Category Archives: invertebrates

Episode 462: Cryptic Coloration

Posted on by

Podcast: Play in new window | Download (Duration: 17:07 — 19.4MB)

Subscribe: RSS | More

Thanks to Måns, Sam, Owen and Askel for this week’s suggestions!

Further reading:

Shingleback Lizard

What controls the colour of the common mānuka stick insect?

The mossy leaf-tailed gecko has skin flaps that hide its shadow. There’s a lizard in this photo, I swear! [photo by Charles J. Sharp – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=92125100]:

A shingleback lizard, pretending it has two heads:

The beautiful wood nymph is a beautiful moth but also it looks like a bird poop:

The Indian stick insect (photo by Ryan K Perry, found on this page):

The buff tip moth mimics a broken-off stick. This person has a whole handful of them:

A cuttlefish can change colors quickly [photo by Σ64 – Own work, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=77733806]:

Show transcript:

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

This week we’re going to talk about a few types of camouflage, a suggestion by Måns, and we’ll also talk about some camouflaged animals suggested by Sam, Owen and Aksel, Dylan, and Nina.

There are lots of types of camouflage, not all of it visual in nature. Back in episode 191 we talked about some toxic moths that generate high-pitched clicks that bats hear, recognize, and avoid. Naturally, some non-toxic moths also generate the same sounds to mimic the toxic moths.

Måns specifically suggested cryptic coloration, also called crypsis. It’s a type of camouflage that allows an animal to blend into their surroundings, which can involve multiple methods.

Some animals have cryptic coloration mainly along the edges of the body, to defeat a skill many predators use called edge detection. A lot of amphibians and reptiles have patches surrounded by an outline, with dark patches having a darker outline and light patches having a lighter outline. This acts as disruptive camouflage, hiding the outline of an animal’s body as it moves around. Some animals take this camouflage even further, with a way to hide their own shadow.

This is the case with the mossy leaf-tailed gecko, which is native to the forests of eastern Madagascar. It can grow up to 8 inches long, or 20 cm, not counting its tail, and it’s nocturnal. Its tail is flat and broad, sort of shaped like a leaf, but it doesn’t disguise itself as a leaf.

The mossy leaf-tailed gecko has a complicated gray and brown pattern that looks like tree bark, and it can change its coloration a little bit to help it blend in even more. At night it’s well hidden in tree branches as it climbs around looking for insects, but in the day it needs to hide really well to avoid becoming some other animal’s snack while it’s sleeping.

It does this by finding a comfortable branch and flattening its body and tail against it so that it just looks like another part of the branch. But to make it even more hidden, it has a flap of skin along its sides that wraps even farther around the branch. Not only do these skin flaps hide its edges, it hides its shadow, since the flaps are really flat and there’s no curved edge of a lizard belly pressed against a branch that a predator might notice.

The most common kind of cryptic coloration is called countershading, and it’s so common that you might not even have noticed it although you see it almost every time you see a fish, amphibian, reptile, and many birds and mammals. Countershading is an animal that’s darker on top and lighter underneath, like a brown mouse with a white belly. It’s even found in some insects and other invertebrates.

Countershading is another way to hide a shadow. If a dolphin, for instance, was gray all over, its underside would look darker because of shadows, since sunlight shines down from the sky and makes shadows underneath the body. That would make its body shape look rounder, meaning it stands out more and a predator would notice it more easily. But most dolphins are pale gray or even white underneath. There’s still a shadow, but it’s no longer darker than the rest of the body. The lighter colored underside makes the shadow paler, and as a result, from a distance the dolphin looks almost the same shade all over, which makes it appear flat and the edges of its body harder to see. We even know that some dinosaurs were countershaded, with lighter colored bellies.

Countershading is so common in animals that it’s almost impossible to pick one example. Dylan suggested we learn about the shingleback lizard, an amazing animal found in many parts of Australia. It’s also called the stumpy-tailed lizard, the bobtail lizard, or the two-headed lizard. All three of those names refer to the animal’s tail, which is short and fat and actually looks like a second head. This is an example of automimicry, similar to animals that have markings that look like eyes. The lizard is brown with darker and lighter speckles and it sometimes has yellow spots too. Its belly is pale with dark spots. Its scales are large and overlap each other, and its eyes are tiny, like little black beads. It grows about a foot long, or 30 cm.

