Episode 425 Rabbits!

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Thanks to Alyx and Richard from NC for their suggestions this week! Let’s learn about rabbits!

Further reading:

Why your pet rabbit is more docile than its wild relative

FOUND: Small enigmatic rabbit with black tail lost to science for more than 120 years rediscovered hopping around mountain range in Mexico

The Omiltemi cottontail rabbit, as caught on a camera trap [photo taken from second article linked above]:

Show transcript:

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

This week we’re going to talk about bunnies, and also learn about how a wild animal differs from its domesticated counterpart. Thanks to Alyx for suggesting this excellent topic. Thanks also to Richard from NC who alerted me to a rediscovered rabbit we’ll discuss too.

Thanks for all the well wishes in the last few weeks about my surgery. It went just fine and all I have now is a cool-looking new scar, although I was seriously hoarse for about a week. It’s pretty weather here in East Tennessee and officially it’s spring in the northern hemisphere, so let’s talk about some springtime bunnies!

Collectively rabbits and hares are called leporids after their family, Leporidae. Leporids are famous for hopping instead of walking, and they’re able to do so because their hind legs are longer than their front legs and have specialized ankle joints. Ancestors of leporids developed this ankle as much as 53 million years ago, but their legs were much shorter so they probably ran instead of hopped. Hares have longer legs than rabbits and can run faster as a result, but both rabbits and hares are known for their ability to bound at high speeds. When a rabbit or hare runs, it pushes off from the ground with the tips of its long hind toes, and its toes are connected with webbed skin so they can’t spread apart. If the toes did spread apart, they would be more likely to get injured. Rabbits and hares also don’t have paw pads like dogs and cats do. The bottom of its foot is covered with dense, coarse fur that protects the toes from injury. Its long claws help it get a good purchase on the ground so its feet won’t slip.

Leporids eat plants, including grass, weeds, twigs, and bark. Animals that eat grass and other tough plants have specialized digestive systems so they can extract as many nutrients from the plants as possible. Many animals swallow the plants, digest them for a while, then bring up cuds of plants and water to chew more thoroughly. Rabbits and hares don’t chew their cud in that way, but they do have a system that allows them to twice-digest the plants they eat.

After a leporid eats some plants, the plant pieces go into the stomach, naturally, and then travel into the first part of the large intestine, called the cecum. The cecum separates the softer parts of the plants from the harder, less digestible parts. The hard parts are compressed into hard pellets that the rabbit poops out. But the soft parts of the plants, which are most nutritious, develop into softer pellets. These are called cecotropes, and as soon as the rabbit poops out the cecotropes, it immediately eats them again. This allows the digestive system to get a second round to extract more nutrients from the plants.

Hares aren’t domesticated, but rabbits have probably been domesticated many times in different places over the last several thousand years, first for food and fur, and then as pets. The domesticated rabbit we have today is descended from the European rabbit, also called the cony. If other species of rabbit were ever domesticated, we don’t have record of it. The rabbit has also been introduced into the wild in places it has no business to be, like Australia, where it’s an invasive species. You know where else the European rabbit has been introduced? The British Isles. It’s native to mainland Europe, not England, Scotland, Ireland, Wales, and smaller islands nearby. Historians think the rabbit was introduced to England soon after the year 1066, but it got really common a few hundred years later.

We discussed domestication way back in episode 106, mostly in relation to dogs. An interesting thing happens with domestication. Certain physical traits come along with the behavioral traits of reduced aggression and willingness to treat humans as surrogate parents. In the case of dogs, these often include a puppy-like appearance, including floppy ears, curled tail, smaller adult size, and a rounder head with smaller jaws. White patches of fur start to show up too.

This is true in rabbits as well as dogs. Because humans wanted to breed rabbits that weren’t scared of people, domesticated rabbits are less anxious and aggressive in general than their wild counterparts. When traits like white patches, lop ears, and a more rounded face appeared in the domesticated population, people would keep those rabbits to breed because they’re extra cute, which has led to over three hundred different breeds recognized today by rabbit enthusiasts.

Because domesticated rabbits are calmer and more trusting than wild rabbits, they can’t survive long in the wild. A domesticated rabbit doesn’t know how to escape from predators or avoid cars, and it’s not used to cold weather. If you decide to adopt a bunny, make sure you do research ahead of time to know what to expect, and as with most animals it’s best to adopt two so they won’t be lonely. Rabbits are social animals and need a rabbit friend. There are even pet rescues that specialize in rabbits who need homes.

We talked about giant rabbits in episode 115, and the tiny volcano rabbit in episode 356, so let’s finish this episode with a medium-sized rabbit called the Omiltemi cottontail. Cottontail rabbits are native to the Americas and most have fluffy white fur on the underside of their tails. The Omiltemi cottontail doesn’t have any white fur at all, and is reddish-brown and black in color with some lighter gray on its face. It’s large for a wild rabbit, about 18 inches long, or 45 cm, although it’s actually smaller than other rabbits that live in the area. It lives only in Mexico, specifically in a single part of the Sierra Madre del Sur mountain range, in what is now the Omiltemi Ecological State Park.

It was first described in 1904 and then reportedly wasn’t seen again, although the local people knew all about it. Even though it lives in a protected area, poaching is still a big problem. When an expedition to find the rabbit got underway in 2019, local hunters provided pelts to the scientists when they asked about the rabbit, since they didn’t know they weren’t supposed to kill the local rabbits. They certainly didn’t know they had an incredibly rare species of rabbit living in their back yards.

The team used camera traps, drone surveys, and the knowledge of local people to find and identify the Omiltemi cottontail. It turns out that the rabbit is mostly nocturnal and prefers higher elevations, which made it harder to find. We still don’t know how many there are left, but now that scientists are certain that it’s not extinct, it can be better protected.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. 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 424 Old-Timey Giant Snakes

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Show transcript:

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

Recently I read about a giant snake supposedly seen in Tennessee in 1908. The story seemed a little suspicious so I dug into it, and it got a lot more complicated than I expected.

On July 25, 1908, the St. Louis (Missouri) Globe-Democrat ran an article about a giant snake in Loudon, Tennessee. Loudon is a town half an hour’s drive away from Knoxville in East Tennessee, although it took longer to get there from Knoxville in 1908. According to the article, the snake was “at least twenty-five feet in length, eight inches in diameter and twenty-four inches in circumference.”

The longest snake ever reliably measured is a reticulated python named Medusa, who was measured as 25 feet 2 inches long in 2011, or 7.67 meters. Medusa holds the world record for the longest snake in captivity. Reticulated pythons are constrictors, which are non-venomous snakes who kill their prey by squeezing them until blood flow is shut off to the organs, causing cardiac arrest and death. As a result, they’re incredibly strong snakes. The reticulated python is native to southern Asia and not likely to be found running loose in East Tennessee even today, and certainly not in 1908.

The famous Boa constrictor and other snakes in the genus Boa are all native to Central and South America, while the closely related anaconda is from tropical South America. These snakes are also constrictors.

The anaconda is rumored to grow over 30 feet long, or 9 meters, although the longest specimen ever reliably measured was 17 feet long, or 5.2 meters. Since snake skin is stretchy, though, preserved skins of huge size are often provided as proof of snakes much longer than the known maximum. While the anaconda isn’t as long as the reticulated python, it’s much bulkier, so a 25-foot anaconda would be much heavier and larger around than a 25-foot reticulated python.

