Episode 086: Ammonoids and Nautiloids

Is it extinct? Is it alive? What is the difference between the ammonite and the nautilus? Did Kate get the two confused her whole life until a few months ago and thought they were both extinct? Maybe.

A fossilized ammonite shell:

Another fossilized ammonite shell of a different shape:

A third fossilized ammonite shell of a yet different shape:

A gigantic fossilized ammonite shell:

A fossilized ammonite shell of gem quality, called an ammolite:

This is what an ammonite might have looked like when it was alive. I drew this myself IN MS PAINT because I couldn’t find anything online I liked. There’s 15 minutes of my life I won’t get back:

This is an alive and not extinct nautilus:

Another alive and not extinct nautilus:

The slimy or crusty nautilus. Look, I don’t make these names up:

A nautilus tucked up in its shell and peeking out to see if that diver is going to eat it:

You can contribute to helping conserve the nautilus:

Save the Nautilus

Show transcript:

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

This week let’s learn about two groups of mollusks, ammonoids and nautiloids. One group is extinct, one is still around…but they both look a lot alike, and they’re way more interesting than the word mollusk makes them sound!

We’ll start with ammonoids, specifically ammonites. Ammonites first appear in the fossil record around 409 million years ago, but they died out at the same time as the dinosaurs, around 66 million years ago. Many ammonite fossils look like snail shells, but the shell contains sections inside called chambers. The largest chamber, at the end of the shell, was for the ammonite’s body, except for a thin tube that extended through the smaller inner chambers, which allowed the animal to pump water or air into and out of the chambers in order to make itself more or less buoyant in the water. Some ammonites lived at the bottom of the ocean in shallow water, but many swam or floated throughout the ocean.

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

We have a lot of ammonite fossils, and many of them are beautifully preserved. Some still show a mother-of-pearl layer, a lustrous, iridescent layer of shell that modern molluscs still form. Some ammonite fossils are so lustrous that they’re considered gems, called ammolites. Ammolites are usually polished and made into jewelry. In the olden days people thought ammonites were petrified snakes, and would sometimes even carve the end of the ammonite shell into a snake’s head.

Many fossil ammonites aren’t fossils of the actual shell. When an ammonite died, its empty shell would fill with sediment. Frequently the shell itself wasn’t preserved, but the sediment inside was. That gives us elaborate casts of the insides of ammonite shells, in such good condition that researchers can determine the internal anatomy of the shell. We know mosasaurs frequently ate ammonites because we have fossils with tooth marks that match mosasaur teeth.

There are so many ammonite fossils that paleontologists can date layers of rock by examining which species of ammonite appear in it, called index fossils. Different species frequently had much different shells, some smooth, some with spines or ridges, with tight coils or open coils. Some didn’t coil at all, and instead were straight or had only one or two bends.

But despite all these thousands upon thousands of ammonite fossils, we still don’t know what the animal’s soft parts looked like. Hardly any impressions of ammonite bodies are preserved, only the shells. But ammonites are related to cephalopods like squid, so researchers believe they probably had tentacles.

Nautiloids are also cephalopods. They’re related to ammonites but not closely, about as closely as they’re related to squid. And nautiloids are still alive.

I only found that out recently. A few months ago I came across a picture of a man holding a big snail-like shell with eyes and a bunch of small tentacle things sticking out of the end. I thought it was photoshopped, because I knew those things were extinct! Then I realized that I’ve had nautilus and ammonite mixed up my whole life, and thought they were both extinct and basically the same animal.

They do look a lot alike. Nautilus shells are smooth and rounded like a snail shell, and like the ammonite, nautilus shells also contain chambers filled with gas that keeps the animal from sinking. The nautilus’s body is in the last chamber and extends outside of the shell, with a pair of simple eyes, a beak-like mouth, and as many as 90 small tentacles around the mouth. The top of the shell is striped with brown, while the bottom is white.

Nautilus tentacles are retractable and don’t have suckers the way other cephalopod tentacles do. They do have ridges and secrete sticky mucus that helps them keep hold of their prey. The nautilus also has tentacles around its eyes that are different from its mouth tentacles, and researchers think they act as sensory organs, detecting scent trails in the water. When a nautilus wants to rest, it holds onto a rock with its mouth tentacles so it won’t drift away.

Like squid, the nautilus has a tongue-like structure called a radula, which is studded with exactly nine teeth that it uses to cut up pieces of its prey, mostly crustaceans. It also eats carrion. Like other cephalopods, the nautilus has blue blood instead of red since it contains hemocyanin instead of hemoglobin. Also like squid and other cephalopods, the nautilus has a siphon, properly called a hyponome. In the nautilus, the hyponome is a flap that’s folded over to form a tube, instead of an actual tube in squid and octopus. The animal sucks in and expels water through the hyponome, which propels it through the ocean. If it’s threatened, the nautilus can actually withdraw all the way into its shell like a snail, covering the entrance with two large, folded tentacles.

The first fossil nautiloids are found in rocks dating to the Cambrian period, some 500 million years ago. Earlier nautiloids are sometimes straight, sometimes slightly curved, and sometimes coiled like ammonite shells. Even so, overall the nautilus hasn’t changed much since the Cambrian. Like the ammonite, some species of nautiloid once reached over 8 feet across, or 2.5 meters.

