Monthly Archives: November 2020

Episode 200: Elephants

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This week we’re going to learn about elephants! Thanks to Damian, Pranav, and Richard from NC for the suggestions!

Further Reading:

Dwarf Elephant Facts and Figures

An Asian elephant (left) and an African elephant (right). Note the ear size difference, the easiest way to tell which kind of elephant you’re looking at:

Business end of an Asian elephant’s trunk:

An elephant living the good life:

Can’t quite reach:

Elephant teef:

A dwarf elephant skeleton:

An elephant skull does kind of look like a giant one-eyed human skull:

Show transcript:

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

This week we’re going to learn about some elephants! We’ve talked about elephants many times before, but not recently, and we’ve not really gone into detail about living elephants. Thanks to Damian, Pranav, and Richard from NC for the suggestions. Damian in particular sent this suggestion to me so long ago that he’s probably stopped listening, probably because he’s grown up and graduated from college and started a family and probably his kids are now in college too, it’s been so long. Okay, it hasn’t been that long. It just feels like it. Sorry I took so long to get to your suggestion.

Anyway, Damian wanted to hear about African and Asian elephants, so we’ll start there. Those are the elephants still living today, and honestly, we are so lucky to have them in the world! If you’ve ever wished you could see a live mammoth, as I often have, thank your lucky stars that you can still see an elephant.

Elephants are in the family Elephantidae, which includes both living elephants and their extinct close relations. Living elephants include the Asian elephant and the African elephant, with two subspecies, the African savanna elephant and the African forest elephant. The savanna elephant is the largest.

The tallest elephant ever measured was a male African elephant who stood 13 feet high at the shoulder, or just under 4 meters, which is just ridiculously tall. That’s two Michael Jordans standing on top of each other, and I don’t know how you would clone Michael Jordan or get one of them to balance on the other’s head, but if you did, they would be the same size as this one huge elephant. The largest Asian elephant ever measured was a male who stood 11.3 feet tall, or 3.43 meters. Generally, though, it’s hard to measure how tall or heavy a wild elephant is because first of all they don’t usually want anything to do with humans, and second, where are you going to get a scale big and strong enough to weigh an elephant? Most male African elephants are closer to 11 feet tall, or 3.3 meters, while females are smaller, and the average male Asian elephant is around 9 feet tall, or 2.75 meters, and females are also smaller. Even a small elephant is massive, though.

Because of its size, the elephant can’t jump or run, but it can move pretty darn fast even so, up to 16 mph, or 25 km/h. The fastest human ever measured was Usain Bolt, who can run 28 mph, or 45 km/h, but only for very short distances. A more average running speed for a person in good condition is about 6 mph, or 9.6 km/h, and again, that’s just for short sprints. So the elephant can really hustle. Its big feet are cushioned on the bottoms so that it can actually move almost noiselessly. And I know you’re wondering it, so yes, an elephant could probably be a good ninja if it wanted to. It would have to carry its sword in its trunk, though. The elephant is also a really good swimmer, surprisingly, and it can use its trunk as a snorkel when it’s underwater. It likes to spend time in the water, which keeps it cool, and it will wallow in mud when it can. The mud helps protect it from the sun and from insect bites. Its skin is thick but it’s also sensitive, and it doesn’t have a lot of hair to protect it.

The elephant is a herbivore that only eats plants, but it eats a lot of them. An adult elephant eats several hundred pounds of food a day, or more than 100 kg, and will drink enough water every day to fill a bathtub. It eats grass, leaves, twigs, fruit, and bark, and elephants in captivity also eat hay. And since we’re getting close to the winter holidays, some zoos have an agreement with Christmas tree sellers, who donate any unsold Christmas trees to the zoos for the elephants to eat. They can’t feed used trees because there might be leftover ornaments or ornament hangers on them. The elephant just puts one foot on the tree and rips off the branches with its trunk, which it then eats.

The elephant has a pair of big teeth on each side of its mouth that look more like the bottoms of running shoes than ordinary teeth, which it uses to grind up the tough plants it eats. Elephants technically have 26 teeth, two incisors and 24 molars. The incisors are modified into tusks, which we’ll talk about in a minute. The molars aren’t all in the mouth at once, though. Every so many years, the four molars in an elephant’s mouth start to get pushed out by four new molars. It doesn’t happen the same way you lose your baby teeth, though. Instead of a new tooth pushing up through the gum until the baby tooth gets loose and falls out, the new molars grow in at the back of the mouth and start moving forward, pushing the old molars farther forward until they fall out. This happens six times throughout the elephant’s life, with the last set usually growing in around the early 40s. Since elephants can live much longer than that, well into their sixties, that last set may have to last a long time, since there are no elephant dentists that can make gigantic elephant dentures.

The tusks are much different than the molars, naturally. The tusks start to grow from the upper jaw when the elephant is a little over six months old, and continue growing throughout its life. It uses its tusks for all kinds of activities, including moving obstacles from its path, digging for water, and defending itself. But not all elephants have tusks. Many Asian elephants don’t have tusks at all, or only have very small ones. Because poachers who want the tusks to sell as ivory shoot elephants that have the biggest tusks, many populations now have smaller tusks overall or none, since elephants without them are less likely to be killed.

The elephant’s trunk is strong but sensitive, sort of like a human’s arm and hand but with many more uses (and also no bones). The elephant breathes and smells through its trunk, since it’s an extension of the nose and upper lip, but it also makes noise with its trunk to communicate with other elephants, uses it to gather food and move it into the mouth, sucks up water with the trunk and splooshes it into the mouth to drink or onto its body to wash. It can reach plants that are way up high or it can dig into soft ground for roots or to reach water. It can open nuts with its trunk, scratch an itch, play wrestle with a friend, lift incredibly heavy things out of the way, and all sorts of other things. Elephants probably wonder how humans can function without a trunk. I am starting to wonder how I function without a trunk.

The easiest way to tell an Asian elephant apart from an African elephant is by looking at the ears. African elephants have much larger ears, especially savanna elephants. The ears are full of small blood vessels to help release heat from the body into the atmosphere. An elephant will flap its ears to stay cool on a hot day. Asian elephants are also smaller overall and have a different body shape. Asian elephants have somewhat shorter legs, a bulkier forehead, different numbers of toes on the feet, and even different trunks. The African elephant has two little projections at the tip of the trunk that act as fingers, while the Asian elephant only has one.

Elephants evolved in what is now Africa and are the largest land animals alive today. The earliest elephant ancestors lived around 56 million years ago, not long after the extinction of the non-avian dinosaurs. It was still a small animal then, only about a foot tall at the shoulder, or 30 cm. It probably spent a lot of time in the water, eating plants, and it probably had small ears and a large nose, but not an actual trunk. If you could go back in time and look at it, you’d never guess that it was an ancestral elephant.