The 1908 article claims that the snake “has been seen off and on for the last twenty-eight years, but not until this summer has it caused any serious alarm.” I don’t know about you, but even as someone who likes animals and thinks snakes are neat, if I saw a 25-foot snake I would be a little bit alarmed even if it wasn’t doing anything. The article then describes how the snake had knocked down a fence while climbing over it and that it had taken a lamb. One man even managed to shoot the snake, although only with “small shot,” and the article claims that the snake, “in a frenzy from the pain, tore up saplings in getting away.”

The article finishes by reporting that women and children were barricaded in their homes while men organized a posse to hunt down the giant snake, which was rumored to live in a cave overlooking the river.

The same article ran in various newspapers around the country for months, but there was no follow-up to let readers know if the snake had been found. But the story didn’t appear in any Tennessee newspapers.

The only 1908 article about a giant snake in Tennessee that appears in a Tennessee newspaper is from August 21. The Chattanooga, Tennessee Daily Times reported that a blacksnake “fully six feet long and two inches in diameter” had been spotted eating young pigeons above the Birmingham railway station. A police officer shot and killed it, but its body couldn’t be recovered from the steep hillside above the tunnel.

“Blacksnake” is a term used for two snakes that are common throughout the southern United States: the eastern black kingsnake and the North American racer. Both are black in color and can grow more than 6 feet long, or 1.8 meters. Both are non-venomous and eat small animals like mice, frogs, and lizards, while the kingsnake also sometimes eats other snakes.

The longest snake found in Tennessee, which also lives throughout much of eastern North America, is the gray ratsnake, which is frequently 6 feet long and sometimes longer. One unverified report of a captive snake 8 feet 10 inches long, or almost 2.5 meters, comes from Tennessee. It’s a mixture of dark and light gray with a lighter belly. It’s non-venomous and is actually a constrictor, although it’s not dangerous to humans. If it feels threatened, it will sometimes pretend to strike and rattle the tip of its tail against dead leaves or whatever else might be underneath it, which produces a buzzing sound that mimics a rattlesnake’s rattle. You’re not fooling anyone, gray ratsnake.

The eastern racer will also vibrate its tail against leaves to imitate a rattlesnake’s rattle, but the eastern racer is such a fast-moving snake that it doesn’t usually need to convince potential predators it’s dangerous. It just runs away. Despite its name of Coluber constrictor, it’s not actually a constrictor, although it will pin an animal to the ground with its body until it can swallow it whole. It and the gray ratsnake can both climb trees and will eat bird eggs and young birds when they find them.

There is another article about a giant snake in a Tennessee newspaper from 1908. The Chattanooga Star reported on August 20 that a 12-foot, or 3.6 meter, rattlesnake was attacked by a boar when it tried to enter a hog pen. The farmer managed to shoot the snake, which had 29 rattles. The snake was referred to as “Big Jim” in the area. But that story was supposed to have happened in Sullivan, Indiana, not in Tennessee.

But Indiana newspapers don’t run this account. A July 22, 1908 article in the Indianapolis News reports that a rattlesnake with 26 rattles was killed in Nashville, Indiana, but that snake was not quite six feet long, or 1.8 meters.

The “Big Jim” account does appear in one Indiana newspaper, the Hamilton County Times from August 21, 1908. But that article is headlined “Some Hoosier ‘Nature Fakes’” and says Big Jim was first spotted in the neighboring state of Illinois but had been discovered attacking a farmer’s chickens in Sullivan County, Indiana. This must be the same as Sullivan, Indiana reported in the Tennessee paper. But Big Jim was only ten feet long in the Indiana story, or 3 meters, and wasn’t killed. The article says the local farmers were organizing to hunt it down, but then goes on to talk about some other stories of huge snakes and a giant fish. It seems clear that the Indiana article is meant to be amusing, not factual.

The largest rattlesnake species is the eastern diamondback rattler, and the largest one ever reliably measured was 7.8 feet long, or 2.4 meters. That’s big, but it’s not Big Jim big. The eastern diamondback also doesn’t live anywhere near Indiana or Illinois. It’s native to the southeastern United States, especially along the coast.

Newspaper reporters weren’t always scrupulous in the olden days, sometimes making up stories to fill space and entertain the reader. Stories of huge snakes are so common in old newspaper reports that the term “snake story” was once used interchangeably with “fish story” to indicate an animal of improbable size that was supposedly spotted or killed, but without any proof.

In 1935, the Statesville (North Carolina) Record and Landmark ran an article titled “Giant Snake Story Proves To Be Hoax.” No kidding! In this case, though, the story was about a snake skin 16 feet long, or nearly 5 meters, which was supposed to be from a rattlesnake killed in a local swamp. The article revealed that the two men who claimed to have shot the rattlesnake had later confessed the skin was from a python, and had been sent to one of the men by a relative in South America. At least that one was from a real snake.

Thanks for your support, and thanks for listening!

Episode 423: Pack Rats and Busy Mice

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Further reading:

Mouse filmed moving items in man’s shed in Bristol

The pack rat:

Show transcript:

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

This week I’m sharing a Patreon episode from last year because I have surgery scheduled. Don’t worry, it’s minor thyroid surgery and I’ll be fine, but my doctor said that a side effect might be hoarseness while I recover. Rather than risk sounding like an old frog, and to allow myself lots of time to rest afterwards, I’ve scheduled Patreon episodes for this week and next week.

At the beginning of this year, in early January 2024, you may have heard about a man in Wales who had an interesting visitor to his work shed. Rodney Holbrook is 75 years old and a retired postal worker, and at the end of 2023 he started noticing something weird. Things in his work shed kept being moved, and not in a way that suggested another person was getting in.

Initially Rodney noticed that some bird food had been moved into an old pair of shoes. This wasn’t just a one-time thing that would suggest an accident, like maybe Rodney had absent-mindedly decided to store the bird food in his shoes, or maybe it just fell there. The bird food kept ending up in the shoes.

Other things kept getting moved too. Small items that Rodney had left out while making and repairing things at his work bench kept getting put into a box, like tools and nuts and bolts. It happened almost every night.

Fortunately, Rodney is also a wildlife photographer, and he just happened to have a night vision camera. He set it up in the shed to find out what on earth was going on.

A mouse was going on, that’s what was going on. This actually wasn’t a huge surprise to Rodney, because years before, in 2019, a friend of his had had the same thing happen.

His friend was Steve Mckears who lived near Bristol, England. Steve kept crushed peanuts in a tub to use as bird food, but he started to notice other things mixed in with the peanuts. First it was just one screw, then it was lots more things that he’d left around his shed. He couldn’t figure out a solution, because he always locked his shed at night.

As Steve said at the time, “I was worried. I’m 72 and you hear of things going wrong with 72-year-old gentlemen in the mind.” Fortunately, Steve’s friend Rodney set up a camera and proved that there was nothing wrong with Steve’s mind or with the shed’s lock. It was just a mouse who was tidying up.

The question is why are these mice tidying up someone else’s shed? Don’t the mice have sheds of their own to clean up? It’s probable that the mice are actually living in the sheds and are wondering why some humans keep barging in every day and making a mess.

Rodents of all kinds do tend to tidy up as part of the foraging and nesting process. Sometimes that means moving debris so the animal can find important items more easily, sometimes it means bringing items back to its nest. House mice and rats will steal small items from humans to make nests, like socks and facecloths. Some rodents are attracted to shiny things and will stash them away or even bury them.

One animal, the pack rat, is so famous for storing items that we call a person who likes to collect things a pack rat. The pack rat lives throughout much of North and Central America and is related to mice and rats. It’s bigger than a mouse but smaller than most rats, and some species have furry tails like ground squirrels. It builds a den out of whatever materials are available where it lives, and its den is complex and usually well hidden. Desert species like to build under a cactus, while others live in cliffs or among rocks, in abandoned buildings or sometimes non-abandoned buildings, under bushes, in the tops of trees, or even in the entrances to caves. The den can be quite large and contains numerous rooms used for food storage, sleeping, and storing all the interesting things the pack rat finds while foraging.