Today there are only six species of nautilus left, and they’re endangered due to habitat loss, pollution, and poaching. The shells of larger individuals can be worth a few hundred dollars to collectors, and while selling the shells is illegal in many countries, as long as there are unscrupulous or just clueless people who buy the shells, poaching of nautiloids will continue to be a problem. A good rule is that if you’re a tourist and someone is selling any kind of animal part, don’t buy it. Even if you think it’s harmless, you might be contributing to the extinction of an animal—plus, it’s probably going to get confiscated by customs anyway.

The problem is that the nautilus matures very slowly. It lives to be over 20 years old, but it isn’t mature until it’s about 15 years old. Its eggs take a long time to hatch too. So the nautilus is slow to recover from overhunting, which makes it vulnerable to extinction.

One species of nautilus is so rare it’s only been seen a few times, and hadn’t been seen in more than 30 years until one was spotted in 2015 off the coast of Papua New Guinea. It’s called Allonautilus scrobiculatus, and unlike other nautilus species, its shell is covered with a thick coating of hairy slime that gives it its popular name, the slimy nautilus or crusty nautilus. It grows to about 8 inches across, or 20 cm. Its close relative Allonautilus perforates is even rarer. In fact, it’s never been seen alive, and researchers don’t know much about it since all they have to study are empty shells found drifting in the water. It grows to about 7 inches across, or 18 cm.

Most living nautiloids are about that size, but the biggest is a subspecies of the chambered nautilus, often called the emperor nautilus. Before you get too excited, though, the biggest ones only grow to about ten inches across, or 25 cm.

Nautiloids don’t like water that’s too warm so they usually live near the bottom of the ocean, although their shells can’t withstand the pressures of abyssal depths. If a nautilus descends too far, its shell implodes and it dies instantly, like a hapless diver in a malfunctioning bathysphere. Nautiloids live in the Indo-Pacific Ocean and like the deeper parts of coral reefs.

So why did ammonites die out during the Cretaceous-Paleogene extinction event while nautiloids didn’t? Researchers think ammonites laid eggs that floated near the top of the ocean, while nautiloids lay eggs that stay on the bottom of the ocean. Specifically, female nautiloids attach their eggs to rocks in warm water, which take up to a year to hatch. Eggs at the bottom of the ocean were protected from most of the effects of the meteor impact, while those near the surface were killed.

Is it possible that some ammonites survived and still live in the deep sea, unknown to humans? I’m going to say probably not. Ammonites shared a lot of physical similarities with nautiloids, so they probably weren’t able to live in the deep sea without imploding. While it would be amazing if scientists discovered a living ammonite, we should celebrate that the humble nautilus is definitely still alive. It’s still blowing my mind, to be honest.

If you’d like to help nautilus conservation efforts, you can visit save the nautilus.com for more information. I’ll put a link in the show notes.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. 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 whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 085: Crocs, Gators, and Their Massive Terrifying Cousins

This week’s episode is all about crocodiles, alligators, and their relations. Thanks to Damian, John Paul, and John Paul’s son for the recommendation!

A Chinese alligator:

It’s easy to tell alligators and crocodiles apart. Just ask them to stand side by side, then lean over and look down to see the head shape. Broad-headed alligator on left, slender-headed crocodile on right:

Saltwater crocodile. Look, I’m only going to say this once: DO NOT SIT ON A CROCODILE OKAY THAT IS JUST DUMB AND YOU WILL GET EATEN ONE DAY IF YOU KEEP ON DOING IT

A gavial:

Black caiman:

Further reading:

A newly discovered difference between alligators and crocodiles

Show transcript:

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

This week’s episode is about crocodiles and alligators, and their relations. Thanks to a couple of different listeners for the suggestion, Damian and John Paul, and John Paul’s son. We’ve touched on crocodiles before in a couple of different episodes, including episode 53 about dragons, but alligators have barely had a mention.

Crocs and gators aren’t actually that closely related, but both are members of the order Crocodilia. This order also includes caimans and gavials, as well as some verrry interesting extinct members.

Crocodilians are amphibious reptiles. They spend much of their time in the water but also spend time on land. They breathe air, lay eggs, and depend on air or water temperature to regulate their body temperature. All crocodilians have evolved to take advantage of their watery habitat: long tails that are flattened laterally, eyes and nostrils close to the top of the head, short legs with webbed toes, and a flap at the back of the mouth that keeps water from flowing into the throat and airways. They can stay underwater for at least 15 minutes without needing to surface for air, and some individuals can stay underwater for close to two hours under the right conditions.

Crocodilians have thick protective scales on much of the body, called scutes, strengthened by osteoderms, or bony plates. Some scutes contain sensory receptors that sense touch, heat and cold, chemical stimuli, and especially the movement of water. Crocodilians see well even in darkness and have good hearing and smell too.

Some mother crocodilians lay her eggs in holes in the sand, but most build a nest out of vegetation. As the vegetation rots, it generates heat that warms the eggs. If the temperature in the nest is constantly above 90 degrees Fahrenheit, or 32 Celsius, more babies develop into males. If the temperature is cooler than that overall, more babies develop into females.

The mother protects the nest, which is usually near her den. Sometimes several females nest close to each other to help each other protect the nests. When her babies start hatching, the mother crocodilian digs them out of the nest since they aren’t strong enough to do it themselves, and carries the babies to water where they are safer. She also protects them for a while after they hatch. This is important, because baby crocodilians are vulnerable to predators—including adults of their own species.

