Episode 463: The Big Fish Episode

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It’s an episode just absolutely full of fish! Thanks to Arthur, Yuzu, Jayson, Kabir, Nora, Siya, Joel, Elizabeth, Mac, Ryder, Alyx, Dean, and Riley for their suggestions this week!

Further reading:

Study uncovers mechanics of machete-like ‘tail-whipping’ in thresher sharks

Business end of a sawfish:

Giant freshwater stingray!

The frilled shark looks like an eel:

The frilled shark’s teeth:

The thresher shark and its whip-like tail [photo by Thomas Alexander – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=50280277]:

The Halmahera epaulette shark, looking a little bit like a long skinny koi fish [photo by Mark Erdmann, California Academy of Sciences, Attribution, https://commons.wikimedia.org/w/index.php?curid=30260864]:

A mudskipper, which is a fish even though it kind of looks like a weird frog [photo by Heinonlein – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=44502355]:

The red-lipped batfish wants a big kiss:

The male blue groper is very blue [photo by Andrew Harvey, some rights reserved (CC BY) – https://www.inaturalist.org/photos/62196538, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=157789928]:

The giant oarfish is very long:

Show transcript:

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

This week we have a big fish episode! I mean, it’s a big episode about a lot of different fish, not necessarily fish that are big—although some of them sure are! Thanks to Arthur, Yuzu, Jayson, Kabir, Nora, Siya, Joel, Elizabeth, Mac, Ryder, Alyx, Dean, and Riley. I told you this is a big fish episode.

Let’s jump right in with a fish suggested by Jayson, the sawfish. There are five species of sawfish alive today. The smallest can still grow over 10 feet long, or 3 meters, while the biggest species can grow over 20 feet long, or 6 meters. The largest sawfish ever reliably measured was 24 feet long, or 7.3 meters.

The sawfish lives mostly in warm, shallow ocean waters, usually where the bottom is muddy or sandy. It can also tolerate brackish and even freshwater, and will sometimes swim into rivers and live there just fine.

The sawfish is a type of ray, and rays are most closely related to sharks. Like sharks, rays have an internal skeleton made of cartilage instead of bone, but they also have bony teeth. You can definitely see the similarity between sharks and sawfish in the body shape, although the sawfish is flattened underneath, which allows it to lie on the ocean floor. There’s also another detail that helps you tell a sawfish from most sharks: the rostrum, or snout. It’s surprisingly long and studded with teeth on both sides, which makes it look like a saw.

The teeth on the sawfish’s saw are actual teeth. They’re called rostral teeth and the rostrum itself is part of the skull, not a beak or a mouth. It’s covered in skin just like the rest of the body. The sawfish’s mouth is located underneath the body quite a bit back from the rostrum’s base, and the mouth contains a lot of ordinary teeth that aren’t very sharp.

Since the sawfish has plenty of teeth in its mouth, you may be wondering how and why it also has extra teeth on both sides of its saw. It’s because the rostral teeth evolved from dermal denticles.

Dermal denticles look like scales but they’re literally teeth, they’re just not used for eating. Sharks have them too, along with some other fish. In the case of the sawfish, the rostral teeth grow much larger than an ordinary dermal denticle, and stick out sideways.

Both the rostrum and the head are packed with electroreceptors that allow the sawfish to sense tiny electrical charges that animals emit as they move. This might mean a school of fish swimming through muddy water, or it might mean a crustacean hiding in the sand. The sawfish sometimes uses its rostrum to dig prey out of the sand, but it also uses it to slash at fish or other animals. Then the sawfish can either grab the injured or dead animal with its mouth or pin it to the sea floor with its rostrum to maneuver it into its mouth. Its mouth is relatively small and it prefers to swallow its food whole, head-first, so it can only eat fish that are smaller than its mouth. That’s also why it doesn’t want to eat people. Its mouth is too small.

Yuzu wanted to learn about another shark relation, the giant freshwater stingray, which lives in rivers in southeast Asia. It’s dark gray-brown on its back and white underneath, and it has a little pointy nose at the front of its disc. It also has dermal denticles on its back.

The giant freshwater stingray has a rounded, flattened body, and it’s really big. A big female can grow over 7 feet across, or 2.2 meters. Its tail is long and thin with the largest spine of any stingray known, up to 15 inches long, or 38 cm. Its tail is so long that if you measure the giant freshwater stingray by length including its tail, instead of by width of its disc, it can be as much as 16 feet long, or about 5 meters. Some researchers think there might be individuals out there much larger than any ever measured, possibly up to 16 feet wide. The length and thinness of the tail gives the ray its other common name, the giant freshwater whipray, because its tail looks like a whip.

While we’re talking about shark relations, let’s go ahead and talk about a few actual sharks. Kabir wanted to learn about the frilled shark, which looks and acts more like an eel than a shark. A big female can grow up to 6 and a half feet long, or 2 meters. Males are a little shorter on average. The frilled shark has the same anatomy found in ancient sharks from the fossil record, dating back at least 95 million years. It’s found a body type that works for it.

The frilled shark lives on the continental shelf in many parts of the world, and while it technically lives near the sea floor, at night it migrates closer to the ocean surface to find fish, squid and other cephalopods, and other food. There are two species known, with the southern African frilled shark only discovered in 2009.

The frilled shark is dark brown or gray, and its jaws are long and contain clusters of teeth in little rows. Each tooth has three sharp points, and there are 300 teeth, so a frilled shark has 900 points in its mouth. The points are so sharp that scientists examining dead sharks have gotten cut on the teeth, which would be really embarrassing if you’re a shark expert that was bitten by a dead shark. The frilled shark can open its jaws extremely wide to swallow fish and other animals that are up to about half the size of the shark itself. It even eats other sharks.

