Category Archives: invertebrates

Episode 455: Spooky Animals

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Thanks to Richard of NC, Richard my brother, Siya, Ezra, and Owen and Aksel for their suggestions this week!

Further reading:

Creature Feature: Googly-Eyed Stubby Squid

Nocturnal Spiders Use Trapped Fireflies as Glowing Bait to Attract Additional Prey

A male vampire deer:

The adorable googly eyed squid [still taken from video linked above]:

The snowy owl [photo by Bill Bouton from San Luis Obispo, CA, USA – Snowy Owl, Bubo scandiacus, male, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=19899431]:

Show transcript:

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

This week for monster month, let’s learn about some animals that are considered spooky, although in actuality they’re just regular animals who don’t even know the meaning of spooky. Thanks to Ezra, Owen and Aksel, Richard from NC, my brother Richard, and Siya for their suggestions!

We’ll start with the two Richards. Richard from NC suggested vampire deer, and my brother Richard suggested zombie salmon.

The vampire deer is more commonly called the water deer, but considering it has tusks growing down from its upper jaw that look like fangs, vampire deer is an excellent name. Females have short tusks, but in males they grow quite long, sometimes over 3 inches long, or 8 cm. Since the animal only stands about two feet tall at the shoulder, or 65 cm, that’s pretty impressive. Its hind legs are longer than its front, so that when it runs it sort of bounces like a rabbit. It has a very short tail, small rounded ears, and is golden brown in color with a lighter underside. It doesn’t have antlers. We talked about the musk deer in episode 366, which also has fangs instead of antlers, but the vampire deer isn’t closely related to the musk deer.

The vampire deer currently lives in Korea, China, and Russia although it used to be much more widespread. It mostly lives in reedy habitats near rivers, and it’s a solitary animal although females will sometimes congregate to eat. Males protect their territories by fighting with their tusks, although they don’t actually drink blood.

As for the zombie salmon, it’s not a type of fish but something that can happen to an ordinary salmon. The salmon is a fish that famously spends most of its adult life in the ocean, but travels up rivers to spawn. The eggs hatch in freshwater and the baby fish grow up in the river, and then they migrate to the ocean and live there for almost the rest of their lives. Eventually the fish is fully mature and ready to spawn, so it travels to the river where it was hatched, fights its way upstream, and the cycle starts all over with the new generation.

Almost all salmon die after spawning. This is partly because the energy requirements of swimming upstream is so high, but also because a salmon is genetically programmed to die after spawning. This is called senescence, and while it’s common in invertebrates like octopuses and some insects, it’s rare in vertebrates. Not only that, there’s not enough food for an adult salmon in the spawning area, and an adult salmon’s body is adapted for salt water, not fresh water, so it can’t live long in rivers as an adult anyway.

A small number of female Atlantic salmon are able to return to the ocean, recover and regain their strength, and spawn again a few years later, but for all other species, after spawning, that’s it. Within days all the salmon have died.

But sometimes, rarely, a salmon remains alive for weeks after spawning. It doesn’t have the energy to return to the ocean, and its body is in the process of shutting down for planned senescence, and the freshwater is causing damage to the fish’s skin. But still it survives, growing more and more raggedy, just like a zombie in a movie. But unlike movie zombies, it doesn’t want to eat brains. Eventually the zombie salmon dies, if something doesn’t catch and eat it first.

Next, Siya suggested the googly-eyed squid. Some people find squid and octopuses scary because they look so strange, but I admit I added this squid to the episode because I think its name is funny. It’s also called the stubby squid or the googly-eyed stubby squid. Its scientific name is Rossia pacifica, which gives you a hint that it lives in the northern Pacific Ocean. In the winter it likes shallow water without strong currents, but in summer it migrates to deeper water where it doesn’t get too warm.

The googly-eyed squid is small and closely related to the cuttlefish. It grows less than four and a half inches long, or 11 cm, including its eight short arms and two retractable tentacles. It’s usually reddish-brown or purplish in color, but like most squid it can change color when it needs to. It gets its name because it has large eyes that show white around the edges and have a black pupil, which makes it look like it has googly eyes.

During the day, the googly-eyed squid buries itself most of the way in sand or mud at the bottom of the sea floor, with just its googly eyes showing so it can watch for danger. At night it comes out to hunt small animals like crabs and other crustaceans, mollusks, and fish, but what it really likes is shrimp. Naturally, it has good eyesight.

Next, let’s talk about a bird that some people find spooky. Ezra, Owen, and Aksel all suggested the snowy owl.

The snowy owl is mostly snow-white although young birds have black and gray markings. Its eyes are yellow and it often hunts in the daytime, but not always. Its wingspan can be as much as six feet across, or 1.8 meters.

The snowy owl lives throughout the Arctic and nearby regions, especially in summer, but sometimes travels long distances to find food. It’s also migratory, traveling south for the winter. Snowy owls have been spotted in such far-flung places as Hawaii, Bermuda, Pakistan and India, Iran, and Japan and Korea.

The snowy owl mostly eats small animals like lemmings and mice, although it will kill and eat pretty much anything it can catch, including ducks and other water birds, fish, and even insects and frogs. It will sometimes eat carrion and even sometimes steals food from other birds. It swallows small animals whole, and a day or two later, regurgitates a compacted pellet made up of the indigestible parts, including bones and fur. A lot of predatory birds do this, not just snowy owls. Scientists who study the birds love finding these pellets, because they can dissect them and learn what the bird has been eating.

Not only does the snowy owl make its nest on the ground, sometimes it hunts on the ground too, just running along after an animal on its big feet.

This is what the snowy owl sounds like:

[owl call]

Let’s finish with an invertebrate that a lot of people are scared of, a spider! This particular spider is a species of sheet-web spider, which lives in Taiwan. It’s a nocturnal spider that was only described in 2012. Unlike a lot of spiders, which build upright webs to trap insects that are flying along between branches and twigs, the sheet-web spider builds its web horizontally just above the ground.

The webs are light-colored and reflect light. The spiders build their webs in shady areas, and scientists think that moths see the light reflecting off the webs, and think the webs are actually the ground in an area open to the sky. Moths like open areas like this, and moths also happen to be one of the spider’s favorite foods. When a group of scientists experimented by darkening some webs with charcoal dust, they determined that the darkened webs attracted considerably fewer moths.

But it turns out that the sheet-web spider does something even more extraordinary. If a firefly gets caught in the web, the spider doesn’t eat it—or at least, not right away. It lets it stay in the web, flashing its light. Scientists noticed this and were intrigued. Did the fireflies not taste good, or was something else going on?

They placed LEDs that blinked like fireflies in some webs, but not in others, and monitored the results. It turns out that three times the number of insects were attracted to the webs with fake fireflies, and most of those were other fireflies. Fireflies attract a mate by flashing. The spiders were taking advantage of having a built-in lure stuck in their webs. So even though spiders are very tiny and have tiny brains, sometimes they’re pretty darn smart.

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 447: So Many Legs!

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Thanks to Mila for suggesting one of our topics today!

Further reading:

The mystery of the ‘missing’ giant millipede

Never-before-seen head of prehistoric, car-size ‘millipede’ solves evolutionary mystery

A centipede compared to a millipede:

Show transcript:

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

Let’s finish invertebrate August this year with two arthropods. One is a suggestion from Mila and the other is a scientific mystery that was solved by a recent discovery, at least partially.

Mila suggested we learn about centipedes, and the last time we talked about those animals was in episode 100. That’s because centipedes are supposed to have 100 legs.

But do centipedes actually have 100 legs? They don’t. Different species of centipede have different numbers of legs, from only 30 to something like 300. Like other arthropods, the centipede has to molt its exoskeleton to grow larger. When it does, some species grow more segments and legs. Others hatch with all the segments and legs they’ll ever have.

A centipede’s body is flattened and made up of segments, a different number of segments depending on the centipede’s species, but at least 15. Each segment has a pair of legs except for the last two, which have no legs. The first segment’s legs project forward and end in sharp claws with venom glands. These legs are called forcipules, and they actually look like pincers. No other animal has forcipules, only centipedes. The centipede uses its forcipules to capture and hold prey, and to defend itself from potential predators. A centipede pinch can be painful but not dangerous unless you’re also allergic to bees, in which case you might have an allergic reaction to a big centipede’s venom. Small centipedes can’t pinch hard enough to break a human’s skin.