Different species of crocodilians communicate in different ways. Some roar or bellow, some hiss, grunt, slap the jaws shut loudly, splash the head or tail in the water, or blow bubbles. Males often growl infrasonically—a sound humans feel more than hear, and which can cause the water around the male to shiver. That’s creepy. Baby crocodilians still in the egg will mimic tapping sounds, and yelp or grunt to let their mother know when they’re hatching.

One interesting thing about crocodilians is the way they walk. Most of the time a crocodilian walks with its belly touching the ground and its tail dragging. This is called the low walk. But unlike most other reptiles, most crocodilian species have ankle joints that allow it to raise its body up off the ground and walk like a mammal, with only the end of the tail dragging. This is called the high walk. Some smaller species can even run, a bounding gait something like a rabbit’s. Crocodilians can also jump.

If you’ve ever heard the phrase “crocodile tears,” which refers to someone who pretends to feel bad while doing something mean, it comes from the belief that crocodiles wept while eating their prey. The belief goes back at least 900 years and probably longer, and it’s actually based on a real phenomenon. When a crocodilian is in the water, its eyes are protected by both a see-through third eyelid, properly called a nictitating membrane, and by a tear-like lubricant that washes any grit out of the eye. The lubricant is visible when the animal is out of the water, and it looks like the crocodile is crying.

Many crocodilians are ambush hunters. They lie mostly submerged, only their eyes and nostrils above the surface of the water, and wait for an animal to approach. Then they grab the animal with their powerful jaws and drag it into the water to drown. This requires massive bite strength, and crocodilians have the strongest bite of any animal alive. Recently, 3D modeling of an alligator’s head revealed a second jaw joint that stabilizes the jaw and helps distribute the bite force throughout the skull.

In case you were wondering how to tell a crocodile from an alligator, crocodile snouts are more slender than alligator snouts. It’s easy to tell the two apart when their mouths are closed, since only the upper teeth are visible when an alligator closes its mouth, while a crocodile shows both upper and lower teeth.

Besides, there are only two species of alligator alive today, the American alligator that lives in the southern United States, and the Chinese alligator, which lives in eastern China. The Chinese alligator is the smaller species, no more than 7 feet long, or 2.1 meters. While most crocodilians have soft bellies, the Chinese alligator has an armored belly. It lives in marshes, lakes, and rivers but these days it’s critically endangered and mostly restricted to the Anhui Chinese Alligator Nature Reserve. In 1999, conservationists estimated that there were only about 150 Chinese gators alive in the wild. Fortunately, since then more protected habitats have been developed for the gators and captive breeding programs have released many young gators into the wild. Their numbers in the wild are increasing slowly, but since the gators also do well in captivity, it’s estimated that as many as 10,000 individuals live in zoos around the world.

As for the American alligator, back in 1967 it was listed as endangered, mostly due to hunting and the sale of baby alligators as pets. Alligators do not make good pets, which you could probably figure out just by thinking about how big gators get. That would be more than 15 feet long for a big male, or 4.6 meters. Fortunately, conservation made a huge difference to the American alligator and it’s now considered fully recovered from its low point in the 1960s.

The American alligator lives in wetlands throughout the deep southern states, including parts of Texas, across to Florida and up through parts of North Carolina. It eats pretty much anything it can catch, including fish, crabs and other crustaceans, birds, mammals, frogs and other amphibians, and reptiles like turtles and snakes. It also sometimes eats fruit. Because the alligator can tolerate a certain amount of salt water, and frequently lives near the ocean, occasionally one will eat a shark. But sharks sometimes eat alligators too. Alligators also help control the spread of exotic species released in the Florida Everglades and other areas, including Burmese pythons. Full-grown alligators frequently hunt on land, but young alligators mostly stay in the water. Young American alligators have thin yellowish stripes that fade as the gator grows.

There’s another crocodilian with a range that overlaps with that of the American alligator, the American crocodile. It’s usually paler in color than the alligator with a relatively narrow snout. It mostly lives in central America, but some do live in southern Florida, which makes southern Florida the only place in the world where gators and crocs live side by side in the wild. But crocodiles can’t tolerate cool weather as well as alligators, so cold snaps in Florida can kill off crocodiles while not harming alligators. Occasionally a big alligator will eat a smaller crocodile, but on average the croc is the bigger animal. Big males can occasionally grow over 20 feet long, or 6.1 meters. It frequently lives in salt water where it mostly eats fish and birds, along with small mammals, reptiles, amphibians, and crustaceans. It especially likes to eat lemon sharks. I mean, who wouldn’t, right? They sound delicious. Or maybe I just like lemons.

Unlike the American alligator, the American crocodile is endangered due to habitat loss, poaching, and pollution. It’s more dangerous to humans than the alligator, but not nearly as dangerous as some other species of crocodile.

The saltwater crocodile and the Nile crocodile are the most dangerous species to humans. The Nile crocodile can grow over 21 feet long, or almost 6.5 meters, and lives throughout much of Africa. The saltwater crocodile is the biggest crocodilian alive, and can grow up to 23 feet long, or 7 meters.

Like the American crocodile, the saltwater crocodile can tolerate salt water and frequently lives in coastal areas like the mouths of rivers, lagoons, and mangrove swamps. It’s found in parts of India down to northern Australia, and occasionally one will swim across the ocean to areas far from its usual range, including Japan and Fiji. Saltwater crocodiles, especially males, are territorial, and researchers think that about half of attacks on humans result from the human straying into a croc’s territory. These attacks aren’t usually fatal, but I bet they’re scary.