Next, Joel wanted to learn about the thresher shark. It’s a truly big fish that can grow up to 20 feet long, or over 6 meters. It’s a fast, slender shark with a tail fin that can be as long as its body. It eats a lot of other animals, including birds and crustaceans, but it specializes in hunting fish that travel in schools, like tuna, sardines, and mackerel. It uses its incredibly long tail as a whip, slapping a fish to stun it so the shark can eat it. When it whips its tail, its body flexes so that its head points downward in the water with the tail snapping forward over it. A 2024 study determined that the thresher shark’s vertebral column is fortified to allow it to work like a catapult. The thresher shark can also use its long tail to help it leap out of the water completely, although scientists don’t know why it wants to do that.

There are three species of thresher shark known to science, but in 1995 a genetic analysis revealed the possible presence of a fourth species. Scientists think it lives in the eastern Pacific and may look similar to the bigeye thresher, enough that it gets misidentified as that species when it’s seen. The three known species of thresher shark are hard to tell apart at a distance as it is.

And for our last shark, Siya asked about the Halmahera epaulette shark. It’s light brown with darker and lighter spots, and is a slender shark that can grow a little over 2 feet long, or 68 cm. It lives around Indonesia, and it might live in other places too. We don’t know yet, because it was only discovered in 2013 and only two specimens have ever been found.

Epaulette sharks are also called walking sharks, because they use their fins to walk along the sea floor and explore crevices in rocks. Some species can even walk short distances on land to enter tidal pools and other places where they can find food. They live in warm, shallow water, usually near reefs or islands, and they eat whatever small animals they can find. There are nine species known, but there are undoubtedly more than haven’t yet been discovered by science. You might think this is strange for a shark that can walk on land, but walking sharks are nocturnal and not very big, so it’s easy to miss them when they’re out and about.

That brings us to Arthur’s suggestion, the mudskipper. The mudskipper also uses its fins to walk. Its pectoral fins are muscular and allow it to climb out of the water and onto land, climb into low branches, and even jump. Its pectoral fins look like little arms, complete with an elbow. The elbow is actually a joint between the actual fins and the radial bones, which in most fish are hidden within the body but which stick out of the mudskipper’s sides a short distance. This helps it move around on land more easily. Its pelvic fins are also shaped in such a way that they act as little suction cups on land.

The mudskipper is so good at living on land that it’s actually considered semi-aquatic. It lives in mudflats, mangrove swamps, the mouths of rivers where they empty into the ocean, and along the coast, although it prefers water that’s less salty than the ocean but more salty than ordinary freshwater. It only lives in tropical and subtropical areas because it needs high humidity to absorb oxygen through its skin and the lining of its mouth and throat.

The mudskipper is a fish, but it looks an awful lot like a frog in some ways, due to convergent evolution. It has a wide mouth and froglike eyes at the top of its head and will often float just under the water with its eyes above water, looking for insects it can catch. The largest species grows about a foot long, or 30 cm, and while it has some scales, its body is coated with a layer of mucus to help it retain moisture. It spends most of the day on land, hunting for insects and other small animals. Not only can it absorb oxygen through its skin, it keeps water in its gill chambers to keep the gills wet too. It even has a little dimple under its eye that holds water, that helps keep its eyes moist.

The mudskipper also takes a big mouthful of water with it when it climbs on land, but not to breathe. It uses the water to hunt with. When it encounters an insect or other small animal on land, it carefully rotates its mouth–yes, it can rotate its mouth, which has led to me trying to rotate my mouth, something humans can’t actually do–so that its mouth is just above the animal. Then it spits out the mouthful of water onto the insect and immediately sucks the water back into its mouth, carrying the insect with it. When it catches an animal underwater, it opens its big mouth quickly, causing suction that sucks the animal right into its mouth. It also has sharp teeth, so when an animal is in its mouth, it’s not getting out again.

Alyx, Dean, and Riley suggested we talk about the red-lipped batfish, a type of anglerfish only found around the Galapagos Islands in the Pacific Ocean. It lives on the ocean floor where the water is fairly shallow, and it grows about 8 inches long, or 20 cm. It’s usually a mottled brown, green, or grey with a white stomach, but its mouth is bright red. It looks like it’s wearing lipstick. It eats fish and other small animals, which it attracts using a lure on its head, a highly modified dorsal fin called an illicium.

The weirdest thing about the red-lipped batfish is actually its fins. It prefers to walk on the bottom of the ocean instead of swim, and it has modified pectoral fins called pseudolegs. The pseudolegs make it look a little bit like a weird frog with lipstick. Researchers think the red lips may be a way to attract potential mates, presumably ones who are hoping for a big smooch. At this rate I’m wondering if there are any fish that don’t walk on their fins.

Next, Mac wanted to learn about a fish called the payara. The problem is, there are two fish with that name, so let’s learn about them both!

The first payara is a pretty, silvery fish with a couple of small dark spots on its body. It’s found in the Amazon basin in South America and can grow at least 1 foot 8 inches long, or 51 cm. It’s sometimes kept in large aquariums, and is sometimes called the vampire tetra or the vampire fish because it has a pair of long fangs that it uses to stab other fish with before eating them. Its fangs stick up from its lower jaw, though, so if it’s a vampire fish, it’s an upside-down vampire.

As for the other payara, it’s related to the first kind and is also found in South America, but it’s even larger. It can grow a little over 3 feet long, or 3.3 meters. Its teeth are also large and sharp, including two big fangs sticking up from its lower jaw. In a big individual, its fangs may be 4 inches long, or 10 cm. This is not a fish you want to get bitten by! You are probably not in any danger of being bitten by this payara, though, unless you happen to spend a lot of your time swimming along the bottom of rivers in the Amazon.