A pack rat constructs a debris pile to hide its den, referred to as a midden. “Midden” is an old-fashioned word used to describe a place where household waste used to be thrown. Archaeologists love middens because you can learn a lot about people by the things they throw away, and other scientists love pack rat middens for the same reason. Some pack rat middens have been discovered preserved for 50,000 years, which has allowed scientists to learn a lot about what plants were growing in the area at the time. Since the middens also contain the pack rat’s fecal pellets, the scientists can also learn a lot about what the rat was eating, how big it was, and so forth.

Pack rats especially like shiny objects and will steal from people. In 2017 when historians were restoring an old home in Charleston, South Carolina dating back to 1808, they discovered several old pack rat middens in the walls of the kitchen. The middens contained buttons, marbles, sewing pins, and even some scraps of paper, including bits of newspaper with a readable date from November 1833. But some of the other bits of paper were torn from a writing primer, a book for people learning how to read or write. That’s not much of a surprise until you remember that this was the early 19th century, that the house was owned by a slave trader, and that the kitchen in particular would have been staffed by enslaved people, who were not supposed to learn how to read. Thanks to the pack rats, we know that at least one person was secretly learning how to read and write. I just hope the rats didn’t do too much damage to their book.

The pack rat is also sometimes called a trader rat, because it can only carry one thing at a time. If it’s carrying an acorn home and it chances upon a shiny gold ring, it will drop the acorn and carry the ring home. But you wanted an acorn, didn’t you, instead of that ring?

As for mice tidying up, we don’t really know why they do it, but it’s probably actually quite common. It just happens at night when people aren’t around, and in the morning they don’t know why all the nails have been moved into the box of nails, but hey, isn’t that handy? It reminds me of the stories of little house spirits called brownies, which were supposed to work at night cleaning and tidying. When the family woke up the next morning, the house or workshop was, ahem, squeaky clean, and all the family had to do was leave out a little cake or cream every night for the brownie.

Thanks for your support, and thanks for listening!

Episode 422: Two Tiny, Tiny Animals

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Thanks to Tim and Mia who suggested one of this week’s animals!

Further reading:

Genomic insights into the evolutionary origin of Myxozoa within Cnidaria

A tardigrade, photo taken with an electron microscope because these little guys are incredibly tiny:

Show transcript:

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

This week we’re going to talk about two microscopic or almost microscopic animals, one suggested by Mia and Tim, the other one I just learned about myself.

We’ll start with Mia and Tim’s suggestion, the water bear, also known as the tardigrade. We’ve talked about it before but there’s always more to learn about an animal.

The water bear isn’t a bear at all but a tiny eight-legged animal that barely ever grows larger than 1.5 millimeters. Some species are microscopic. There are about 1,300 known species of water bear and they all look pretty similar. It looks for all the world like a plump eight-legged stuffed animal made out of couch upholstery. It uses six of its fat little legs for walking and the hind two to cling to the moss and other plant material where it lives. Each leg has four to eight long hooked claws. It has a tubular mouth that looks a little like a pig’s snout.

An extremophile is an organism adapted to live in a particular environment that’s considered extreme, like undersea volcanic vents or inside rocks deep below the ocean floor. Tardigrades aren’t technically extremophiles, but they are incredibly tough. Researchers have found tardigrades in environments such as the gloppy ooze at the bottom of the ocean and the icy peaks of the Himalayas. It can survive massive amounts of radiation, dehydration for up to five years, pressures even more intense than at the bottom of the Mariana Trench, temperatures as low as -450 Fahrenheit, or -270 Celsius, heat up to 300 degrees Fahrenheit, or 150 Celsius, and even outer space. It’s survived on Earth for at least half a billion years. Mostly, though, it just lives in moss.

Not every tardigrade is able to do everything we just talked about. They’re tough, but they’re not invulnerable, and different species of tardigrade are good at withstanding different extreme environments. Many species can withstand incredible heat, but only for half an hour or less. Long-term temperature increases, even if only a little warmer than what it’s used to, can cause the tardigrade to die.

Most species of tardigrade eat plant material or bacteria, but a few eat smaller species of tardigrade. It has no lungs since it just absorbs air directly into its body by gas exchange. It has a teeny brain, teeny eyes, and teeny sensory bristles on its body. Its legs have no joints. Its tubular mouth contains tube-like structures called stylets that are secreted from glands on either side of the mouth. Every time the tardigrade molts its cuticle, or body covering, it loses the stylets too and has to regrow them. In some species, the only time the tardigrade poops is when it molts. The poop is left behind in the molted cuticle.

The tardigrade’s success is largely due to its ability to suspend its metabolism, during which time the water in its body is replaced with a type of protein that protects its cells from damage. It retracts its legs and rearranges its internal organs so it can curl up into a teeny barrel shape, at which point it’s called a tun. It needs a moist environment, and if its environment dries out too much, the water bear will automatically go into this suspended state, called cryptobiosis.

Tests in 2007 and 2011 that exposed tardigrades to outer space led to some speculation that tardigrades might actually be from outer space, and that they, or organisms that gave rise to them, might have hitched a ride on a comet or some other heavenly body and ended up on earth. But this isn’t actually the case, since genetic studies show that tardigrades fit neatly into what we know of animal development and evolution. In other words, tardigrades are weird, but they’re Earth weird.

Our other tiny animal today is one that lacks pretty much everything animals usually have. Myxozoa are parasites that can’t live outside of the host’s body, a condition called obligate parasitism. They’re found in both freshwater and ocean water animals but evolved from an animal similar to a jellyfish that would have just swum around happily in the ocean. Now they’re microscopic parasites with the smallest genomes of any animals studied. Most only measure 300 micrometers at most, or 1/3 of a millimeter, although the largest known grows a humongous 2 mm long.

Different myxozoa have different life cycles, some of them complex. Because they’re so small, we naturally don’t know that much about them, and there are undoubtedly a whole lot of species that haven’t been discovered by science. They’re so numerous, and so different from other animals, that they’ve been placed into their own subphylum, classified in the Phylum Cnidaria. Cnidarians include jellyfish, corals, sea anemones, and many other aquatic invertebrates that show radial symmetry–but not comb jellies which have their own phylum.

In general, this is how a myxozoan spreads to a new host. A myxozoan secretes tiny capsules called myxospores that contain polar filaments. The myxopores are eaten by worms, at which point the capsule opens and the polar filaments uncoil and attach to the worm’s gut, where it develops into a sporoplasm and eventually detaches from the worm. The sporoplasm floats around in the water until it touches a fish, especially a fish’s gills, at which point it digs into the fish’s body and continues to develop.

When scientists identified the first myxozoans, they were classified as protozoans, single-celled animals. Many protozoans are parasitic. But as genetic testing became more refined and easier to do, and some myxozoans had their DNA sequenced, it became obvious that they were something else. Scientists just weren’t sure what. Finally scientists realized that they were similar genetically to jellyfish and their close relations, although they estimate it’s been about 600 million years since they shared a common ancestor.

Many myxozoans no longer have genes that allow communication between cells, multicellular development, body coordination, or even respiration in some species. Most are only a few cells in size and the most complex cell is the one that contains what’s called a polar capsule. This probably developed from its ancestor’s nematocysts, which are the cells that sting you if you touch a jellyfish, which is why you should never touch a jellyfish no matter how pretty it is.