A centipede’s last pair of legs points backwards and sometimes look like tail stingers, but they’re just modified legs that act as sensory antennae. Each pair of a centipede’s legs is a little longer than the pair in front of it, which helps keep the legs from bumping into each other when the centipede walks.

The centipede lives throughout the world, even in the Arctic and in deserts, but it needs a moist environment so it won’t dry out. It likes rotten wood, leaf litter, soil, especially soil under stones, and basements. Some centipedes have no eyes at all, many have eyes that can only sense light and dark, and some have relatively sophisticated compound eyes. Most centipedes are nocturnal.

The largest centipedes alive today belong to the genus Scolopendra. This genus includes the Amazonian giant centipede, which can grow over a foot long, or 30 cm. It’s reddish or black with yellow bands on the legs, and lives in parts of South America and the Caribbean. It eats insects, spiders–including tarantulas, frogs and other amphibians, small snakes and lizards, birds, and small mammals like mice. It’s even been known to catch bats in midair by hanging down from cave ceilings and grabbing the bat as it flies by.

Some people think that the Amazonian giant centipede is the longest in the world, but this isn’t actually the case. Its close relation, the Galapagos centipede, can grow 17 inches long, or 43 cm, and is black with red legs.

But if you think that’s big, wait until you hear about the other animal we’re discussing today. It’s called Arthropleura and it lived in what is now Europe and North America between about 344 and 292 million years ago.

Before we talk about it, though, we need to learn a little about the millipede. Millipedes are related to centipedes and share a lot of physical characteristics, like a segmented body and a lot of legs. The word millipede means one thousand feet, but millipedes can have anywhere from 36 to 1,306 legs. That is a lot of legs. It’s probably too many legs. The millipede with 1,306 legs is Eumillipes persephone, found in western Australia and only described in 2021. It lives deep underground in forested areas, where it probably eats fungus that grows on tree roots. It’s long and thin with short legs and no eyes. It’s only about 1 mm in diameter, but can grow nearly 4 inches long, or almost 10 cm.

Millipedes mostly eat decaying plant material and are generally chunkier-looking than centipedes. They have two pairs of legs per segment instead of just one, with the legs attached on the underside of the segment instead of on the sides. A millipede usually has short, strong antennae that it uses to poke around in soil and decaying leaves. It can’t pinch, sting, or bite, although some species can secrete a toxic liquid that also smells terrible. Mostly if it feels threatened, a millipede will curl up and hope the potential predator will leave it alone.

The biggest millipede alive today is probably the giant African millipede, which can grow over 13 inches long, or almost 34 cm, but because millipedes are common throughout the world and are often hard for scientists to find, there may very well be much larger millipedes out there that we just don’t know about.

As an example, in 1897 scientists discovered a new species of giant millipede in Madagascar and named it Spirostreptus sculptus. One specimen found was almost 11 inches long, or over 27 cm. But after that, no scientist saw the millipede again—until 2023, when a scientific expedition looking for lost species rediscovered it, along with 20 other species of animal. It turns out that the millipede isn’t even uncommon in the area, so the local people probably knew all about it.

But Arthropleura was way bigger than any millipede or centipede alive today. It could grow at least 8 ½ feet long, or 2.6 meters, and possibly longer. It probably weighed over 100 lbs, or 45 kg. We have plenty of fossilized specimens, but not one of them has an intact head. Then scientists discovered two beautifully preserved juvenile specimens in France, and CT scans in 2024 revealed that both specimens had nearly complete heads.

The big question about Arthropleura was whether it was more closely related to millipedes or centipedes, or if it was something very different. Without a head to study, no one could answer that question with any confidence, although a lot of scientists had definite opinions one way or another. Studies of the head scans determined that Arthropleura was indeed more closely related to modern millipedes—but naturally, since it lived so long ago, it also had a lot of traits more common in centipedes today. It also had something not found in either animal, eyes on little stalks.

There are still lots of mysteries surrounding Arthropleura. For instance, what did it eat? Because of its size, scientists initially thought it might be a predator. Now that we know it was more closely related to the millipede than the centipede, scientists think it might have eaten like a millipede too. That would mean it mostly ate decaying vegetation, but we don’t know for sure. We also don’t know if it could swim or not. We have a lot of Arthropleura tracks that seem to be made along the water’s edge, so some scientists hypothesize that it could swim or at least spent part of its time in the water. Other scientists point out that Arthropleura didn’t have gills or any other way to absorb oxygen while in the water, so it was more likely to be fully terrestrial. The first set of scientists sometimes comes back and argues that we don’t actually know how Arthropleura breathed or even why it was able to grow so large, and maybe it really did have gills. A third group of scientists then has to come in and say, hey, everyone calm down, maybe the next specimen we find will show evidence of both lungs and gills, and it spent part of its time on land and part in shallow water, so there’s no need to argue. And then they all go for pizza and remember that they really love arthropods, and isn’t Arthropleura the coolest arthropod of all?

At least, I think that’s how it works among scientists. And Arthropleura is really cool.

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 446: Termites

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Thanks to Yonatan and Eilee for this week’s suggestion!

Further reading:

Replanted rainforests may benefit from termite transplants

A vast 4,000-year-old spatial pattern of termite mounds

A family of termites has been traversing the world’s oceans for millions of years

Worker termites [photo from this site]:

Show transcript:

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

This week we have a topic I’ve been wanting to cover for a while, suggested by both Yonatan and Eilee. It’s the termite episode!

We talk a lot about animals that eat termites, and in many cases termite-eating animals also eat ants. I’ve always assumed that termites and ants are closely related, but they’re not. Termites are actually closely related to cockroaches, which are both in the order Blattodea, but it’s been 150 million years since they shared a common ancestor. They share another trait too, in that no one wants either insect infesting their house.

Like most cockroach species, though, most termite species don’t want anything to do with humans. They live in the wild, not in your house, and they’re incredibly common throughout most of the world. That’s why so many animals eat termites almost exclusively. There are just so many termites to eat!

There are around 3,000 species of termite and about a third of them live in Africa, with another 400 or so in South America, 400 or so in Asia, and 400 or so in Australia. The rest live in other parts of the world, but they need warm weather to survive so they’re not very common in cold areas like northern Europe.

A termite colony consists of a queen, soldiers, and workers, which sounds very similar to ants, but there are some major differences. Worker termites take care of the nest and babies, find and process food so the other termites can eat it, and store the processed food. They also take care of the queen. Unlike ants and bees, worker termites aren’t only female and aren’t always sterile. Soldiers are bigger and stronger than workers, with much bigger heads and jaws so they can fight off potential predators. In some species, the soldiers have such big jaws that they can’t actually eat without help. Worker termites feed them. Finally, the queen is the largest individual in the colony, usually considerably larger than workers, but unlike queen bees and ants, she has a mate who stays with her throughout her life, called a king. Some termite queens can live to be as much as 50 years old, and she and the king spend almost their entire lives underground in a nesting chamber.

The larger the colony, the more likely it is that the colony has more than one queen. The main queen is usually the one that started the colony along with her king, and when it was new they did all the work—taking care of the eggs and babies, foraging for food, and building the nest itself. As the first workers grew up, they took on more of those tasks, including expanding the nest.

Workers are small and their bodies have little to no pigment, so that they appear white. Some people call them white ants, but of course they’re not ants. Workers have to stay in a humid environment like the nest or their bodies dry out. Workers and soldiers don’t have eyes, although they can probably sense light and dark, and instead they navigate using their antennae, which can sense humidity and vibrations, and chemoreceptors that sense pheromones released by other termites.

Termites have another caste that’s not as common, usually referred to as reproductives. These are future kings and queens, and they’re larger and stronger than workers. They also have eyes and wings. When outside conditions are right, usually when the weather is warm and humid, the reproductive termites leave the nest and fly away. Males and females pair off and search for a new nesting site to start their own colony.

Termites mainly eat dead plant material, including plant material that most other animals can’t digest. A termite’s gut contains microbes that are found nowhere else in the world, which allow the termite to digest cellulose found in plants, especially wood. Baby termites aren’t born with these microbes, but they gain them from worker termites when the babies are fed or groomed.

In some areas termites will eat the wood used to build houses, which is why people don’t like them, but termites are actually important to the ecosystems where they live, recycling nutrients and helping break down fallen trees so other plants can grow. They also host nitrogen-fixing bacteria, which are important to plant life.