Quite a while ago, Ryder suggested we learn about the pipe cichlid. I tried to find more about it and I think it’s actually a fish called the pike cichlid. Pike cichlids are popular freshwater aquarium fish that are native to tropical and subtropical parts of eastern South America, and there are about 45 species known so far. They’re typically quite small, with most species only growing a few inches long, or around 8 cm, although some species are more than twice that length. The pike part of their name comes from their shape, like a teeny-tiny pike, a predatory fish that can grow up to 5 feet long, or 1.5 meters. Pike and pike cichlids aren’t related, but pike cichlids are predatory. It’s just that instead of eating other fish, ducks, frogs, and even reptiles and mammals that end up in the water, the pike cichlid mostly eats insects.

Elizabeth wanted to learn about the blue groper, a fish found around Australia and nowhere else in the world. It lives around reefs and rocky areas near the coast, where it can find plenty of starfish, urchins, crustaceans, and other small animals to eat. It can grow almost six feet long, or 1.75 meters, and its teeth are peg-shaped to help it pick mollusks and other animals off of rocks before crushing them.

It’s called the blue groper because males are a beautiful blue color, while females are brown or reddish-brown and young fish are green. All young blue gropers are female, and as they grow up some change to become males while most remain females. The fish grow very slowly and can live to be at least 70 years old, so the fish don’t even reach maturity until they’re 15 or 20 years old. When a fish is around 30 or 35 years old, it will change gender again, this time becoming a male. But if the male of a group dies, the group’s dominant female will change into a male and turn blue. This is common in the family of fish that the blue groper belongs to, Labridae, also called wrasses.

Let’s finish with a suggestion from Nora, the oarfish. The giant oarfish and Russell’s oarfish can both grow at least 26 feet long, or 8 meters, and possibly much longer. Most of its length is tail, which often shows damage from being bitten. Since its organs are all close to the front of its body, and it doesn’t need its tail for swimming, if a predator takes a bite out of its tail, the fish is going to be fine. The oarfish can even detach pieces of its tail if it needs to, the same way some lizards can, to distract a potential predator. Like those lizards, the tail doesn’t grow back.

The oarfish is silvery in color with a red crest on its head and a mane-like fin down its back, although it’s actually an elongated dorsal fin. It has extremely long pelvic fins too.

The giant oarfish has a short, blunt snout and no teeth because it filters krill and other tiny animals from the water. It doesn’t have scales. Instead, its skin is soft with a delicate layer called ganoine that gives it a shimmery, almost metallic appearance. The long filaments of the crest on its head and its pelvic fins are also delicate. But although it’s long and slender like an eel, it actually swims vertically with its head pointing up and its tail down. We’re not sure why, although one theory is that this minimizes its profile to predators looking up from below. It can swim quickly straight up and down to avoid predators that mostly just swim forward.

We know so little about the oarfish, and what we know is so strange, that it’s the next best thing to a sea serpent. The first living giant oarfish was only filmed in 2001. Most oarfish are only seen when they’re dead or dying. It seems to live throughout the world’s oceans, except for the Arctic and Antarctic, and is a deep-sea fish but may migrate closer to the surface at night to find more food.

A Japanese legend says the oarfish predicts earthquakes. If an oarfish is seen near the surface or washes up on a beach, an earthquake is supposed to be imminent. That seems to be a coincidence, though.

The oarfish looks like a sea serpent, and some people think it might have given rise to some sea serpent sightings. This may or may not be the case, but it’s certainly a mysterious fish.

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 462: Cryptic Coloration

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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 461: Therizinosaurus and Its CLAWS

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Further reading:

Study: Giant Therizinosaurs Used Their Meter-Long, Sickle-Like Claws for Display

Show transcript:

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

I am delighted to report that Therizinosaurus lived in what is now Mongolia in Central Asia, in the Gobi Desert. 70 million years ago, the land wasn’t a desert at all but a forest with multiple rivers and streams flowing through it. Lots of other dinosaurs and birds lived in the area, including a tyrannosaurid called Tarbosaurus that was probably the only predator big enough to kill Therizinosaurus.

When the first Therizinosaurus fossils were discovered in the 1950s, they were initially thought to belong to a type of giant turtle. Later it was reclassified as a sauropod relation, not a turtle. These days, we know for sure it’s not a turtle and we’re pretty sure it’s not anything like a sauropod.

The Therizinosaurus fossils found so far are incomplete. All we have are some ribs, one hind foot, and mostly complete arms and hands. We don’t have any parts of the skull or any vertebrae, so paleontologists still have a lot of questions about what Therizinosaurus looked like and how it lived, although we have more complete specimens of some of its close relations to help scientists make good guesses. Luckily we have its hands, because its claws are enormous. Therizinosaurus had claws bigger than any other dinosaur known.

Therizinosaurus was a big dinosaur overall, with an estimated length of 33 feet, or 10 meters, although until a more complete specimen is discovered we can’t know for sure how big it really was. It may have stood up to 16 feet tall, or 5 meters, and walked on its hind legs. It’s classified as a theropod these days, a group that includes famous dinosaurs like T. rex and Spinosaurus, but it wasn’t closely related to those big fast meat-eaters. Most paleontologists think Therizinosaurus ate plants, but again, we don’t know for sure since we don’t have any of its teeth to examine. Its closest relatives were herbivorous but its immediate ancestors were carnivorous.

If Therizinosaurus was a plant-eater, why did it have such enormous claws? Its claws were seriously terrifying! Its arms were big and strong in general, measuring about 8 feet long, or 2.5 meters, including long, slender fingers, and the claws measured over three feet long! That’s more than a meter long. If the claws were covered with a keratin sheath, which is probable, they would have been even longer when Therizinosaurus was alive. They were relatively thin and straight with a curve at the end.