Most myxozoa infect fish, but they’ve also been discovered in other animals. This includes a few frogs, turtles, aquatic birds, and octopuses. But they’ve also been discovered in two mammals, both of them shrews. Even though we already know about more than 2,000 species of myxozoa, scientists think there are probably hundreds, if not thousands more, but no one’s noticed them yet because they’re so small.

If you remember the Dr. Seuss book Horton Hears a Who, consider that the Whos might have actually been tardigrades. But probably not myxozoa, which wouldn’t have been able to build a Who city.

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 421: Australian Animals

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Thanks to Nora, Holly, Stephen, and Aila for their suggestions this week!

Further reading:

How ‘bin chickens’ learnt to wash poisonous cane toads

Monkeys in Australia? Revisiting a Forgotten Furry Mystery Down Under

The Australian white ibis:

The greater glider looks like a toy:

The thorny devil is very pointy:

Show transcript:

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

This week we’re going to talk about some animals native to Australia, which is Nora’s suggestion. We’ll learn about animals suggested by Holly, Stephen, and Aila, along with a mystery animal reported in the 1930s in northern Australia.

Australia isn’t currently connected to any other landmass and hasn’t been for about 50 million years. That means that most animals on the continent have been evolving separately for a very long time. While in other parts of the world placental mammals took over many ecological niches, marsupials are still the dominant mammal type in Australia. Most marsupial females give birth to tiny, helpless babies that then continue their development outside of her body, usually in a pouch.

But let’s start the episode not with a marsupial but with a bird. Stephen suggested the Australian white ibis, a beautiful bird that doesn’t deserve its nickname of bin chicken.

The white ibis is related to ibises from other parts of the world, but it’s native to Australia, and is especially common in eastern, northern, and southwestern Australia. It’s a large, social bird that likes to gather in flocks. Its body is mostly white with a short tail, long black legs, and a black head. Like other ibises, the adult bird’s head is bare of feathers. It also has a long, down-curved black bill that it uses to dig in the mud for crayfish and other small animals. When the bird spreads its magnificent black-tipped wings, it displays a stripe of featherless skin that’s bright red.

The Australian white ibis prefers marshy areas where it can eat as many frogs, crayfish, mussels, and other animals as it can catch. But at some point around 50 years ago, the birds started moving into more urban areas. They discovered that humans throw out a lot of perfectly good food, and before long they started to become a nuisance to people who had never encountered raccoons and didn’t know they should clamp those trash barrels closed really securely.

But no matter how annoying the Australian white ibis can be to people, it’s been really helpful in another way. In the 1930s, sugarcane plantation owners wanted to control beetles and other pests that eat sugarcane plants, so they released a bunch of cane toads in some of their fields in Queensland. But the cane toads didn’t do any good eating the beetles. Instead, they ate native animals and spread like wildfire. Since the toads are toxic, nothing could stop them, and there are now an estimated two billion cane toads living in Australia. But the Australian white ibis eventually figured out how to deal with cane toads.

The ibis will grab a cane toad, then whip it around and throw it into the air so that the toad secretes its toxins in hopes that the bird will leave it alone. Then the ibis will wash the toad in water or wipe it in wet grass, which washes away the toxins. Then the ibis eats the toad. Goodbye, toad!

Our next Australian animal is one suggested by Holly, the greater glider. When I saw the picture Holly sent, I was convinced it wasn’t a real animal but a toy plushie, but that’s just what the greater glider looks like. It’s incredibly cute!

The greater glider lives in eastern Australia, and as you might guess from its name, it is the largest of the three glider species found in Australia, and it can glide from tree to tree on flaps of skin between its front and back legs. Until 2020 scientists thought there was only one species of glider with local variations in size and coat color, but it turns out those differences are significant enough that it’s been split into three separate but closely related species.

The greater glider is nocturnal and only eats plant material, mostly from eucalyptus trees. It has a long fluffy tail, longer than the rest of its body is. Its tail can be as much as 21 inches long, or 53 cm, while its body and head together can measure as much as 17 inches long, or 43 cm. It has dense, plush fur, a small head with big round ears, black eyes, and a little pinkish nose, and it superficially looks like a big flying squirrel. But the greater glider isn’t a rodent. It’s a marsupial, closely related to the ringtail possum. Some individuals have dark gray or black fur and some have lighter gray or brown fur, but all greater gliders have cream-colored fur on their tummies.

The greater glider’s gliding membranes, also called patagia, are connected at what we can refer to as their elbows and ankles. It uses its long tail as a rudder and it’s very good at gliding from tree to tree. It almost never comes down to the ground if it can avoid it. When it glides, it folds its front legs so its little fists are under its chin and its elbows are stuck out, which stretches the membranes taut.

Aila suggested we learn more about the thorny devil, an Australian reptile we talked about way back in episode 97. It’s a spiky lizard that grows to around 8 inches long, or 20 cm. In warm weather its blotchy brown and yellow coloring is paler than in colder weather, when it turns darker. It can also turn orangey, reddish, or gray to blend in to the background soil. Its color changes slowly over the course of the day as the temperature changes. It also tends to turn darker if something threatens it.

It has a thick spiny tail that it usually holds curved upward, which makes it look kind of like a stick. It moves slowly and jerkily, rocking back and forth on its legs, then surging forward a couple of steps. Researchers think this may confuse predators. It certainly looks confusing.

As if that wasn’t enough, the thorny devil has a false head on the back of its neck. It’s basically a big bump with two spikes sticking out of its sides. When something threatens the lizard, it ducks its head between its forelegs, which makes the bump on its neck look like a little head. But all its spines make it a painful mouthful for a predator. If something does try to swallow it, the thorny devil can puff itself up to make it even harder to swallow, like many toads do. It does this by inflating its chest with air.

The thorny devil eats ants, specifically various species of tiny black ants found only in Australia. It has a sticky tongue to lick them up. This is very similar to the horned lizard of North America, also called the horny toad even though it’s not a toad, which we talked about most recently in episode 376. But despite their similarities in looks, behavior, and diet, the horned lizard and the thorny devil aren’t closely related. It’s just yet another example of convergent evolution.

Now, let’s finish with a strange report from the 1930s about a colony of hundreds, if not thousands, of monkeys in Australia. Australia doesn’t have very many native placental mammals, and no monkeys. But several Australian newspapers reported in 1932 that a party of gold prospectors encountered the monkeys in northern Australia, specifically Cape York Peninsula. The monkeys were reportedly gathered in one area to eat a huge crop of red nuts, and they appeared to be large monkeys that weighed up to 30 lbs, or 13 kg. Another gold prospector said in follow-up articles that he too had seen the monkeys and even shot a few of them, although he hadn’t saved any part of the bodies.

Newspaper hoaxes were pretty common back in the day, but by the 1930s things had mostly settled down and papers were more interested in imparting actual news instead of making it up. Cape York Peninsula was quite remote at the time, with rivers, rainforests, and savannas where a lot of animals unknown to science probably still live. But not monkeys!

One thing to remember is that at the end of the 19th century, it was a fad to release animals from one area into another. That’s how the European starling was introduced to North America, where it has become incredibly invasive. In the early 1890s, a group of people released a hundred starlings into New York City’s Central Park, because they wanted all the birds mentioned in Shakespeare’s writings to be present in the United States. This fad included Australia, where colonizers tried to release all sorts of animals. Most of the animals didn’t survive long, and we don’t have any records of monkeys being released, but it’s possible that someone just did it for fun and didn’t tell anyone.