By 27 million years ago, though, elephant ancestors were starting to look like elephants. Eritreum was a lot bigger, over four feet tall at the shoulder, or 1.3 meters, and it probably had short tusks and a trunk. If you looked at a living Eritreum, you’d definitely know it was a kind of elephant, even though it would have looked weird compared to modern elephants since its head was long and flattened in shape. Eritreum already had the same tooth system that modern elephants have, where new molars continually grow and replace worn-out older ones.

Eritreum’s descendants spread to Eurasia and then to North America. By about 2.5 million years ago, at the beginning of the Pleistocene, elephants were all over the place–not just the ancestors of modern elephants, but relations from other parts of the elephant family tree. This includes Palaeoloxodon, a suggestion by Richard from NC.

Palaeoloxodon namadicus lived throughout much of Asia, with fossils found in India, Japan, and Sri Lanka, and it was enormous. We don’t have a complete skeleton, but estimates of Palaeoloxodon’s size suggest it was the largest elephant that we’ve ever discovered. An estimate of the largest specimen found so far is 17.1 feet tall at the shoulder, or 5.2 meters. This is about the same height at the shoulder as Paraceratherium, which we talked about in episode 50 about tallest animals, but it might have actually been taller than Paraceratherium. The tallest giraffe ever measured was 19.3 feet tall, or 5.88 meters, but that’s at the top of its head, not its shoulder, and giraffes are much less heavy than elephants. Whichever one was actually tallest doesn’t really matter, though, because they all belong to the Ridiculously Tall Animals Club, also known as the Animals That Could Squish You Flat by Accident Club.

We don’t know much about Palaeoloxodon since so few fossils have been found so far. We mostly just know it was a massive animal that probably went extinct 24,000 years ago. That’s really not that long ago in geologic terms. It was probably a member of the straight-tusked elephants, a group of animals that were mostly quite large even for elephants.

Straight-tusked elephants weren’t actually straight-tusked, just straighter than most elephant tusks. They all also had an unusual feature on the head called a parieto-occipital crest, which was a ridge of bone high up on the forehead above the eyes that jutted out. The crest was barely noticeable in young elephants but grew larger as the elephant matured, and researchers think it was the attachment site for massive neck muscles to hold up the animal’s massive head.

One interesting thing about Palaeoloxodon is that some other members of the genus were dwarf species that lived on some Mediterranean islands. Pranav wanted to learn about these and other pygmy elephants of the Mediterranean Islands. Fossil elephants have been found on many islands, including islands in the Mediterranean, in south Asia, and the Channel Islands off the coast of California, although they weren’t all closely related. I think we’ve talked about insular dwarfism before, but let’s go over it again briefly. When a large animal like an elephant becomes restricted to a small environment, like an island, there aren’t enough resources for a full population of full-grown animals. As a result, only smaller individuals get enough food to thrive well enough to reproduce, which means their babies are more likely to be smaller too. Over time this results in a population of animals that are much smaller than their relations who don’t live in a restricted environment.

The opposite of insular dwarfism is island gigantism, by the way. When species that are small ordinarily, like pigeons, colonize an island where there are plenty of resources and very few or no predators, they evolve into much larger animals, like dodos.

Insular dwarfism isn’t just about mammals. Palaeontologists have identified dwarf species of dinosaur too, including a pocket-sized sauropod. Okay, maybe not pocket-sized since they still grew nearly 20 feet long, or 6 meters, but since their mainland relations could grow 100 feet long, or 30 meters, that’s a big difference.

Anyway, back to dwarf elephants. It’s so easy to get distracted by all this neat information. The elephants that lived in the Mediterranean islands were mostly straight-tusked elephants, although at least one was a type of mammoth. During the Pleistocene, when a lot of the world’s water was frozen in enormous glaciers, the sea levels were much lower. This exposed a lot more land, and of course animals lived on that land. Then, during the interglacial periods when much of the ice melted and sea levels rose, animals moved to higher ground and eventually some were cut off from the mainland and lived on islands. All of these species that survived exhibited insular dwarfism. It’s helpful to remember that the islands we’re talking about are mostly pretty big. I mean, they’re not the size of Gilligan’s Island. People live on many of these islands today and there are cities and towns and farms and national parks and so forth. The island of Crete, for instance, which is a part of Greece, is 3,260 square miles in size, or 8,450 square km.

One dwarf elephant that once lived on Crete may have only grown 3.7 feet tall at the shoulder, or 1.13 meters. That was the mammoth relation, but a species of Palaeoloxodon also lived on Crete, although not necessarily at the same time as the dwarf mammoth. As the sea levels rose and fell over the centuries, different species of elephant and other animals ended up living on the islands at different times.

We don’t know a whole lot about these dwarf elephants, unfortunately, since we don’t have a lot of remains. Mostly we have teeth, which do tell a lot about the elephant but not everything. But we do know roughly when the various species finally went extinct, and you will not be surprised to learn that these dates often coincide with human arrival on the islands. The Tilos Island elephant probably didn’t go extinct until 6,000 years ago. That’s well into the modern era, and humans lived or at least hunted on the island starting around 10,000 years ago. If you are Greek, your ancestors may have hunted Tilos Island dwarf elephants. It grew up to around 5 feet 3 inches tall, or 1.6 meters, which coincidentally is my height.

Many historians think that the bones and fossils of dwarf elephants may have led to the legend of the cyclops in ancient Greece. The skull of an elephant has a big opening in the front for the nasal passages, with relatively small eye sockets on the sides of the skull. If you’re not familiar with living elephants and you see an elephant skull, it really does look like an enormous human skull with one eye socket in the middle of the forehead.

All elephants live in small family groups that consist of a leader, called the matriarch, who is usually the oldest female in the group, and her close relations and their babies, usually her daughters and grandchildren. When a young male elephant grows up, he leaves his family group, but daughters usually stay.

Although elephants live in these small groups, they’re social animals. The family groups interact with each other when they meet, and they may meet up purposefully just to say hi. A family with a lot of babies may meet up with another family for help taking care of the young ones. When a member of the group is in estrus, meaning she can get pregnant, local males will join the group and try to get her attention. But although the males don’t spend all their time with family groups, they make friends with other males and sometimes form small bachelor groups of their own led by an older male. The older male not only teaches the younger ones how to find food and react to danger, he keeps them from running wild and acting up. During the 1990s, a nature reserve in South Africa introduced a lot of young males that were orphaned and had no family–but without an older male to keep them in line, they went on a rampage and killed 36 rhinoceroses. Finally the park introduced an older male and he put a stop to all that. The young elephants straightened up and left the rhinos alone.

Females usually come into estrus during the rainy season, which is in the second half of the year in Asia and parts of Africa. During this time, mature males may enter a condition called musth for at least some of the time. During musth a male is more aggressive and struts around showing off. It’s easy to tell when a bull elephant is in musth because a gland on each side of his face releases fluid that makes his cheeks wet. Females prefer to mate with males in musth, and usually in a group of males only the most dominant male will be in musth.

