Category Archives: extinct

Episode 044: Extinct and Back from the Brink

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Our episode this week is about some causes of extinction, but to keep from getting too depressing we’ll look at a lot of animals that were brought back from the brink of extinction by people who saw a problem in time to put it right. We’ll learn a lot about the passenger pigeon this week especially. Thanks to both Maureen and Emily for their suggestions! I didn’t mean to lean so heavily on North American animals in this episode–it just happened that way. I try to mix it up a little more than this ordinarily.

The passenger pigeon (stuffed):

The tiny black robin. It fights crime!

The Tecopa Pupfish is not happy about being extinct:

The West Virginia Northern Flying Squirrel SO CUTE:

This is what the Golden Lion Tamarin thinks about habitat destruction:

A rare Amur tiger dad hanging out with one of his cubs:

The Organization for Bat Conservation

Episode transcript:

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

This week we’re going to learn about how animals go extinct, with examples of lots of animals who’ve gone extinct and others that have been saved from extinction by human intervention. Both topics were suggestions by Maureen, who also suggested several of the animals I included. I could have kept adding to this episode until it was 24 hours long, but I had to stop somewhere, and now that I’m recording I realize there are aspects of extinction I didn’t address at all.

Extinction means that a population of life forms have all died. That sounds pretty definitive, but it’s also hard to know exactly when it’s happened for any given species. Sometimes you can look online and find the specific day that the very last animal of a species died. In the case of the passenger pigeon, that was September 1, 1914, when a captive bird called Martha was found dead in her cage. Martha had been kept in the Cincinnati Zoo long after the last wild passenger pigeon was shot around 1901. But we don’t know for sure that she was the very last passenger pigeon alive at that point. Passenger pigeons were spotted in the wild for years after Martha died.

The passenger pigeon looks similar to the mourning dove, which is a common and very pretty dove throughout most of North America, but it’s not all that closely related. The passenger pigeon was a swift and elegant flyer but was awkward on the ground. And while mourning doves have a soft, musical call, the passenger pigeon apparently didn’t sound very musical at all. Its calls were mostly loud, harsh clucks that were described as deafening when one of the massive flocks of birds took off in alarm.

So what caused the passenger pigeon to go extinct? As is often the case, it wasn’t just one thing. We’ll come back to the passenger pigeon later, but for now let’s discuss one rather unusual cause that contributed to its extinction.

The passenger pigeon was famous for its numbers. There may have been as many as five billion birds alive at any given time, in flocks that numbered millions of birds each. I’m not exaggerating, either. A single flock could take an entire day to fully pass overhead and literally darkened the sky, there were so many individual birds. With so many birds, it wasn’t that hard for hawks and other hunting birds to catch as many pigeons as they could eat—but there are only so many hawks, and millions upon millions of pigeons. The passenger pigeon also nested in a relatively small area within its eastern North American range. Its nesting colonies were so huge they were called cities. A female laid one or two eggs, which both parents incubated. Sometimes there were so many pigeons in a tree that limbs would break off. By the end of nesting season, pigeon poop underneath roosts could be as deep as a foot, or 30 cm.

And while millions of adult birds were tending millions of eggs and babies, predators gorged themselves on pigeon. Hawks, eagles, owls, and other birds of prey naturally caught lots of pigeons, but other animals moved in to take advantage of the buffet. Bears, foxes, wolves, mountain lions, and smaller animals like possums and raccoons would all eat as much pigeon as they could catch. But there were so many birds that there literally weren’t enough predators to make a dent in the population before the babies could fly and the flocks left the nesting grounds for another year. I mean, birds sometimes just laid their eggs directly on the ground. They were not very hard to catch.

The problem was that once the passenger pigeon’s numbers fell due to other factors, the predators’ yearly glut of pigeon eating started making a difference. The once enormous flocks grew smaller and smaller. And since the passenger pigeon was adapted to thrive in huge colonies, where individuals worked together to gather food and feed babies communally, once the flocks dropped below a certain number, the birds weren’t able to raise their young effectively.

This is depressing, so let’s cleanse the palate with a bird that was saved from certain extinction not too long ago. There are actually a number of species I could have chosen, but I decided on the black robin because it’s tiny, jet black, and has a name that sounds like an alternate-universe DC comic book character.

When I say robin, my North American listeners think of a big thrush-type bird that always looks like it’s frowning, and my European listeners think of a tiny round ball of floof. The black robin is the round ball of floof type, but it’s not from Europe. It’s found only on a few small islands off the coast of New Zealand—really small islands. In 1980, the entire population of black robins lived on Little Mangere Island, which is 279 acres in size, or 113 hectares. Of course, the entire population of black robins in 1980 was five individuals, only one of which was a female. That bird was called Old Blue, and she basically saved her species. A team of conservationists led by Don Merton established a breeding program and today there are more than 250 of the birds.

The black robin was almost driven extinct mainly by introduced predators like cats, rats, and dogs. That’s a common problem, especially in island habitats. Like the dodo, the black robin had never had to deal with mammals that wanted to eat it. It isn’t entirely flightless but it spends most of its time on the ground, digging through brush and dead leaves for insects, and isn’t a very strong flier.

Habitat loss is another huge cause of extinction, and if I wanted to spend all year on this one topic I could. But I won’t, because that would be really grim and not fun at all. One of the factors contributing to the passenger pigeon’s extinction was habitat loss. It mainly ate acorns and small nuts, insects, and seeds found in forests, and when European settlers decided they wanted to turn huge sections of North American woodland into farms and towns, the passenger pigeon soon didn’t have enough forested areas to sustain its massive population. It would have had a hard time as a result even if all other factors had been in its favor.

Habitat loss doesn’t just mean cutting down trees. It can mean polluting a river, bottom dredging in the ocean, diverting water to farmland, and filling in wetlands. It also isn’t always caused by humans. Natural causes like forest fires and volcanoes can lead to habitat loss and extinctions. And many of the dinosaurs, of course, were killed off by a massive meteor impact and its long-term repercussions on climate.

I could choose any of literally thousands of examples of animals that went extinct due to habitat loss, but here’s just one. I mainly chose it because it has a cute name. The Tecopa pupfish was an awesome little fish that lived in California, specifically in the Mojave desert, which is not a place you’d ordinarily expect to find any fish. There are hot springs in the Mojave, though, and the pupfish lived happily in water that was 110 degrees F, or 43 C, or even a little warmer. That’s the temperature of a comfortably warm bath. It ate algae but it also gobbled up mosquito larvae, and it was only about an inch and a half in length, or 4 cm. It didn’t live in the actual hot springs pools, which were too hot, but in a pair of outflows, basically streams that flowed away from the pool down to the Amargosa River.

The problem is, humans really like hot springs. In the 1950s and 60s, people flocked to the Tecopa Hot Springs to soak in the water. Bathhouses were built, the hot springs pools were enlarged, and in 1965, both outflows from the springs were diverted into a single newly dug channel. After that, the water flowed faster. That meant it remained too hot for the pupfish unless the fish moved downstream, and when it moved downstream to where it was comfortable, it had to compete with another subspecies of pupfish, the Amargosa River pupfish. It also had to compete with introduced species of fish.

By 1966, almost no Tecopa pupfish remained. In 1970 it was put on the endangered species list, but by then it was far too late. By 1972 there were no Tecopa pupfish.

Oh my gosh, that’s so depressing. I need another success story. The West Virginia Northern Flying Squirrel is an adorable and fascinating rodent, a subspecies of the more common northern flying squirrel, but it lives only in the highest elevations of the central Appalachian Mountains. During the ice ages, it was isolated from other flying squirrel populations by glaciers and developed separately. It has a broad, flat tail and loose folds of skin that connect its forelegs to its hind legs along its sides. When it jumps from a branch, it holds its legs out to pull the skin folds taut, which allows it to glide through the air.