A recent study in Australia determined that termites are really important for rainforest health. In some parts of Australia, conservation groups have started planting rainforest trees to restore deforested areas. Decomposers like termites are slower to populate these areas, with one site that was studied 12 years after planting showing limited termite activity. That means it takes longer for fallen branches, logs, and stumps to decay, which means it takes longer for the nutrients in those items and others to be available for other plants to use.

The problem seems to be that the new forests don’t have very many dead trees yet, so the termites don’t have a lot to eat. The team is considering bringing in fallen logs from more established forests so the termites have food and can establish colonies more easily.

Some species of termite in Africa, Australia, and South America build mounds, and those mounds can be huge. A mound is built above ground out of soil and termite dung, held together with termite saliva. It’s full of tunnels and shafts that allow the termites to move around inside and which bring air into the main part of the nest, which is mostly below ground. Different species build differently-shaped mounds, including some that are completely round.

Some termite mounds can be twice the height of a tall person, and extremely big around. The biggest measured had a diameter of almost 100 feet around, or 30 meters. But in at least one place on earth, in northeastern Brazil, there’s a network of interconnected termite mounds that is as big as Great Britain.

The complex consists of about 200 million mounds, each of them about 8 feet tall, or 2.5 meters, and about 30 feet across, or 9 meters. They’re just huge piles of soil excavated from underground, and tests have determined that the mounds range in age from 690 years old to at least 3,820 years old and are connected by tunnels–but the nests under the mounds are still in use!

Not all termite species build mounds or even live underground. A group called drywood termites live in wood and usually have much smaller colonies than other termites. They probably split off from other termites about 100 million years ago, and a 2022 genetic study determined that they probably originated in South America. But drywood termites have spread to many other parts of the world, and scientists think it’s because their homes float. They estimate that over the last 50 million years, drywood termites have actually floated across entire oceans at least 40 times. When their floating log homes washed ashore, the termites colonized the new land and adapted to local conditions.

A lot of people worry that termites will damage their homes, but in many parts of the world, people eat termites. The termites are fried or roasted until they’re nicely crunchy, and they’re supposed to have a nut-like flavor. They’re also high in protein and important fats. So the next time you worry about your house, you can shout at any potential termites that if they’re around, you might just eat them as a snack.

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 445: Salinella

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It’s a tiny mystery animal!

Further reading:

Salinella – what the crap was it?

Some of Frenzel’s drawings of Salinella:

Show transcript:

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

Johannes Frenzel was a German zoologist in the 19th century. He worked in Argentina for several years, studying microscopic and near-microscopic animals, and seemed to be a perfectly good scientist who did good work but didn’t make a real splash. But these days he’s remembered for a mystery animal that is still causing controversy in the scientific community.

Frenzel described a strange worm-like animal he named Salinella salve in 1892, and Salinella hasn’t been seen since. According to Frenzel’s description of it, Salinella is very different from every other animal known. It’s so different, in fact, that some scientists think Frenzel just made the whole thing up.

In 1890 or 1891, a colleague gave Frenzel a soil sample reportedly from the salt pans in Argentina. We don’t know exactly where it came from, just that it’s somewhere in the Río Cuarto region. Frenzel put the sample in an aquarium and added water, although apparently some iodine got mixed in too, either on purpose or maybe by accident. Then he forgot all about the sample for a few weeks. It wasn’t covered and Frenzel reported that some dead flies had fallen into the aquarium.

When Frenzel finally got around to examining the sample, he discovered something he had never seen before. No one else had either, before or since. He said it was a worm-like animal about 2 millimeters long, and there wasn’t just one of them. There were quite a few in the sample, some in the soil and some attached to the glass.

When he studied the tiny worms, he discovered they had a very basic, very unusual body plan. It was basically just a tube open at both ends, with a single layer of cells around the interior sac. Each cell was covered with cilia on both the exterior side of the animal and the interior side. Cilia are hair-like structures, and salinella used them to move around, a method of propulsion called ciliary gliding. It didn’t have any organs or even tissues—basically nothing you’d expect even in a very simple animal. It reproduced by splitting down the middle, called transverse fission.

Assuming Frenzel was describing a real animal, and was describing it accurately, this body plan is unlike any other animal known. It’s most similar to what scientists think the body plan was of the precursors to sea sponges. It’s also similar in some ways to a group of parasitic animals called Mesozoa, which are wormlike, very simple, only a few millimeters long at most, and which have an outer layer of ciliated cells. Mesozoans aren’t well understood and most scientists these days think the group is made up of animals that aren’t closely related to each other. Salinella has sometimes been considered a mesozoan, but it’s still not that close of a match.

Frenzel took detailed notes and made careful drawings of Salinella, and compared it to known animals like protozoans. His description of the animal is solid, and he described many other animals in his career that are well-known to scientists today. The main reason some scientists now think Frenzel made Salinella up is because it’s so weird and no one has been able to find it since. Frenzel died in 1897 without ever having the chance to look for more specimens.

In 1963 an American biologist placed Salinella in its own phylum, which he named Monoblastozoa. In the early 2010s, a team of German scientists visited various saline lakes in Argentina and Chile in hopes of finding Salinella specimens, but without luck. The area where the original soil sample came from has mostly been converted to farmland, so if Salinella was restricted to that one spot, it might well be extinct now.

So what happened to the type specimens that Frenzel collected? We don’t know. They vanished sometime between 1891 when Frenzel moved back to Germany from Argentina, and now. It might even be that he couldn’t preserve the specimens, since he reported that every time he tried to preserve one, it disintegrated.

While I was researching this episode, I wondered if Salinella actually came from the flies that reportedly fell into the aquarium. Many parasites evolve to become very simple, like Myxozoa that we talked about in episode 422. But Frenzel observed Salinella apparently eating organic matter in the soil, which isn’t something a fly parasite would or could do.

At this point, unless we can find a living Salinella specimen, there’s no way to know if the animal was real or a figment of Frenzel’s imagination. Some scientists even suggest that Frenzel was mistaken in his description and the real animal might actually be very different from what he described. Considering how detailed and careful Frenzel’s notes and drawings are, and how many other species he described without causing any controversy at all, I think Salinella was a real animal, just a weird one. Let’s hope that one day it’s discovered again so we can learn more about it.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. 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 444: Diskagma and Horodyskia

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It’s Invertebrate August! These creatures are the most invertebrate-y of all!

Further reading:

Dubious Diskagma

Horodyskia is among the oldest multicellular macroorganisms, finds study

A painting of diskagma, taken from the top link above:

Little brown jug flowers (not related to diskagma in any way!):

Show transcript:

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

This episode started out as the March 2025 Patreon episode, but there was more I wanted to add to it that I didn’t have time to cover in that one. Here’s the expanded version to kick off Invertebrate August, which also happens to be episode 444 and releasing on August 4th! It’s about two mystery fossils.

The first is named Diskagma, which means disc-shaped fragment, and it was only described in 2013. That’s partly because it’s so small, barely two millimeters long at most, and partly because of where it’s found. That would be fossilized in extremely old rocks.

When I saw the illustration accompanying the blog post where I learned about Diskagma, I thought it was a cluster of cup-like flowers, sort of like the flowers of the plant called little brown jug. I was ready to send the link to Meredith Hemphill of the Herbarium of the Bizarre podcast, which by the way you should be listening to. But then I saw how old Diskagma is.

It’s been dated to 2.2 billion years old. That’s older than any plant, probably by as much as a billion years.

Even more astounding, it lived on land.

As a reminder, the Cambrian explosion took place about half a billion years ago, when tiny marine animals diversified rapidly to fill new ecological niches. That happened in the water, though, mainly in shallow, warm oceans. If you go back to around 850 million years ago, that may have been roughly the time that land plants evolved from green algae that lived in fresh water. Plant-like algae, or possibly algae-like plants, might be as old as 1 billion years old. But before then, scientists don’t find evidence of anything except microbes living on land, and they were probably restricted to lakes and other bodies of fresh water. That’s because there wasn’t much soil, just broken-up rock that contained very few nutrients and couldn’t retain much water.