There are other crocodilians besides just the alligator and the crocodile. The gavial, also called the gharial or fish-eating crocodile, has a long, narrow snout that helps it catch the fish it eats. It lives in parts of India these days, in a few rivers and along the coasts, since it can tolerate salt water. It used to live throughout India and other parts of Asia, but it’s been hunted almost to extinction. In 1976 conservationists estimated that there were fewer than 200 gavials alive in the wild. Even after India put protections in place for the gavial, it continued to decline. In 2006 there were only 182 adult gavials alive. Conservationists are working hard to increase the population, including breeding them in captivity and releasing the babies into protected wildlife preserves in the wild. The main problems these days are loss of habitat and pollution, everything from dams across the rivers where it lives, heavy metal poisoning from polluted water, and drowning after entanglement in fishing nets. But population numbers have grown thanks to the conservation efforts, although there are probably fewer than 1,000 in the wild today.

The gavial can grow as long as the saltwater crocodile, although it’s usually much less heavy, with the longest measured at 23 feet long, or 7 meters. Adult males have a bulb at the end of their snouts that researchers think help them blow bubbles and make hissing and buzzing sounds that attract females.

Baby gavials eat tadpoles, frogs, and small fish. Adults eat fish and crustaceans. The gavial’s jaws are too delicate for it to feed on larger prey. In the past, hunters found jewelry in gavial stomachs and assumed they were maneaters, but it’s more likely they just swallowed jewelry lost in the river because it was shiny like fish scales.

There’s also a false gharial, which looks superficially like a gavial but has a broader snout. It’s reddish-brown with black splotches and some striping on the back and tail. These days it only lives in swamps in Indonesia and some nearby areas, although it used to have a broader range and also lived in rivers and lakes. Like the gavial, it’s been hunted to extinction in much of its former range for its skin and meat, and because people are afraid of it. It’s also vulnerable to habitat loss, including water pollution and draining of wetlands. It eats fish and other water animals, but it also preys on birds and mammals, and can grow more than 13 feet long, or 4 meters.

Caimans are most closely related to alligators and live in Central and South America. Some species are relatively small, from the 5 foot long, or 1.5 meter, Cuvier’s dwarf caiman, to the black caiman that can grow over 16 feet long, or 5 meters. Some researchers think the black caiman may occasionally grow up to 20 feet long, or 6 meters. Caiman scales are stiffened by calcium deposits, which makes caiman hide less valuable to leatherworkers than other crocodilian hides because it’s less pliable.

All crocodilians share an ancestor that lived around 240 million years ago. That same ancestor was also the ancestor of the dinosaurs. So it’s no surprise that crocodilians are considered the closest living bird relatives.

Paleontologists have discovered many extinct crocodilians, some of which look really strange. Mourasuchus, for instance, was a type of caiman that lived in South America during the Miocene, around 13 million years ago. Mourasuchus had long, flat jaws that looked something like a duck’s bill full of tiny conical teeth. Researchers think it may have been a filter feeder, filtering small animals from the mud at lake bottoms. But it was enormously big, some 39 feet long, or 12 meters.

Another possible filter feeding crocodilian was Stomatosuchus, which lived in Northern Africa around 95 million years ago and grew to 33 feet long, or 10 meters. It had a long, flat snout with small conical teeth in the upper jaw and may have had no teeth in the lower jaw. Some researchers think it might have had a pouched lower jaw like a pelican, which it used to catch small fish. It would suck in water, filling its pouch, then close its jaws and push the water out through its teeth. Any fish or other animals left in its mouth when all the water was expelled, it swallowed. But we don’t know for sure because only one Stomatosuchus skull has ever been found, and it was destroyed in 1944 when the museum it was in was bombed during World War II.

Purussaurus was another extinct caiman that lived in South America around 5 to 20 million years ago, and is estimated to grow as much as 41 feet long, or 12.5 meters. We don’t know its length for sure since we don’t have a complete skeleton, but if estimates are right, it was one of the biggest crocodilians that ever lived. It had a strong skull and huge teeth that allowed it to hold onto large prey.

Sarcosuchus was about the same size as Purussaurus, around 40 feet long, or 12 meters, but lived about 112 million years ago in what is now Africa and South America. It ate dinosaurs.

The largest living crocodilian ever reliably measured was a captive saltwater crocodile from the Philippines. He was captured in 2011 after rumors started that he had killed at least two people. He was kept on display in a wildlife center, and caretakers named him Lolong after one of the men who helped capture him. Lolong the crocodile was measured at 20 feet 3 inches long, or 6.17 meters, and he weighed 2,370 lbs, or 1,075 kg.

But crocodilians even larger than Lolong have been measured, just not by wildlife experts. Another saltwater crocodile in India has been estimated at 23 feet, or 7 meters, and a saltwater croc skull from Cambodia suggests that the living animal might also have been 23 feet long. A crocodile killed in Queensland, Australia in 1958 was supposedly 28 feet 4 inches long, or 8.64 meters, but this is probably an exaggeration.

But size is relative. A crocodilian that lived in South America some 60 million years ago and grew to a respectable 18 feet long, or 5.5 meters, probably got eaten by the largest known snake that ever lived, titanoboa. Titanoboa grew up to 42 feet long, or 12.8 meters. But that is a story for another day.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. 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 whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 084: Gorillas

This week let’s learn about a close relative, the gorilla!

But first, if you don’t already listen to these fantastic animal podcasts, definitely check them out!