But it almost died out completely due to industrial logging. By 1985, only ten individuals were found in four different areas of its range. It was listed as a protected species in 1985, and that together with the conservancy of its mountaintop habitats, allowed it to increase to a small but healthy population today.

The West Virginia Northern Flying Squirrel was lucky because its habitat became protected and started to recover from heavy logging, so the flying squirrels were able to stay put and lead their ordinary squirrelly lives. Other species aren’t as fortunate. The Golden Lion Tamarin, for instance, has been snatched from the jaws of certain death but still faces an uphill battle due to habitat destruction.

The golden lion tamarin is a monkey native to the coastal forests of Brazil. It’s a gorgeous monkey with golden-orange fur that grows long around the face so it looks like a lion’s mane. The golden lion tamarin is only around 10 inches long, or 25 cm, not counting its long tail, and it lives in trees where it runs and leaps and climbs a lot like a big golden squirrel.

The problem, of course, is that the Atlantic Forest of Brazil keeps getting cut down. What used to be nearly unbroken forest that stretched for thousands of miles has now shrunk to only around 8% of its original size, and it’s in little bits and pieces widely separated from each other. By 1969, there were only 150 tamarins left.

Fortunately for everyone, especially the tamarins, an aggressive conservation program was well underway by 1984. Zoos throughout the world started breeding golden tamarins for reintroduction into protected wilderness in Brazil. As it happens, while I was still researching this episode, I got an email from a listener that is just so perfect, I have to share it. Emily wrote,

“I used to volunteer at the zoo and I was in charge of making sure the Golden Lion Tamarin monkeys didn’t escape their habitat. There were no fences around it, since they were trying to simulate natural conditions enough so that they could eventually be released back into the jungle. So my job was to walk around the enclosure and shoot them with a water gun. It was set on “very soft.” Just a gentle aquatic nudge to get back in the tree! They were tiny, luxurious creatures and I hated it when my scheduled changed and I had to stop volunteering.”

I love this so much. Thank you, Emily, for sharing the story with me and agreeing to let me use it on the show. I feel like I should pause for a moment so everyone listening can just imagine how awesome it would be to walk around spritzing beautiful little monkeys with water.

Anyway, the population of golden lion tamarins is now over 3,000. And even better, the Brazilian government has made an effort to develop protected wilderness corridors connecting what used to be separate sections of forest. This will help not just the tamarins but lots of other animals too.

Now I feel great. But we’re not done talking about causes of extinction, and unfortunately we’ve reached the worst part: overhunting by humans.

That was the main cause of extinction for the passenger pigeon. People would just shoot up into the air at the seemingly endless flocks of birds. They didn’t even have to aim. Every shot would bring down a rain of dead and injured birds. Almost no one imagined the passenger pigeon could possibly go extinct—there were just too many of them. Even when the flocks were noticeably smaller and the birds’ range had shifted away from the more populated eastern states, professional hunters and trappers continued to follow the flocks and kill as many birds as possible. The dead pigeons were shipped by train to big cities as cheap meat—so cheap that by 1876 it actually cost more to ship a barrel of pigeons on ice than it cost to buy the pigeons when they arrived. By 1878, only one large nesting site remained—and 50,000 pigeons were killed there every single day. No babies survived from that nesting and the surviving adults were killed when they tried to start new nests in another area.

It was senseless. It makes me so mad. But while the passenger pigeon was a great big lesson on how quickly a species can be driven to extinction from an enormous, thriving population, it happens on a smaller scale all the time.

The Caribbean Monk Seal, sometimes called the wolf seal, grew to about 8 feet in length, or 2.5 meters, and had sleek dark gray fur that sometimes looked greenish due to algae growing on it. They were curious, friendly animals that didn’t fear humans, and you can see where this is going. The first European to see the Caribbean monk seal was Christopher Columbus, whose men killed eight seals. The next European to see the Caribbean monk seal was Ponce de Leon, whose men killed 14 seals. Things didn’t get any better from then on.

Seals provided oil from their fat, much like oil made from whale blubber. It could be used to grease machinery or burn in lamps—remember, this was before petroleum products and electricity. Hunting the seals for oil, meat, and skins wasn’t the only problem, though. Conservation back in the 19th century wasn’t all that great. Scientific expeditions usually just killed as many animals as they could find, because that was how they were studied. In only four days, an 1886 expedition specifically made to study seals killed 42 animals and captured a newly born pup that died a week later.

The Caribbean monk seal held on for decades despite the slaughter, but the last one was spotted in 1952 and that was it. Not only were the seals hunted nearly to extinction, the fish and crabs the seals ate were also overhunted. What seals remained had almost nothing to eat and frequently starved to death.

We need a big success story after that one. Let’s talk about the California condor.

The California condor is an enormous bird with a wingspan ten feet wide, or over 3 meters. It’s a scavenger so it looks superficially like a vulture, with a bald head. Its feathers are black with white patches under the wings, and it has a floof of feathers around its neck that looks precisely like it’s wearing a really fancy opera cape. By 1987, the entire world population of the California condor was 27 birds. And those 27 birds were not going to survive long without help. Poaching and habitat loss had almost wiped them out, along with poisoning from lead bullets—the birds would eat the bullets frequently left in the discarded guts after a hunter field dressed a kill.

So all 27 birds were captured and placed into a breeding program, although only 14 birds were able to breed. By 1991 there were enough condors that individuals started to be released into the wild again. Currently there are almost 450 birds total.

Fortunately, in 2019 California hunters will no longer be allowed to use lead bullets at all, and a lot of hunters have already started using lead-free ammunition. This will allow more condors to be released in areas of California where they used to live but were hunted to extinction over a century ago. Lead poisoning is a big problem for all scavengers, including bald eagles.

Our last success story is the Amur tiger, also called the Siberian tiger. It had a lot of names in the past because its range was so large, from Korea to northeastern China, eastern Mongolia, and parts of Russia. It’s a big tiger, as big as the Bengal tiger in the past although the remaining population of Amur tigers is overall smaller than Bengal tigers today. Its head is broad, with a skull similar to a lion’s. Its coat color and markings vary considerably, and its winter coat grows very long and shaggy.

The Amur tiger was already under pressure from hunting and habitat loss when the Russian Civil War broke out in 1917. Tigers were either killed by accident during the fighting, or killed by soldiers on patrol, almost wiping out what animals remained. And after that, tiger hunting wasn’t prohibited until 1947, at which time only a few dozen tigers were left.

Fortunately, it survived. In 2007 the Russian government even set aside a national park just for the Amur tiger. No human activity is allowed in most of the park and tiger numbers are climbing. In 2015, a logging company agreed to dismantle abandoned logging roads so they couldn’t be used by poachers. Bridges were removed, trenches dug, and some areas were simply bulldozed so that vehicles can’t get through. That’s the same year that camera traps got rare photos of an adult Amur tiger male, a female, and three cubs. Since male tigers are usually solitary, that was pretty awesome.

Genetically the Amur tiger is very similar to the extinct Caspian tiger. There’s a possibility that as the Amur tiger’s population grows, it could be reintroduced to parts of Asia where the Caspian tiger once lived.

That brings me to something I meant to mention in last week’s episode. If you listened to the recent Relic: The Lost Treasure podcast episode where I was a guest, you heard me absolutely mangle an explanation of what a subspecies is. So here’s my attempt to clarify what I was trying to say. A subspecies develops when an animal population becomes isolated from the rest of the population for long enough to start evolving in different ways from the parent population. A subspecies can still produce fertile offspring with the parent species and other subspecies of the same species, and may look almost the same, but on a molecular level it’s different enough that if given enough time, it will continue to develop into a different species.

It’s a complicated topic and I said the word species too many times. But hopefully that gives you an idea. Technically humans are a subspecies of Homo sapiens, by the way. Our official scientific name is Homo sapiens sapiens. The extra sapiens indicates that we’re a subspecies and that we’re extra smart, because sapiens means intelligent. All tigers are subspecies of the species Panthera tigris, and the Bengal tiger is called Panthera tigris tigris, because I guess they’re extra tigery.