Another suggestion is that the prospectors saw tree kangaroos and thought they were monkeys, even though tree kangaroos don’t actually look like monkeys. They look like little kangaroos that live in trees, not to mention they’re mostly nocturnal. Besides, the local Aboriginal people reportedly told the prospectors about the monkeys, and they would have identified tree kangaroos easily if that’s what they were. No other native Australian animal known to live in the area resembles a monkey either.

Zoologist Karl Shuker suggests the monkeys might have been macaques native to New Guinea. New Guinea isn’t all that far away from Australia, and macaques were often kept as pets too. It would have been pretty easy for someone to buy a bunch of macaques, import them on a ship, and release them into the wilderness. Or the macaques might have gotten there on their own, rafting to Australia on fallen trees washed out to sea during storms.

If there really were monkeys in Australia 90 years ago, of course, the big question is: are they still there?

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 420: The Sea Bunny

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Thanks to Sam for suggesting this week’s topic, the sea bunny!

My plush sea bunny, with one of my cats, Dracula, who does not like it:

Show transcript:

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

This week we’re going to revisit an animal we haven’t talked about in a few years! Thanks to Sam for suggesting it, and for sending a whole list of questions after listening to episode 215. Episode 215 was about the cutest invertebrates, and we talked about a lot of them. This week it’s all about the sea bunny.

Before we answer Sam’s questions, let’s go over what we learned in episode 215, in case you haven’t listened to it since it came out in March of 2021. The sea bunny, or sea rabbit, is a type of nudribranch [noodi-bronk] that lives along the coastline of the Indo-Pacific Ocean, especially in tropical waters. Nudibranchs are a type of mollusk that are sometimes called sea slugs. Many are brightly colored with beautiful patterns.

Compared to some sea slugs, the sea bunny is a little on the plain side. It’s usually orange or yellow, sometimes white or even green, with tiny brown or black speckles. It looks fuzzy because it’s covered in little protuberances that it uses to sense the world around it, as well as longer, thinner fibers called spicules. It also has two larger black-tipped protuberances that look for all the world like little bunny ears, although they’re actually chemoreceptors called rhinophores. It has a flower-shaped structure on its rear end that looks kind of like a bunny tail, but it’s actually gills. It really is amazing how much the sea bunny actually resembles a little white bunny with dark speckles.

Like other nudibranchs, the sea bunny is a hermaphrodite, which means it produces both eggs and sperm, although it can’t fertilize its own eggs. When it finds a potential mate, they both perform a little courtship dance to decide if they like each other. After mating, both lay strings of eggs in a spiral pattern. The eggs hatch into larvae that are free-swimming, although the adults crawl along the ocean floor looking for food. Some nudibranch larvae have small coiled shells like snails, which they shed when they metamorphose into an adult, but the sea bunny hatches into a teeny-tiny miniature sea bunny.

One of Sam’s questions was what the sea bunny eats. It mainly eats sea sponges. The toxins present in many sponges don’t bother the sea bunny. Instead, the sea bunny absorbs the sponge’s toxins and keeps them in its body. I don’t usually bother with Reddit posts while researching episodes, but I saw one where people were discussing how toxic the sea bunny is. Someone pointed out that small as they are, it’s not a good idea to pick up a sea bunny because they are so toxic, and someone replied, “That’s good for them, because I’m going to assume they taste like Marshmallows.”

That brings us to Sam’s next question, does anything eat the sea bunny? That’s mainly a no, because they are so incredibly toxic. An animal the size of a big shark or something like that probably wouldn’t be affected by the sea bunny’s toxins, but it also wouldn’t bother with such a tiny snack. A fish or other animal small enough for the sea bunny to seem like a meal probably wouldn’t survive its toxins.

Sam also wants to know if the sea bunny travels in groups, and that doesn’t seem to be the case. It’s a mostly solitary animal most of the time. If it did gather in a group, say if a bunch of sea bunnies were munching on the same sponge at the same time, maybe we could call it a fluffle of sea bunnies, or a school of sea bunnies.

Sam also wants a better idea of how small the sea bunny is. It’s easy enough to say, oh, it’s a little less than an inch, or around 2 ½ cm, but most of us have a hard time picturing that. So here’s a comparison that will help you visualize it. If you have an ordinary paperclip, not one of the jumbo ones, it’s usually around 2.5 cm long, maybe just a bit bigger. So a big sea bunny is just barely the length of an ordinary paperclip.

Sam’s last question is one of the most important ones, and I bet at least some of our listeners are wondering the same thing. Can you keep a sea bunny as a pet?

The answer is no, sorry! Aside from the sea bunny being really toxic and not safe for your other aquarium pets or you, it would need care that’s hard for a home aquarium keeper to provide. Some experienced saltwater aquarium keepers do have some types of sea slugs, but not typically sea bunnies, not even big professional aquariums.

Fortunately for all of us, sea bunnies are popular enough these days that you can get a sea bunny plushie. I know because I have one—and I found it just two days ago as this episode goes live! I was looking through the half-priced Valentine’s Day stuff on February 15 when I found a stuffy that looked just like a sea bunny. I picked it up and sure enough, it was a sea bunny, and it was on sale! There’s a picture of it in the show notes. It’s a lot bigger than a real life sea bunny, but it’s also not toxic.

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 419: The Elephant Seal

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Thanks to Charlotte, Clay, and Richard from NC for their suggestions this week!

Further reading:

Seal whiskers, the secret weapon for hunting

Elephant seals drift off to sleep while diving far below the ocean surface

Scientists Discover Remains of Antarctic Elephant Seal in Indiana River

The elephant seal and its proboscis:

The bunyip carving:

Show transcript:

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

This week we have an animal suggested by three different listeners, Charlotte, Clay, and Richard from NC. So, by popular demand, let’s learn about the elephant seal, including some elephant seal mysteries.

The elephant seal gets its name because it’s big, grayish-brown, and wrinkled. Adult male elephant seals even have a proboscis, although it’s not anywhere near as long as an elephant’s trunk. It’s basically an enlarged and elongated nose that allows the animal to make loud roaring noises to intimidate other males. This is what that sounds like:

[elephant seal roars]

There are two species of elephant seal, the northern and southern. The southern elephant seal is larger on average while the northern male has a larger proboscis on average. We talked about elephant seals briefly in episode 155, about sexual dimorphism, because males and females are much different in size. A big male southern elephant seal can grow up to 20 feet long, or 6 meters, and can weigh about 9,000 lbs, or 4,000 kg. Females are about half that length and much lighter in weight. A big male northern elephant seal can grow up to 16 feet long, or almost 5 meters, and weigh around 5,500 lbs, or 2,500 kg, while females are much smaller.

There are many reasons why male elephant seals are bigger than females, but it’s mainly because the males spend a lot of energy fighting each other. The bigger and stronger a male is, the more likely he is to win a fight and the more likely it is that other males won’t bother to challenge him. Meanwhile, females are smaller so they need less food.

The elephant seal has thick fur that helps keep it warm, but it also has a layer of blubber like whales do. The blubber also helps make the seal streamlined so it can swim faster. Since the elephant seal spends most of its life in the water, and it does a lot of diving, it needs to be as streamlined as possible. It eats animals like fish, squid, and octopuses, but it especially likes sharks and rays.

Since a lot of the elephant seal’s favorite prey lives on or near the ocean floor, it has to dive to find it. The deepest recorded dive of an elephant seal was almost 5,700 feet, or about 1,700 meters. That’s just over a mile deep, the deepest dive made by a mammal that isn’t a whale. The elephant seal can hold its breath for well over an hour and a half. To conserve energy and maximize its time, quite often an elephant seal will actually sleep while it’s swimming downward, since a really deep dive can take a long time to descend. It might only wake up when it bumps into the sea floor, but sometimes it’s sleeping so soundly that it will just lie there at the bottom of the ocean and continue to sleep. I guess that’s why the sea floor is sometimes called the seabed.