Species   All Creatures   Life Death & Taxonomy   Animals to the Max   Varmints   Cool Facts about Animals

Why hello there:

This gorilla has some lettuce. It looks pretty good:

Some mountain gorillas with awesome hair:

GORILLA BABY FLOOFY HEAD ALERT:

Show transcript:

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

This week we’re going to learn about gorillas, mostly because I just found out they sometimes hum happily while they eat. And yes, I have audio of happy munching gorillas that will make you want to snack too.

But first, did you notice what happened last week? If you subscribe to several animal podcasts, you might have noticed that the first week of September 2018 suddenly turned into big cat week! A bunch of us animal podcasters thought it would be hilarious to release episodes covering the same topic in the same week.

Species covered snow leopards, All Creatures covered lions, Life Death & Taxonomy covered jaguars, Animals to the Max covered wildcats, Varmints covered tigers, Cool Facts about Animals covered mountain lions, and of course we had our mystery big cats episode. I’ll put links in the show notes to each podcast, but I recommend all of them. One thing I love is that all these podcasts can cover the same topic but approach it so differently that you’ll never get bored and think, Oh, I already know about this animal.

Anyway, let’s learn about gorillas!

The gorilla is a great ape, closely related to chimpanzees, bonobos, humans, orangutans, and gibbons. There are two species, the eastern and the western, separated by the Congo River, and several subspecies. All gorillas live in Africa, but different species and subspecies live in different environments. Eastern gorillas prefer forests, including bamboo forests, but the mountain gorilla subspecies lives at a much higher elevation. Western gorillas live in swampy forests too. The western gorilla’s scientific name is Gorilla gorilla, and the scientific name of the western lowland gorilla subspecies is Gorilla gorilla gorilla. Don’t say you never learned anything from a podcast.

The gorilla is the largest primate alive today. They usually knuckle-walk, but can walk upright for short distances when they want to, usually when carrying something. Gorillas are vegetarian, although they will also eat insects. They have brown eyes and unique fingerprints like humans have. They also have black, brown, or grayish hair, and the western lowland gorilla also has a reddish forehead. Mountain gorillas have longer hair than lowland gorillas. They look awesome. Male gorillas develop silver hair on the back as they mature, which is why they’re usually called silverbacks. A silverback male acts as the leader of his group, making decisions and stopping other gorillas from arguing with each other. The silverback also plays with the children in his troop, even if they aren’t his offspring. If the group is attacked, the silverback will defend his troop to the death—in addition to his silver fur, silverbacks develop large canine teeth that can inflict massive wounds. But the gorilla is so big and strong, it doesn’t have many predators. Leopards will occasionally kill a gorilla if they catch one alone, but generally the only danger to gorillas comes from humans.

The gorilla is vulnerable to habitat loss, poaching, and human disease. More than 5,000 gorillas may have died due to the ebola virus outbreak in the 2000s, and gorillas can also suffer from malaria. But things are looking up for the gorilla, at least a little bit. The population of critically endangered mountain gorillas in the Virunga Volcanoes has doubled in only 25 years, finally climbing over 1,000 individuals, following some intensive conservation efforts.

In the 1990s, researchers estimated that there were only 50,000 western lowland gorillas alive. Then a survey of gorilla populations in the Republic of the Congo made an amazing discovery. In 2007, researchers discovered that there was an entire population of gorillas in the swamps and forests that they had never even known about—and not just a few gorillas, either. Estimates put the population at about 125,000. That doesn’t mean there’s nothing to worry about, of course. Gorillas are still endangered, but at least there are more of the western lowland gorilla than we thought.

The gorilla spends most of its time on the ground. Young gorillas will climb trees, but adults are usually too big and heavy and feel more comfortable on the ground unless they’re actually after a specific food. Just like humans—and in fact, a recent study found that the heel bones of our ancestor Australopithecus had more similarities with gorilla heel bones than with chimpanzee heel bones, even though humans and our ancestors are more closely related to chimps. The study gives researchers a better idea of how our ancestors got around.

At night, each gorilla builds a nest to sleep in from branches and leaves. These are on the ground, and since gorilla troops travel sometimes several miles every day to find food, they usually build a new nest every night. Sometimes they’ll build a nest to nap in during the day too. Babies nest with their mothers, but when a young gorilla is around three years old, it will start building its own nest near hers.

As young gorillas grow up, they usually move away from their home troop and join other troops, or in the case of males, they eventually start their own troops. The female chooses her mate, and usually has one baby every four years or so. Baby gorillas are even smaller than human babies, only about four pounds, or 1.8 kilograms. Babies cling to the mother’s fur and ride on her back when she’s walking.

Gorillas eat lots of different types of plant, especially fruit, tree bark, various roots and leaves, and the stems of some plants. An adult gorilla eats around 40 pounds of food a day, or 18 kg. And gorillas frequently sing and hum while eating, especially when a gorilla is eating a food it particularly enjoys. Researchers think that the singing is partly communication with others—sort of a dinner-time conversation—partly just to show their happiness with having food they like. This is what gorillas sound like while eating and humming. I don’t know about you, but this sounds totally appetizing. It sounds like they’re eating popcorn, but in fact it’s the leaves of the banana tree.

[gorillas eating and humming]

Like all great apes, gorillas are highly intelligent. They use tools, laugh, grieve their dead, have a complex system of communication, and even prepare food in ways that varies from region to region. A few captive gorillas have been taught to speak using a form of sign language, most famously Koko.