There are many reasons why an animal develops big claws. Predators need claws to help grab prey or tear meat into pieces, or an animal may need big claws to help it dig or climb trees. Claws are also great for defense. Some animals use claws to grab tree branches and bend them closer to the animal’s mouth, which is something that giant ground sloths probably did, at least sometimes.

The new study published in February 2023 examined the claws of Therizinosaurus and lots of other dinosaurs to learn how strong they were. The claws were 3D scanned, and then the scans were used in various models that measured the stress placed on each claw in various different activities.

The study discovered that the claws of different dinosaurs were strong in different ways depending on what they were used for, which wasn’t a surprise. What was a surprise was that Therizinosaurus’s claws were weak no matter which model the scientists used.

In other words, Therizinosaurus probably didn’t use its claws to fight other dinosaurs unless it just had to, because they would break too easily. It wouldn’t have dug with its claws or even used them to hook branches down closer to its mouth. As far as we can tell, its claws were basically useless.

But obviously, Therizinosaurus used its claws for something or it wouldn’t have evolved to have such gigantic claws. The study concluded that the giant claws must have been for display, to attract a mate or maybe just scare off potential predators.

Lots of animals have special features used to attract a mate, like a peacock’s tail. Sometimes these features serve a double purpose, like a male deer’s antlers. The size of the antlers show how healthy he is, and he also uses them to fight other males. I’m not a claw expert, but as far as I know there aren’t any other animals known that use their claws for display only.

It’s possible that Therizinosaurus did use its claws for something else, we just don’t know what. It’s also possible that the study had flaws that a follow-up study will discover, and Therizinosaurus’s claws weren’t actually so weak. But for now, as far as we know, during mating season Therizinosaurus would strut around waving its super-long claws to show how amazing it was. And, let’s face it, Therizinosaurus really was amazing.

Thanks for your support, and thanks for listening!

Episode 460: Blue Blobs and Graveyard Snakes

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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 458: The Tasmanian Tiger and Friends

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Thanks to Viki, Erin, Weller, and Stella for their suggestions this week!

Further reading:

Tasmanian tiger pups found to be extraordinary similar to wolf pups

The thylacine could open its jaws really wide:

A sugar glider, gliding [photo from this page]:

A happy quokka and a happy person:

A swimming platypus:

Show transcript:

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

This week we’re going to learn about some marsupial mammals suggested by Erin, Weller, and Stella, and a bonus non-marsupial from Australia suggested by Viki.

Marsupials are mammals that give birth to babies that aren’t fully formed yet, and the babies then finish developing in the mother’s pouch. Not all female marsupials actually have a pouch, although most do. Marsupials are extremely common in Australia, but they’re also found in other places around the world.

Let’s start with Weller’s suggestion, the Tasmanian tiger. We’ve talked about it before, but not recently. We talked about it in our very first episode, in fact! Despite its name, it isn’t related to the tiger at all. Tigers are placental mammals, and the Tasmanian tiger is a marsupial. It’s also called the thylacine to make things less confusing.

The thylacine was declared extinct after the last known individual died in captivity in 1936, but sightings have continued ever since. It’s not likely that a population is still around these days, but the thylacine is such a great animal that people hold out hope that it has survived and will one day be rediscovered.

It got the name Tasmanian tiger because when European colonizers arrived in Tasmania, they saw a striped animal the size of a big dog, about two feet high at the shoulder, or 61 cm, and over six feet long if you included the long tail, or 1.8 meters. It was yellowish-brown with black stripes on the back half of its body and down its tail, with a doglike head and rounded ears.

The thylacine was a nocturnal marsupial native to mainland Australia and the Australian island of Tasmania, but around 4,000 years ago, climate change caused more and longer droughts in eastern Australia and the thylacine population there went extinct. By 3,000 years ago, all the mainland thylacines had gone extinct, leaving just the Tasmanian population. The Tasmanian thylacines underwent a population crash around the same time that the mainland Australia populations went extinct—but the Tasmanian population had recovered and was actually increasing when Europeans showed up and started shooting them.

The thylacine mostly ate small animals like ducks, water rats, and bandicoots. Its skull was very similar in shape to the wolf, which it wasn’t related to at all, but its muzzle was longer and its jaws were comparatively much weaker. Its jaws could open incredibly wide, which usually indicates an animal that attacks prey much larger than it is, but studies of the thylacine’s jaws and teeth show that they weren’t strong enough for the stresses of attacking large animals.

Next, Stella wanted to learn about the sugar glider, and I was surprised that we haven’t talked about it before. It’s a nocturnal marsupial native to the forests of New Guinea and parts of Australia, with various subspecies kept as exotic pets in some parts of the world. It’s called a glider because of the animal’s ability to glide. It has a flap of skin between its front and back legs, called a patagium, and when it stretches its legs out, the patagia tighten and act as a parachute. This is similar to other gliding animals, like the flying squirrel.

The sugar glider resembles a rodent, but it isn’t. It’s actually a type of possum. It lives in trees and has a partially prehensile tail that helps it climb around more easily, and of course it can glide from tree to tree. It’s an omnivore that eats insects, spiders, and other small animals, along with plant material, mainly sap. It will gnaw little holes in a tree to get at the sap or gum that oozes out. It will also eat fruit, nectar, pollen, and seeds, but most of the time it prefers to hang around flowers and wait for insects to approach. Then it grabs and eats the insect without having to chase it.

The sugar glider is gray with black and white markings, big eyes that allow it to see well in darkness, rounded ears, and a really long, thick, furry tail. It’s a social animal that lives in family groups in small territories. Both males and females help take care of the joeys when they’re out of the mother’s pouch, mainly by helping them stay warm when it’s cold.