The shingleback lives in arid and desert areas, and its tough skin and overlapping scales help reduce water loss. It eats snails, insects, flowers, and other small animals and plants. When threatened, it will open its mouth wide and stick out its large, dark blue tongue. It is an impressively blue, impressively big tongue, and the inside of the shingleback’s mouth is bright pink, so the lizard has a chance to escape while its predator is startled and wondering if the lizard is dangerous. The shingleback can give a painful bite, although it’s not venomous.

The shingleback mates for life, and the female gives birth to two or three live young every year instead of laying eggs. In many reptiles that give birth to live young, the eggs basically remain in the mother’s body until they hatch, and then she gives birth. But in the shingleback’s case, her babies develop in placentas in a process very similar in many ways to placental mammals. The babies eat the placenta after they’re born, giving them a quick first meal, and they’re born ready to take care of themselves.

Sam suggested we talk about animals that can be confused with inanimate objects, which is a type of camouflage referred to as mimicry. Mimicry of all kinds is a really common type of camouflage, like all those harmless insects that have yellow and black stripes to mimic bees and wasps that can sting.

My favorite inanimate object mimic is a moth we talked about in episode 191, the beautiful wood nymph of eastern North America. It has a wingspan of 1.8 inches, or 4.6 cm, and it is indeed a beautiful little moth. Its front wings are mostly white with brown along the edges and a few brown and yellow spots, while the rear wings are a soft yellow-brown with a narrow brown edge. It has furry legs that are white with black tips. But when the moth folds its wings to rest, suddenly those pretty markings make it look exactly like a bird dropping. It even stretches out its front legs so they resemble a little splatter on the edge of the poop.

If you think about it, it makes sense that a tiny animal like an insect would want to resemble something common in its environment that’s also not eaten by very many other animals. For instance, a stick.

Owen and Aksel wanted to learn more about the walking stick, since it’s been a long time since we talked about it, episode 93. Walking stick insects are also called stick insects or phasmids. When I was a kid I was terrified of the whole idea of a stick insect, although I don’t know why. I think I thought one day I’d climb a tree and discover that some of those sticks were not actually part of the tree. I guess I spent a lot of time climbing trees, but I never actually saw a walking stick insect. Maybe that’s because they were so well camouflaged that I thought they were sticks!

Walking sticks live in trees and bushes, naturally, especially in warm areas, but they’re found on every continent except Antarctica. They’re long, thin insects with long, thin legs and they really do look like sticks. Some are green, some are brown or gray, and many have little patterns, projections, and ridges that make them look even more like real sticks. They’re closely related to another type of phasmid called a leaf insect, which as you may have already guessed, mimics a leaf. All phasmids eat leaves and other plant material and most are nocturnal.

Some phasmids can even change colors to help blend in with their background. The Indian stick insect, which is indeed found in southern India although it’s been introduced in many other parts of the world and is considered invasive in some places, grows up to about 4 inches long, or 10 cm. It’s usually brown, but it can change its color in response to light levels by moving pigment granules in its cuticle that absorb and scatter light. The Indian stick insect has many other ways to hide in plain sight. If it feels threatened, it will stretch out with its rear legs folded flat against its body and its front pair of legs stretched forward to make it look even longer. It will stay perfectly stiff even if someone picks it up, but if it thinks it’s in danger, it will spread its front legs to show a patch of red at the base of the legs. This can startle or frighten a potential predator long enough to let the stick insect get away.

One interesting thing about the Indian stick insect is that almost all individuals are females. Females don’t need to mate with a male to reproduce. The female’s babies are little clones of herself, and she drops an egg every so often onto the ground. It looks like a tiny seed, and ants think it’s a seed and will collect it and take it back to the nest to be stored for later. The egg is then protected until it hatches, when the larval insect leaves the ant nest and finds a tree or bush to hide in.