Elephants these days are all threatened by poaching, especially for their tusks. Elephant tusks are known as ivory, and ivory sales are banned throughout most of the world. Unfortunately, people still kill elephants to sell the ivory on the black market. Elephants are also threatened by habitat loss, since they need a whole lot of land to find enough to eat and people want that land for their domestic animals or crops.

I could go on and on about elephants for hours. There’s so much to learn about them that it’s just not possible to fit into one podcast episode. I haven’t even touched on their intelligence, their use as working animals in Asia and other parts of the world, and many other interesting things. But we’ll finish with this interesting fact: elephants are afraid of bees, so farmers can keep elephants from eating their crops by making a fence out of bee hives.

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. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 199: Carnivorous Sponges!

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Thanks to Lorenzo for this week’s topic, carnivorous sponges! How can a sponge catch and eat animals? What is its connection to the mystery of the Eltanin Antenna? Let’s find out!

Further reading/watching:

New carnivorous harp sponge discovered in deep sea (this has a great video attached)

How Nature’s Deep Sea ‘Antenna’ Puzzled the World

Asbestopluma hypogea, beautiful but deadly if you’re a tiny animal:

The lyre sponge, also beautiful but deadly if you’re a tiny animal:

The ping-pong tree sponge, also beautiful but deadly if you’re a tiny animal:

The so-called Eltanin antenna:

A better photo of Chondrocladia concrescens, looking less like an antenna and more like a grape stem:

Show transcript:

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

This week we’re going to learn about carnivorous sponges, which is a suggestion from Lorenzo.

When I got Lorenzo’s email, I thought “oh, neat” and added carnivorous sponges to the giant, complicated list I keep of topic suggestions from listeners and my Aunt Janice, and also animals I want to learn more about. When I noticed carnivorous sponges on the list the other day, I thought, “Wait, sponges are filter feeders. Are there even any carnivorous ones?”

The answer is yes! Most sponges are filter feeders, sure, but there’s a family of sponges that are actually carnivorous. Caldorhizidae is the family, and it’s made up of deep-sea sponges that have only been discovered recently. We know there are lots more species out there because scientists have seen them during deep-sea rover expeditions without being able to study them closely.

We talked about sponges way back in episode 41, with some mentions of them in episodes 64 and 168 too, but only the filter feeder kind. Let’s first learn how a filter feeder sponge eats, specifically members of the class Demosponge, since that’s the class that the family Caldorhizidae belongs to.

Sponges have been around for more than half a billion years, since the Cambrian period and possibly before, and they’re still going strong. Early on, sponges evolved a simple but effective body plan and just stuck to it. Of course there are lots and lots and lots of different species with different shapes and sizes, but they almost all work the same way.

Most have a skeleton, but not the kind of skeleton that you think of as an actual skeleton. They don’t have bones. The skeleton is usually made of calcium carbonate and forms a sort of dense net that’s covered with soft body tissues. The tissues are often further strengthened with small pointy structures called spicules. If you’ve ever played a game called jacks, where you bounce a ball and pick up little metal pieces between each bounce, spicules sort of resemble jacks.

The sponge has lots of open pores in the outside of its body, which generally just resembles a sack or sometimes a tube. One end of the sack is attached to the bottom of the ocean, or a rock or something. The pores are lined with cells that each have a teensy structure called a flagellum, which is sort of like a tiny tail. The sponge pumps water through the pores by beating those flagella. Water flows into the sponge’s tissues, which are made up of lots of tiny connected chambers. Cells in the walls of these chambers filter out particles of food from the water, much of it microscopic, and release any waste material. The sponge doesn’t have a stomach or any kind of digestive tract, though. The cells process the food individually and pass on any extra nutrients to adjoining cells.

Obviously, this body plan is really effective for filter feeding, not so effective for chasing and killing small animals to eat. The sponge you may have in your kitchen is probably synthetic or manufactured from a sponge gourd, not an actual bath sponge animal, but it’s arranged the same way. Go look at that sponge, or just imagine it, and then compare it mentally to, say, a tiger. Very different.

But in 2007, an underwater rover captured something on film that astounded researchers. The rover was investigating some undersea caves in the Mediterranean, where a tiny sponge known as Asbestopluma hypogea lives. The sponge only grows about half an inch long, or 1.5 cm, and everyone assumed it was just a regular old sponge. You know, a filter feeder. It did have an unusual structure of filaments covered with hook-like spicules, but until 2007 no one realized those spicules were actually hooks and used to snag tiny animals like copepods, nematodes, and even brittle stars. Then they saw it on film and freaked out! Well, they probably freaked out. I like to think they did.

But wait, you are probably saying, or at least thinking, sponges don’t even have a digestive system! How do they eat the animals they catch?

It works like this. When a tiny animal floats or swims past and gets snagged by the hooked spicules, which by the way is a passive process, the sponge starts growing a membrane that envelops the animal within a few hours. The membrane is made up of specialized cells that contain beneficial bacteria, and the bacteria help digest the animal so that the cells can absorb the nutrients. The process can take up to ten days. It’s similar in some ways to how carnivorous plants digest animals, as we talked about in episode 129.

One interesting thing is that while A. hypogea is a deep-sea sponge, it’s also found in shallow underwater caves. Further research has suggested that underwater caves may shelter other animals that are usually deep-sea dwellers. One cave where the sponge is found is only 16 feet below the surface, or five meters, whereas it lives around 2,300 feet deep, or 700 meters, in open ocean. Since its discovery in both the caves and in deeper parts of the Mediterranean, it’s been classified as a protected species and parts of the Mediterranean where it lives have also been protected.

It wasn’t until 2012 that the harp sponge was discovered off the coast of northern California. The harp sponge lives up to 11,500 feet below the surface, or 3,500 m, and it gets its name because of its shape. Like a harp, which has strings stretched down from an arched frame, the harp sponge has a structure called a vane that consists of a horizontal branch with straight, thin branches growing up from it in a row. The harp sponge can have up to six vanes, and where they connect in the middle the sponge has root-like filaments that anchor it to the sea floor. It’s no wonder that people used to think sponges were plants.

The vanes of the harp sponge are covered with hooked spicules like the grabby half of Velcro, but pointier. At the top of the vertical branches, little balls of sperm form and are released into the water to fertilize the eggs of other harp sponges. The sponge also has egg development areas about halfway up the vertical branches, which have tiny filaments to help it catch sperm released by other sponges. When it catches sperm, the cells of the filament fuse with it and use it to fertilize the nearest eggs. You can see both the sperm packets and the egg development areas in a picture in the show notes, and both look like little bulbs.

I should mention that all these carnivorous sponges are incredibly pretty.