Diskagma was shaped like a tiny elongated cup, or an urn or vase, with what looks like a stem on one end and what looks like an opening at the other end. The opening contained structures that look like little filaments, but the filaments didn’t fill the whole cup. Most of the cup was diskagma’s body, so to speak, although we don’t know what it contained. We also don’t know what the filaments were for. We do know that the stem actually did connect diskagma to other cups, so that they lived in little groups. We don’t know if it was a single animal with multiple cuplike structures or if it was a colony, or really anything.

That’s the problem. We don’t know anything about diskagma except that it existed, and that it lived on land 2.2 billion years ago. Tiny as it was, though, it wasn’t microscopic, and it definitely appears more complex than would be expected that long ago, especially from something living on dry land.

One suggestion is that the main part of its body contained a symbiotic bacteria that could convert chemicals to nutrients. As in many modern animals, especially extremophiles, the bacteria would have had a safe place to live and the diskagma would have had nutrients that allowed it to live without needing to eat.

Diskagma lived at an interesting time in the earth’s history, called the great oxygenation event, also called the great oxidation event. We talked about it in episode 341 in conjunction with cyanobacteria, because cyanobacteria basically started the great oxygenation event. Cyanobacteria are still around, by the way, and are doing just fine. They’re usually called blue-green algae even though they’re not actually algae.

Cyanobacteria photosynthesize, and they’ve been doing so for far longer than plants–possibly as much as 2.7 billion years, although scientists think cyanobacteria originally evolved around 3.5 billion years ago. The earth is about 4.5 billion years old, if you were wondering.

Like most plants also do, cyanobacteria produce oxygen as part of the photosynthetic process, and when they started doing so around 2.7 billion years ago, they changed the entire world. Before then, earth’s atmosphere hardly contained any oxygen. If you had a time machine and went back to more than two billion years ago, and you forgot to bring an oxygen tank, you’d instantly suffocate trying to breathe the air. But back then, even though animals and plants didn’t yet exist, the world contained a whole lot of microbial life, and none of it wanted anything to do with oxygen. Oxygen was toxic to the lifeforms that lived then, but cyanobacteria just kept producing it.

Cyanobacteria are tiny, but there were a lot of them. Over the course of about 700 million years, the oxygen added up until other lifeforms started to go extinct, poisoned by all that oxygen in the oceans and air. By two billion years ago, pretty much every lifeform that couldn’t evolve to use or at least tolerate oxygen had gone extinct.

Since Diskagma lived during the time of the great oxygenation event, some scientists suggest that it contained microbes that photosynthesized sunlight into nutrients diskagma could use. And, as in cyanobacteria, the side effect of photosynthesis is oxygen, so diskagma might have been contributing to the oxygen in the air that allows us to breathe these days. On the other hand, it might not have had anything to do with photosynthesis and the great oxygenation event might have driven diskagma to extinction. We have no way to know right now.

What we do know is that 700 million years after diskagma lived, something similar appears in the fossil record. It’s called Horodyskia and its fossils have been found in rocks dating between 1.5 billion years ago to 550 million years ago. Unlike diskagma, which has only been found in rocks from South Africa, horodyskia fossils have been found in Australia, China, and North America. That doesn’t mean diskagma wasn’t widespread, just that we haven’t found it anywhere else. There aren’t all that many rocks that are over two billion years old.

Horodyskia lived in the water, specifically at the bottom of the ocean, probably in shallow water. It’s been described as looking like a row of beads on a thread. The thread seemed to be buried in the sand, and growing up from it in intervals were little pear-shaped bulbs, each no larger than a millimeter long, that stuck up through the sand into the water. There may have been little root-like structures called holdfasts that grew from the bottom of the thread to help keep it in place.

We don’t know a lot about horodyskia either. It wasn’t a plant, since it also lived long before plants evolved. A 2023 study determined that it was a multicellular creature and that it was most likely a protist. Protists are related to animals, plants, and fungi, but aren’t any of those things, and they’re an incredibly diverse group. Most are single-celled and microscopic, but not always. They include algae, amoebas, slime molds, and lots more. Horodyskia’s bulbs might have been encased in a jelly-like substance, as is common in a lot of protists. Some horodyskia specimens found in younger rocks, the ones about 550 million years old, are much smaller than the earlier specimens, with each bulb barely a fraction of a millimeter in size.

We might not know much about these strange life forms, but knowing they existed tells us that even two billion years ago, life was a lot more varied than we used to think. And that’s the most exciting thing of all.

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 443: Ant Lions and the Horrible Seal Problem

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Thanks to Jayson and warblrwatchr for suggesting this week’s invertebrates!

Further reading:

Parasite of the Day: Orthohalarachne attenuata

Trap-jaw ants jump with their jaws to escape the antlion’s den

Get out of my noooooose:

An ant lion pit:

An ant lion larva:

A lovely adult antlion, Nannoleon, which lives in parts of Africa [photo by Alandmanson – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=58068259]:

Show transcript:

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

It’s almost August, and of course we’re doing invertebrate August again this year. Let’s get ready by talking about a few extra invertebrates this week, with suggestions from Jayson and warblrwatchr.

Before we get started, I have some quick housekeeping. First, a big shout-out to Nora who emailed me recently. I just wanted to say hi and I hope you’re having a good day. Next, I’m moving in just a few weeks to Atlanta, Georgia! I know I was talking forever about moving to Bloomington, Indiana, but I changed my mind. The next few episodes are already scheduled so I can concentrate on moving.

I’m about 75% packed at this point and have given away or sold a lot of stuff, including a lot of books. But I have a collection that a listener might be interested in. I offered it to the patrons last month but no one grabbed it, so I’ll offer it here.

I have every issue of the little magazine Flying Snake ever published, 30 in all. They’re a fun hodgepodge of articles, reprinted newspaper clippings, old photos, and other stuff more or less associated with cryptozoology and weirdness in general. I’ve decided they take up too much space on my shelves to take with me to Atlanta. If you’re interested in giving them a home, let me know and I’ll box them up and send them to you for free. The first person who says they’ll take them will get them, but the catch is that you have to take them all. I won’t just send you a few. I’ll also throw in all four volumes of the Journal of Cryptozoology. This offer stands until mid-August when I move, because if I have to move them to my new apartment, I’m just going to keep them.

Okay, now let’s learn about some invertebrates! First, Jayson wanted to learn about a tiny invertebrate called Orthohalarachne attenuata. It doesn’t have a common name because most people will never ever encounter it, or think about it, and I kind of wish I didn’t have to think about it because it’s gross. Thanks a lot, Jayson. It’s a mite that lives in the nasal passages of seals, sea lions, and walruses. It’s incredibly common and usually doesn’t bother the seal very much, although sometimes it can cause the seal to have difficulty breathing if the infestation is heavy.

The adult mite spends its whole life anchored in the seal’s nasal passages with sharp little claws, although it can move around if it wants to. Its larvae are more active. The mite is mainly spread by seals sneezing on each other, which spreads the larvae onto another seal, and the larvae crawl into the new seal’s nose and mouth.

Unless you’re a seal or other pinniped, this might sound gross but probably doesn’t bother you too much. But consider that in 1984, a man went to the doctor when one of his eyes started hurting. The doctor found a mite attached to his eyeball, and yes, it was Orthohalarachne attenuata. The man had visited Sea World two days before he started feeling pain in his eye, and happened to be close to some walruses that were sneezing.

Luckily for pinnipeds kept in captivity in zoos that give their animals proper care, mite infestations can be treated successfully by veterinarians.

Let’s move on quickly to an invertebrate that isn’t a parasite that can get in your eyes, the ant lion! It was suggested by warblrwatchr and I’ve been wanting to cover it for a while. When I was a kid, there was a strip of soft powdery dirt under the eaves of the school gym that always had ant lions in it, and I would squat down during recess and watch to see if any ants would fall in and get caught. Sometimes this did actually happen and the resulting battle between ant and ant lion was exciting and kind of horrible to witness.

The ant lion is actually the larva of antlion lacewing, which look like a small damselfly that is mainly active at dusk. Ant lions live throughout the world, with more than 2,000 species known. Some wait for prey while hidden in leaf litter, while some hide in rock crevices and become camouflaged by lichens growing on them. Many others dig little pits in sand or soft dirt. They’re also called the doodlebug in some places, because when they’re looking for a place to dig a little pit, they make a loopy pattern in the dirt as they’re walking around.