The buff tip moth also looks like a twig or branch when its wings are folded, but not in the same way the walking stick insect does. It looks like a broken-off branch instead. It’s a fairly large moth with a wingspan more than 2 and a half inches across, or 7 cm, and its wings are mostly gray with a rounded buff patch at the end. The end of its abdomen is buff too, so that it looks like the inside part of a tree branch, that’s paler than the bark. It lives throughout much of Europe and Asia, and different populations look slightly different because they’ve evolved to resemble the branches of different species of tree.

Let’s finish with Nina’s suggestion, about an animal that can change colors really fast to blend in with its background. That’s the cuttlefish, and Nina wanted to know how it changes colors so fast, and while we’re at it, why octopuses are so flexible.

The cuttlefish is a cephalopod, closely related to octopuses and squid, but is quite small in comparison. It has eight arms and two feeding tentacles, just like the squid, but its arms are really small in comparison to its mantle. There are over 100 species known so far, most of which are small enough to fit in the palm of your hand. But unlike the squid or the octopus, the cuttlefish has an internal structure called the cuttlebone. It’s not a bone at all but a modified shell, which is your reminder that cephalopods are mollusks and are distantly related to clams, snails, and many other animals that have shells. The cuttlebone helps the cuttlefish stay buoyant without effort, and it also incidentally makes the body a little more structured than its squid and octopus cousins.

Octopuses are flexible because they have no bones. Basically the only hard structure in an octopus is its beak. A cephalopod’s mouth is in the middle of its arms, so it’s usually hidden from view. Way back in episode 142 we talked about how octopus muscles work, so let’s revisit that briefly. In animals with bones, muscles are attached to the bones. But octopuses don’t have bones.

The octopus’s muscles are structured differently than muscles in animals with bones. Our muscles are made up of fibers that contract in one direction. Let’s say you pick up something heavy. To do so, you contract the fibers in some muscles to shorten them, which makes the bone they’re attached to move. Then, when you push a heavy door closed, you contract other muscles and at the same time you relax the muscles you used to pick up something heavy. This pulls the arm bone in the other direction.

But in the octopus, the fibers in its muscles run in three directions. When one set of fibers contracts, the other two tighten against each other and form a hard surface for the contracted fibers to move. So they’re muscles that also sort of act like bones. It’s called a muscular hydrostat, and it actually can result in muscle movements much more precise than muscle movements where a bone is involved.

So, if you combine the octopus’s strong, precise muscle movements with its general lack of hard structures, you get a very flexible animal. Basically an octopus can squish itself through extremely small openings, as long as its beak will fit through. This can make it really hard to keep an octopus in captivity, because in addition to being flexible and squishy, the octopus is also really intelligent. It can survive for short periods of time out of the water, and it can figure out how to open its enclosure and get out to explore, or just escape.

But, back to the cuttlefish, which is small and needs to hide from predators. Like other cephalopods, the cuttlefish can change color and pattern in less than a second, and can even change the texture of its skin if it wants to look bumpy like the rocks around it.

Cephalopods have specialized cells called chromatophores in their skin. A chromatophore consists of a sac filled with pigment and a nerve, and each chromatophore is surrounded by tiny muscles. When a cuttlefish wants to change colors, its nervous system activates the tiny muscles around the correct chromatophores. That is, some chromatophores contain yellow pigment, some contain red or brown. Because the color change is controlled by the nervous system and muscles, it happens incredibly quickly, in just milliseconds.

But that’s not all, because the cuttlefish also has other cells called iridophores and leucophores. Iridophores are layers of extremely thin cells that can reflect light of certain wavelengths, which results in iridescent patches of color on the skin. While the cuttlefish can control these reflections, it takes a little longer, several seconds or sometimes several minutes.

Like other cephalopods, the cuttlefish uses its ability to change color and pattern in order to hide from predators. It also uses these abilities to communicate with other cuttlefish, because it’s a social animal. It will also sometimes frighten potential predators away with a bright, sudden display of color changing.

The most amazing thing of all is that cuttlefish can’t see colors. They have no color receptors in their eyes. But they accurately change color to match their background, even though they can’t see the color, and they can even do so if it’s almost completely dark. While scientists have some theories as to how the cuttlefish manages this, we don’t yet know how they do it for sure. So it is still a mystery!

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, corrections, or suggestions, email us at strangeanimalspodcast@gmail.com.