The harp sponge can grow up to almost 15 inches across, or 37 cm, which is pretty big for a sponge.

The ping-pong tree sponge is another newly discovered carnivorous sponge, and arguably it has the best name. It can grow up to 20 inches tall, or 50 cm, but most of its height comes from its central stalk that anchors it to the sea floor. At the top of the stalk, smaller stems branch out and at the end of the stalks, little bulbs around 3 to 5 mm in diameter grow like grapes on a grape stem. The bulbs resemble little ping-pong balls (also known as table tennis, but ping-pong is funnier and refers to the sound the little hollow ball makes as it bounces from a paddle and off the table).

We don’t know much at all about the ping-pong tree sponge. It’s been found off the coast of South America near Easter Island, around 8,800 feet deep, or 2,700 meters. So far it seems to live in areas where the sea floor is made up largely of hardened lava.

We’ll finish with a mystery related to carnivorous sponges! In 1964 a research ship called the USNS Eltanin was photographing the sea floor in the Antarctic, and on August 29th it took a photograph of something weird off the coast of Cape Horn. Cape Horn is the very southern tip of South America except for a few islands, and is considered the point where the Atlantic and Pacific Oceans meet. That’s an arbitrary distinction made by humans since obviously the world’s oceans are connected everywhere, but it’s useful for telling people where you found a weird thing in the water. The picture was taken at a depth of almost two and a half miles, or 3,904 meters.

The picture shows what looks like a stick growing straight up from the ocean floor, with cross-shaped pieces of equal lengths sticking straight out to the sides, and a little bulb at the very top. It looks for all the world like a weird radio antenna, and it’s actually been called the Eltanin antenna.

The picture appeared in a newspaper article later that year, 1964, and drew the attention of UFO enthusiasts. By 1968 many people thought the picture showed a piece of machinery left by alien visitors for unknown but probably sinister purposes, although why they left the machinery at the bottom of the ocean, no one could say. Other people thought the antenna had been planted by the Soviets for likewise unknown but probably sinister purposes, ditto no idea why it was at the bottom of the ocean. Other people pooh-poohed all that and said it was probably just something that had fallen off a ship and lodged upright in the mud.

Instead, it turns out that the so-called antenna is probably actually a carnivorous sponge, Chondrocladia concrescens, known to science since 1880 although no one knew it was carnivorous back then. Disappointingly, better pictures of the sponge show that it looks more like a grape stem than an antenna. These days even diehard UFO researchers acknowledge that the Eltanin antenna was just a sponge, although a pretty neat one. Mystery solved!

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. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 198: Pop Goes the Mustelid

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Let’s learn about a whole lot of mustelids, including some otters, weasels, and their relations and ancestors! Thanks to Jacob for the suggestion!

Further reading:

Weasels in Stone: Mustelid Evolution

With voices joined in chorus, giant otter families create a distinct sound signature

Further watching/listening:

Video of giant river otters making noise

Giant river otters:

The least weasel is possibly the most cute:

This mink would like to keep its fur for itself please and thank you:

The Patagonian weasel:

The greater grison looks like a badger and a honey badger:

The fisher:

The Chinese ferret badger has a long nose compared to most mustelids:

Show transcript:

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

This week we’ll learn about some mustelids, better known as weasels and their close relations! Thanks to Jacob for this week’s suggestion.

The weasel is a member of the family Mustelidae. Members of the family are called mustelids, which includes wolverines and badgers, which we talked about in episode 62, otters, which we talked about in episode 37, and ferrets, which we talked about in episode 150. Most mustelids have short legs and long, slender, flexible bodies, although badgers are an exception since they’re broad-bodied. This body shape allows a mustelid to enter the burrows of other animals and kill them, because mustelids are carnivores.

But not all animals that look like weasels and ferrets are actually mustelids. The mongoose, for instance, is not a mustelid.

The study of how mustelids evolved and spread throughout much of the world is a pretty hot topic these days, which makes it confusing to summarize since so much new knowledge keeps shaking up what we know. But I’ll do my best.

The first mustelids evolved around 30 million years ago in what is now Eurasia, and spread to North America much later and eventually into South America. The oldest mustelid fossils found in North America are a group of animals called oligobunines. I read that word as oligobunnies every single time, but they didn’t look like bunnies. They probably looked like wolverines, which are related to badgers but look more like miniature bears with longer tails, but they probably spent more time underground than wolverines do.

At least one oligobunid might have grown as big as a black bear, at least a small bear. Megalictis was probably an ambush predator and lived around 21 million years ago in what is now the upper Midwest of North America. It had teeth meant for crushing bones. Another oligobunid, Zodiolestes, is one we talked about briefly in episode 103, about trace fossils. The first fossil Zodiolestes was found in a corkscrew-shaped Palaeocastor burrow, presumably because it got stuck in the burrow while it was hunting, but Zodiolestes was also adapted to dig. The oligobunids went extinct around 10 million years ago, possibly outcompeted by a new wave of modern mustelids that evolved in Asia and spread into North America.

One mustelid, Ekorus ekakeran, lived about six million years ago in what is now Africa, with fossils found in Kenya. But it didn’t look like any other mustelid. It had long legs, for one thing. It stood almost two feet tall at the shoulder, or 60 cm, and was built more like a leopard than a mustelid. It would have been a much faster runner than other mustelids as a result, although it was probably an ambush predator. Researchers think it was eventually outcompeted by big cats when they evolved as the forests changed into grasslands.

The biggest mustelid that ever lived, as far as we know, is Enhydriodon, a type of gigantic otter. It lived in Africa around 4 million years ago and may have been the size of a small bear, even bigger and heavier than Megalictis. We only have a single fossil of Enhydriodon, though, a skull, so scientists can only estimate the animal’s size compared to what we know about extinct and living otters. It probably lived on land, although that’s about as far as our knowledge of it goes.

Another giant mustelid was Plesiogulo, which evolved in Asia and crossed into North America 6 1/2 or 7 million years ago when the continents were connected by the Bering land bridge. Researchers weren’t sure for a long time if Plesiogulo was directly ancestral to living wolverines, but recent studies indicate that it probably was. It was larger than modern wolverines.

But what about living mustelids? The biggest known mustelid that’s still alive is the giant otter, which lives in much of northern and central South America, especially around the Amazon River, although it’s increasingly rare due to habitat loss, hunting for its fur, and pollution. It can grow up to 5 1/2 feet long, or 1.7 meters. It mostly eats fish but will eat other animals too, including crabs, snakes, turtles, and even small caimans. It’s a social animal that lives in family groups of up to twenty members that hunt and play together. It has short dense fur that’s usually brown or sometimes reddish, but it has white markings on its throat and upper chest. When it pops its head and neck out of the water, called periscoping, other otters can see its unique white markings and recognize who they’re looking at. It’s also really noisy as it communicates with other otters with barks, whines, growls, and softer sounds like humming. Each family group has a unique vocalization that identifies the group to other otters, and if a strange otter approaches the territory the whole family will scream at it to get out or else.