Our last marsupial of this episode is Erin’s suggestion, the quokka. It’s about the size of a domestic cat, related to wallabies and kangaroos. It’s shaped roughly like a chonky little wallaby but with a smaller tail and with rounded ears, and it’s grey-brown in color.

The quokka is considered incredibly cute because of the way its muzzle and mouth are shaped, which makes it look like it’s smiling. If you take a picture of a quokka’s face, it looks like it has a happy smile and that, of course, makes the people who look at it happy too.

This has caused some problems, unfortunately. People who want to take selfies with a quokka sometimes forget that they’re wild animals. While quokkas aren’t very aggressive and are curious animals who aren’t usually afraid of people, they can and will bite when frightened. Touching a quokka or giving it food or drink is strictly prohibited, since it’s a protected animal.

The quokka is most active at night. It sleeps during most of the day, usually hidden in a type of prickly plant that helps keep predators from bothering it. It gets most of its water needs from the plants it eats, and while it mostly hops around like a teensy kangaroo, it can also climb trees.

Let’s finish with our non-marsupial animal. Viki wanted to learn about the platypus, which we haven’t really talked about since way back in episode 45. It’s native to Australia and is very weird-looking, so it’s easy to think it’s another marsupial, but the platypus is even weirder than that. It’s not a marsupial and it’s not a placental mammal. Instead, it’s an extremely rare third type of mammal called a monotreme.

There are only two kinds of monotremes alive today, the echidna and the platypus. Monotremes retain a lot of traits that are considered primitive in mammals. Instead of giving birth to live babies, a monotreme mother lays eggs. The eggs have soft, leathery shells, but when they hatch, the babies look like marsupial newborns.

The platypus is sometimes called the duck-billed platypus, because its snout does kind of look like a duck’s bill, but instead of being hard, the snout is soft and rubbery, and it’s packed with electroreceptors that allow the platypus to sense the tiny electrical fields generated by muscle contractions in its prey. I bet that was not what you expected from what looks like a small beaver with a duck bill!

The platypus grows not quite two feet long, or 50 cm, and has short, dense, brown fur. It spends a lot of its time in the water, and has a flattened tail that acts as a rudder when it swims, along with its hind feet. It propels itself through the water with its front feet, which are large and have webbed toes. It lives in eastern Australia along rivers and streams, and digs a short burrow in the riverbank to sleep in. The female digs a deeper burrow before she lays her eggs, and she makes them a nest out of leaves.

Baby platypuses are called puggles, and while the mother doesn’t have a pouch, she keeps her babies warm by tucking them against her tummy with her tail. Monotremes don’t have teats, but they do produce milk from what are called milk patches. The puggles lick the milk up. Until scientists figured out that monotremes have these milk patches, in 1824, they thought monotremes weren’t mammals at all but something more closely related to reptiles.

Monotremes were much more common throughout the world until about 60 to 70 million years ago, when marsupials started outcompeting them. Marsupials don’t spend much time in water, though, because if they did their joeys would drown. The platypus and echidna both survived to the present day because they’re adapted for the water. The platypus mainly navigates in the water using its electrolocation abilities, and eats worms, fish, insects, crustaceans, and anything else it can catch.

It’s easy to think, “Oh, that mammal is so primitive, it must not have evolved much since the common ancestor of mammals, birds, and reptiles was alive 315 million years ago,” but of course that’s not the case. It’s just that the monotremes that survived did just fine with the basic structures they evolved a long time ago, and they’re still going strong today.

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 457: Parrots!

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Thanks to Fleur, Yuzu, and Richard from NC for their suggestions this week!

Further reading:

World’s rarest parrot, extinct in wild, hatches at zoo

Kakapo recovery

This Parrot Stood 3 Feet Tall and Ruled the Roost in New Zealand Forests 19 Million Years Ago

The magnificent palm cockatoo:

The gigantic kakapo:

Show transcript:

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

This week we have a bird episode, specifically some interesting parrots. Thanks to Fleur, Yuzu, and Richard from NC for their suggestions!

Parrots are intelligent, social birds that are mostly found in tropical and subtropical parts of the world, but not always. Most parrots eat plant material exclusively, especially seeds, nuts, and fruit, but some species will eat insects and other small animals when they get the chance. Most parrots are brightly colored, but again, not always. And, unfortunately, most parrot species are endangered to some degree due to habitat loss, hunting for their feathers and for the pet trade, and introduced predators like cats and rats.

All parrots have a curved beak that the bird uses to open nuts and seeds, but which also acts as a tool or even a third foot when it’s climbing around in trees. All parrots have strong clawed feet that they also use to climb around and perch in trees, and to handle food and tools.

Let’s start with Yuzu’s suggestions, the cockatoo and the parakeet. A parakeet is a small parrot, but it’s a term that refers to a lot of various types of small parrots. This includes an extinct bird called the Carolina parakeet.

It was small parrot that was common throughout a big part of the United States. It had a yellow and orange head and a green body with some yellow markings, and was about the size of a mourning dove or a passenger pigeon. Its story of extinction mirrors that of the passenger pigeon in many ways. The Carolina parakeet lived in forests and swamps in big, noisy flocks and ate fruit and seeds, but when European settlers moved in, turning forests into farmland and shooting birds that were considered pests, its numbers started to decline. In addition, the bird was frequently captured for sale in the pet trade and hunted for its feathers, which were used to decorate hats.

By 1860 the Carolina parakeet was rare anywhere except the swamps of central Florida, and by 1904 it was extinct in the wild. The last captive bird died in the Cincinnati Zoo in 1918, which was not only the same zoo where the last passenger pigeon died in 1914, it was the same cage. It was declared extinct in 1939.