Anyway, it’s important to remember that while a subspecies may look almost identical to the parent species, it’s developing in different ways due to different evolutionary pressures in its specific habitat. The dodo’s ancestor was a type of pigeon that decided to stay on the island of Mauritius. It probably continued to look like a pigeon for a long time before its evolutionary changes started to show. It’s easy to think that a subspecies going extinct isn’t as important as a full species going extinct, but that’s not the case.

Thinking about extinction can make us feel angry and helpless. But there are lots of things you can do to help, simple things like picking up trash when you’re out hiking, remembering to bring your reusable bags into the grocery store, and using a refillable water bottle instead of buying a new plastic bottle of water. If you have some extra money, there are lots of good conservation organizations that can use a donation. One I try to donate to every year is the Organization for Bat Conservation. I’ll put a link to it in the show notes if you’re interested. If you don’t have extra money but can donate your time to a local organization, that’s just as good. Although you probably won’t be lucky enough to get to spritz monkeys gently with water.

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 iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 042: Mystery Bears

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This week we’re going to learn about bears, including a bunch of m y s t e r y  b e a r s!

Hi! I am a panda bear!

A polar bear:

A spectacled bear:

A baby spectacled bear OMG LOOK AT THAT BABY:

The giant short-faced bear was indeed giant:

Further reading:

Shuker Nature

Show transcript:

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

I’m in the mood for a bona fide mystery animal, and I bet you are too. So this week let’s learn about some mystery bears.

There are eight species of bears alive today that we know of: brown, polar, spectacled, sloth, sun, Asian and American black bears, and the giant panda. The other ones you may have heard of, like grizzlies, are subspecies of those eight. For a long time pandas were not considered bears at all, but more closely related to raccoons. These days they’re definitely in the bear box, but they’ve evolved in a completely different direction from other bears for some 19 million years, which is why they’re so different.

Before we get into the mysteries, let’s talk about just how different pandas are from other bears. As you probably know, the panda eats bamboo almost exclusively, unlike all other bears which are either omnivorous or, in the case of the polar bear, carnivorous. To survive on bamboo, the panda has evolved a lot of unusual adaptations. The front paws, for instance, have five toes just like all bears, and also a thumb. The thumb is actually a modified wrist bone that juts out from the base of the paw and helps the panda hold bamboo stalks as it eats the leaves.

Bamboo is not very nutritious. It’s certainly low in protein, especially considering that while the panda eats almost nothing but bamboo, it still has the digestive system of a carnivore. Special microbes in the panda’s intestines help break down the bamboo so the panda can digest it, but it takes a lot of bamboo to provide the energy a panda needs. A panda eats 20 to 30 pounds of bamboo leaves, stems, and shoots every day, or 9-14 kg, which means it also poops a whole lot. Seriously, it poops something like 40 times a day. And it still doesn’t have a lot of energy. It mostly just sits around eating and pooping. But while the panda just chews leaves all the time, it still has bear fangs and it will eat meat and eggs when it can. Researchers think that the panda only became exclusively a bamboo eater about two million years ago.

The panda lives in the mountains of China in only a few places. It used to also live in the lowlands but farming and other development drove it into more remote areas. There are about 50 pandas in captivity these days and somewhere between 1,500 and 3,000 pandas in the wild, with the population finally increasing after laws protecting pandas from poaching started to be enforced.

The people of China knew about the panda for centuries, although they were considered rare and elusive even in the olden days, but it wasn’t until 1869 that anyone from outside of China had a clue that gigantic roly-poly black and white bamboo-eating six-toed bears were real. Seriously, would you believe that? In 1869 a French missionary and naturalist bought a dead panda from some hunters, dissected it to study, and sent the skin to a zoologist friend in Paris.

So it’s possible that there are other mystery bears out there, known to the locals who don’t realize their bears are special, just waiting to be spotted by someone who knows a thing or two about bears.

In 1920 a Swedish scientist named Sten Bergman was shown the pelt of a bear by locals during an expedition to the Kamchatka Peninsula. That’s in the very eastern part of Russia on the Pacific coast and is sparsely populated. It’s mountainous with a cluster of active volcanos and it’s well known for the brown bears that live in the area. The Kamchatka brown bears are among the largest brown bear subspecies in the world, almost the size of the closely related Kodiak brown bear. When it stands on its hind legs it can be almost ten feet tall, or 3 meters. It’s mostly harmless to humans. Mostly. It hardly ever kills people. Just, you know, occasionally. The Kamchatka brown bears have long brown fur, sometimes pale brown but usually a sort of medium brown. They’re certainly not black. But the pelt that Dr. Bergman was shown was jet black and had short fur. But it was definitely a bear pelt, and the pelt was definitely enormous—much larger than a brown bear pelt. Bergman also saw a huge skull supposedly from one of the black bears, and a paw print 15” long and 10” wide, or 38 cm by 25 ½ cm.

Unfortunately none of the giant black bears have turned up since, living or dead. It’s possible that the bear was an unusually large brown bear with anomalous fur. Brown bears do have considerable variability in both the color and length of their fur, so it’s not out of the question that occasionally a brown bear is born that is actually black. It’s also possible that this black bear is actually a different species of bear, but that it’s either gone extinct or is extremely rare and only lives in far remote areas of Siberia these days.

But the Kamchatka Peninsula has another mystery bear for us to ponder. In 1987 a hunter named Rodion Sivolobov bought a giant white bear skin from locals. It looked like a big polar bear pelt, but the locals assured him it was from a very specific, very rare type of local bear.

They called it the irkuiem and described it as large but with a relatively small head, relatively short hind legs, and an unusual method of running. It supposedly runs in a sort of rocking motion, bringing both hind legs up to the forelegs, then throwing the forelegs forward together to start a new stride–more like a rabbit’s bounding run than a bear’s typical gait.

Sivolobov sent samples of the pelt to various zoologists in Russia, but they said there wasn’t much they could determine without a skull. But with DNA testing so much more advanced these days, it would be REALLY NICE if Sivolobov would get right on that and get his white bear pelt tested. If it really exists and if he’s not scared he was sold a marked-up polar bear skin with a tall tale.

The polar bear lives in the Arctic and is so closely related to the brown bear that the two species occasionally crossbreed when their range overlaps. Technically polar bears are marine mammals since they hunt seals on sea ice and spend a lot of time in the water. Sometimes a polar bear will drift for long distances on a piece of sea ice, or may swim for days, crossing hundreds of miles of ocean.

Polar bear feet are huge, around 12 inches wide or 30 cm, which helps keep the bear from sinking in the snow since its weight is more widely distributed on broad paws. Think snowshoes. Broad feet also helps it swim faster. The paw pads are bumpy so it’s less likely to slip on ice, and the claws are short and strong for digging in snow and ice. The polar bear stays warm because its body is heavily insulated with fat, plus its fur is thick with a soft undercoat that insulates so well that polar bears really are virtually invisible to heat-sensing radar. Male polar bears grow long fur on their forelegs, apparently because lady polar bears find that attractive. Unlike most other bears, polar bears don’t hibernate.

Georg Wilhelm Steller was a German naturalist who took part in explorations of Kamchatka Peninsula and other areas. He’s the guy that Steller’s sea-cow is named after and one day it’s getting its own episode. Anyway, in 1751 Steller wrote a book called, in English, Beasts of the Sea, and in it he mentions a report of a white sea-bear. He didn’t see it himself, but here’s his account, which I’ve taken from Karl Shuker’s excellent blog ShukerNature. I’ll link to it in the show notes.