The sea otter is a little shorter than the giant otter, just under 5 feet long, or 1.5 meters, but it’s heavier than the giant otter. A big male can weight up to 119 pounds, or 54 kg. It lives along the coast of the North Pacific and while it can walk, it spends almost all its time in the water. Instead of blubber to keep it warm, the sea otter has incredibly dense fur, the densest coat ever measured. For almost two centuries people hunted it so aggressively for its fur that by 1911, there were fewer than 2,000 of them left. Fortunately, conservationists worked to get an international ban on sea otter hunting, and its numbers have rebounded although it’s still endangered.

The sea otter eats fish and anything else it can catch, especially shellfish, and it uses its front paws while hunting. It catches fish with its paws instead of with its mouth, it turns over rocks to look underneath them, and it pulls mollusks off of rocks and twists them open with its paws. This is all really unusual. No other otter uses its paws in this way. Not only that, the sea otter is a tool-user. It uses rocks to break open shellfish that it can’t twist open or bite through, and will in fact use two rocks at once for this purpose. One of the rocks it holds, but the other it keeps in a little pouch of skin under its arms to act as a hard surface to set the mollusk on. The sea otter also uses this built-in pocket to hold food. It has two pockets, one under each front leg, and it usually keeps its rock in the right pocket while it keeps its food in the left pocket. It floats on its back to eat, then rolls over and over in the water to clean its fur of any bits of food. It has to keep its fur incredibly clean for it to insulate the otter properly, so it grooms itself throughout the day. Pascal in Animal Crossing is a sea otter, by the way, and adorable.

The smallest living mustelid is the least weasel, which is native to northern North America and much of Eurasia but has been introduced in New Zealand and several islands throughout the world, where it’s an invasive species. The smallest subspecies of least weasel grow less than 10 inches long, or 26 cm, with a short tail. It’s brown with a white belly during the summer but its winter coat is completely white. It eats mice, voles, and other small rodents and will even kill rabbits although rabbits are much bigger than it is. Generally it only attacks young rabbits, though.

So that gives us some background about mustelids. Let’s talk about some interesting kinds of mustelid next, starting with the mink. You may have heard something about the mink in the news lately, because mink are kept in large numbers in fur farms and they’ve started to contract a mutated version of the Covid-19 virus. The virus is so widespread among mink in the country of Denmark that as of last week as this episode goes live, Denmark has decided to kill every single mink in captivity. That’s as many as 19 million animals. Keep in mind that these animals were eventually going to be killed anyway for their fur. That doesn’t make it any less sad, though. The same mutated virus has spread through fur farms in other countries, including Spain and the United States, leading to thousands of animals being killed to stop the spread. So far studies do not indicate that the minks are spreading the mutated version of the virus to humans. The Netherlands had already been planning to ban mink farming in a few years, but after an outbreak of the coronavirus earlier in 2020 the country decided to ban it by the end of this year. Good for them.

In the wild, where it belongs, the mink lives near rivers, lakes, or other sources of fresh water, and sometimes even along the coast. It eats fish, rabbits and other small mammals, eggs, small crustaceans like crayfish, and anything else it can catch. A big male can grow up to two feet long, or 62 cm, and it’s brown in color with a dense undercoat that helps keep it warm in cold weather. There’s a species that lives in North America and a species that lives in Europe, but while they look almost identical, they’re actually not very closely related.

If you think of weasels, you probably think of an animal that looks a lot like the mink or the ferret, with sleek fur. But the Patagonian weasel is quite different in many ways. It lives in Patagonia, which is the southern part of South America, and is the only member of its own genus. Its coat is shaggy with a bushy tail. It’s mostly white or off-white with brown patches and grows up to 14 inches long not counting its short tail, or 35 cm. We know almost nothing about the Patagonian weasel. We’re not even sure what it eats, except that it does probably eat small burrowing rodents, and it’s sometimes been kept by ranchers to kill rats the way ferrets were once used in England.

The greater grison is another unusual-looking mustelid native to Central America and northern South America. It’s shaped sort of like an otter but instead of brown fur it’s gray on top and black underneath. A white stripe separates the gray and black fur on its head and the sides of its neck. Most of its face is black, then the white stripe usually just above the eyes, then gray on top of its head. It can grow up to two feet long, or 60 cm, not counting its bushy tail, which can grow up to 14 inches long, or 20 cm. Like all mustelids, its ears are small and round and its body is long with short legs. Although it looks like an otter, including having webbed toes, it’s probably more closely related to the Patagonian weasel, and like the Patagonian weasel, we don’t know a whole lot about it.

The fisher is a mustelid that lives in North America, mostly in parts of Canada and in mountainous areas of northern and western United States. It used to be more widespread, but, you guessed it, it was trapped and killed for its fur until the 1930s and even as late as the 1980s in some areas.

Despite its name, the fisher doesn’t actually eat fish very often. The name fisher comes from a Dutch word, visse, which refers to a different mustelid, the European polecat. The fisher is also sometimes called the fisher cat even though it and the polecat are not cats. It’s a big animal, too. A big male fisher can grow nearly four feet long, or 1.22 m, although females are much smaller, and part of that length is the tail that can be as much as 16 inches long, or 41 cm.

The fisher has big feet that helps it walk on snow, retractable claws, and it can even rotate its hind feet nearly completely backwards, which means it can climb down trees headfirst. It lives in forests and spends a lot of time in trees, hunting birds and other small animals, but it mostly eats showshoe hares and porcupines. Yes, porcupines! Almost nothing will bother a porcupine, but the fisher will attack it from the front, biting its less protected face repeatedly until it dies. In areas where fishers were hunted to extinction, porcupines became so numerous that they started killing trees, since in winter porcupines eat tree bark and will also eat sapling trees. Fortunately, the population of fishers has grown and conservationists have reintroduced it into parts of its former range. It’s no longer considered endangered, hurrah! This is good because they’re hard to keep in captivity and they’re also susceptible to accidental poisoning when they eat rodents that have died from eating poison.

The fisher is supposed to be a loud animal with a terrifying scream at night, but people who study fishers don’t report hearing them scream or make loud sounds at all. The calls are all probably made by the red fox, which sounds like this:

[fox sound]

There are so many mustelids that I don’t even know what other ones to feature. It’s surprising how little we know about so many of them. The Vietnam ferret-badger was only described in 2011, for instance, and only known from two specimens. It’s related to other ferret-badgers found in Asia, including the Chinese ferret-badger. As you might guess from the name, it looks sort of like a badger but also like a ferret, which is a neat trick because those two animals do not actually look very much alike. It grows around 17 inches long, or 43 cm, plus another 9 inches, or 23 cm, for its tail. It’s dark brown above and lighter brown underneath, with a white stripe on its head and neck and a black mask on its face. Its muzzle is longer than most mustelids’, who usually have quite short noses. It’s an omnivore that eats fruit as well as insects, worms, frogs, and other small animals.