Thanks for listening!

Episode 460: Blue Blobs and Graveyard Snakes

Posted on by

Podcast: Play in new window | Download (Duration: 5:58 — 6.3MB)

Subscribe: RSS | More

Further reading:

Mysterious ‘blue goo’ at the bottom of the sea stumps scientists

Three new species of ground snakes discovered under graveyards and churches in Ecuador

Show transcript:

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

I’ve come down a cold this week, and while I’m feeling better, it is settling into my chest as usual and I’m starting to cough. Since I’m still recovering and need to be in bed instead of sitting up researching animals, and since my voice is already sounding a little rough, here’s a Patreon episode this week instead of a regular episode. I had been planning to run old Patreon episodes for a few weeks in December so I could have some time off for the holidays, and those were already scheduled, so I just moved one of those episodes up to use this week instead.

This is a Patreon episode from October of 2022, where we talked about two very slightly spooky animal discoveries.

We’ll start with a suggestion from my brother Richard, about a strange newly discovered creature at the bottom of the ocean.

On August 30, 2022, the NOAA Ocean Exploration research team was off the coast of Puerto Rico. That’s in the Caribbean, part of the Atlantic Ocean. The expedition was mostly collecting data about the sea floor, including acoustic information and signs of climate change and habitat destruction. Since the Caribbean is an area of the ocean with high biodiversity but also high rates of fishing and trawling, the more we can learn about the animals and plants that live on the sea floor, the more we can do to help protect them.

When a remotely operated vehicle dives, it sends video to a team of scientists who can watch in real time and control where the rover goes. On this particular day, the rover descended to a little over 1,300 feet deep, or around 407 meters, when the sea floor came in view. Since this area is the site of an underwater ridge, the sea floor varies by a lot, and the rover swam along filming things and taking samples of the water and so forth, sometimes as deep as about 2,000 feet, or 611 meters.

The rover saw lots of interesting animals, including fish and corals of various types, even a fossilized coral reef. Then it filmed something the scientists had never seen before.

It was a little blue blob sitting on the sea floor. It wasn’t moving and it wasn’t very big. It was shaped roughly like a ball but with little points or pimples all over it and a wider base like a skirt where it met the ground. And it was definitely pale blue in color.

Then the rover saw more of the little blue blobs, quite a few of them in various places. The scientists think it may be a species of soft coral or possibly a type of sponge, possibly even a tunicate, which is also called a sea squirt. All these animals are invertebrates that don’t move, which matches what little we know about the blue blob.

The rover wasn’t able to take a sample from one of the blue blobs, so for now we don’t have anything to study except the video. But we know where the little blue blobs are, so researchers hope to visit them again soon and learn more about them.

Next, let’s return to dry land and learn about some newly discovered snakes. In fact, we’re not just on dry land, we’re way up high in the Andes Mountains in South America, specifically in some remote villages in Ecuador.

A teacher named Diego Piñán moved to the town of El Chaco in 2013, and he started noticing dead snakes on the road that he didn’t recognize. He also realized that people were killing the snakes on purpose. A lot of people are afraid of snakes, so Piñán made sure to teach his students about them so they would learn that most snakes aren’t dangerous. He also kept the dead snakes he found and preserved them in alcohol so he could figure out later what species they were. But he never could figure it out.

Then a scientist named Alejandro Arteaga assembled a team to study the animals found in remote areas of the Andes Mountains. When they came to Piñán’s town, they were excited to see the snakes he’d preserved, because even the snake experts on the team didn’t recognize the snakes either, although they were pretty certain they belonged to a genus of snakes called Atractus.

The snakes were quite pretty, gray-brown above with a bright yellow pattern underneath. They were small and slender, completely harmless to humans and pets, and they lived underground most of the time. The team searched and discovered more of the snakes living in the area. Most Atractus snakes are shy and stay away from people, but because the town of El Chaco had grown a lot recently, the snakes had moved from their home in the forest into the local cemetery. That’s right, they were burrowing around among the crypts. Of course, the snakes don’t know they’re in a graveyard. They just know they’re in a quiet place where people don’t visit very often to disturb them.