Here’s the quote:

“Report, as I gather from the account of the people, has declared that the sea-bear, as it is called by the Rutheni and other people is different. They say it is an amphibious sea beast very like a bear, but very fierce, both on land and in the water. They told likewise, that in the year 1736 it had overturned a boat and torn two men to pieces; that they were very much alarmed when they heard the sound of its voice, which was like the growl of a bear, and that they fled from their chase of the otter and seals on the sea and hastened back to land. They say that it is covered with white fur; that it lives near the Kuril Islands, and is more numerous toward Japan; that here it is seldom seen. I myself do not know how far to believe this report, for no one has ever seen one, either slain or cast up dead upon the shore.”

Shuker suggests that this report may actually be of a fur seal, which is found in the area and has sometimes been called a sea-bear. Then again, fur seals aren’t white. They’re gray or brown and would appear darker in the water.

The Kuril Islands are a string of 56 volcanic islands that stretch between the northeastern tip of Hokkaido, Japan to the southern tip of Kamchatka Peninsula, a distance of about 810 miles, or 1300 km. Some of the largest islands are inhabited by brown bears, but it’s far from the Arctic. Polar bears get overheated easily in warmer areas, so a population of polar bears—or even a stray one—is unlikely that far south.

There are also stories of pure white bears in the forests of Hubei province in China. It’s always possible this is a garbled account of the panda, but maybe not.

In 1864, Inuit hunters supposedly killed a huge bear with yellowish fur. Naturalist Roderick McFarlane acquired the skin and skull and sent them to the Smithsonian, which promptly lost them. That’s the story, anyway. In fact, the Smithsonian did misplace the skin and skull for a while, but zoologist Clinton Hart Merriam found and examined them. He decided it was a new species of bear due to the skull’s odd shape and the light tan color of the fur.

Older polar bears do tend to have yellowish fur so maybe that’s all this bear was. But it might have been something else. As I mentioned earlier, polar bears and various subspecies of brown bear do sometimes crossbreed and produce fertile young. It’s rare, but it happens occasionally both in the wild and in captivity. The resulting babies show traits of both polar bears and brown bears, and tend to be pale brown or tan in color with darker brown paws. Then again, there’s a MonsterQuest episode that I haven’t actually seen where a paleontologist examines the McFarlane skull and states it’s just that of a young female brown bear.

For having only eight species, bears are remarkably widespread and vary considerably in diet and appearance. The sloth bear mostly eats insects, for instance. It lives in India and has shaggy black fur with a pale muzzle and white claws, big floppy ears, and a white V-shaped mark on the chest. It lacks upper incisors, which helps it slurp up insects.

Sloth bears are actually pretty darn awesome. Males often help raise the cubs and mothers carry their babies around on their backs. The sloth bear doesn’t hibernate, probably because it doesn’t really get cold where it lives.

The spectacled bear lives in South America. It’s the last close relative of the giant short-faced bear that went extinct about 11,000 years ago. The spectacled bear is mostly black, although some individuals may appear brown or reddish, and most but not all have lighter markings on the face and chest. Its head is much less bearlike than other bears, with a rounded face and short snout. It mostly eats plants and lives in the Andes Mountains and surrounding areas. It spends a lot of time in trees, and will even build a little platform in a tree to sleep on or store food on.

And you know what? Paddington Bear is modeled on the spectacled bear.

The spectacled bear is not especially scary. Its relative, the giant short-faced bear, was another story. It lived in North America, especially in California, and its remains have been found in the La Brea tar pits. But it also lived as far south as Mississippi. And it was huge. It was simply enormous. It stood up to 6 feet at the shoulder, or 1.8 meters, and twice that when standing on its hind legs. One website I read pointed out that regulation height for a basketball rim is ten feet, which means a giant short-faced bear could dunk the ball every time without doing anything more strenuous than standing up. It was probably an omnivore like most modern bears, but we have mastodon bones that show tooth marks from the short-faced bear.

Naturally, as with just about any extinct animal, people keep hoping they’re not really extinct and occasionally someone reports seeing a giant short-faced bear. Some cryptozoologists speculate that the Kamchatka Peninsula mystery bears may actually be short-faced bears, but since short-faced bear fossils have only been found in North America, it’s probably not likely that there would be any living in Russia. Besides, the short-faced bear would have looked very different from the brown bear, probably shaped more like a colossal spectacled bear. Locals would definitely notice the difference. Moreover, it’s not likely to live in the same area that already has a population of brown bears, since both animals would then be competing for the same resources.

Personally, while the giant short-faced bear is awesome to imagine, I’m perfectly happy with it not wandering around in the forests. Because I like to hike. And I worry enough about the relatively small and harmless American black bear as it is.

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 iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 041: Comb Jellies and Sea Sponges THE CONTROVERSY

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We’re learning about comb jellies this week, along with the sea sponge, and the MASSIVE CONTROVERSY ABOUT THE TWO THAT IS PITTING SCIENTIST AGAINST SCIENTIST I might be overstating it just a bit

The lovely Arctic comb jelly:

The lovely Venus’s girdle comb jelly:

A fossil comb jelly. Probably lovely when it was alive:

A sea sponge (most are not this Muppet-like):

Show transcript:

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

For this week’s episode, we’re revisiting jellyfish, more properly known as jellies. The first jelly episode is far and away our most popular and I can’t figure out why. I mean, I’m glad people like it. This time, we’re going to learn all about comb jellies, which are not really as exciting as true jellies. There is no ship-sinkingly enormous comb jelly lurking in the oceans of the world. But they are really interesting.

When you think of a jelly, you probably picture a roughly bell-shaped thing with long stinging tentacles. But most comb jellies are more like egg-shaped blobs, and either don’t have tentacles at all or only have relatively small tentacles that don’t sting. Although they look alike superficially, comb jellies and true jellies are so different that scientists don’t think they’re very closely related at all. Comb jellies are officially called ctenophores (TEN-oh-fours), spelled with a c-t at the beginning if you were wondering. I looked up the pronunciation. Yeah, I know, I pronounced Pliny wrong all through episode 12, but come on, it looks like it should be pronounced Pliny and not Plinny. It’s not like anyone ever came up to me and said, “Hey, what about that Plinny, what a guy.” I just read the name.

But I digress, inexplicably.

Instead of pulsing its bell to maneuver in the water, a comb jelly has rows of tiny compact filaments called cilia, fused together in combs that help it swim. The combs are also called swimming plates.

There are two main types of comb jellies, those with tentacles and those without tentacles. The ones without are called Nuda, or Beroids, and while they don’t have tentacles, they do have combs of extra-large cilia, called macrocilia, that sever prey into pieces small enough to swallow. Mostly they eat other comb jellies. Beroids also have big mouths, but a beroid can actually seal its mouth shut while it’s moving so it’s more streamlined.

Comb jellies with tentacles are divided into eight orders roughly based on body shape. The most common order, the cydippida, are egg-shaped with a pair of thin tentacles that they use sort of like fishing lines. The tentacles are long and sticky, trapping tiny organisms or particles of food. Some species have branched tentacles but none have more than two. The tentacles can retract—when you see a picture of a comb jelly with a weird spring-like thing sticking out from its bottom, that’s a retracted tentacle, not anything gross like a poop. The tentacles contain cells called colloblasts. When an organism touches a tentacle, the colloblast cells rupture and basically release glue that keeps the prey from escaping.

A cydippid comb jelly also has eight combs that run from the top of the body to the bottom, which makes it look sort of like a fancy decorated egg. Comb jelly cilia are iridescent, by the way, so they reflect light in rainbow patterns. Basically what I’m saying is, these little guys are actually really pretty.

All comb jellies are predators, but most eat plankton and other tiny food, because most comb jellies are really small—only a few inches long at most. Bigger species may eat krill and small crustaceans. The biggest comb jelly, Cestum veneris, more often called Venus’s girdle, can grow some five feet long, or 1.5 meters, but only some two inches, or 5 cm, wide. It looks like a nearly transparent or purplish ribbon and lives in tropical and subtropical seas. I wouldn’t want to touch it, but it’s not exactly dangerous. In fact, it’s so delicate that a diver attempting to touch one may accidentally destroy it instead. A lot of comb jellies are that delicate, making them hard to study, so we still don’t know a whole lot about them.