In general, as I’ve mentioned over and over, mustelids have historically been killed for their fur. Sable and ermine are both names of furs that come from mustelids. At least one species was driven to extinction by fur hunters, the sea mink. It lived along the northeastern coast of North America and was related to the American mink. We don’t even know exactly how big it was, because it was driven to extinction before it could be examined by scientists, except that it was probably bigger than the American mink. We don’t even have a complete specimen, just some skull fragments and teeth. It wasn’t as aquatic as otters are, but it occupied a similar ecological niche and spent much more time in the water than its close relations. It probably went extinct in the late 19th century. Other species of mustelid may have been driven to extinction without ever being known to science too. Certainly many species came close to extinction and are still threatened by habitat loss and other factors.

That’s depressing to think about, so let’s finish with a mystery that’s a little different from our usual mystery animals. This one’s a mystery song called “Pop Goes the Weasel.” You’re probably familiar with the tune even if you’re not sure about the words. There are lots of different lyrics to the song with various versions in different places. I learned it this way:

Round and round the mulberry bush / The monkey chased the weasel / The monkey stopped to pull up his socks / Pop! Goes the weasel.

A penny for a spool of thread / A penny for a needle / That’s the way the money goes / Pop! Goes the weasel.

What on earth do those lyrics mean? Do they mean anything? Why is there a weasel in the song?

The earliest lyrics known date back to at least the early 19th century in England, because the oldest versions of the song reference a famous pub in London from the time. The melody was probably much older and the words were fitted to the song at some point. By 1850 it was a popular dance, but even then no one knew what the lyrics meant.

There are lots of suggestions, some of which make more sense than others. The oldest lyrics seem to be these:

Half a pound of tuppenny rice / Half a pound of treacle / That’s the way the money goes / Pop! Goes the weasel.

Up and down the City road / In and out the Eagle / That’s the way the money goes / Pop! Goes the weasel.

The line “that’s the way the money goes” basically tells the story. It’s a song about how everything is a penny here, a penny there, and suddenly you’re broke. And if you’re going in the Eagle Tavern on London’s City Road too often, you’re drinking up whatever money you have left. But that still doesn’t explain the weasel.

One explanation is that to pop something was slang for pawning it, and that the term weasel is Cockney rhyming slang for a coat. You know, “weasel and stoat” rhyme with coat, therefore you can just say weasel and everyone who knows the rhyme knows that you’re talking about a coat. So if you pop a weasel, you’re pawning your coat to get a little extra money.

This sounds plausible, and there’s some evidence that the line “pop goes the weasel” was the only line of the song originally, with the other lyrics added later, which would explain why that one line is slang while the other lines aren’t. Anyway, it’s a fun song that you will not be able to get out of your head now.

You can find Strange Animals Podcast online 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. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend.

Thanks for listening!

Episode 197: Titanoboa!

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Thanks to Pranav for this week’s suggestion, Titanoboa, the biggest snake that ever lived!

Parts of this episode come from an old Patreon episode about super-gigantic snakes, which is unlocked and you can listen to it here.

A modern anaconda vertebra next to a Titanoboa vertebra. Guess which one is which:

Carlos Jaramillo, one of the scientists who found Titanoboa and Acherontisuchus (taken from a Smithsonian Channel video):

Show transcript:

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

This has been a really busy week for me and I wasn’t able to finish researching the episode I had planned. Instead, we’ll have a short episode on a topic Pranav suggested ages ago, TITANOBOA! In September 2017 I released a Patreon episode about giant snakes, including Titanoboa, but this episode is all new. Ha ha, I thought it would take me less time to research it than finishing the research for what will be next week’s episode, ha ha I was wrong. Anyway, I’m going to unlock the giant snakes Patreon episode so anyone can listen. There’s a link in the show notes if you want to click through and listen on your browser.

Oh, a big congratulations to the winner of my book giveaway, Arthina! Thanks to everyone who entered.

In 1994, a geologist named Henry Garcia found an unusual-looking fossil in northeastern Colombia in South America. Specifically, it was an area that had been strip-mined for coal. Fifty-eight million years ago the region was a hot, swampy, tropical forest along the edge of a shallow sea. The Andes Mountains hadn’t yet formed. The environment was probably most similar to the Everglades and the Mississippi River delta in North America, but the climate was much warmer than it is now. These days what was once swamp is a field of rock uncovered by coal mining, which is not good for the environment but is unbelievably good for palaeontology.

Garcia thought he’d found a piece of fossilized tree. The coal company in charge of the mine displayed it in their office along with other fossils. And there it sat until 2003, when palaeontologists arranged an expedition to the mine to look for fossil plants. A researcher named Scott Wing was invited to join the team, and while he was there he poked around among the fossils displayed by the mining company. The second he saw the so-called petrified branch he knew it wasn’t a plant. He sent photos to a colleague who said it looked like the jawbone of a land animal, probably something new to science.

In 2007, the fossil was sent for study, labeled as a crocodile bone. But the palaeontologists who examined the fossil in person immediately realized it wasn’t from a crocodile. It was a snake vertebra—but so enormous that they couldn’t believe their eyes. They immediately arranged an expedition to search for more of them, and they found them! Comparisons to living anacondas and boas, the snake’s closest living relatives, helped researchers estimate the snake’s size. They named it Titanoboa cerrejonensis and described it in an article published in 2009 in Nature.

In 2012, a partial Titanoboa skull was found. Snake skulls are fragile and don’t fossilize nearly as often as the more robust vertebrae and ribs. It turned out that Titanoboa had lots and lots of teeth, more teeth than modern boids have.

Palaeontologists have found fossilized remains from around 30 individual snakes, including young ones. The adult size is estimated to be 42 feet, or 13 meters. The largest living snakes are anacondas, which may grow up to 29 feet, or 8.8 meters, but which are usually less than half that length. Reticulated pythons grow up to about 26 feet, or almost 8 meters, and possibly longer, but are also usually less than half that.

Titanoboa might have grown up to 50 feet long, or 15 meters, and could weigh more than 2,500 pounds. That’s one and a quarter tons, or more than 1100 kg. The thickest part of its body would have been waist-high compared to an average human male. Of course, these are all estimations since we don’t have a complete skeleton or a living specimen to examine, and most estimates these days put the maximum length at around 42 feet, or 13 meters. Still humongous. Females were probably larger than males, as is the case with most snakes.

Once the skull was found containing all those little teeth, researchers determined that Titanoboa probably ate a lot of fish. That’s unusual for constrictors, but it makes sense to think that a snake that large, living in a hot, tropical area, would spend most of its time in the water.