Because the elephant seal hunts for food where there’s not much light, it often can’t rely on its vision to find its prey. Instead, it has really good hearing underwater, and it has whiskers on its upper lip that are extremely sensitive, with more nerve fibers in each whisker than in any other mammal studied. Its whiskers can sense tiny movements of water that indicate an animal moving around nearby.

Once a year, the elephant seal molts and new fur grows in, but unlike most mammals it doesn’t just lose its fur. The outer layer of its skin peels off too. It takes a lot longer for its fur to regrow because blubber doesn’t contain any blood vessels. New blood vessels have to grow around the blubber to supply the skin with extra nutrients, and during that time the seal can’t spend time in the water or it will get too cold. It stays on land during molting, cuddled up with its friends so they can all stay warmer.

It can take a month to complete the molt, and the seals don’t eat the whole time. The males also don’t eat during mating season and the females don’t eat once their pups are born, not until the pup is a month old and doesn’t need its mother constantly. Elephant seals are adapted to be able to fast for long periods, but they do lose a lot of weight and have to eat plenty of extra food afterwards to regain it.

The elephant seal is well adapted to cold. The southern elephant seal lives in the southern ocean, around Antarctica, the southern tip of Patagonia, and south of New Zealand. The northern elephant seal lives in the eastern Pacific Ocean, off the coast of Canada and Alaska. Sometimes they roam farther, though, into warmer waters, and sometimes an elephant seal will investigate a river mouth and end up traveling far inland in the river. But sometimes a seal will make a really, really long journey.

About 1,260 years ago, one particular southern elephant seal started swimming north. It swam from the Southern Ocean along the South American coast, crossed the equator, and just kept swimming. It swam into the Gulf of Mexico and eventually came to the mouth of the Mississippi River. It swam up the mighty Mississippi and into a tributary river, and eventually it ended up in what is now Indiana, where it died.

We know all this because in 1965, construction workers found a jawbone near the Wabash River and donated it to the Field Museum of Natural History in Chicago. It wasn’t properly studied until decades later except to test its age. In 2020, a team of three scientists examined what was left of the jawbone after destructive radiometric testing in the 1970s, and they were shocked to realize it came from a southern elephant seal.

There are a lot of questions associated with the discovery. Why did the seal keep swimming? Was it lost and confused, and thought it was swimming back to its home? Was it just a ramblin’ seal, tryin’ to make a livin’ and doin’ the best it could feel? There’s no way to know, but there is a clue about what happened to it at the end. There are marks on the jawbone that might be cut marks.

At the time, over 1,500 years ago, that part of North America was inhabited by the Mississippian culture, a vast empire and the ancestor of many of the modern indigenous North American peoples. This was the culture who made giant earth mounds that still exist today in parts of North America, and when they were still being used, the mounds had grand buildings on top. Scientists aren’t sure if fishers or hunters spotted the elephant seal and killed it, or if someone found it already dead and decided to not let perfectly good meat go to waste. There’s even a theory that the animal didn’t swim to North America but that its skull was brought there by traders and at some point it ended up in the river.

The two elephant seal species do look very similar, and the scientists didn’t have the full original jawbone to study, so they also suggest it might actually have been a northern elephant seal. For a northern elephant seal to travel to Indiana without human help would be just as hard or even harder than a southern elephant seal, because there is no easy water passage from the Pacific coast of North America to Indiana. The seal would actually have to travel through the Arctic Ocean to the North Atlantic, then swim south to the Gulf of Mexico or the Gulf of St. Lawrence.

There is a big possibility that at least some stories of river monsters from the olden days were actually elephant seals that swam so far upstream in a river that the people who saw it didn’t know what the animal was. Even today, when many of us carry around tiny computers in our pockets that allow us to access all of humanity’s knowledge and also make phone calls, seeing an elephant seal in a place where it doesn’t belong would be terrifying.

We think that’s what happened long ago in Victoria in Australia. We talked about it in episode 351, in our episode about the bunyip. An Aboriginal sacred site near Ararat, Victoria once had the outline of a bunyip carved into the ground and the turf removed from within the figure. Every year the local indigenous people would gather to re-carve the figure so it wouldn’t become overgrown, because it symbolized an important event. At that spot, two brothers had been attacked by a bunyip. It killed one of the men and the other speared the bunyip and killed it. When he brought his family and others back to retrieve his brother’s body, they traced around the bunyip’s body.

The bunyip carving was 26 feet long, or 8 meters. Unfortunately it’s long gone, since eventually the last Aborigine who was part of the ritual died sometime in the 1850s and the site was fenced off for cattle grazing. But we have a drawing of the geoglyph from 1867. It’s generally taken to be a two-legged sea serpent type monster with a small head and a relatively short, thick tail. Some people think it represents a bird like an emu.

But if you turn it around, with the small head being the end of a tail, and the blunt tail being a head, suddenly it makes sense. It’s the shape of a seal.

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 418: Animals Discovered in 2024

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This week we take a look at some of the many animals that were discovered last year!

Further reading:

‘Blob-Headed’ Catfish among New Species Discovered in Peru

New Species of Dwarf Deer Discovered in Peru

Hylomys macarong, the vampire hedgehog

Hairy giant tarantula: The monster among mini tarantulas with ‘feather duster’ legs

Woods Hole Oceanographic Institution and partners discover new ocean predator in the Atacama Trench

Never-before-seen vampire squid species discovered in twilight zone of South China

The blob headed catfish [photo by Robinson Olivera/Conservation International]:

A new mini tarantula [photo by David Ortiz]:

Show transcript:

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

This week is the 8th year anniversary of this podcast, so thanks for listening! It’s also our annual discoveries episode, where we’ll learn about a few animals that were discovered last year–in this case, in 2024.

Let’s start in Peru, a country in western South America. A 2022 survey of organisms living in the Alto Mayo region was published at the very end of 2024, revealing at least 27 new species and potentially more that are still being studied. One of those new species is a fish called the blob headed catfish.

The new fish has been placed in the bristlemouth armored catfish genus, but as you can probably guess from its name, it has a big blobby head and face. Scientists have no idea why it has a blob head. It lives in mountain streams and that’s about all we know about it right now.

Another animal found in the same survey is a new mouse. It lives in swampy forests and is semi-aquatic, including having webbed toes. It’s dark gray in color and is probably closely related to the Peruvian fish-eating rat, which is mostly brown in color and was only described in 2020.

Another new species from Peru is a type of small deer, called a pudu, that has been named Pudella carlae. It’s one of those “hidden in plain sight” discoveries, because until 2024 it was thought to be the same as the northern pudu that also lives in Ecuador and Colombia. The new deer is only 15 inches tall, or 38 cm, and is dark brownish-orange in color with black legs and face. It only lives in Peru, mostly in high elevations. It’s also the first deer species discovered in the 21st century, although hopefully not the last.

While we’re talking about mammal discoveries, we have to talk about the vampire hedgehog just because of its name. It was actually described at the very end of 2023, but it’s such an interesting animal that we’ll say it’s a 2024 discovery.