Comb jellies only have one body opening, called a mouth for convenience sake although the jelly uses it for anything that requires a body opening. Until recently, researchers thought that included pooping. Yeah, now you see why it’s not exactly a mouth. But it turns out that a comb jelly has pores on the opposite end of its body from its mouth opening that it uses to release at least some particles of indigestible food. This is interesting since it helps scientists understand how the anus evolved.

There aren’t that many species of comb jellies, maybe 100 or so. But new ones are discovered occasionally, especially deep-sea comb jellies. While comb jellies that live near the surface of the ocean are usually transparent, many deep-sea species are red, since it’s a color most deep-sea animals can’t see. Most are also bioluminescent, and when threatened some species will secrete a luminescent goo. The predator may get confused and attack the goo while the comb jelly swims away as fast as its frantically waving cilia can take it.

If you’ve listened to episode 15, about the hammerhead shark and megalodon, you’ll remember that we don’t have a lot of shark fossils because shark skeletons are made of cartilage, not bone. We just have a lot of shark teeth, mostly. Now think about how big and solid sharks are, then think about how smooshy jellies are. Then try to imagine what a jelly fossil might look like. Yeah.

We do have some comb jelly fossils, though. But we don’t have many. Like, five. We have five. The oldest are from the mid-Cambrian, some 500 million years ago, but they were very different from the comb jellies living today. They had lots more combs, for one thing—between 24 and 80 instead of 8. Researchers have found other fossils that may be of comb jellies. There’s a good possibility that they were widespread throughout the oceans back then—but from genetic testing and other molecular analysis, it appears that the comb jellies alive today are all descended from a common ancestor that survived the Cretaceous-Paleogene extinction around 65 million years ago. So it’s possible that in addition to so many dinosaurs dying off, almost all comb jellies went extinct then too.

Just think, if that one species hadn’t survived and evolved into the comb jellies we have today, researchers might not have a clue what animal those comb jelly fossils represented. If you know about the Burgess shale fossils that have baffled and fascinated paleontologists for decades now, because so many of the fossils don’t resemble anything living today, then it’ll make sense to learn that a few of those five comb jelly fossils were actually found in the Burgess shale.

There are some other comb jelly fossils discovered in China and dated to 520 million years ago. But they don’t resemble the comb jellies living today at all because they had skeletons and spines. Pretty much every fossil found from the Cambrian had supportive or armored structures, even ones like comb jellies that don’t have those things today. I’ll probably do a whole episode eventually about the Cambrian period and the Burgess shale discoveries.

Anyway, there’s some controversy going on right now regarding whether comb jellies or sponges were the species that gave rise ultimately to all other animals, so let’s take a quick side trip and learn about sponges.

The sponge is a very simple animal, still around today. They don’t have any specialized structures like nerves or a digestive system or a circulatory system or organs. They’re just a sponge, basically. And if you were wondering, the sponge you use to clean your kitchen is named after the sea sponge, not vice versa, and you can still get actual dried sea sponges to use for cleaning. They’ve been used that way for millennia. It wasn’t until 1866 that scientists even realized sponges were animals and not plants.

Living sponges just hang out in the ocean or freshwater, stuck to a rock or something. Water flows through them and washes food and oxygen in and waste out. That’s it. That’s all a sponge does is let water flow through it. I feel like there’s a life lesson to be learned there, but I’m too busy doing ten things at once to figure it out.

Mostly sponges eat bacteria and other tiny food particles, although some eat small crustaceans and a few have developed a symbiotic relationship with plantlike microorganisms, which live safely in the sponge and produce enough food for both it and the sponge. Every so often a sponge will release eggs or sperm into the water. If the conditions around a sponge deteriorate, some species will create bundles of unspecialized cells called gemmules. When conditions improve, the gemmules will either grow into new sponges or, if the sponge that created them has died, it will recolonize the original sponge’s skeleton.

A sponge’s skeleton is a sponge, by the way. If you’ve got a natural sea sponge in your house, that’s what you’re cleaning your kitchen counters with, the skeleton of a sea sponge. Different sponges use different minerals to create their skeletons and most are pretty hard, but the ones sold as natural sponges are softer and throughout history have been used for everything from padding armor, applying paint, and filtering water. Loofah sponges aren’t actually made from sea sponges, though. They’re actually from the dried insides of the sponge gourd. I did not actually know that until just now.

Oh, and guess what else I just learned? There’s a small population of bottlenose dolphins in Western Australia that use sponges. The dolphins frequently hunt close to the bottom of the bay. To keep from scraping its rostrum, or bill, in the sand, a dolphin will sometimes stick a sponge under its chin. Researchers think that one especially smart dolphin figured this out and has been teaching her children how to do it ever since.

So that’s the sea sponge. Useful for many things, not much of a party animal. Compared to sea sponges, comb jellies are intellectual masterminds. Even though comb jellies don’t have brains.

Instead, comb jellies have a nerve net. The nerves are concentrated around its mouth and on its tentacles. It does also contain an organ that helps the jelly sense its orientation, basically so it knows which way is up. It usually swims with its mouth pointing upward, incidentally. But while the comb jelly’s nervous system is pretty sophisticated for such a simple animal, it’s also very different from other animals’ nervous systems. Like, super different. Its nerves are constructed from different molecules and use different neurotransmitters.

Its nerve cells are so different from other animals’ that some researchers think it actually evolved separately. Specifically, neuroscientist Leonid Moroz thinks so. He thinks that the first ancestor of comb jellies split off from the sea sponges some three quarters of a billion years ago and evolved separately from all other animals.

Since comb jellies use a different set of chemicals as other animals to accomplish the same tasks, a couple of articles I read make a big deal about how evolution must therefore follow a prescribed path—that animals must have certain traits to survive. But assuming comb jellies did split off from sponges that early and did evolve separately from other animals, they were still competing against those other animals. It’s not like they had an ocean to themselves, although that would be awesome if they did, because who knows what they might have evolved into?

The controversy about whether sea sponges or comb jellies were basically the trunk of the tree of animal life started in 2008, when a study in the journal Nature compared DNA sequences across a number of animal species and suggested that the comb jellies were evolutionarily first. A 2013 paper published in Science by another team of researchers made the same conclusion based on the genome of a species of comb jelly called the sea walnut. That is such a cute name. Don’t you just want to cuddle the little sea walnut and make little hats for it?

All this ignited what some articles call a firestorm of controversy. I like to imagine researchers reading the articles and FREAKING OUT. Moroz’s studies of the comb jelly’s nervous system, and the complete genome of a different comb jelly, the sea gooseberry, appeared in Nature in 2014. Moroz now thinks that nervous systems have developed independently at least nine times in various different groups.

The controversy at this point appears to have several factions. Moroz’s group thinks comb jellies split off from sponges, and that everything else split off from comb jellies but developed separately in the neurological sense. Another group thinks comb jellies split off from sponges and everything evolved from comb jellies, and that comb jellies aren’t all that weird neurologically. Another group thinks comb jellies and sponges split off from a common ancestor of both that had a simple nervous system, which comb jellies retained but sponges lost, and that everything else evolved from comb jellies. But then there’s the other side, the ones who think sure, comb jellies split off from sponges, but so did everything else ultimately, and comb jellies are no more the base of all animal life than the man in the moon.

One thing everyone agrees on, though, is that we still don’t know enough about comb jellies. And they are really pretty.

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 iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

Thanks for listening!

Episode 037: The Dobhar-Chu

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This week we’re in Ireland learning about the dobhar-chú, a vicious creature that might be an otter but might be a KING otter! Either way, it’s a killer.