The team eventually found three new species of snake in different towns, all three described in September 2022. One species was living in the cemetery, another was in a schoolyard, and another was living near a church.

Still. Graveyard snakes.

Thanks for your support, and thanks for listening!

Episode 456: The Loch Ness Monster

Posted on by

Podcast: Play in new window | Download (Duration: 16:28 — 18.3MB)

Subscribe: RSS | More

Thanks to William who suggested we talk about the Loch Ness Monster for our big Halloween episode!

Further reading:

1888 (ca.): Alexander Macdonald’s Sightings

1933, July 22: Mr. and Mrs. George Spicer’s Loch Ness Encounter

The 1972 Loch Ness Monster Flipper Photos

White Mice, Bumblebees, and Alien Worms? Unexpected Mini-Monsterlings in Loch Ness

Further watching:

1933 King Kong clip: Brontosaurus attack!

The following stills are from the above King Kong clip:

The drawing by Rupert T. Gould for his 1934 book about the Loch Ness Monster. He drew it after interviewing Mr. Spicer about his 1933 sighting:

Show transcript:

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

This week is our big Halloween episode to finish off monster month! I hope your October has been amazing and you have fun plans for Halloween. William suggested we learn about the Loch Ness Monster, so let’s go!

We talked about the Loch Ness Monster, AKA Nessie, a really long time ago, back in episode 29. Those old episodes aren’t even available in the feed anymore—you have to go to the website to find them, and the audio isn’t very good. So here’s a revised and updated Nessie episode! There are some spooky stories associated with this one, but not too scary. Let’s call it one and a half out of five monsters on the spooky scale.

First, a little background about what Loch Ness is. It’s the biggest of a chain of long, narrow, steep-sided lakes and shallow rivers that cut the Scottish Highlands right in two along a fault line. Loch Ness is 22 miles long, or 35 km, with a maximum depth of 754 feet, or 230 meters, the biggest lake in all of the UK, not just Scotland.

During the Pleistocene, or ice age, Scotland was repeatedly covered with glaciers and ice sheets that were almost a kilometer thick. The ice only completely melted about 8,000 years ago. The massive weight of the glaciers over the fault line, where the rocks are already weaker, started the process of carving out the lake, and when the ice started melting in earnest around 10,000 years ago, the massive amounts of meltwater washed the weakened rocks out and left the deep valley that is now Loch Ness. The land slowly rose from where the ice had pressed it down, so that Loch Ness is now about 50 feet above sea level, or 15 meters. In other words, Loch Ness is only about 10,000 years old.

All the lochs and their rivers have made up a busy shipping channel since the Caledonian Canal made them more navigable with a series of locks and canals in 1822, but the area around Loch Ness was well populated and busy for centuries before that. It’s a beautiful area, so Loch Ness has also long been a popular tourist destination, well before the Nessie sightings started.

There have been stories of strange creatures in Loch Ness and all the lochs, but nothing that resembles the popular idea of Nessie. The stories were mostly of water monsters of Scottish folklore, like the kelpie we talked about in episode 351, or of out-of-place known animals like a bottle-nosed dolphin that was captured at sea and released in the loch as a prank in 1868.

The oldest monster report in the area actually comes from the 7th century, but it’s supposed to have happened in the River Ness, which drains from the lake. When local people told St. Columba about a monster that had grabbed a man swimming in the River Ness, and presumably ate him, the saint went there to take care of the monster. He told one of his followers to swim across the river, which sounds pretty rough, but the saint said, “Don’t worry, fam, I gotchu,” but in old-timey language. The man started swimming and sure enough, a water beast approached. The saint made the sign of the Christian cross and said, “Stop right there, don’t touch him. Get back, monster!” The monster swam away immediately and was never seen again.

The next sighting important enough for people to write down happened more than 1,400 years later, in 1933. The newspaper Inverness Courier printed a sighting by a woman named Aldie Mackay, who saw something that looked like a whale rolling around in the lake while she looked out the car window as her husband drove. Her husband saw it too.

Mackay’s sighting happened in mid-April of 1933 and the report appeared in May. But the big sighting that pretty much everyone has heard about happened two months later, in late July. It’s sometimes reported as an August sighting because the initial report appeared in the Inverness Courier on August 4, 1933.