The parakeet Yuzu is probably referencing is the budgie, or budgerigar. It’s the one that’s extremely common as a pet, and it’s native to Australia. In the wild it’s green and yellow with black markings, but the domestic version, which has been bred in captivity since the 1850s, can be all sorts of colors and patterns, including various shades of blue, yellow all over, white, and piebald, meaning the bird has patches of white on its body.

The budgie can learn to repeat words and various sounds, especially if it’s a young bird. I had two parakeets as a kid, named Dandelion and Sky so you can guess their colors, and neither learned to talk although I really tried to teach them. Some birds just aren’t interested in mimicry, while others won’t stop, especially if they get attention when they speak.

In the wild, budgies live in flocks that will travel long distances to find food and water. The birds mostly eat grass seeds, especially spinifex, but will sometimes eat wheat, especially in areas where farmland has destroyed much of their wild food. They’re social birds that are sometimes called lovebirds, although that’s the name of a different type of bird too, because they will preen and feed their mates.

Like many birds, the parakeet can see ultraviolet light, and their feathers glow in UV light. This makes them even more attractive to potential mates, as if the parakeet wasn’t beautiful enough to start with.

Yuzu also asked about the cockatoo. There are 21 species of cockatoo, also native to Australia and other nearby places, including Indonesia and New Guinea. It’s much larger than the budgie and most species have a crest of some kind. It lives in flocks and eats various types of plant material, including flowers and roots, but it will also eat insects. The cockatoo isn’t as brightly colored as many parrots, and is usually black, white, or gray, often with patches of color on the crest, cheeks, or tail.

The pink cockatoo is white with pale salmon pink markings on the body, and brighter pink and yellow on its crest. The sulphur-crested cockatoo is white with pale yellow on the undersides of the wings and tail, and a bright yellow crest. We talked about the palm cockatoo in episode 23 because not only does it look like it should be a drummer of the Muppet Animal variety, since it’s black with red cheeks and a big messy crest, it does actually use sticks and nuts to drum against tree branches, to attract a mate.

Richard from NC suggested we learn about Spix’s macaw, also called the blue macaw, because it’s considered one of the world’s rarest parrots. In fact, it was declared extinct in the wild in 2019. It only survives at all because of intensive conservation efforts, including a captive breeding program spread over multiple zoos.

The blue macaw is native to one small part of Brazil in South America, although it used to be much more common several hundred years ago. It’s blue with a gray-blue head. It’s such a beautiful parrot that it was driven to extinction by people trapping the birds to sell as pets, even though that had been outlawed by Brazil, although its numbers had been falling for centuries due to habitat loss. It relied on a particular species of tree called the tree of gold, because its flowers are bright yellow. The blue macaw nested in these trees, and its seedpods were one of its main foods. As groves made up of the tree of gold were chopped down to make way for farmland and towns, the bird became more and more rare.

Luckily, even though the blue macaw doesn’t breed very quickly in captivity, by 2022 there were enough healthy young birds to release twenty into the wild. Just a few weeks ago as this episode goes live, another egg has hatched in captivity in a bird conservation center in Belgium, after the previous hundred eggs were infertile and never hatched.

Next, Fleur wanted to learn more about the kakapo, a flightless, nocturnal parrot that lives only in New Zealand. We talked about it in episode 313, but it’s definitely time to revisit it.

The kakapo is the largest living parrot. It has green feathers with speckled markings, blue-gray feet, and discs of feathers around its eyes that make its face look a little like an owl’s face. That’s why it’s sometimes called the owl parrot. Males are almost twice the size of females on average. It can grow over two feet long, or 64 cm, and can weigh as much as 9 lbs, or about 4 kg. That’s way too heavy for it to fly, but its legs are short but strong and it will jog for long distances to find food. It can also climb really well, right up into the very tops of trees. It uses its strong legs and its large curved bill to climb. Then, to get down from the treetop more efficiently, the kakapo will spread its wings and parachute down, although its wings aren’t big enough or strong enough for it to actually fly. A big heavy male sort of falls in a controlled plummet while a small female will land more gracefully.

The kakapo evolved on New Zealand where it had almost no predators. A few types of eagle hunted it during the day, which is why it evolved to be mostly nocturnal. Its only real predator at night was one type of owl. As a result, the kakapo was one of the most common birds throughout New Zealand when humans arrived.

But by the end of the 19th century, the kakapo was becoming increasingly rare everywhere. By 1970, scientists worried that the kakapo was already extinct. Fortunately, a few of the birds survived in remote areas. Several islands were chosen as refuges, and all the kakapos scientists could find were relocated to the islands, 65 birds in total. While the kakapo is doing a lot better now than it has in decades, it’s still critically endangered. The current population is 237 individuals according to New Zealand’s Department of Conservation.

The kakapo may be the largest living parrot, but it’s not the largest parrot that ever lived. That would be the giant parrot. It’s known only from a few fossils dated to between 16 and 19 million years ago, but from those fossils scientists estimate that the giant parrot grew around 3 feet tall, or almost a meter, and possibly weighed almost twice what the kakapo weighs. It’s the largest parrot that ever lived as far as we know, and it was probably related to the kakapo.

We don’t know a lot about the giant parrot because only two fossils have been found, both of them leg bones and probably from the same individual. They bones are so big that scientists initially thought they belonged to an eagle. Hopefully soon more fossils will come to light so we can learn more about the giant parrot. For all we know, those leg bones belonged to a young parrot that wasn’t fully grown yet. Maybe the adults were even bigger than we think!

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 456: The Loch Ness Monster

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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

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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 454: Bats!

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This week we’re going to learn about a bunch of bats! Thanks to John, Murilo, and Alexandra for their suggestions!