The weird creature carved on Grace Connolly’s gravestone:

How can such an adorable floof be so MURDEROUS? Eurasian otter:

The giant otter (from South America) imitating a sea serpent (hmm):

Giant otter has teeth:

Further reading:

The Search for the Last Undiscovered Animals by Karl PN Shuker

Show transcript:

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

We’re one week closer to Halloween, and it’s time to learn about a mysterious, deadly animal from Ireland called the Dobhar-chú (pronounced do-war-coo). Appropriately enough, our story starts in a graveyard.

Conwall Cemetery is in the town of Drummans, near the valley of Glenade. In the cemetery is a sandstone grave marker lying flat on the ground. It’s about 4 ½ feet wide and nearly two feet high, or 1.37 by .6 meters, and is dated September 24, 1722. The name on the stone is Grace Con, wife of Ter MacLoghlin. But the main part of the stone is made up of a carving of an animal.

I’ll put a picture of the carving in the show notes. It’s not very clear, but basically, it looks like a heavy-bodied dog with limbs folded beneath it as though it’s crouching. It has a long tail although that has mostly worn off. Its head is small, with tiny ears, and its neck is folded back so that its head lies along its back. A hand holds the hilt of a sword that is plunged into the animal’s neck, with the tip of the sword just visible below the belly.

There are various stories and poems about what happened to Grace Con, or Grace Connolly, but they’re all basically the same. Incidentally, it was Gaelic custom for women to retain their maiden names, which is why Grace’s last name doesn’t match her husband’s.

One morning Grace went down to the lake either to wash or to do laundry, reports differ. When she didn’t return home, her husband Terence McGloughlan went to find her. But when he reached the lake, he found his wife’s body–with a monstrous animal, the dobhar-chú, feeding on it. Terence killed the beast, but as it died it gave a piercing whistle or squeal. The squeal was answered by another animal from the lake, which surfaced and charged Terence.

He fled home just ahead of the monster, leaped on his horse, and galloped away with the monster pursuing. Eventually his horse tired, so Terence dismounted and turned the horse sideways across the road to act as a sort of shield. When the dobhar-chú ducked to run beneath the horse’s belly, Terence stabbed it through the heart.

Dobhar-chú is an Irish term meaning water-hound. It’s used as a name for the Eurasian otter, but can also refer to something called a master otter or king otter. But before we go any farther, let’s get some background on the otters that live in Ireland and Scotland, since the legend of the dobhar-chú is known in both places.

The Eurasian otter lives throughout Europe and Asia. It’s shy, solitary, and territorial. It’s a pretty big animal, and some big adult males can grow as long as four and a half feet, or 1.4 meters, including the tail. Females are smaller. The otter’s toes are webbed, which makes it a good swimmer. It’s dark brown above, grayish-brown below, with white or cream-colored markings around the throat and cheeks. It has a long, slender body and flattened head with tiny ears and sensitive whiskers. Oh, and it’s incredibly cute. Oh my gosh is it cute.

The otter eats fish, frogs, and invertebrates like crayfish. It lives in rivers and lakes and likes plenty of cover around the water’s edge. While it prefers fresh water, it will enter the ocean, but it needs fresh water both to drink and to clean salt from its coat. It’s usually nocturnal and is especially active at dusk and dawn, although if an otter’s territory is along the coast it will be more active during the day since it forages in rock pools at low tide for fish and invertebrates. Sometimes people call otters who live along the coast sea otters, but in Great Britain and most of Europe they’re the same type of otter that lives in freshwater.

Instead of having one den, an otter’s territory has a number of places where it sleeps or just hangs out. Above-ground areas are called couches and are well hidden in dense vegetation and frequently on small islands. Underground areas are called holts. A holt might be dug into a river bank, among a big tree’s roots, or just be a crevice among fallen rocks. A mother otter will have her babies in a holt that’s fairly remote from her usual activities. She usually has two or three babies at a time, called cubs.

An otter marks its territory with droppings that actually smell nice, like new-mown hay. I have not smelled them myself so I can’t vouch for this. The droppings are called spraints. While otters were once common throughout Europe, they’re much rarer these days, mostly because they can’t live in polluted streams, and these days they are totally protected. You’re not even allowed to damage an otter’s couch or holt, much less the otter itself.

Now we know about the otter, but what’s a master otter? According to Irish and Scottish folklore, it’s basically a super-otter. It’s much larger than a regular otter and sometimes appears with scores of regular otters as though leading them, and it may have some magic powers. Carrying its pelt, or part of its pelt, is said to protect someone from injury or shipwreck. One description says it’s white except for black ear tips and a black cross on its back, another says it’s half wolf, half fish. One account from 1684 calls it an Irish crocodile and describes it as “of the pitch of an ordinary greyhound, of a black slimy skin, without hair,” and says it’s also called a water-dog or Anchu. Whatever it is, it’s rare and dangerous.

So what might it be? As it happens, there is a species of otter that sounds a lot like the dobhar-chú. It’s called the giant otter, and while these days a big male is not much more than about 5 and a half feet long, or 1.7 meters, in the past before they were nearly driven extinct for their fur, big males sometimes grew eight feet long, or 2.4 meters. Those lengths don’t even include the tail. The giant otter is brown or reddish in color, but when it’s wet it looks black. It has a white pattern on its throat that individuals use to identify each other, because unlike other otters, the giant otter is social, communicates with its clan members with whistles and other noises, is mostly active during the day, and can be aggressive. All this sure sounds like the dobhar-chú. The only problem is, the giant otter lives in South America, an entire ocean away from Europe.

Could a similar species of giant otter have once lived in Ireland and Scotland? We don’t have very many otter fossils, unfortunately–but we do have a recently discovered fossil of a new otter species from China. It’s been named Siamogale melilutra and it’s twice the size of the giant otter. From its teeth, it probably ate a lot of freshwater shellfish. The fossil dates to 6.24 million years ago, so it’s not likely that it was running around in Ireland in the early 18th century. But it’s interesting to know that really big otters did once exist in Asia, so it’s always possible that a species of rare giant otter also lived in parts of Europe until fairly recently.

Of course, it might be that the dobhar-chú really is just a folktale and not based on a real animal at all. Some accounts of a king otter say it’s the seventh cub of an ordinary otter, and the king otter’s magical attributes also push it farther into the realm of folklore than objective reality. It’s also possible that the dobhar-chú and the king otter are completely different animals, one real, one a folktale, with some confusion between the two since that’s just how people think.

I’m inclined to think that might be the case. So if we assume that the dobhar-chú is just an unusually large otter, does it fit the reported story? Do otters ever attack people?

Otter attacks are extremely rare, and usually only occur if a mother otter feels someone is threatening her cubs. In North America, where the river otter is very similar to the Eurasian otter, only 44 documented cases of an otter attacking a human have been recorded since 1875. Then again, when an otter does attack it can actually kill a human. Heck, the North American river otter occasionally kills alligators. An otter’s bite is similar in strength to that of a big dog, and it will chase people for at least a short distance if provoked. It can run 18 mph, or 30 km per hour. Usain Bolt can sprint 28 mph, or 45 km per hour, but most of us are a lot slower no matter how motivated we are.

In August of 2016, a Quebec woman swimming in a lake was attacked by an otter that repeatedly bit her legs until she managed to reach a dock with a ladder. Fortunately the otter didn’t chase her once she left the water. Needless to say, this is extremely unusual behavior for an otter, but it does happen. In 2014 an eight-year-old boy and his grandmother were swimming in a river in Washington state when an otter attacked the boy. When his grandmother came to his rescue, the otter turned on her. In 2013 a woman swimming in Yellowstone National Park was bitten and clawed by an otter. Her face, arms, and hands were bitten and some bones in her right hand broken. Fortunately, all these people recovered fully, but all of them had to spend time in the hospital.

So if Grace Connolly was in the lake back in 1733, bathing or washing clothes, and an otter took exception to her presence, it might well have killed her. The rest of the story might be embellishment or the otter might have also chased or attacked Grace’s husband before he managed to kill it. Either way, I don’t think we need to hypothesize about a rare giant otter in this case. A regular otter in a bad mood is scary enough.