The vampire hedgehog was actually discovered a whole lot earlier than 2023, but no one noticed it was new to science for a long time. A small team of researchers studying soft-furred hedgehogs decided to collect DNA samples from all the museum specimens they could find. One of the specimens was in the archives of the Smithsonian National Museum of Natural History, collected in 1961 but never studied. When the scientists compared its DNA to the other specimens they’d found, it didn’t match up. Not only that, a closer look showed that it had fangs. Naturally, they named it the vampire hedgehog and went searching for living ones.

The vampire hedgehog lives in parts of Vietnam and is a member of the soft-furred hedgehogs, also called gymnures, hairy hedgehogs, or moonrats. Instead of spines, moonrats have bristly fur and long noses that make them look like shrews, but hairless tails that make them look like rats. They’re not rodents but are closely related to other hedgehogs. They eat pretty much anything but especially like to eat meat. This includes mice and frogs, along with various invertebrates.

As for the vampire hedgehog’s fangs, both males and females have them, but males have bigger fangs. Scientists don’t know yet what the hedgehogs use their fangs for. It could be they help the animals keep a better hold on wiggly prey, but it could be the hedgehogs just think big fangs look good on other hedgehogs so they’re one way the animals decide on a mate.

Just a few weeks ago we talked about the biggest tarantula in the world, the goliath birdeater, but did you know that there are tiny tarantulas too? The genus Trichopelma contains miniature tarantulas with body lengths measured in millimeters, and a new one was described in 2024 from western Cuba. But the great thing is, this tiny tarantula is the largest of the two dozen species known. Of the four specimens found so far, the largest body length is 11.2 millimeters—a veritable giant among miniature tarantulas!

The new species has been named Trichopelma grande, and the males, at least, have been discovered in trap-door burrows in the ground. No female specimens have been observed yet. Ground-dwelling tarantulas usually have a lot less hair on their legs, while tarantulas that live in trees are the ones with especially hairy legs, but T. grande is ground-dwelling but has very hairy legs. Or at least the males do. We don’t know about females yet.

Now let’s talk about some ocean animals, and we have to go back to Peru for our first one. The Atacama Trench is also called the Peru-Chile Trench because it’s about 100 miles, or 160 km, off the coast of both countries. At this spot a continental plate in the ocean is pushing underneath the South American plate, and it’s incredibly deep as a result. It’s been measured as 26,460 feet below the ocean’s surface, or 8,065 meters. That’s five miles deep!

Not a lot of animals live near the bottom, where the water pressure is intense and there’s not much to eat, but little crustaceans called amphipods are fairly common in the trench. Amphipods are common animals throughout the world’s oceans and freshwater, with almost 10,000 species discovered so far. There’s even a terrestrial amphipod called the sandhopper. Amphipods look a little bit like tiny shrimp, although there are some giant species. Giant in this case means 13 inches long, or 34 cm, but most are like the miniature tarantulas and are measured in millimeters.

In 2023 a new amphipod was discovered near the bottom of the Atacama Trench, and it was described in 2024 as a new species in its own genus. It grows just over an inch and a half long, or almost 4 cm, and appears white because of its lack of pigment. And most interesting of all, it’s a predator that catches and eats other species of amphipod.

Our last 2024 discovery is one that I find extremely exciting. We talked about the vampire squid way way way back in episode 11, before some of my listeners were even born, and while it has the word squid in its name, it’s not exactly a squid. It’s also not exactly an octopus. It’s the last surviving member of its own order, Vampyromorphida, which shares similarities with both squids and octopuses. And as of 2024, the vampire squid is not the only member of its own order, because they’ve found a second vampire squid!

The vampire squid is a deep-sea animal that grows about a foot long, or 30 cm, and eats whatever organic material floats down from far above. That could mean part of a dead amphipod or it could mean fish poop, the vampire squid is not picky. The new species of vampire squid was found around 3,000 feet below the surface, or a little over 900 meters, in the South China Sea. A genetic study determined that it does seem to be a new species, and the scientific name Vampyroteuthis pseudoinfernalis has been proposed. The official description hasn’t yet been published, but that just means we’ll probably get to talk more about it in a future episode.

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 417: The Hoatzin

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I’m a bit under the weather this week, so here’s a Patreon episode about a weird bird!

Further reading:

Hoatzin nestling locomotion: acquisition of quadrupedal limb coordination in birds

Show transcript:

Welcome to the Patreon bonus episode of Strange Animals Podcast for mid-November, 2019!

We’re going to learn about a mystery bird today. When I say mystery bird, I don’t mean that people aren’t sure if it exists. It definitely exists. You can go to South America and look at it if you like, because fortunately it’s not rare or endangered. But scientists aren’t completely sure what it’s related to, because it’s a really weird bird.

The hoatzin [pronounced what-seen] is a large bird, over two feet long, or 65 cm. It’s shaped sort of like a pheasant, with a chunky body, long neck and small head, and a long tail made of stiff feathers like a hawk’s. Its face has no feathers and blue skin, it has red eyes, and it has a spiky feather crest on its head. It’s black and chestnut brown with some darker and lighter streaks, and is a softer brown underneath. It’s a really pretty bird, in fact, with a strong bill. But it really doesn’t resemble any other bird alive today.

The hoatzin is the only species in its genus, and the only genus in its family, and the only family in its order. It’s basically not really related to any other bird alive today, although in 2012 its genome was sequenced and found to be most closely related to cranes and plovers—but only very distantly. In fact, a 2015 study determined that the hoatzin started evolving separately from other birds 65 million years ago, right after the Cretaceous-Paleogene extinction event that killed off the non-avian dinosaurs.

We only have a few fossils of hoatzin ancestors, but they show that it was much more widespread in the past and lived in what is now North America and Europe. But these days it only survives in northern and central South America. It likes swampy areas and forests near rivers or other water.

The hoatzin eats plants—specifically leaves and buds, although it also eats some flowers and fruit. And leaves require a lot of digesting before the body can make use of the nutrients. The hoatzin’s digestive system is unlike any other living bird’s, because the hoatzin is a foregut fermenter. Its crop, which most birds only use to store extra food temporarily when the stomach is full, acts as a bacterial fermentation chamber—two chambers, in fact, since it’s divided into two sections. This acts like the rumen of a cow. Its crop is so big it doesn’t have room on its body for big flight muscles, so it’s not a strong flyer. It mostly stays in trees and bushes, eating leaves, flapping its big wings for balance and display, and hanging out with other hoatzins.

The hoatzin’s digestive system has a weird side effect. It smells bad. It’s supposed to smell like manure. It’s sometimes called the stinkbird and, fortunately for the hoatzin, almost no one wants to eat it as a result.

As you probably know, birds developed from dinosaurs. It’s easy to forget that, since birds have evolved structures like toothless beaks and front legs modified for flight and they no longer have lizard-like tails. But the hoatzin retains something from its dinosaur ancestry that is a startling reminder.

The hoatzin is a social bird that lives in small flocks. It breeds during the local rainy season and builds its nest over water when the forest floods due to rain. The female lays two or three eggs, and when the babies hatch, they can climb around in the branches near the nest right away. This means they can hide from predators instead of being helpless in the nest. And the reason a hoatzin chick can climb so well is partly because it has big feet, and partly because it has finger claws on its wings: specifically a thumb claw and one finger claw, which are fully functional and make it look a lot like a fuzzy baby dinosaur.

Not only does the baby hoatzin use these claws for climbing, a study published in May 2019 shows that the baby hoatzin uses its wings differently when climbing than it does as an adult bird. Obviously, birds fly by flapping both wings at the same time. But the baby hoatzin climbs by using its limbs in an alternating motion. You know, the way you would climb a tree. Or the way a small dinosaur would climb a tree.