The ant lion’s body is robust and has little backwards-pointing bristles that help it dig itself into the dirt and stay there without moving until it needs to. It waits at the bottom of the pit, hidden underground with just its long, sharp jaws showing through the dirt, until an ant or other insect falls in. The ant can’t climb out because the sides of the pit are so sharply angled that they start to cave in, sending the ant down to the bottom of the pit. If that doesn’t work, the ant lion kicks dirt at the ant so that it falls. Then the ant lion grabs the ant in its fearsome jaws and injects venom and digestive enzymes into it, and that is the end of the ant. The jaws actually have little projections that are hollow and act like horrible little straws, so that the ant lion sucks the liquefied ant insides into its digestive system.

One species of ant, the trap-jaw ant, can sometimes escape the ant lion’s pit by using its own fearsome jaws as a spring to bounce itself to safety. There are many species of trap-jaw ant that live in tropical and subtropical areas throughout much of the world, including Africa, Asia, Australia, and much of the Americas. Its long jaws can snap closed extremely quickly and with a lot of force, allowing it to kill prey, bite pieces off of food, and lots of other activities. They can also jump with their jaws, and this improves their ability to bounce right out of the ant lion pit.

The ant lion can remain in its larval stage for years, maturing slowly. It has no anus but it doesn’t expel the waste products that it can’t digest, it just stores them in its body. When it does finally pupate, it uses a lot of the waste to produce silk for its cocoon. Whatever is left over it leaves behind when it emerges from its cocoon.

The cocoons are naturally hidden underground, and when the adult antlion lacewing emerges, it digs its way to the surface and rests while its wings open. Compared to the tough little larva, the adult is delicate and not very robust. It doesn’t live very long, usually no more than a few weeks, and most species eat pollen or nectar, or maybe tiny insects. It mainly just seeks out a mate, and the female lays her eggs in soft soil. When they hatch, they build their first tiny pits and the cycle starts again. And nobody gets into anybody’s eyeballs.

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 440: Trilobites!

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Thanks to Micah for suggesting this week’s topic, the trilobite!

Further reading:

The Largest Trilobites

Stunning 3D images show anatomy of 500 million-year-old Cambrian trilobites entombed in volcanic ash

Strange Symmetries #06: Trilobite Tridents

Trilobite Ventral Structures

A typical trilobite:

Isotelus rex, the largest trilobite ever found [photo from the first link above]:

Walliserops showing off its trident [picture by TheFossilTrade – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=133758014]:

Another Walliserops individual with four prongs on its trident [photo by Daderot, CC0, via Wikimedia Commons]:

Show transcript:

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

This week we’re going to learn about an ancient animal that was incredibly successful for millions of years, until it wasn’t. It’s a topic suggested by Micah: the trilobite.

Trilobites first appear in the fossil record in the Cambrian, about 520 million years ago. They evolved separately from other arthropods so early and left no living descendants, that they’re not actually very closely related to any animals alive today. They were arthropods, though, so they’re distantly related to all other arthropods, including insects, spiders, and crustaceans.

The word trilobite means “three lobes,” which describes its basic appearance. It had a head shield, often with elaborate spikes depending on the species, and a little tail shield. In between, its body was segmented like a pillbug’s or an armadillo’s, so that it could flex without cracking its exoskeleton. Its body was also divided into three lobes running from head to tail. Its head and tail were usually rounded so that the entire animal was roughly shaped like an oval, with the head part of the oval larger than the tail part. It had legs underneath that it used to crawl around on the sea floor, burrow into sand and mud, and swim. Some species could even roll up into a ball to protect its legs and softer underside, just like a pillbug.

Because trilobites existed for at least 270 million years, there were a lot of species. Scientists have identified about 22,000 different species so far, and there were undoubtedly thousands more that we don’t know about yet. Most are about the size of a big stag beetle although some were tinier. The largest trilobite found so far lived in what is now North America, and it grew over two feet long, or more than 70 centimeters, and was 15 inches wide, or 40 cm. It’s named Isotelus rex.

I. rex had 26 pairs of legs, possibly more, and prominent eyes on the head shield. Scientists think it lived in warm, shallow ocean water like most other trilobites did, where it burrowed in the bottom and ate small animals like worms. There were probably other species of trilobite that were even bigger, we just haven’t found specimens yet that are more than fragments.

Because trilobites molted their exoskeletons the way modern crustaceans and other animals still do, we have a whole lot of fossilized exoskeletons. Fossilized legs, antennae, and other body parts are much rarer, and preserved soft body parts are the rarest of all. We know that some trilobite species had gills on the legs, some had hairlike structures on the legs, and many had compound eyes. A specimen with preserved eggs inside was also found recently.

Some incredibly detailed trilobite fossils have been found in Morocco, including details like the mouth and digestive tract. The detail comes from volcanic ash that fell into shallow coastal water around half a billion years ago. The water cooled the ash enough that when it fell onto the trilobites living in the water, it didn’t burn them. It did suffocate them, though, since so much ash fell that the ocean was more ash than water.

The ash was soft and as fine as powder, and it covered the trilobites and protected their bodies from potential damage, while also preserving the body details as they fossilized over millions of years. The fossils were discovered in 2015, about 509 million years after the trilobites died, and are still being studied.

Two species of trilobite have been found at this Morocco site, and the team is using non-invasive technology to study the preserved insides in one exceptionally preserved specimen. Its entire digestive system is intact, probably because the poor trilobite ended up swallowing a lot of ash before it died. The ash kept the soft tissues from decomposing.

Some trilobites had spines growing from their head shields and even from the rest of the exoskeleton. Scientists think these may have helped protect the animals from being eaten, but they might also have helped them navigate more easily in the water without getting flipped over by currents. One genus of trilobite, Walliserops, even had a structure sticking out from the front of its head called a trident.

The trident grew forward and slightly upward from the head, then split into three prongs. Scientists aren’t sure what it was for, but suggest that it acted as a nose spike like some modern beetles have, which allowed trilobites to fight each other for resources or mates. The tridents weren’t completely symmetrical, and one individual has even been found with a four-pronged trident. (I guess you would call that a quadrent.) Some species had long tridents, some short, but there’s no evidence that only males or only females had them.

Electron microscopes and other modern imaging technology have allowed scientists to learn more about what the trilobite looked like when it was alive. This includes some hints about different species’ coloration and markings. Most trilobites had good vision and were probably as colorful as modern crustaceans. Some rare trilobite fossils show microscopic traces of spots and stripes. One species studied may have had a brown stripe that faded to white along the edges of the body.

All trilobites went extinct at the end of the Permian, about 250 million years ago, during the extinction event called the Great Dying. We talked about it in detail in episode 227 so I won’t go over its causes and effects again except to say that an estimated 95% of all marine animals went extinct during that event. The Great Dying ended the trilobite’s successful 270 million year run on this amazing planet.

When I was little, I found trilobites fascinating. They were so common for so long, and then they were gone. I’ve always wondered if some trilobites survived the Great Dying and were still alive in the deep sea. I’m not the only one who’s wondered that, so let’s talk a little more about why the trilobites went extinct and how some of them might have survived.

Almost all trilobites we know of lived in shallow coastal water. We have trilobite tracks of an ancient low tide shore, which tells us that at least some species could leave the water and venture onto land occasionally, possibly the first animals on earth to do so. Coastal water is well oxygenated and we know trilobites had trouble surviving anoxic events, when the water where they lived had much less oxygen than usual. Anoxic events are actually what led to the Great Dying, but it wasn’t the first time the world’s oceans became less oxygenated. It happened in earlier extinction events too during the Devonian, around 372 and 359 million years ago, and each time many species and genera of trilobites went extinct. The trilobite was already in decline when the Great Dying occurred, with only a handful of genera left, and the extinction event finished them off once and for all according to the fossil record.

But we do know of a few species of trilobite that were adapted to the deep sea. Deep-sea animals have to evolve to be tolerant of low-oxygen conditions. The deep sea is also very little known by humans. It’s possible, even if it’s unlikely, that deep-sea trilobites survived the Great Dying and that their descendants are still around, unknown to science.

One interesting note, and an ongoing mystery about trilobites, is that while we know they were arthropods, we don’t actually know which branch of the phylum Arthropoda they’re most related to. That’s because there are no ancestral versions of the trilobite that have ever been found. When they appear in the fossil record, they’re already recognizably trilobites. It’s possible that the ancestral forms didn’t have exoskeletons that were likely to fossilize, or that we just haven’t found the right fossil bed yet. Until we learn more, it’ll remain a mystery.