Those little guys are cute as all get out, but don’t get too close. They bite.

Next week we’ll take a look at another water monster, this one from the sea–a weird and hideous two-legged fish thing–as we get closer and closer to Halloween.

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 iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

Thanks for listening!

Episode 034: Saber-Toothed Animals

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This week we’ve got a heaping helping of animals with big pointy teeth! Whether you spell it saber or sabre, you don’t want teeth of that description biting you.

Smilodon is the best saber-toothed cat:

Thylacosmilus’s weird chin bone:

Thylacosmilus might have looked something like this when alive:

Kolponomos might have looked something like this when alive:

And the sabertooth fish is still alive!

Show transcript:

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

For this week’s episode, we’re looking at saber-toothed animals. The animal people generally think of as THE saber-tooth cat, or saber-tooth tiger, is Smilodon fatalis. Smilodon and its relatives were members of the feline family, although not very closely related to the big and little cats living today. We have a whole bunch of Smilodon fossils, many from the La Brea tar pits in California.

Smilodon was probably descended from a saber-tooth cat called Megantereon, which lived in North America, Eurasia, and Africa. It might have still been around only half a million years ago, was definitely around as recently as 2.5 million years ago, definitely around as long as 4.5 million years ago, and recent finds have been tentatively dated to 7 million years ago. So Megantereon was a very successful animal. It was stocky with strong forelimbs and neck, with long upper canines—not as big as Smilodon’s, but certainly saber-toothed. It wasn’t a giant cat, probably close to a jaguar in size, with males probably being around 5 or 6 feet long (or around 1.5 meters) not including the tail and a little over 2 feet high at the shoulder, or 72 cm. It probably killed its prey by leaping on it and biting its throat.

Megantereon probably acted a lot like a leopard, including climbing trees, but its descendant, Smilodon, was too heavy for tree-climbing. Smilodon was a big, tough kitty about the size of a modern lion. It lived in North America, and migrated into South America at some point too. It probably looked more like a bear than a cat since it was stocky, heavily muscled, and had a broad head and jaws that could open much wider than modern cats’.

Smilodon cubs didn’t have saber teeth. A cub only started growing its big teeth when it was around a year and a half old, and by around three years old the fangs were fully grown, about 7” long or 18 cm. Very few remains of young Smilodons have been found in the La Brea tar pits, so researchers think cubs were mostly fed and cared for by their mother until they had fully grown fangs and had learned to use them.

For a long time researchers thought Smilodon lived in forested areas, but recent studies show that it probably preferred open areas. One 2016 study compared carbon and nitrogen isotopes found in collagen samples from bones of Smilodon and other predators with those of prey animals in South America to find out what they were eating. It turns out that Smilodon ate a lot of Megatherium and other giant ground sloths, as well as a camel-like ungulate called Macrauchenia. There’s even some evidence that Smilodon may have hunted in family groups. Overall, the finding suggests that Smilodon lived a lot more like modern lions do than like other big cats.

The first Smilodon fossils found date to around 2.5 million years ago, but remains found in Florida dated to 5 million years ago have recently been described as a related saber-toothed cat. Smilodon lived until only 10,000 years ago at the end of the Pleistocene. It preyed on ice age megafauna and researchers think it may have died out when its main prey animals went extinct. Humans probably had something to do with their extinction too.

Smilodon wasn’t the only big predator in North America during the ice age, though. It wasn’t even the only big feline predator. It shared its territory with the American lion and the American cheetah. Neither of those had saber teeth but they’re awesome so I’m going to tell you a little bit about them anyway.

The American lion died out at the same time as much of the other ice age megafauna, around 11,000 years ago. Unlike Smilodon, it’s closely related to modern big cats—in fact, most researchers consider it a subspecies of the modern African lion. We don’t know for sure if the males had manes, but we do know that the American lion was much bigger than modern lions although not as heavy as Smilodon. It probably stood almost four feet tall at the shoulder, or 1.2 meters. Remains of American lions have been found in the La Brea tar pits so we know they shared territory with Smilodon.

The American cheetah lived on the prairies of North America. Its body plan resembled the modern cheetah’s and it was built for speed, but researchers aren’t sure if it was actually closely related to the modern cheetah. It may be more closely related to the cougar. It was a little larger and heavier than a modern cheetah. Either way, it’s probably the reason why pronghorn antelopes are so fast. They can run over 55 miles per hour or 88 km per hour, much faster than gray wolves and cougars, their current predators. The American cheetah died out around 12,000 years ago.

There are a lot of saber-toothed cats known to science, all related to Smilodon. But there are other animals with similar teeth that are unrelated to the saber-toothed cats. Thylacosmilus atrox looked superficially like a saber-toothed cat. It lived in South America, with most fossils found in Argentina, and went extinct close to three million years ago, long before Smilodon appeared in South America. But Thylacosmilus wasn’t a feline at all. It wasn’t even slightly related to felines. In fact, it was a marsupial, sometimes called a pouched saber-tooth because marsupials keep their babies in pouches, like kangaroos and possums.

Thylacosmilus was about the same size as Megantereon or a modern jaguar. Its saber-like canines were bigger than Smilodon’s and had roots so deep they were practically pressed up against the braincase. But it had something no saber-toothed cat had. Its lower jaw had a pair of bony downward projections called flanges. Think of it as a chin that went horribly wrong. The chin bones pointed downward at the same angle that the fangs pointed downward, and apparently protected them. Researchers aren’t sure if the fangs were actually inside the mouth or just pressed up against the outside of the chin.

Like Smilodon and its relatives, Thylacosmilus had immensely powerful forelegs that it used to grapple prey. But its jaws were weak. Smilodon’s jaws were much weaker than a big cat’s, but Thylacosmilus literally couldn’t outbite a domestic cat. Researchers think it grappled and subdued its prey with its forelegs, then delivered a precision bite with its fangs that severed the animal’s windpipe or major neck arteries. To do this, it didn’t need a strong bite, it needed strong neck muscles, and that’s exactly what it had.

Kolponomos was another saber-toothed animal, totally unlike Smilodon except for its teeth and powerful neck muscles. It’s related to bears, but that branch of the bear family also gave rise to pinnipeds like seals. Kolponomos lived around 20 million years ago along the Pacific coast and used its fangs not to bite the necks of its prey, but to pry shellfish off of rocks. Its snout was narrow and sloped downward, but we don’t have a complete skeleton so we don’t know how big it was or what it really looked like, but it probably resembled a buff sea otter with big fangs more than a seal or bear.

Clearly, saber teeth have evolved multiple times in different types of animals to serve different purposes. They’re not a recent development, either. 250 million years ago, just before dinosaurs evolved and took over the world. An animal called a gorgonopsid, or gorgon for short, lived in what is now Africa and Eurasia. Not a whole lot was known about it until 1998 when a very nearly complete skeleton was discovered in South Africa.

Complete skeletons are almost never found in the fossil record. Dinosaur and other animal skeletons displayed in museums are usually assembled from different individual animals. Sometimes a particular bone has never been found at all so scientists have to make an educated guess. But this gorgon looked like it had died and just flopped over. Nothing ate parts of it, nothing scattered its bones after it decayed. There it was, just waiting for the paleo team to find it.

Gorgon wasn’t a mammal. It wasn’t exactly a reptile either. It was a precursor to mammals, a reptilian creature with mammalian characteristics. It resembled a lion crossed with a monitor lizard, although researchers aren’t sure if it had actual fur or both bristles and scales. It was big—some ten feet or 3 meters long with saber-tooth fangs nearly 5” or 12 centimeters long. Reptiles living today have legs that stick out from the sides of their bodies, so when they walk their bellies are very close to the ground, but gorgon’s stance was different. Its walk probably resembled what’s called the “high walk” of crocodilians, where the gator lifts its body and tail off the ground entirely to walk more easily and quickly on land. Researchers think gorgon hunted by ambushing its prey and delivering a massive bite, then retreating to wait for the injured animal to weaken. This is similar to how komodo dragons hunt.

