands after a bounce, the impact pushes its breath out of its lungs, but the action of bringing its legs forward helps suck fresh air in. It’s an incredibly efficient way to move, and allows the animal to travel long distances to find food and water without spending a lot of energy.
Wallabies eat plants, and naturally the bigger species can eat bigger, tougher plants than smaller species. The exception is the dwarf rock-wallaby, according to a study published in March of 2024. There are over a dozen species of rock-wallaby, -
It's our annual updates episode! Thanks to Kelsey and Torin for the extra information about ultraviolet light, and thanks to Caleb for suggesting we learn more about the dingo!
Further reading:
At Least 125 Species of Mammals Glow under Ultraviolet Light, New Study Reveals
DNA has revealed the origin of this giant ‘mystery’ gecko
Bootlace Worm: Earth’s Longest Animal Produces Powerful Toxin
Non-stop flight: 4,200 km transatlantic flight of the Painted Lady butterfly mapped
Gigantopithecus Went Extinct between 295,000 and 215,000 Years Ago, New Study Says
First-Ever Terror Bird Footprints Discovered
Last surviving woolly mammoths were inbred but not doomed to extinction
Australian Dingoes Are Early Offshoot of Modern Breed Dogs, Study Shows
A (badly) stuffed lava bear:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This week we have our annual updates episode, and we’ll also learn about a mystery animal called the lava bear! As usual, a reminder that I don’t try to update everything we’ve ever talked about. That would be impossible. I just pick new information that is especially interesting.
After our episode about animals and ultraviolet light, I got a great email from Kelsey and Torin with some information I didn’t know. I got permission to quote the email, which I think you’ll find really interesting too:
“You said humans can’t see UV light, which is true, however humans can detect UV light via neuropsin (a non-visual photoreceptor in the retina). These detectors allow the body to be signaled that it’s time to do things like make sex-steroid hormones, neurotransmitters, etc. (Spending too much time indoors results in non-optimal hormone levels, lowered neurotransmitter production, etc.)
“Humans also have melanopsin detectors in the retina and skin. Melanopsin detectors respond to blue light. Artificial light (LEDs, flourescents, etc) after dark entering the eye or shining on the skin is sensed by these proteins as mid-day daylight. This results in an immediate drop in melatonin production when it should be increasing getting closer to bedtime.”
And that’s why you shouldn’t look at your phone at night, which I am super bad about doing.
Our first update is related to ultraviolet light. A study published in October of 2023 examined hundreds of mammals to see if any part of their bodies glowed in ultraviolet light, called fluorescence. More than 125 of them did! It was more common in nocturnal animals that lived on land or in trees, and light-colored fur and skin was more likely to fluoresce than darker fur or skin. The white stripes of a mountain zebra, for example, fluoresce while the black stripes don’t.
The study was only carried out on animals that were already dead, many of them taxidermied. To rule out that the fluorescence had something to do with chemicals used in taxidermy, they also tested specimens that had been flash-frozen after dying, and the results were the same. The study concluded that ultraviolet fluorescence is actually really common in mammals, we just didn’t know because we can’t see it. The glow is typically faint and may appear pink, green, or blue. Some other animals that fluoresce include bats, cats, flying squirrels, wombats, koalas, Tasmanian devils, polar bears, armadillos, red foxes, and even the dwarf spinner dolphin.
In episode 20 we talked about Delcourt’s giant gecko, which is only known from a single museum specimen donated in the 19th century. In 1979 a herpetologist named Alain Delcourt, working in the Marseilles Natural History Museum in France, noticed a big taxidermied lizard in storage and wondered what it was. It wasn’t labeled and he didn’t recognize it, surprising since it was the biggest gecko he’d ever seen—two feet long, or about 60 cm. He sent photos to several reptile experts and they didn’t know what it was either. Finally the specimen was examined and in 1986 it was described as a new species. -
Further reading:
Audubon's Bird of Washington: Unraveling the fraud that launched The Birds of America
The Mystery of the Missing John James Audubon Self-Portrait
Washington's eagle, as painted by Audubon:
The tiny detail in Audubon's golden eagle painting that is supposed to be a self-portrait:
The golden eagle painting as it was published. Note that there's no tiny figure in the lower left-hand corner:
Show transcript:
Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.
This past weekend I was out of town, or to be completely honest I will have been out of town, because I’m getting this episode ready well in advance. Since July 4 was only a few days ago, or will have been only a few days ago, and July 4 is Independence Day in the United States of America, I thought it might be fun to talk about a very American bird, Washington’s eagle.
We talked about it before way back in episode 17, and I updated that information for the Beyond Bigfoot & Nessie book for its own chapter. When I was researching birds for episode 381 I revisited the topic briefly and realized it’s so interesting that I should just turn it into a full episode.
We only have two known species of eagle in North America, the bald eagle and the North American golden eagle. Both have wingspans that can reach more than 8 feet, or 2.4 meters, and both are relatively common throughout most of North America. But we might have a third eagle, or had one only a few hundred years ago. We might even have a depiction of one by the most famous bird artist in the world, James Audubon.
In February 1814, Audubon was traveling on a boat on the upper Mississippi River when he spotted a big eagle he didn’t recognize. A Canadian fur dealer who was with him said it was a rare eagle that he’d only ever seen around the Great Lakes before, called the great eagle. Audubon was familiar with bald eagles and golden eagles, but he was convinced the “great eagle” was something else.
Audubon made four more sightings over the next few years, including at close range in Kentucky where he was able to watch a pair with a nest and two babies. Two years after that he spotted an adult eagle at a farm near Henderson, Kentucky. Some pigs had just been slaughtered and the eagle was looking for scraps. Audubon shot the bird and took it to a friend who lived nearby, an experienced hunter, and both men examined the body carefully.
According to the notes Audubon made at the time, the bird was a male with a wingspan of 10.2 feet, or just over 3 meters. Since female eagles are generally larger than males, that means this 10-foot wingspan was likely on the smaller side of average for the species. It was dark brown on its upper body, a lighter cinnamon brown underneath, and had a dark bill and yellow legs.
Audubon named the bird Washington’s eagle and used the specimen as a model for a life-sized painting. Audubon was meticulous about details and size, using a double-grid method to make sure his bird paintings were exact. This was long before photography.
So we have a detailed painting and first-hand notes from James Audubon himself about an eagle that…doesn’t appear to exist.
Audubon painted a few birds that went extinct afterwards, including the ivory-billed woodpecker and the passenger pigeon, along with less well-known birds like Bachman’s warbler and the Carolina parakeet. He also made some mistakes. Many people think Washington’s eagle is another mistake and was just an immature bald eagle, which it resembles.
But here’s the problem. Audubon wasn’t always truthful. He painted some birds that he never saw but claimed he did, because another bird illustrator had painted them first. Once he claimed he went hunting with Daniel Boone in Kentucky in 1810, but at that time Boone would have been in his 70s and was living several states away.
Audubon also claimed that he discovered a little bird called Lincoln’s sparrow, but this wasn’t the case. - Vis mere