Even though snakes are cold-blooded, which means their internal temperature fluctuates with the temperature of their environment, a snake that size would retain a lot of heat and even generate heat from metabolic processes. Metabolic processes are related to digestion, chemical reactions that break down food into nutrients that can be used by the body. This releases heat, and in an animal with a bulky body that heat is retained more than in an animal with a slender body. Titanoboa was so big that some researchers think it would have overheated from its own metabolic processes if it didn’t stay cool somehow. Therefore, it might have lived in deep water where it could stay cool. Modern anacondas spend most of its time in the water, although usually in the shallows where it can hide in wait for prey.

Titanoboa undoubtedly ate a type of lungfish that grew nearly ten feet long, or 3 meters, but it probably also ate anything else it could catch, including crocodilians. A gigantic crocodilian found in the same area as Titanoboa, Acherontisuchus, grew up to 21 feet long, or almost 6.5 meters. It lived in the water too and probably mostly ate fish, but it didn’t so much compete with Titanoboa as avoid it as much as possible. After all, a full-grown Titanoboa was more than twice the size of a full-grown Acherontisuchus and could have swallowed it whole after suffocating it.

Several gigantic freshwater turtles also lived alongside Titanoboa. One had a shell that measured 5 feet 8 inches long, or 1.72 meters. Another grew five feet long, or 1.5 meters, but had a shell that was almost perfectly round. Researchers think its shape kept it safe from Titanoboa, since it would have been too big for Titanoboa to swallow. Snakes have bones and jaws that can dislocate to allow them to swallow large prey whole, and stretchy skin, but they have limits. Another turtle had a shell that was described as being as thick as a dictionary. Since other crocodilians have since been found in the area too, the thick shell was probably a defense against crocodilian jaws and teeth. Basically, this was a dangerous place to live no matter how big you were, unless, of course, you were a gigantic snake.

Titanoboa and the other animals of the swampy rainforest lived only about ten million years after the extinction event that killed off the non-avian dinosaurs. Obviously they’d been evolving to fill ecological niches left empty by the dinosaurs. Little did they know, though, that continental drift would lead to a cooling climate that would drive many reptiles to extinction and give rise to the age of mammals!

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. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us that way.

Thanks for listening!

Episode 196: Many Monkeys

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Thanks to Nick and Richard from NC for their suggestions this week! Let’s learn about A BUNCH OF MONKEYS!

Further reading:

How we solved the Green monkey mystery–and found an important clue to Bronze Age world

Field Notes: Singing Titi Monkeys (with a video of them singing)

Dracula monkeys and Dracula:

The Dracula monkey orchid (not a vampire, not a monkey, but it is an orchid):

A capuchin monkey insisting a friend “see no evil”:

Abu!

Mandrills gonna get as colorful as monkily possible:

Rafiki! Why is your tail so long?

One of the “blue monkey” wall frescos and some grey langurs:

The fluffy titi monkey:

Show transcript:

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

Halloween is over for another year, but that doesn’t mean things get boring. This week let’s learn about some monkeys, including a few monkey mysteries that were solved with science! Thanks to Nick and Richard for their suggestions.

We’ll start with the Dracula monkey, suggested by Richard from North Carolina, who also sent me an article a while back about the monkey. I meant to include this topic in an episode before October but got distracted by all the other awesome animals that have been suggested lately.

The Dracula monkey is also called Miller’s Grizzled langur, but that’s a mouthful and Dracula monkey is funnier. It’s not called the Dracula monkey because it has fangs, but because its body is gray with a white ruff that sticks out on either side of the neck like the collar of Dracula’s cape in the movies. Its face is also gray except for a white U-shaped marking under its nose like a little white mustache. It grows up to 22 inches long, or 56 cm, not counting its tail which is even longer than its body.

The Dracula monkey eats young leaves and unripe fruit, along with flowers, seeds, and sometimes eggs. It spends most of its time in trees and is endangered by habitat loss and hunting, and it only lives in one place, in rainforests on the island of Borneo in South Asia. It was spotted by scientists in 2012 after it was suspected to be extinct, but that was the last anyone saw of it for years.

An Animal Planet show called “Extinct or Alive” was filming in Borneo in spring of 2019, unless it was 2018, it’s not clear from the article, searching for the Dracula monkey. The host and his team set up camera traps in the forest, braving literally hundreds of bee stings as they did so. But it worked, catching the monkey on camera and proving it wasn’t extinct. When an animal is declared extinct, conservationists lose funding to help it and it’s removed from the list of protected animals, so it’s important to search for animals that are suspected to be extinct but might not be.

While I was researching the Dracula monkey, I learned about a rare orchid called the Dracula monkey orchid. It has fuzzy reddish-brown and white flowers that look remarkably like a monkey’s face. It doesn’t actually look like Dracula or a Dracula monkey, though. Who names these organisms? In this case, scientists. The orchid’s scientific name is Dracula simia, and the genus Dracula is named because some of the orchids in the genus are red or black and white and the long spurs supposedly hang down like fangs. The Dracula monkey orchid is found in southeastern Ecuador in South America, and only grows in moist high-altitude forests. The flowers smell like oranges. This has been your bonus plant fact of the week.

The Dracula monkey orchid actually looks more like a capuchin monkey than a Dracula monkey, so let’s learn about the capuchin next.

You probably know what the capuchin monkey looks like because it’s so common in movies. The monkey in Raiders of the Lost Ark (you know, the “bad dates” monkey) was a capuchin, but the noises he makes in the movie are actually voiced by a human actor named Frank Welker. Welker also voiced the monkey Abu in Disney’s Aladdin from 1992. In the live-action remake from 2019, he’s still a capuchin but computer-animated.

The capuchin monkey lives in forests in Central and South America, but there are lots of species. Most are dark brown with cream-colored markings on the face and around the neck. It lives in trees and unlike many monkeys, it’s an omnivore. It eats leaves, fruit, nuts, flowers, and other plant parts, but it also eats insects, frogs, crabs, shellfish, and other small animals. It’s about the same size as the Dracula monkey, up to 22 inches long, or 56 cm, with a tail the same length as the body.

The reason so many capuchin monkeys are used in movies and TV shows is because they’re one of the most intelligent monkeys known, social, adaptable, and easy to train. But they’re wild animals and they don’t make great pets. They can be dangerous if they’re upset, and to be happy they need the company of other capuchin monkeys in a situation as much like their social structure in the wild as possible. In the wild, the capuchin lives in groups of up to 35 individuals that travel around the group’s territory throughout the day, looking for food. Their social structure is complicated, which is usually the case with intelligent animals, and members of the group interact constantly, whether they’re grooming each other, playing, gathering food, or watching for danger.