Further reading:

Why Bats Can’t Walk: The Evolutionary Lock That Keeps Them Flying

On a Wing and a Song—Bats Belt out High-Pitched Tunes to Woo Mates

Why some bats hunt during the day

Puzzling Proto-Bats

A pekapeka just walking around catching bugs on the ground [photo by Rod Morris, from link above]:

BLOOOOOOD! but a really cute smile too:

The western red bat looks ready for Halloween!

Show transcript:

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

This week as monster month continues, we’re going to learn about bats! We’ve talked about bats in lots of previous episodes, but we have a lot of really neat information in this one that we’ve never covered before. Thanks to John, Alexandra, and Murilo for their suggestions!

John suggested we learn about diurnal bats and also asked if there are any flightless bats, maybe ones that live on islands. There are lots of island-living bats, and many birds that live on islands evolve to be flightless. It makes sense that bats might do the same thing–but I couldn’t find any information about any known bat that has lost the ability to fly.

The reason seems to be how highly derived bats are. That means they’re specialized, the only mammal known that has ever evolved true flight. Unlike birds, which don’t need to use their legs when flying, bats’ legs are actually part of the wings. The wing membranes, called patagia, stretch not just between the elongated finger bones of the bat’s hands, they also stretch between the arms and legs, and connect the legs too.

A January 2025 study comparing bat skeletons to the skeletons of birds determined that unlike in birds, where the size of the legs doesn’t have anything to do with the size of the wings, in bats the leg size and the wing size are closely related. If a bat evolves smaller wings, its legs also evolve to become smaller. That’s why there are no bats that resemble ostriches, with tiny wings but really long legs.

Another possible reason is that bat legs have evolved to point backwards compared to other animals. It’s not just the feet, the knees are also rotated backwards. That’s why bats hang upside-down when they’re not flying. Many species of bat never land on the ground, because they literally can’t walk at all.

But there are a few species of bats that can walk quite well. One is the increasingly threatened New Zealand lesser short-tailed bat. It lives in a few places in both the North and South Islands, as well as some small islands off the coast, although it used to be much more widespread. It’s also called by its Maori name, the pekapeka.

The pekapeka mainly lives in forested areas and is quite small. It’s brown with a lighter belly, and it has big ears, as do most bats. Its eyes are small and its vision isn’t very good, but it has a good sense of smell. Its wings are small so its legs are correspondingly small too, but its legs are also strong despite their size. It has a clawed thumb toe on its feet and on its wings that helps it climb around in trees when it needs to, and it also spends about half of its time on the ground. It walks just fine, crawling with its wings folded so that the ends point up and back, out of the way. And yes, its legs are rotated backwards as you’d expect in a bat, and it roosts by hanging from its feet in trees.

The pekapeka flies normally and catches insects using echolocation, just like other microbats throughout the world. It especially likes moths. Unlike almost all other bats, it finds a lot of its food on the ground too, using its sense of smell to track down spiders, insects and larvae, and other small invertebrates. It will actually dig into the dirt and leaf litter to find food. It also eats nectar and flowers, and is an important pollinator of some plants.

One great thing about the pekapeka is that the males sing to attract a mate. The sound is so high-pitched that it’s not practical to share it here, because you probably wouldn’t be able to hear it, but I’ll link to an article that has a sample bat song so you can listen.

Another bat that can walk just fine is one suggested by Murilo, the vampire bat. In movies, vampire bats are usually depicted as being humongous, as big as a person! In reality, those big bats are actually megabats, and megabats mostly eat fruit. Megabats are the ones that are sometimes called sky puppies, because they don’t rely very much on echolocation so they don’t have the complicated ears and noses that microbats do. Until recently scientists thought megabats couldn’t echolocate at all, but now we know they can, they’re just not all that good at it. The vampire bat is tiny in comparison.

There are three species of vampire bat alive today. They share the same subfamily, Desmodontinae, but have been classified in different genera because they differ considerably from each other. Their other relations are ordinary bats that eat insects, fruit, and other things that you’d expect from bats. Vampire bats really do eat blood exclusively.

The hairy-legged vampire bat is the most basal of the three species, meaning it retains traits that haven’t changed as much from its ancestors. It feeds exclusively on bird blood. The white-winged vampire bat also mostly feeds on bird blood, but it will sometimes eat the blood of mammals. It’s the common vampire bat that eats the blood of mammals.

Vampire bats probably evolved from ancestors that ate insects. Scientists hypothesize that they might have originally specialized in eating ectoparasites of other animals, or possibly insects that were attracted to animal wounds. If that’s the case, the bat would have already been eating a lot of blood along with the insects, and at some point it started taking a shortcut to getting that yummy blood. We know this has happened at least one other time, in a bird.

I thought we had talked about the red-billed oxpecker in an old episode, but if we did, I couldn’t find it. It lives throughout the savannas of sub-Saharan Africa and is brown with a bright orange bill and eyes, with a yellow eye ring. It eats ticks that it picks off rhinoceroses, cattle, and other large mammals, but it actually mainly eats blood. It’s happy to eat the ticks, because they’re full of blood, and the animals it perches on are happy that it eats ticks, but the bird will also peck at wounds so it can drink blood directly from the animal.

So it’s likely that the vampire bat started out eating ticks or other ectoparasites, then began eating the blood that oozed from the wound after it removed a tick. From there it was a short step to biting the animal to cause blood to flow, and within four million years, it was fully adapted to drinking blood.