A couple on holiday from London, Mr. and Mrs. George Spicer, reported seeing a large creature crossing the road around 50 meters in front of their car. In his initial report, Mr. Spicer described it as grayish with a thick body and a long neck, moving jerkily. The neck twisted and moved up and down. He didn’t see legs or a tail, but thought that a flopping movement around the downward slope of the body toward the neck might be the end of the tail, curved around the body. Mrs. Spicer disagreed and thought it was a small animal being carried at its shoulder.

Mr. Spicer initially described the monster as being about 6 to 8 feet long, or 1.8 to 2.4 meters, because, he said later, he was worried about accidentally exaggerating the size. Later, after he returned to look at the road again, he realized the monster had to have been around 25 feet long, or over 7.5 meters, since it was longer than the road was wide and its front and back ends were hidden in the trees on either side.

By the time the Spicer’s car reached the monster, it had already disappeared down the slope toward the lake, although neither witness actually saw it in the water. Mr. Spicer said that the monster actually looked like “a huge snail with a long neck.”

The Spicers didn’t stop where they saw the monster, but shortly later they stopped and talked to a man on a bicycle, telling him what they’d seen. The man must have read about the April sighting, or heard about it, because he told the Spicers that there were other recent monster reports around Loch Ness.

But something else featuring monsters happened in April of 1933. The movie King Kong was released in the first week of April, before the Spicer sighting and only a few days before the Aldie Mackay sighting. In addition to the giant gorilla King Kong, the movie featured dinosaurs, including a brontosaurus that attacks some people on a raft. Like the other monsters in King Kong, the brontosaurus was filmed using stop-motion animation, where a model is moved small increments, photographed, moved a little more, photographed again, and so on, so that when the photos are put together into a film, the model appears to move. This is how Wallace and Gromit is animated, and some old holiday specials like Rudolph the Red-Nosed Reindeer. It’s done well in King Kong, but the movements are a little jerky. To make the model look more realistic, the dinosaur was obscured by fog and trees in many scenes. It also emerges initially from the water and pursues the men onto land.

Spicer admitted in an interview a few months after his sighting that he had seen King Kong and that his monster strongly resembled the dinosaur in the movie. It’s possible that he and his wife really did see something crossing the road that they couldn’t identify, and that their memories of the King Kong dinosaurs filled in the gaps of what they couldn’t actually see. Remember that Mr. Spicer described the animal as moving jerkily with its neck moving up and down and twisting, something that also happens in the movie. He didn’t see any legs, and most of the time in the movie the brontosaurus’s legs are hidden or mostly hidden.

After the Spicer sighting, lots of previous monster sightings were reported. For instance, the Northern Chronicle newspaper printed a letter it received about an 1888 sighting, or sightings. A man named Alexander Macdonald traveled on the mail steamer pretty frequently, and he often saw what he said looked like a stubby-legged, really big salamander in the water. But by 1933 Macdonald was long dead, so no one could ask him if the letter-writer maybe just made it all up.

One good thing has come from Nessie’s popularity. Loch Ness has been studied far more than it would have been otherwise. The water is murky with low visibility, so underwater cameras aren’t much use. However, submersibles with cameras attached have been deployed many times in the loch. In 1972 a dramatic result was reported, with a clearly diamond-shaped flipper photographed from a submersible, but it turned out that the flipper was basically painted onto two photos that otherwise show nothing but the reflection of light on silt or bubbles.

Sonar scanning has been done on the entire lake repeatedly, in 1962, 1968, 1969, twice in 1970, 1981 through 1982, 1987, 2003, and 2023. They found no gigantic animals. The 1987 scan resulted in three hits of something larger than the biggest known salmon in the loch, but much smaller than a lake monster. It’s possible that the hits were only debris such as sunken boats or logs. From all the scans, though, we know there are no hidden outlets to the sea under the lake’s surface.

There are lots of known animals in and around the loch, from salmon to otters, and lots and lots of birds. Seals frequently visit, coming up the shallow River Ness through its locks. Any of these animals, especially the seals, may have contributed to Nessie sightings over the years, together with boats seen in the distance and floating debris such as logs. The lake doesn’t contain enough fish to sustain a population of large mystery animals even if they had somehow eluded all those sonar scans. No bones or dead bodies have been found, and no clear photographs have ever been taken of an unknown animal.