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 437: Updates 8 and the Nutria

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Thanks to Nicholas, Måns, Warblrwatchr, Llewelly, and Emerson this week, in our yearly updates episode!

Further reading:

An Early Cretaceous Tribosphenic Mammal and Metatherian Evolution

Guam’s invasive tree snakes loop themselves into lassos to reach their feathered prey

Rhythmically trained sea lion returns for an encore — and performs as well as humans

Scientists Solve Mystery of Brown Giant Pandas

Elephant turns a hose into a sophisticated showering tool

New name for one of the world’s rarest rhinoceroses

Antarctica’s only native insect’s unique survival mechanism

Komodo dragons have iron-coated teeth to rip apart their prey

The nutria has really orange teeth:

Show transcript:

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

This week is our annual updates episode, and we’ll also learn about an animal suggested by Emerson. But first, we have some corrections!

Nicholas shared a paper with me that indicates that marsupials actually evolved in what is now Asia, with marsupial ancestors discovered in China. They spread into North America later. So I’ve been getting that wrong over many episodes, over several years.

Måns shared a correction from an older episode where I mentioned that humans can’t get pregnant while breastfeeding a baby. I’ve heard this all my life but it turns out it’s not true. It is true that a woman’s fertility cycle is suppressed after giving birth, but it’s not related to breastfeeding. Some women can become pregnant again only a few months after giving birth, while others can’t get pregnant again for a few years. It depends on the individual. That’s important, since the myth is so widespread that many women get pregnant by accident thinking they can’t since they’re still feeding a baby.

Warblrwatchr commented on the ultraviolet episode and mentioned that cats can see ultraviolet, which is useful to them because mouse urine glows in UV light.

Finally, Llewelly pointed out that in episode 416, I didn’t mention that fire ant venom isn’t delivered when the ant bites someone. The ant bites with its mandibles to hold on, then uses the stinger on its back end to sting repeatedly.

Now, let’s dive into some updates about animals we’ve talked about in past episodes. As usual, I don’t try to give an update on every single animal, because we’d be here all week if I did. I just chose interesting studies that caught my eye.

In episode 402, we talked about snakes that travel in unusual ways, like sidewinders. Even though I had a note to myself to talk about the brown tree snake in that episode, I completely forgot. The brown tree snake is native to parts of coastal Australia and many islands around Indonesia and Papua New Guinea. It’s not native to Guam, which is an island in the western Pacific, way far away from the brown tree snake’s home. But in the late 1940s, some brown tree snakes made their way to Guam in cargo ships and have become invasive since then.

The brown tree snake can grow up to six and a half feet long, or 2 meters, and is nocturnal, aggressive, and venomous. It’s not typically a danger to adults, but its venom can be dangerous to children and pets. The government employs trained dogs to find the snakes so they can be removed, and this has worked so well that brown tree snake population is declining rapidly on the island. But that hasn’t stopped the snake from driving many native animals to extinction in the last 75 years, especially birds.

One of the things scientists did in Guam to try and protect the native birds was to place smooth poles around the island so birds could nest on top but snakes couldn’t climb up to eat the eggs and chicks. But before long, the snakes had figured out a way to climb the poles, a method never before documented in any snake.

To climb a pole, the snake wraps its body around it, with the head overlapping the tail. Then it sort of scoots itself up the pole with tiny motions of its spine, a slow, difficult process that takes a lot of energy. Tests of captured brown tree snakes afterwards showed that not all snakes are willing or able to climb poles this way. Scientists think the brown tree snake evolved this method of movement to climb smooth-trunked trees in its native habitat. They also suspect some other species of snake can do the same.

Way back in episode 23 we talked about musical animals, including how some species can recognize and react to a rhythmic beat while most can’t. Sea lions are really good at it, especially a sea lion named Ronan.

Ronan was rescued in 2009 when she was a young sea lion suffering from malnutrition, wandering down a highway in California. She was determined to be non-releasable after she recovered, so she’s been a member of the Pinniped Lab in the University of California – Santa Cruz ever since, where she participates in activities that help scientists study sea lions. The rhythm studies are only one of the things she does, and only occasionally. The scientists put on a metronome and she bobs her head to the beat while they film her in ultra-slow motion.

The latest study was published in May of 2025. Ronan is 16 years old now and in her prime, so it’s not surprising that she performed even better than her last tests when she was still quite young. The study determined that not only does Ronan hit the beat right on time, she’s actually better at it than a human a lot of the time. She hits the beat within 15 milliseconds. When you blink your eye, it takes 150 milliseconds. If only she had hands, she’d be the best drummer ever!

The greatest thing about this process is that Ronan enjoys it. She’s rewarded with fish after a training session, and if she doesn’t feel like doing an activity, she doesn’t have to.

Back in episode 220, we talked about the giant panda, especially the mysterious Qinling panda that’s brown and tan instead of black and white. A study published in March of 2024 looked into the genetics of this unusual coat color and determined that it was a natural genetic mutation that doesn’t make the animals unhealthy, meaning it probably isn’t a result of inbreeding.

We talk occasionally about tool use in animals, especially in birds like crows and parrots, and in primates like chimpanzees. But a study published in November of 2024 detailed an elephant in the Berlin Zoo that uses a water hose to shower.

You may not think that’s a big deal, but the elephant in question, named Mary, uses the hose the way a human would to shower off. She holds the hose with her trunk just behind the nozzle, then moves it around and shifts her body to make sure she gets water everywhere she wants. She has to sling the hose backwards to clean her back, and when researchers gave her a heavier hose that she couldn’t move around as easily, she didn’t bother with it but just used her own trunk to spray water on herself.

Even more interesting, another elephant, named Anchali, who doesn’t get along with Mary, will interfere with the hose while Mary is using it. She lifts part of the hose to kink it and stop the water from flowing. Sometimes she even steps on the hose to stop the water, something the elephants have been trained not to do since zookeepers use hoses to clean out the enclosures. Anchali only steps on a hose if Mary is using it.

This is the first time researchers have studied a water hose as tool use, but it makes sense for elephants to understand how to use a hose, since they have a built-in hose on their faces.

We talked about the rhinoceros in episode 346, and more recently in the narwhals and unicorns episode. A study published in March of 2025 suggested that the Javan rhino should be classified as a new species of rhino in its own genus. The Javan rhino is incredibly rare, with only about 60 individuals alive in the world, all of them living in the wild in one part of Java. The Javan rhino is also called the Sundaic rhinoceros, and it’s been considered a close relation of the Indian rhinoceros. It’s smaller than the Indian rhino and most Javan rhino females either don’t have a horn at all or only have a big bump on the nose instead of a real horn.

The Javan rhino is so rare that we don’t really know much about it. The new study determined that there are big enough differences between the Javan rhino and the Indian rhino, in their skeletons, skin, diet, behavior, and fossil remains, that they should be placed in separate genera. The proposed new name for the Javan rhino is Eurhinoceros sondaicus instead of Rhinoceros sondaicus.

The only insect native to Antarctica is the Antarctic midge, which we mentioned in episode 221 but haven’t really talked about. It’s a flightless insect that can grow up to 6 mm long, and it’s the only insect that lives year-round in Antarctica. It’s only been found on the peninsula on the northwestern side of the continent.

Every animal that lives in Antarctica is considered an extremophile, and this little midge has some remarkable adaptations to its harsh environment. Its body contains compounds that minimize the amount of ice that forms in its body when the temperature plunges. It’s so well adapted to cold weather that it actually can’t survive if the temperature gets much above freezing. It eats decaying vegetation, algae, microorganisms, and other tiny food in its larval stages, but doesn’t eat at all as an adult.

The midge spends most of its life as a larva, only metamorphosing into its adult form after two winters. During its first winter it enters a dormant phase called quiescence, but as soon as the weather warms, it can resume development. It enters another dormant phase called obligate diapause for its second winter, where it pupates as soon as the weather gets cold. When summer arrives, all the midges emerge as adults at the same time, which allows them to find mates and lay eggs before dying a few days later.

The female midge lays her eggs and deposits a jelly-like protein on top of them. The jelly acts as antifreeze and keeps the eggs from drying out, and when the eggs hatch, the babies can eat the jelly.