The vampire bat has extremely sharp front teeth that stick out so that it can use them to make little cuts in an animal’s skin, after first using its teeth to shave the fur down so it can reach the skin more easily. Its fangs lack enamel, so they stay razor sharp. The vampire bat’s saliva contains anticoagulants, so the blood won’t clot right away and the bat can lick it up until it’s full, which takes about 20 minutes. It digests blood extremely quickly, so that it absorbs the nutrients from the blood and starts urinating the extra liquid within a few minutes of starting to feed. That way it can eat more and it can also stay light enough to take flight if it’s disturbed. If you were wondering, its poop is the same as other bat poop. It does echolocate, although not as expertly as bats that eat insects, but the common vampire bat also has specialized thermoreceptors on its nose that sense heat. It’s the only mammal known that can detect infrared radiation, and the only other vertebrates known that can do the same thing are some snakes.

Because vampire bats have to be able to walk around on animals to find a good spot to bite them, the bats have evolved to be able to walk, run, and even jump just fine. Like the pekapeka, it folds the ends of its wings back out of the way and basically walks on the wrists of its wings and its backwards-pointing feet.

Even though the pekapeka and the vampire bat are comfortable running around on the ground, neither has lost the ability to fly. Being able to fly seems to be baked into being a bat. So while it’s not impossible that a bat might eventually become truly flightless, it’s unlikely.

As for bats that are diurnal, or daytime bats, there are a few. A study published in 2018 determined that of the four known species of bat that routinely go out hunting during the daytime, all four live on islands where there are no predatory birds. That doesn’t mean that all bats that live in places where there aren’t any hawks or eagles or crows are active during the day, because most species are still nocturnal, but that seems to be the one requirement for a daytime bat.

John was also interested in learning about the biggest fossil bat ever found. Bats are delicate creatures and don’t fossilize very well, so the bat fossil record is really fragmentary. For example, until 2015 the oldest pekapeka fossil discovered was only 17,500 years old. In 2015, a new fossilized pekapeka ancestor was discovered on the South Island that’s been dated to 16 to 19 million years ago. The fossil shows that the bat was adapted to walk just as the modern pekapeka is, and its teeth are similar so it probably had a similar diet—but it’s estimated to be three times the size of the pekapeka! That sounds like it must have been a huge bat, but the pekapeka only weighs 15 grams at most. That’s barely more than half an ounce, or about the same weight as a CD or DVD, not counting the case. Its ancestor is estimated to have weighed as much as 40 grams, which is almost as heavy as a golf ball. It’s also what a typical vampire bat weighs, if you were wondering.

An even bigger fossil bat has been discovered in a fossil site in France, a country in Europe, and another in Tunisia, a country in North Africa. It’s called Necromantis and is estimated to have weighed as much as 47 grams, which is the same weight as two mice. Two nervous mice, because Mecromantis had strong jaws and big teeth, which suggests it ate small vertebrates–like mice. It lived between 44 and 36 million years ago in areas that were most likely tropical.

An ancestor of the vampire bat was even bigger, possibly as much as 60 grams. That’s just over 2 ounces! That’s a bit heavier than a tennis ball. It lived in South America during the Pleistocene, so recently that in addition to fossils, we also have subfossil remains. That means they’re mineralized but not yet fully fossilized. It’s called Desmodus draculae, and it was most likely still around when humans migrated to South America around 25,000 years ago. Big as it was, it still wasn’t as big as a typical megabat.

Because bat fossils are so rare, it’s led to a scientific mystery. We don’t have any fossils of bat ancestors that weren’t yet bats, but were evolving into bats. In other words, we don’t know what bats looked like before they evolved to be flying animals. The best guess is that the earliest bat ancestors were shrew-like animals that lived in trees and ate insects.

So far we haven’t mentioned any bats that live in Arizona, suggested by Alexandra, so let’s learn about the western red bat. Most bats are black, gray, or brown in color, but the western red bat is a cheerful orange with white shoulder patches and black wing membranes. It’s ready for Halloween all the time! Males are usually more brightly colored than females.

The western red bat lives throughout western North America in summer. It migrates to the southern parts of its range in winter, as far south as Central America. It’s also called the desert red bat but it actually spends most of its life in forests, where its red coat blends in with dead leaves. It eats insects and while it doesn’t spend much time on the ground, every so often it will drop to the ground to catch an insect before hopping back into the air. Not only that, but when the western red bat migrates, it will sometimes fly along with flocks of migrating birds in the daytime.

Unlike many bats, the western red bat is solitary most of the year. Also unlike most bats, instead of having just one baby at a time, it can have up to four babies in a litter. The mother has four nipples instead of just two as in most bats, and for the first three or four weeks of the babies’ lives, the mother has to carry them around while she hunts, until they learn to fly.

As a last note about bats, Murilo specifically mentioned that vampire bats carry diseases that humans can catch. (If diseases bother you, you can stop listening now because we’re almost done.) The common vampire bat does occasionally bite humans, usually the bare big toe of someone sleeping outside, or sometimes the earlobe or even the nose. Vampire bats do show a lot of resistance to blood-borne diseases, but they still spread diseases. The best way to avoid catching a disease from a vampire bat is to not sleep outside without shelter if you can avoid it, if you’re in an area of South America where vampire bats live. That means that if you’re out camping, bring a tent even if it’s hot. Also, avoid eating the meat of wild boar from South America. Not only can boars catch diseases from vampire bats that they pass on to humans, but wild boars also eat fruit partially eaten by fruit bats that also carry diseases. The fruit bats drop partially eaten fruit, the wild boar eats the fruit along with the saliva left on it by the bat, and then the boar can get sick from the saliva.

Most mammals can catch rabies. If you see a bat out in the daytime crawling on the ground, don’t assume that you’re seeing a very rare daytime bat that can also walk around like a pekapeka. Leave the bat alone and contact animal control, because most likely the poor bat has contracted rabies. If you touch the bat, even if it doesn’t bite you, you will have to get a series of rabies vaccines to make sure you don’t come down with rabies, which is an incurable disease and always fatal. That is way scarier than anything else we’ve ever talked about on monster month episodes!

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!