Koko was an amazing ape. She only died earlier this year, 2018, at the age of 46. She was a western lowland gorilla born in the San Francisco Zoo, and her proper name was Hanabiko, which means ‘fireworks child’ because she was born on the Fourth of July. She spent much of her life in a gorilla preserve in Woodside, California, and was purposefully exposed to spoken English from about age one. By the time she died, she could understand more than 2,000 words in English and knew over 1,000 signs.

Different studies of Koko and her use of language come to different conclusions. Some researchers claim she didn’t demonstrate any kind of grammar, while others claim her language use was extremely human. But everyone except utter curmudgeons agrees that Koko was actually using language to communicate. She even made up some signs when she needed a new word.

Koko also demonstrated a sense of humor, encouraged other gorillas when they attempted to sign, talked about her memories, recognized herself as the individual in a mirror, and even gave her pet kitten a name without being prompted. His name was All Ball, and when he later escaped her enclosure and was killed by a car, she cried. She had other pet cats later, all named by her, including Lipstick, Smoky, Miss Black, and Miss Grey. I’m just saying, Lipstick is a great name for a cat. Koko was reportedly gentle with her pets and when they were kittens, she treated them like baby gorillas.

Young gorillas play games like all young mammals do. Tag, for instance. Young gorillas, and sometimes even older ones, play tag. Researchers say that according to their observations, it appears that the rules of gorilla tag are pretty much the same as the human version of tag. Researchers do not report whether or not there was a big argument about who hit whom when they supposedly called a time-out to tie their shoe, probably because gorillas don’t wear shoes.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. 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 whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 083: Lions, tigers, and other big cats…of mystery!

I’ve been meaning to do a big cat episode for a while, thanks to listener Damian who suggested lions and tigers! But when I started my research, I immediately got distracted by all the reports of mysterious big cats. So here’s another mysteries episode!

Here are the links to some Patreon episodes that I’ve unlocked for anyone to listen to. Just click on the link and a page will open, and you can listen on the page. No need to log in.

Marsupial lions

Blue tigers and black lions

The Queensland tiger, which is not actually about any kind of actual tiger

A lion and cub. This picture made me die:

The Barbary lion, possibly extinct, possibly not:

Watch out! Tigers!

A king leopard with stripe-like markings instead of spots:

Further reading:

Hybrid and Mutant big cats

Peruvian mystery jaguar skulls studied

Show transcript:

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

This week we’re going to learn about some mystery big cats. We’ve touched on big cats before in various episodes, including the British Big Cats phenomenon in episode 52. We’re definitely going to see some more out of place animals this week, along with lots of information about big cats of various kinds. Thanks to Damian who requested an episode about lions and tigers ages ago.

I’ve also unlocked three Patreon episodes so that anyone can listen to them. They won’t show up in your feed, but there are links in the show notes and you can click through and listen on your browser without needing a patreon login. The first is about marsupial lions and the second is about blue tigers and other big cats with anomalous coat colors. The sound quality on the blue tigers episode is not that great, but it’s a long episode with lots of information about blue tigers, white tigers, black tigers, white lions, king cheetahs, and lots more. The third is about the Queensland tiger, an Australian animal that’s not a feline of any kind, but why not?

The term big cat refers to tigers, lions, leopards, snow leopards, and jaguars, but it can also include cheetahs and cougars depending on who you ask. Big cats have round pupils instead of slit pupils like domestic cats and other smaller cats.

Lions, tigers, leopards, and jaguars can all roar. Snow leopards, cheetahs, and cougars can’t. But snow leopards, cheetahs, and cougars can purr, while lions, tigers, leopards, and jaguars can’t. The ability to roar is due to special adaptations in the larynx, but these adaptations also mean big cats can’t purr. So basically a cat can either roar or purr but not both.

The word panther, incidentally, refers to any big cat and not to a specific type of animal. So a black panther, in addition to being an awesome movie, is any kind of big cat exhibiting melanism, which causes the animal’s fur to be black all over. Leopards and jaguars are most commonly referred to as black panthers. Lions, tigers, and cheetahs do not exhibit true melanism as far as researchers have found.

Let’s start with lions. Lions live only in Africa these days, but were once common throughout parts of southern Asia too and possibly even parts of southern Europe. The lion is most closely related to the leopard and jaguar, less closely related to the tiger and snow leopard, but it’s so closely related to all those big cats that it can interbreed with them in rare cases.

There are two species of lion, the African and the Asian. Until recently there were also several subspecies of African lions, including the American lion, which once lived throughout North and South America. It only went extinct around 11,000 years ago. The American lion is the largest subspecies of lion ever known, about a quarter larger than modern African lions. It probably stood almost four feet tall at the shoulder, or 1.2 meters. Cave paintings and pieces of skin preserved in caves indicate that its coat was reddish instead of golden. It lived in open grasslands like modern lions and even in cold areas. There are reports of a reddish, short-maned cat supposedly called a “jungle lion” sighted in South America, but I can’t find much information about it and it’s much more likely to be a jaguar or cougar than a relic population of American lions. But wouldn’t that be awesome if it was.

The Barbary lion was a subspecies of African lion that lived in northern Africa until it was hunted to extinction. The Barbary lion was the one that battled gladiators in ancient Rome and was hunted by pharaohs in ancient Egypt, a big lion with a dark mane. The last one was supposedly killed in 1922, but recent research indicates that they survived much longer—maybe as late as 1958 or later. The last recorded sighting was in 1956, but the forest where it was seen was destroyed two years later.