In episode 384, we talked about the Komodo dragon, and only a month or so after that, and right after the 2024 updates episode, a new study was released about Komodo dragon teeth. It turns out that the Komodo dragon has teeth that are tipped with iron, which helps keep them incredibly sharp but also strong. As if Komodo dragons weren’t already scary enough, now we know they have metal teeth!

Many animals incorporate iron in their teeth, especially rodents, which causes some animals to have orange or partially orange teeth. In the Komodo dragon, the iron is incorporated into the tooth’s enamel coating, but only on the tips of the teeth. Since Komodo dragons have serrated teeth, that’s a lot of very sharp points.

There’s no way currently to test fossilized teeth to see if they once contained iron, especially since the iron would most likely be deposited in the tooth coating, the way it is for animals living today, not in the tooth itself. But because the Komodo dragon has teeth that are very similar in many ways to the teeth of meat-eating dinosaurs, scientists think some dinosaurs may have had iron in their teeth too.

And that brings us to the nutria, an animal suggested by Emerson. Emerson likes the nutria because of its orange teeth, and hopefully you can guess why its teeth are orange.

The nutria is also called the coypu, and it’s a rodent native to South America. In Spanish the word nutria means otter, so in South America it’s almost exclusively called the coypu, and the name coypu is becoming more popular in other languages too. It’s been introduced to other parts of the world as a fur animal, and it has become invasive in parts of Europe, Japan, New Zealand, and the United States.

The nutria is a semi-aquatic rodent that looks like a muskrat but is much bigger, up to two feet long, or 64 cm, not counting its tail. It also kind of looks like a beaver but is smaller. If you’re not sure which of these three animals you’re looking at, since they’re so similar, the easiest way to tell them apart is to look at their tails. The beaver has a famously flattened paddle-like tail, the muskrat’s tail is flattened side to side to act as a rudder, and the nutria’s tail is just plain old round. The nutria also has a white muzzle and chin, and magnificent white whiskers.

The nutria mostly eats water plants and is mostly active in the twilight. While it usually lives around slow-moving streams and shallow lakes, it will also tolerate saltwater wetlands. Wild nutrias are generally dark brown, but ones bred for their fur are often blond or even white.

The nutria digs large dens with the entrance usually underwater, but the nesting chamber inside is dry. It also digs for roots. This can cause a lot of damage to levees and riverbanks, which is why the nutria is so destructive as an invasive animal. It will also eat people’s gardens and commercial crops like rice and alfalfa.

One interesting thing about the nutria is that the female has teats that are high up on her sides, which allows her babies to nurse even when they’re all in the water.

The nutria’s big incisor teeth are bright orange, as we mentioned before. This is indeed because of the iron in the enamel that strengthens the teeth. Like other rodents, the nutria’s incisors grow throughout its life and are continually worn down as it chews tough plants. A nutria eats about 25% of its weight in plants every single day. That’s almost as much as me and pizza.

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 432: The Fossa and Other Animals of Madagascar

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This week we learn about the fossa and a few other animals of Madagascar, a suggestion by Pranav!

Further reading:

The stories people tell, and how they can contribute to our understanding of megafaunal decline and extinction in Madagascar

The fossa!

The votsotsa is a rodent, not a rabbit! [photo by Andrey Giljov – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=113271739]:

The golden mantella frog is sometimes golden, but sometimes red:

The nano-chameleon may be the smallest reptile in the world:

Show transcript:

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

This week we have a very old Pranav suggestion, animals of Madagascar!

The island country of Madagascar is off the southeastern coast of Africa. About 88 million years ago, it broke off from every other landmass in the world, specifically the supercontinent Gondwana. The continent we now call Africa separated from Gondwana even earlier, around 165 million years ago. Madagascar is the fourth largest island in the world and even though it’s relatively close to Africa these days, many of its animals and plants are much different from those in Africa and other parts of the world because they’ve been evolving separately for 88 million years.

But at various times in the past, some animals from Africa were able to reach Madagascar. We’re still not completely sure how this happened. Madagascar is 250 miles away from Africa, or 400 kilometers, and these days the prevailing ocean currents push floating debris away from the island. In the past, though, the currents might have been different and some animals could have arrived on floating debris washed out to sea during storms. During times when the ocean levels were overall lower, islands that are underwater now might have been above the surface and allowed animals to travel from island to island until they reached Madagascar.

We’re not sure when the first humans visited Madagascar, but it was at least 2,500 years ago and possibly as much as 9,500 years ago or even earlier. It’s likely that hunting parties would travel to Madagascar and stay there for a while, then return home with lots of food, but eventually people decided it would be a nice place to live. By 1,500 years ago people were definitely living on the island.

Let’s start with the fossa, an animal we’ve only talked about on the podcast once before, and then only in passing. It resembles a type of cat about the size of a cougar, although its legs are short in comparison to a similarly-sized cat. Its tail is almost as long as its body, and if you include its tail, it can grow around five feet long, or 1.5 meters. It’s reddish-brown with a paler belly. Its head is small with a short muzzle, rounded ears, and big eyes.

But the fossa isn’t a felid. It resembles a really big mustelid in many ways, especially a mongoose, and some studies suggest it’s most closely related to the mongoose. Really, though, it’s not closely related to anything living today. It spends a lot of time in trees, where it uses its long tail to help it balance. It even has semi-retractable claws. It eats lemurs and other mammals, birds, insects, crabs, lizards, and even fruit.

There used to be an even bigger fossa called the giant fossa, although we don’t know much about it. We only know about it from some subfossil remains found in caves. We’re not sure how big it was compared to the fossa living today, but it was definitely bigger and stronger and might have grown 7 feet long including its tail, or a little over 2 meters. There used to be much bigger lemurs living on Madagascar that have also gone extinct, so the giant fossa probably evolved to prey on them.

Most scientists estimate that the giant fossa went extinct at least 700 years ago, but some think it might have survived in remote areas of Madagascar until much more recently. There are even modern sightings of unusually large fossas, sometimes reported as twice the size of a regular fossa.

One interesting thing about the fossa is that its anus is hidden most of the time by a little fold of skin called an anal pouch, sort of like built-in underwear.

One animal most people outside of Madagascar have never heard of is the votsotsa, also called the Malagascar giant rat or the giant jumping rat since it’s a rodent that is especially known for its ability to jump. It actually looks a lot like a rabbit in size and shape, including its long ears, but it has a long tail. It’s gray or brown in color and grows about a foot long, or 30 cm, with a tail that can be up to 10 inches long, or 25 cm.

The votsotsa mates for life and both parents raise the single baby the mother gives birth to once or twice a year. It’s a nocturnal animal that spends the day in its burrow, which can be as much as 16 feet long, or 5 meters, with multiple exits. It eats nuts and seeds, fruit, leaves, and other plant material, along with insects and other small animals.

Lots of bats live on Madagascar, including the Madagascar flying fox. It’s a fruit-eating bat that’s brown or golden-brown in color with gray or black wings, and it’s the biggest bat native to the island. It has a wingspan of more than four feet across, or 125 cm. Like other species of flying fox, it lives in colonies of up to a thousand individuals that roost together in trees during the day. It mostly forages in the evenings, searching for fruit like figs. It eats flowers and sometimes leaves as well as fruit, and it may even be a pollinator for the kapok tree’s flowers.

Naturally, Madagascar also has a lot of reptiles, amphibians, and other non-mammalian animals. For instance, the golden mantella frog. It’s a little frog that’s only found in a few small areas, and measures around 20 millimeters long snout to vent. Some individuals are golden yellow while others are bright orange or red. As you may remember from our many previous episodes about frogs, such bright colors act as a warning to potential predators, to let them know that the frog is toxic. It absorbs toxins from some of the insects it eats. It’s active during the day in summertime, and in winter it spends most of the time hiding and doing nothing, which is the best way to spend the winter.

There are also lots of chameleons on Madagascar, including one called the nano-chameleon. It gets its name from its size, which is extremely small. It’s the smallest chameleon in the world, only 29 mm long at the very most, which is barely more than an inch long. Males are smaller than females, usually around 22 mm. It was described in 2021 and is brownish-grey with pale yellow or yellow-brown markings. Chameleons are famous for changing color, but the nano-chameleon doesn’t. It also mostly lives on the ground, where it hunts tiny insects and other invertebrates. Some scientists think it may be the smallest reptile in the world.