The capuchin monkey is a tool user, which was well known to locals but wasn’t observed in the wild by scientists until 2004. It uses rocks to break open shellfish and nuts, and it will use different sized rocks to break different kinds of nuts. For really hard nuts it will use large, heavy rocks, but for smaller nuts it will use a smaller, lighter rock. This sounds like a duh moment, but that’s because humans are the ultimate tool users and we understand that of course you shouldn’t smash open a cashew with a gigantic rock because you’d just pulverize the nut, while tapping at a really hard nut with a little pebble won’t do anything to break it open.

Not only do the capuchin monkeys in Brazil use different sized rocks to break open nuts, they select the rocks carefully and prefer ones that are rounded and easy to handle. They’re called cobbles. They set the nuts on a hard surface like another rock or an exposed tree root and use the cobbles to break the nuts open.

In 2016, researchers chose a site where capuchin monkeys have been using these stones to open nuts for many years. They treated it as an archaeological site and excavated it by digging carefully and documenting what they found. They found that the site had been used for at least 3,000 years, with some evidence that the monkeys’ diet had changed from eating smaller nuts to larger, harder nuts. Researchers aren’t sure if the diet change came from changes in the foods that were available or if the monkeys became better at breaking open hard nuts so were able to eat more of them.

This is what a capuchin monkey actually sounds like, including the little birdlike trills:

[monkey sounds]

Nick suggested that we learn about the mandrill, so let’s do that next. The mandrill is a big monkey that lives in forests and rainforests in parts of the west coast of central Africa. Not only is it a big monkey, it’s the biggest monkey, or at least the heaviest. Males are much larger than females and a big male can weigh as much as 119 lbs, or 54 kg, and possibly more. It’s a muscular, compact animal that looks more like an ape than a monkey, and it spends most of its time on the ground instead of in trees. It’s dark gray or greeny-brown with a white belly, a long muzzle, and a little stub of a tail.

And, of course, the mandrill is really colorful. A dominant male develops bright blue and red markings on his muzzle and blue, pink, and purplish colors on his bare bottom. Females and subordinate males are less colorful. During mating season, females who are in estrus, which means they’re fertile and can have a baby, develop enlarged red bottoms to attract a male.

All this is interesting, and cheerfully colorful, but if you stop and think about it for a moment, how many mammals can you think of that have skin that is bright blue or purple? Not very many. For a long time researchers weren’t sure what caused the color. It’s not a pigment, so it has to be caused some other way. The blue coloring of many birds is caused by the way light reflects off the black pigment in the feathers. It turns out that in mammals with blue and purple skin, the same is true. Skin contains a protein called collagen, which is very tough and which grows in a random pattern. But in the areas where a mandrill’s skin is blue or purple, the collagen fibers grow in a parallel pattern. This means that when light reflects off the skin, only the blue wavelengths of light bounce off. The other wavelengths are canceled out. The closer together the collagen fibers are, the brighter the blue.

The mandrill lives in much larger groups than other monkeys do, sometimes numbering several hundred. One group had over 1,300 members. Generally, each group is made up of females and their babies, with a dominant male that lives on the outskirts of the group most of the time. The exception is during mating season, which lasts from June to October. During this time the females allow males to join the group so they can mate. A female usually only has one baby every two years, and a mother mandrill’s female relatives help care for the baby. When male babies grow up they leave the group and live on their own, while females remain in the group.

The mandrill is an omnivore although it most eats fruit and other plant material, but it will eat insects and other invertebrates, eggs, and small vertebrates like frogs, rats, and birds. It has long canine teeth that help it kill small animals and even larger animals if it can catch them. It even has cheek pouches so it can carry food around to eat later. It mostly feeds on the ground but will climb trees to get food and it also sleeps in trees at night.

Since we were talking about movie monkeys earlier, the character of Rafiki in the Lion King is a mandrill.

Next, let’s look at a couple of monkey mysteries that were recently solved. The Greek island of Santorini, once called Thera, is famous for its murals, which were uncovered by archaeologists around 50 years ago and are studied to learn about the people who lived on the island 3,600 years ago. The frescos, or wall paintings, were preserved by volcanic ash that destroyed the city of Akrotiri. Some of the frescos depict monkeys of various kinds, including one type of monkey that’s been a mystery for years. Historians assumed the monkeys had to be from Africa, since the Aegean people of the island traded with Egypt. But the paintings didn’t quite match any monkey known from Africa. Finally, the historians studying the frescos called in some primatologists to see if they could figure out the mystery.

The monkeys are depicted as blue-grey with long tails carried upward in a curve like a big question mark. This detail gave the primatologists the clue they needed. The mystery monkeys were Hanuman langurs, also called the gray langur, which carry their tails in exactly this way. They’re from India, not Africa, which means that the Aegeans must have had trade routes that were far more extensive than previously known.

The gray langur lives throughout the Indian subcontinent and there are several species. They mostly eat leaves, along with seeds, lichen, fruit, moss, and lots of other plant materials, but they’ll occasionally eat insect larvae and spider webs. I do not know why they eat spider webs. Seems like it would get caught in their teeth.

The gray langur is an adaptable monkey and lives in forests, rainforests, deserts, mountains, and villages. Human villages, I should add. The monkeys don’t make little villages of their own. They even live in large cities, where they will steal food from people and sometimes bite.

For our other monkey mystery, let’s finish up with an unusual monkey that once lived on the island of Jamaica in the Caribbean. Like many island animals, it had no predators and evolved many unique traits. Also like many island animals, it went extinct after humans moved in. The Jamaican monkey, Xenothrix mcgregori, probably only went extinct around 500 years ago, and it was pretty weird-looking. We mostly only know anything about it because of remains found in caves.

The Jamaican monkey had a long tail but short legs compared to most other monkeys. It had leg bones that look more like the legs of a rodent than a monkey. It did live in trees like most monkeys do and probably ate fruit, nuts, and other plant materials. But it didn’t have very many teeth and it moved slowly, which is not a typical monkey trait. It was about the size of the capuchin monkey, up to 22 inches long, or 56 cm.

Scientists had no idea what kind of primate it was until a team managed to extract DNA from some bones. Results of the genetic study were published in 2018 and reveal that the Jamaican monkey was most closely related to the titi monkey.

The titi monkey lives in South America and spends almost all of its time in trees. Its fur is long and soft, and depending on the species it can be brown, gray or black, or even reddish, sometimes with white markings. Unlike the other long-tailed monkeys we’ve talked about today, its tail is not prehensile.

The titi lives in family groups, basically just parents and their children, and pairs mate for life. This is pretty unusual among monkeys. The female usually only has one baby a year and the male cares for it most of the time. If something happens to the parents, sometimes another pair of monkeys will adopt the baby.

This is what the titi monkey sounds like, specifically the black-fronted titi monkey. There’s a link in the show notes if you want to watch the whole video, which goes on for a full minute and is hilarious and adorable.

[monkey sounds]

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