One zoo in Morocco claims that their lions are purebred Barbary lions, descended from royal lions kept in captivity for centuries. But since we don’t have a full genetic profile of the Barbary lion to start with, it’s hard to determine whether the royal lions are Barbary lions. So far a 2005 DNA test on five of the royal lions indicates they probably aren’t, but DNA testing has come a long way since then and new tests on the royal lions and on preserved Barbary lion skins will hopefully be done soon.

The Sumatran golden lion, also called the cigau [pronounced chee-gow] is a mystery lion that is supposed to be golden in color with no markings, a relatively short tail, and with a mane or ruff of fur that’s sometimes described as white. It’s only about the size of a small donkey or large goat, but stocky like a lion. The most recent sightings are from the 1960s, where one supposedly attacked and killed a man. Some researchers think it may be a subspecies of the nearly extinct Asiatic lion, but others say it’s more likely to be an animal of folklore. Then again, there are tigers on Sumatra and it’s always possible it’s an anomalous coated tiger with no stripes, or stripes that are almost the same color as its coat. Tigers do have a white ruff around the face.

Lions are well known to live on the savanna despite the term king of the jungle, but they do occasionally live in open forests and sometimes in actual jungles. In 2012 a lioness was spotted in a protected rainforest in Ethiopia, and locals say the lions pass through the reserve every year during the dry season. That rainforest is also one of the few places left in the world where wild coffee plants grow. So, you know, extra reason to keep it as safe as possible.

Let’s talk about tigers next. Tigers are awesome animals, with the Bengal tiger being the biggest big cat alive today—on average even bigger than the lion. Tigers are good swimmers and most really like the water, unlike most cats. They live throughout Asia but once were much more common and widespread. I’ve found a lot of mystery tiger reports, but if you’re interested in tigers of unusual colors, I really do recommend you go listen to the unlocked Patreon episode about blue tigers.

The so-called beast of Neamt is a modern mystery from Romania. In spring of 2016, farmers started finding livestock killed during the night, but not eaten. The predator was clearly extremely strong, much stronger and larger than a dog. Its method of killing didn’t suggest a bear, which locals were familiar with anyway.

Some of the sightings seem normal, of a catlike animal the size of a calf. Other sightings were more bizarre. Some people reporting seeing a huge animal running on two legs, one guy said he’d wounded it with an axe but it didn’t bleed, and of course there were the predictable reports that animals it killed were drained of blood.

But in this case, DNA testing solved the mystery of what was killing the animals. The beast was injured by a barbed-wire fence, and a test of its blood indicated it was a Siberian tiger. The Siberian tiger is also called the Amur tiger, which we talked about in episode 44, Extinct and Back from the Brink. But there are probably no more than 500 Siberian tigers alive in the wild, and none of them live within 3,000 miles of Romania, or 5,000 km. So while we know what the beast of Neamt is, we don’t know how it got there. Out of place tigers, hurrah!

Another mystery tiger is from Chad in Africa. This one is sometimes called the mountain tiger, and it’s supposed to be the size of a lion but with reddish fur, white stripes, no tail, and huge fangs.

This doesn’t sound like anything alive today—but it does sound like an extinct cat called Machairodus. It was the size of a lion, or over 3 feet tall at the shoulder, or 1 meter, and around 6 ½ feet long, or 2 meters. It was a type of saber-toothed cat like Smilodon, although it wasn’t closely related to Smilodon and its fangs weren’t as big. It probably had a short tail. But Machairodus and its relatives died out probably a million years ago, although it might have persisted to only 130,000 years ago. That’s still a lot of years, so it’s not too likely that a population of its descendants still lives in Chad. For one thing, northern Chad is part of the Sahara, while southern Chad is a savanna. It’s not dense jungle or remote mountains.

But there are similar reports of the mountain tiger in other parts of Africa, where there are steep mountain ranges that aren’t well explored. And, oddly enough, similar reports also come from South America and even from Mexico. Machairodus did live in Africa, Eurasia, and North America, although its fossils haven’t been found in South America. Maybe the reports aren’t of a living animal but were inspired by fossil remains. Hunters who stumbled across fossil machairodus bones would recognize them as similar to tiger or lion skeletons, but wouldn’t know that the living animal was long gone.

Another South American big cat report comes from Ecuador. It’s called the rainbow tiger or rainbow jaguar, and it sounds really pretty. In the Macas region in southeastern Ecuador, in the Amazon jungle, locals have a story about a big cat properly called Tshenkutshen. The cat is the size of a jaguar, or up to six feet long not counting the tail, or 1.85 meters, but instead of having a pattern of dark rosettes on a tawny background coat, the rainbow tiger is black with stripes on its chest. The stripes are different colors: white, red, yellow, and black, which gives it the rainbow name. One report I saw says it’s white with black spots in addition to the stripes on its chest. It lives in the trees in remote areas, is rare, and at least one report says it has a hump on its shoulders and monkey-like forepaws but with claws. One was supposedly shot and killed in 1959, but there are no pictures of the carcass and no one knows where it went, if it even existed in the first place.

Naturally, the rainbow tiger isn’t actually a tiger since tigers don’t live in South America. If it is a real animal and not a folktale, it’s probably a type of jaguar. But the whole monkey hands thing implies it’s probably more of a mythological creature than a flesh and blood one, because no feline of any kind has forepaws that resemble hands.

There’s an interesting addition to the rainbow tiger mystery. Dutch primatologist Dr. Marc van Roosmalen spotted a strange jaguar during an expedition through Brazil in the late 1990s. It was mostly black, but had a white pattern around its throat.