But primitive and dinosaur-like as this trait is, researchers have discovered that it developed relatively recently. That is, as the hoatzin’s distant ancestors evolved from a small dinosaur into a primitive bird, it lost the claws on its front legs as they became more and more modified into wings. But at some point, the hoatzin re-developed those claws. Researchers think it’s what is called an atavistic trait, which you may remember from way back in the Patreon episode where we talked about horses with extra toes. In other words, the genes to grow claws on the front limbs are still present in birds, but are suppressed by other genes, since claws just get in the way when you’re flying. But occasionally a small mutation causes the claws to grow anyway, and in the case of the hoatzin, it proved so useful that those babies with claws survived better than those without claws, and therefore lived to pass on their genes. But the claws are no longer useful once the babies grow up and learn how to fly, so they lose them as adults.

Hoatzin chicks climb using alternating motions of the wings, but swim by moving both wings together. Oh, didn’t I mention that the babies swim? They have to, because sometimes a predator attacks and they have to get away fast. They can’t fly yet, and they can’t climb all that quickly, so they drop out of the branches and fall into the water below. That’s why the parent birds build the nests over water. The babies can swim just fine, and they swim to safety and climb back up into the branches where their parents can find them.

The hoatzin isn’t the only bird that has wing claws as a baby. Some species of turaco do too. The turaco lives in Africa and shares many traits with the hoatzin, so for a long time people thought the two were related. But now we know they’re not and that the similarities are due to convergent evolution.

Thanks for your support, and thanks for listening!

Episode 416: The heaviest tarantula and the bitey-est ant

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Thanks to Siya, Sutton, Owen, and Aksel for suggesting this week’s topic, the Goliath birdeater tarantula and the fire ant!

Further listening:

The TEETH Podcast

Further reading:

Tropical fire ants traveled the world on 16th century ships

The Goliath birdeater tarantula, bigger than some kittens:

Fire ants:

Show transcript:

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

This week we’re going to talk about two invertebrates, a spider and an insect. Thanks to Siya, Sutton, Owen, and Aksel for suggesting them!

We’ll start with the spider, which Siya and Sutton both suggested. It’s the goliath tarantula, also called the goliath birdeater. You know it has to be a big spider if it’s called a birdeater. We’ve talked about it before, but not in a long time.

The goliath birdeater is the heaviest spider in the world. If you think of the usual spider, even a big one, it’s still pretty lightweight. Let’s use a wolf spider as an example, which is found just about everywhere in the world. It’s a hunting spider that doesn’t spin a web, and while different species vary in size, the biggest is the Carolina wolf spider found in many parts of North America. A big female can have a legspan of four inches across, or 10 cm, with a body up to an inch and a half long, or 35 mm—but it weighs less than an ounce. That’s barely 28 grams, or just a little heavier than five sheets of printer paper.

In comparison, the goliath birdeater tarantula can weigh over 6 ounces, or 175 grams. That’s heavier than a baseball, or two packs of cards. Its legspan can be as much as 12 inches across, or 30 cm with a body length of about 5 inches, or 13 cm. It’s brown or golden in color and lives in South America, especially in swampy parts of the Amazon rainforest. It’s nocturnal and mostly eats worms, large insects, other spiders, amphibians like frogs and toads, and occasionally other small animals like lizards or even snakes. And yes, every so often it will catch and eat a bird, but that’s rare. Birds are a lot harder to catch than worms, especially since the Goliath birdeater lives on the ground, not in trees.

Because it’s so large, the goliath looks like it would be incredibly dangerous to humans. It does have fangs and can inflict a venomous bite, but it’s not very strong venom. The danger comes from a very different source, because the goliath birdeater is famous for its urticating spines.

Many species of tarantula have special setae, hairlike structures called urticating spines, that can be dislodged from the body easily. If a tarantula feels threatened, it will rub a leg against its abdomen, dislodging the urticating spines. The spines are fine and light so they float upward away from the spider on the tiny air currents made by the tarantula’s legs, and right into the face of whatever animal is threatening it. The spines are covered with microscopic barbs that latch onto whatever they touch. If that’s your face or hands, they are going to make your skin itch painfully, and if it happens to be your eyeball you might end up having to go to the eye doctor for an injured cornea. Scientists who study tarantulas usually wear eye protection.

The goliath birdeater tarantula is considered a delicacy in northeastern South America. People eat it roasted. Apparently it tastes kind of like shrimp.

Next, Owen and Aksel wanted to learn about fire ants. I couldn’t believe that we’ve never talked about fire ants before!

Fire ant is the name for any of the more than 200 species in the genus Solenopsis, but it’s typically used to refer to the species Solenopsis invicta. It’s native to tropical South America but has been introduced to parts of North America, Australia, China, Taiwan, India, Africa, and many other places where the climate is tropical or sub-tropical.

The fire ant initially became so invasive due to Spanish galleons in the 16th century, which carried trade goods around the world. A ship that’s meant to carry a lot of cargo is built so that it needs to be weighted down to a certain degree to sail safely. A lot of times if a Spanish ship didn’t have enough goods in its hold to make it weigh enough, the captain would bring a few tons of soil onboard to make up the difference. Then, when the ship got to its next port where it was supposed to pick up new cargo, it would just dump the dirt wherever it was. It didn’t matter to the fire ant if the dirt was dumped into the water, because fire ants are prepared for their nests getting flooding. They cling together and form huge rafts that the wind pushes to shore. But more often, the dirt would get dumped on land for other ships to re-use.

A team of scientists figured out where the invasive fire ant populations came from by comparing the genetic signatures of 192 different populations. They hypothesized that the ants with the highest genetic diversity were the original population, and that as the ants were moved around the world by ship, genetic diversity would get lower and lower, since all the ants were descendants of the original colony or colonies transported accidentally in the dirt. They mapped out the genetics, then compared the results to Spanish trade routes in the mid-1600s, and it all matched up.

The fire ant made it to the United States in the late 1930s or early 1940s, the West Indies around 1980, and Australia around 2001. These days a lot of fire ants end up transported to new areas in golf course sod imported from Florida.

A fire ant colony consists of a queen, thousands of worker ants, and larger soldier ants that protect the workers and especially the queen. Some colonies have more than one queen. The ants eat anything, including seeds and insects, and even small animals, but also including dead animals they find. The colony can have as many as a quarter million ants. The nest is underground and entrances can be far from the nest itself, and nests can be so large that they can cause structures built over them to collapse.

Invasive animals of any kind aren’t good for the native animals, and the same is true for the fire ant. The fire ant specializes in colonizing areas where humans have disturbed the ground, whereas native ants often have trouble surviving in disturbed areas. The fire ants crowd out native ants and can destroy some native plants.

But the main reason why people don’t like fire ants is that they bite and they’re venomous. The bites cause a burning sensation and painful swelling, but some people are allergic to the venom and can actually die from ant bites. Luckily, that’s rare, but the bites are still painful.

Some countries have spent millions of dollars trying to eradicate the fire ant, including Australia and New Zealand. New Zealand seems to have succeeded, but Australia is still struggling to get the invasion under control. Fortunately, a lot of animals eat fire ants, which helps. One of the animals that especially loves to eat fire ants is the wolf spider, so now we’ve come full circle in this episode.

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!

If you are wishing that I’d gone into more detail about fire ant attacks, you might like the TEETH podcast. It’s the only podcast where you’ll hear wild animal attack stories directly from the survivors, hosted by a wilderness guide and attack survivor himself. I’ll put a link in the show notes so you can go listen. It’s appropriate for all ages. I don’t think they’ve actually covered a fire ant attack, but they’ve got lots of other fascinating accounts.