In the 1970s the idea that sightings of the Loch Ness Monster might actually be sightings of unusually large eels became popular. A 2018 environmental DNA study brought the idea back up, since the study discovered that there are a whole, whole lot of eels in Loch Ness. The estimate is a population of more than 8,000 eels in the loch, which is good since the European eel is actually critically endangered. But most of the eels found in Loch Ness are smaller than average, and the longest European eel ever measured was only about 4 feet long, or 1.2 meters. An eel can’t stick its head out of the water like Nessie is supposed to do, but it does sometimes swim on its side close to the water’s surface, which could result in sightings of a string of many humps undulating through the water.

There are also lots of suggested weather and water conditions in Loch Ness that could make people believe they’d seen a monster, from rare mirages to less rare standing waves. But whatever Nessie really is, there is a mystery animal in Loch Ness. It’s just not very exciting so very few people have heard of it.

A 1972 search for Nessie by the same team that announced that famous underwater photograph of a flipper, which later turned out to be mostly painted on, filmed something in the loch that wasn’t just paint. They were small, pale blobs on the grainy film. The team called them bumblebees from their shape.

Then in July of 1981, a different company searching not for Nessie but for a shipwreck from 1952, filmed some strange white creatures at the bottom of the loch. One of the searchers described them as giant white tadpoles, two or three inches long, or about 5 to 7 cm. Another searcher described them as resembling white mice but moving jerkily.

The search for the wreck lasted three weeks and the white mystery animals were spotted more than once, but not frequently. Afterwards, the company sent video of them to Dr. P Humphrey Greenwood, an ichthyologist at the Natural History Museum in London. Since this was the 1980s, of course, the film was videotape, not digital, but Dr. Greenwood got some of the frames computer enhanced. The enhancement showed that the animals seemed to have three pairs of limbs and Dr. Greenwood tentatively identified them as bottom-dwelling crustaceans, but not ones native to Loch Ness. A few years ago, zoologist Karl Shuker suggests they might be some kind of amphipod.

Amphipods are shrimp-like crustaceans that live throughout the world in both the ocean and fresh water, and most species are quite small. While they do have more than three pairs of legs—eight pairs, in fact, plus two pairs of antennae—the 1981 video wasn’t of high quality and details might easily have been lost. Some of the almost 10,000 known species of amphipod are white or pale in color and grow to the right size to be the ones filmed in Loch Ness. But no amphipods of that description have ever been caught in Loch Ness.

New amphipods are discovered all the time, of course. They’re simply everywhere, and the smallest species are only a millimeter long. But because they’re so common, it’s also easy to transport them from one body of water to another. It’s possible that the white mice crustaceans in Loch Ness traveled there on a monster hunter’s boat.

If you’re lucky enough to visit Loch Ness, definitely bring your binoculars just in case you see something big in the water. But keep your scientist hat on too, because it’s more likely that you’ll see a floating log or stump, a big fish, an anomalous wave causing an optical illusion, or some other reasonable explanation for the sighting. But you never know! Happy Halloween!

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 455: Spooky Animals

Posted on by

Podcast: Play in new window | Download (Duration: 10:55 — 12.1MB)

Subscribe: RSS | More

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!

Posted on by

Podcast: Play in new window | Download (Duration: 10:26 — 11.6MB)

Subscribe: RSS | More

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

Posted on by

Podcast: Play in new window | Download (Duration: 9:13 — 10.2MB)

Subscribe: RSS | More

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

Posted on by

Podcast: Play in new window | Download (Duration: 7:01 — 7.8MB)

Subscribe: RSS | More

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

Posted on by

Podcast: Play in new window | Download (Duration: 10:00 — 11.1MB)

Subscribe: RSS | More

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

Posted on by

Podcast: Play in new window | Download (Duration: 8:21 — 9.2MB)

Subscribe: RSS | More

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!

Posted on by

Podcast: Play in new window | Download (Duration: 10:27 — 11.7MB)

Subscribe: RSS | More

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!