The female Darwin’s bark spider is about the same size as the female nano-chameleon, if you don’t count the spider’s legs. Males are much smaller. Darwin’s bark spider is a type of orb-weaver, which is the kind of spider that spins large webs that look like Halloween decorations. It was described in 2010 after first being discovered by scientists in 2009, which is surprising because it builds the largest orb webs known. Some webs can be over 30 square feet in size, or 2.8 square meters.

The silk is the strongest biological material ever studied, twice as strong as any other spider silk studied. The spider builds its web over water, because it eats a lot of mayflies and other insects that are attracted to water. It also eats a lot of dragonflies, and dragonflies are quite large and strong insects that don’t usually get caught in spiderwebs.

The people of Madagascar are considered very poor compared to other countries, after almost a century of French colonization and the resulting instability after it regained independence in 1960. A lot of animals that were once considered to be forbidden to bother, for religious and cultural reasons, now end up killed so people can eat them instead of starving. Mining and slash-and-burn agriculture has also contributed to pollution, habitat loss, and other factors that aren’t good for the animals of Madagascar or its people. Luckily, eco-tourism, where people visit the island to experience its beauty and see animals and plants found nowhere else on earth, is becoming more common. Hopefully that will help improve conditions for the people who live there and for the animals too.

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 427: The Other Cephalopods

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Further reading:

Reconstructing fossil cephalopods: Endoceras

Retro vs Modern #17: Ammonites

Hammering Away at Hamites

An endocerid [picture by Entelognathus – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=111981757]:

An ammonite fossil:

A hamite ammonoid that looks a lot like a paperclip [picture by Hectonichus – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=34882102]:

Show transcript:

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

When you think about cephalopods, if that’s a word you know, you probably think of octopuses and squid, maybe cuttlefish. But those aren’t the only cephalopods, and in particular in the past, there used to be even more cephalopods that are even weirder than the ones we have today.

Cephalopods are in the family Mollusca along with snails and clams, and many other animals. The first ancestral cephalopods date back to the Cambrian, and naturally we don’t know a whole lot about them since that was around 500 million years ago. We have fossilized shells that were only a few centimeters long at most, although none of the specimens we’ve found are complete. By about 475 million years ago, these early cephalopod ancestors had mostly died out but had given rise to some amazing animals called Endocerids.

Endocerids had shells that were mostly cone-shaped, like one of those pointy-ended ice cream cones but mostly larger and not as tasty. Most were pretty small, usually only a few feet long, or less than a meter, but some were really big. The largest Endoceras giganteum fossil we have is just under 10 feet long, or 3 meters, and it isn’t complete. Some scientists estimate that it might have been almost 19 feet long, or about 5.75 meters, when it was alive.

But that’s just the long, conical shell. What did the animal that lived in the shell look like? We don’t know, but scientists speculate that it had a squid-like body. The head and arms were outside of the shell’s opening, while the main part of the body was protected by the front part of the shell. We know it had arms because we have arm impressions in sections of fossilized sea floor that show ten arms that are all about the same length. We don’t know if the arms had suckers the way many modern cephalopods do, and some scientists suggest it had ridges on the undersides of the arms that helped it grab prey, the way modern nautiluses do. It also had a hood-shaped structure on top of its head called an operculum, which is also seen in nautiluses. This probably allowed Endoceras giganteum to pull its head and arms into its shell and use the operculum to block the shell’s entrance.

We don’t know what colors the shells were, but some specimens seem to show a mottled or spotted pattern. The interior of Endoceras giganteum’s shell was made up of chambers, some of which were filled with calcium deposits that helped balance the body weight, so the animal didn’t have trouble dragging it around.

3D models of the shells show that they could easily stick straight up in the water, but we also have trace fossils that show drag marks of the shell through sediment. Scientists think Endoceras was mainly an ambush predator, sitting quietly until a small animal got too close. Then it would grab it with its arms. It could also crawl around to find a better spot to hunt, and younger individuals that had smaller shells were probably a lot more active.

We talked about ammonites way back in episode 86. Ammonites were really common in the fossil record for hundreds of millions of years, only going extinct at the same time as the dinosaurs. Some ammonites lived at the bottom of the ocean in shallow water, but many swam or floated throughout the ocean. Many ammonite fossils look like snail shells, but the shell contains sections inside called chambers. The largest chamber, at the end of the shell, was for the ammonite’s body, except for a thin tube that extended through the smaller inner chambers, which allowed the animal to pump water or air into and out of the chambers in order to make itself more or less buoyant in the water.

While many ammonites were no larger than modern snails, many others were bigger than your hand, sometimes twice the size of your hand even if you have really big hands. But during the Jurassic and part of the Cretaceous, some ammonites got even bigger. One species grew almost two feet across, or 53 cm. Another grew some 4 ½ feet across, or 137 cm, and one species grew as much as 6 ½ feet across, or 2 meters. It was found in Germany in 1895 and dates to about 78 million years ago–and it wasn’t actually a complete fossil. Researchers estimate that in life it would have been something like 8 and a half feet across, or 2.55 meters.

Ammonites look a lot like a modern cephalopod called the nautilus, so much so that I thought for a long time that they were the same animal and they were all extinct. Imagine my surprise when I started researching episode 86! But although nautiluses look similar, it turns out they’re not all that closely related to ammonites. Ammonites were probably more closely related to squid, octopuses, and cuttlefish than to modern nautiluses.

Until very recently, we had no idea what the ammonite’s body looked like, just its shell. Scientists hypothesized that they had ten arms. Then, in 2021, three years after episode 86 because I have been making this podcast for a really long time, scientists found a partial fossil of an ammonite’s body. That was followed by two more discoveries of ammonite bodies, so we know a lot more about it now. We now know that ammonites resembled squid with shells a lot more than they resembled nautiluses. We still don’t know how many arms they had, but they do appear to have had two feeding tentacles like squid have, with hook-like structures that would help the ammonite hold onto wiggly prey.

Not all ammonoids had shells that resembled a snail’s spiral shell. Heteromorph ammonites had a wide variety of shell shapes. They were extremely common starting around 200 million years ago, so common that they’re used as index fossils to help scientists determine how old a particular segment of rock is. Some of the shells look a lot like ram horns, loosely coiled with ribs on the upper surface, while others were almost straight.

Baculites are a genus of ammonoid that had straight or only gently curved shells, sort of like Endocerids but living about 300 million years later and only very distantly related to them. The longest baculite shell found so far was about 6 and a half feet long, or 2 meters. Nipponites were a more complicated shape, as though a ram’s horn somehow got twisted up and crumpled into a lopsided ball. Turrilites grew in a tight spiral but with the coils on top of each other like a spiral staircase. But the best to my mind are the hamites, because some of them had shells shaped like paper clips.

We don’t know much about heteromorph ammonites, and scientists aren’t even sure how they moved around and found food. Their shell shapes would have made them slow swimmers. Many scientists now think they floated around in the water and caught tiny food as they encountered it. They even survived the end-cretaceous extinction event, although they only lived for about half a million years afterwards.

Let’s finish with a living animal, the Dana octopus squid. It’s a squid but as an adult it doesn’t have the two feeding tentacles that most squid have. It just has eight arms, which is why it’s called the octopus squid. The Dana octopus squid is a deep-sea animal that can grow quite large, although it doesn’t have very long arms. The largest specimen measured was 7 and a half feet long including its arms, or 2.3 meters, but most of that length was the mantle. The arms are only about two feet long, or 61 cm.

Because it lives in deep water, we don’t know very much about the Dana octopus squid. We know it’s eaten by sperm whales, sharks, and other large animals, and occasionally part of a dead one will wash ashore. In 2005 a team of Japanese researchers filmed a living Dana octopus squid in deep water and discovered something surprising. The undersides of the squid’s arms contain photophores that can emit light, which is pretty common in deep-sea animals. The squid’s photophores are the largest known, and now we know why.

The video showed the squid attacking the bait, and before it did, its photophores flashed extremely bright. It was so bright that the scientists think the light disorients the squid’s prey as well as allowing the squid to get a good look at where its prey is. Even better, young Dana octopus squid have been observed flashing their photophores at large predators and swimming toward them in a mock attack, startling and even scaring away a much larger animal.

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!