There are plenty of other South American big cat mysteries, including the yemish that we covered in episode 59 along with the onza, a mystery cat from Mexico and central America. But one especially interesting report is from Peru. Peter Hocking is a Peruvian ornithologist, or someone who studies birds, but he’s also interested in other animals. In 1996 he got his hands on two skulls that were similar to jaguar skulls but reportedly not from jaguars, but from strange striped big cats instead.

In 2010, zoologist Darren Naish asked for and finally received high-quality plaster replicas of the skulls so he could study them. His conclusion is that both skulls are actually from jaguars, but he points out that most big cat species do occasionally produce anomalously striped individuals. No one knows where the pelts of these two jaguars are, unfortunately. Hopefully they’ll turn up eventually, or another striped jaguar will be found and can be studied so we can learn if it’s just an individual with an anomalous coat pattern, or an actual subspecies of jaguar with stripes instead of spots.

I couldn’t find any mystery cheetah reports beyond one called the Tennessee red cheetah. That excited me because I live in Tennessee and I’d never heard of it before. The Tennessee red cheetah is supposed to resemble the cheetah, golden brown with black spots, but with a reddish dorsal stripe and tail. Some reports say it’s reddish-brown all over with black spots.

That’s it. That’s all the information I can find. I was so disappointed, but basically it sounds like a tall tale or maybe a sighting of a jaguar. That’s the problem with mystery big cat reports. There are so many reports of so many animals that don’t correspond to any known species or subspecies of big cat, with few concrete details. In the case of the Tennessee red cheetah, the only details I could find were vague stories about one being shot and skinned, but the skin was missing. No date, no place, no names, nothing.

You can’t treat a report like that with anything but skepticism, so let’s move on to another mystery big cat, the Zanzibar leopard. When I was making notes for this episode, I wrote “probably extinct, may be too depressing to use.” But there’s always a chance it’s not extinct.

The Zanzibar leopard lives on Zanzibar Island off of Tanzania. It’s not a big island, only around 50 miles long, or 85 km, and 20 miles wide, or 30 km. The Zanzibar leopard was probably separated from the mainland population of leopards when sea levels rose after the last ice age. It’s smaller than a mainland leopard, with smaller spots, but not much is known about it since it hasn’t been studied in the wild and it may be extinct now. Unfortunately, many people on the island believed that the leopards were witches’ familiars, and that they should be killed. In 1964 the islanders overthrew the government, but also unfortunately, the newly installed government persecuted people it decided were witches. This included a government-run campaign to kill all leopards on the island. By the mid-1990s, conservationists suspected the Zanzibar leopard was extinct.

But there is hope. Earlier this year an Animal Planet show caught footage on a camera trap of what appears to be a Zanzibar leopard. Hopefully there are still some of the leopards remaining, and if so, hopefully they can also be protected.

Speaking of Tanzania, let’s finish with a big cat that might very well be a real animal—or something even more mysterious. The nunda is supposed to be a huge gray cat with tabby stripes, reported in Tanzania. Its paw prints are supposed to resemble a leopard’s, but are as big as a lion’s.

In a 1927 article, a British administrator named William Hichens reported about his investigation into nunda attacks around the village of Lindi in Tanzania. The attacks occurred in 1922, and started with a night watchman who was found dead one morning. Clutched in the dead man’s hand was a tuft of gray fur that Hichens thought might have been torn from a lion’s mane. But lions were rare in that part of Tanzania, and two locals reported seeing a huge brindled cat attack the man during the night. A few nights after that, another watchman was also killed in the same way, including the tuft of hair clutched in one hand, and that was followed by more attacks in other villages over the next several weeks. The attacks stopped, but resumed in the 1930s. Some huge footprints and more of the gray fur were found by a British hunter who tried to track the animal.

So what might the nunda be? The description doesn’t sound like any known big cat. Cryptozoologist Bernard Heuvelmans suggested it might be a huge African golden cat with anomalous markings. The African golden cat is related to the caracal and the serval, both fairly small, long-legged cats. It has variable markings and coloring, from reddish to grey, from spotted to nearly plain. But it’s only about twice the size of a domestic cat. Its paws are large for its size, but it’s not anywhere near the size of a leopard, much less a lion.

Of course, it might be a larger subspecies of golden cat, or a totally different species. But there is another possibility, one that’s far creepier and darker than an unknown big cat.

According to a book called Wild Cats of the World by Mel and Fiona Sunquist, published in 2012, in the early 20th century a group of witch doctors in that part of Tanzania ran an extortion racket. They demanded money from people and threatened to turn into lions and kill them if they didn’t pay up. And they did kill people—over 100 of them, according to the book. The murders were committed by young men who dressed like lions, including wearing lion paws on their feet so they left lion paw prints.

That would explain the rash of murders in a localized area, and the fact that so many of the victims were found clutching gray fur. The fur was never tested and could have come from any animal and been planted on the victims.

Zoologist Karl Shuker suggests that if the deaths weren’t due to these lion-men, the mystery big cat might be a type of leopard with stripes instead of spots. Leopards with stripes due to genetic coat anomalies are extremely rare, but they aren’t unheard-of. They’re sometimes referred to as king leopards. I have a picture of one in the show notes. While leopards can cross-breed with tigers, tigers don’t live in Africa, so a striped leopard-tiger hybrid wouldn’t be hanging around in Tanzania, certainly not in the 1920s.

Whatever the cause, no one has reported a nunda sighting in about 80 years.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. 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 whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!