Gorgon died off in the Permo-Triassic extinction event 250 million years ago. Everyone knows about the Cretaceous-Paleogene extinction that ended the rule of the dinosaurs, but the Permo-Triassic extinction was even worse. More than 95% of all marine animals died out, and some 70% of land animals. Even a lot of insects went extinct, and some evidence suggests that a lot of plants went extinct too. Scientists don’t know what caused the extinctions, but it might have been a meteor strike like the one generally accepted to have caused the Cretaceous-Paleogene event. Whatever happened, it hit marine life hard because the oceans became extremely acidic due to increased CO2 levels in the air and the increased temperature at the ocean’s surface in many areas—104o F or 40o C. It took millions of years for the oceans to recover.

So far all the animals in this episode are extinct. While a lot of living animals have fangs of one kind or another, there don’t seem to be any that use their fangs the way saber-toothed cats did. But I don’t want to leave you after saying, “Yeah, something happened and everything DIED,” so I’ll finish up by talking about the sabertooth fish, of the family Evermannellidae. It’s alive and it’s wonderfully creepy.

The sabertooth fish lives in the depths of tropical and subtropical waters. It has tubular eyes that point upwards so it can see its prey, mostly squid, silhouetted against the far-off surface. It’s grayish-brown in color with a greenish iridescence. Its fins are brown. It has smooth skin without scales and a big mouth that can open extremely wide, which is good because the sabertooth fish can swallow prey that’s actually bigger than it is. Its stomach distends to hold whatever can fit down its gullet. This sounds terrifying, especially when you look at its teeth, but keep in mind that it’s only about seven inches long, or 18 cm. It has two pairs of curved fangs, one in the upper jaw, one in the lower, with smaller teeth in the back of its mouth. If you’ve ever tried to catch a living squid with just your mouth—and I really hope you have not—you’ll probably have noticed that it’s hard to keep the squid from slithering away. Wouldn’t some saber teeth help with that? The sabertooth fish thinks so.

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 iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

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Episode 033: Dunkleosteus, Helicoprion, and their weird-toothed friends

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This week we’ll learn about some terrifying extinct fish, the armored dunkleosteus and the spiral-toothed helicoprion, plus a few friends of theirs who could TEAR YOU UP.

Dunkleosteus did not even need teeth:

Helicoprion had teeth like crazy in a buzzsaw-like tooth whorl:

Helicoprion’s living relatives, chimaeras (or ghost sharks) are a lot less impressive than they sound:

Helicoprion probably looked something like this:

But helicoprion has been described in all sorts of wacky ways over the years:

So what are the odds this rendition of edestus is correct? hmm

Show transcript:

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

This week we’ve got a listener suggestion! Will B. suggested placoderms, which were armored fish that lived hundreds of millions of years ago. He especially recommended Dunkleosteus. I looked it up and went, “Oh holy crap,” so you bet we’re going to learn about it today. I’m also pairing that terrifying fish with a really weird shark relation called Helicoprion. And we might even take a look at a few other fishes while we’re at it. Creepy extinct fish for everyone! Oh, and Will asked that I include more metric conversions. [heavy sigh] okay I guess

If you had happened to live around 350 million years ago when Dunkleosteus was alive, you would be a fish. Well, you would probably be a fish. I don’t know for sure. That was during the Late Devonian period, and the Devonian is remembered as the “age of fish” by undergraduate geology and palaeo students everywhere. While land plants were evolving like crazy, developing true roots and seeds, fish were even crazier. Ray-finned fish evolved during the Devonian and so did lobe-finned fish like coelacanths. The first amphibious critters developed in shallow lakes and started to spend time on land, and in the ocean there were early sharks, lots of trilobites, and a whole lot of armored fish. Including, eventually, dunkleosteus.

Dunkleosteus terrelli was the biggest species of placoderm. It probably grew over 30 feet long OR TEN METERS, WILL, which made it bigger than a great white shark. But dunkleosteus didn’t have teeth. And before you think, oh, it must have been a filter feeder or something, oh no. It didn’t need teeth. Instead it had bony plates like a gigantic beak. It could open and close its jaws incredibly fast—something like one 50th of a second—and could bite through armor and bone no problem. One article referred to its jaws as sheet-metal cutters. Scientists think its bite was as powerful as that of a T rex, although it didn’t quite match that of megalodon, but since T rex and megalodon both lived many millions of years later than Dunkleosteus, it’s useless to speculate who would win in a fight. But my money’s on Dunkleosteus.

Dunkleosteus wasn’t a fast swimmer. Its head was covered in heavy armor that probably served two main purposes. One, the armor plates gave its massive jaw muscles something substantial to attach to, and two, it kept its head safe from the bites of other placoderms. That’s right. Dunkleosteus was a cannibal.

We actually don’t know exactly how long Dunkleosteus was or what most of its body looked like. The only fossils we’ve found were of the head armor. We do have complete fossils and body impressions of other, much smaller placoderms, so since all placoderms seemed to have the same body plan we can make good guesses as to what Dunkleosteus looked like.

One surprising thing we do have associated with Dunkleosteus fossils are some remains of its meals. These are called fish boluses, and they’re basically just wads of partially-digested pieces of fish that either get horked up by whatever ate them or pass through the digestive tract without being fully digested. From the fish boluses, we know that Dunkleosteus probably preferred the soft parts of its prey and didn’t digest bones very well.

In 2013, a fossil fish over 400 million years old was described that combines features of a placoderm skeleton with the jaw structure that most bony fishes and four-footed animals share. Some other early bony fishes discovered recently also show some features of placoderm skeletons. What does that mean? Well, until these discoveries, researchers had thought bony fishes weren’t very closely related to placoderms. Now it looks like they were. And that means that placoderm jaws, those fearsome cutting machines, were actually the basis of our own jaws and those of most animals alive today. Only, in our case they’re no longer designed to shear through armor and bone. Maybe through Nutter Butters and ham sandwiches instead.

So what happened to dunkleosteus? Around 375 million years ago something happened in the oceans—not precisely an extinction event, but from our perspective it looks like one. Even without human help species do go extinct naturally every so often, and when that happens other species evolve to fill their ecological niches. But during the late Devonian, when species went extinct in the ocean… nothing took their place.

We don’t know what exactly was going on, but researchers have theories. One suggestion is that, since sea levels were rising, marine environments that were once separated by land got joined together. Species that had evolved in one area suddenly had access to a much bigger area. They acted like invasive species do today, driving native species to extinction and breeding prolifically. They kept new species from developing, and caused a breakdown in the biodiversity of their new territories. This only happened in the oceans, not on land, which adds credence to the theory.

It took a long, long time for the oceans to fully recover. For example, coral reefs disappeared from the fossil record for 100 million years as corals almost died out completely. But the animals that had already started evolving to take advantage of life on land survived and thrived—and that led to us, eventually. Us and our little unarmored jaws.

From Dunkleosteus and its sheet-metal cutter beak let’s go to another fish that looked like a shark but had teeth that are so bizarre I can’t even understand it. Helicoprion and its tooth whorl have baffled scientists for over a century.

The various species of Helicoprion lived around 290 million years ago. Like sharks, only its teeth are bony. The rest of its skeleton is made of cartilage, which doesn’t preserve very well.

So what’s a tooth whorl? It resembles a spiral shell, like a snail’s, only made of teeth. I’m not even making this up. Originally people actually thought they were some kind of weird spiky ammonite shell, in fact. Then someone pointed out that they were made of teeth, but no one could figure out what earthly use a circular saw would be if you were a fish and just wanted to eat other fish. Where would you even keep a circular saw of teeth?

Various suggestions included putting the tooth whorl at the very end of the lower jaw, just sort of stuck out there doing nothing; putting the tooth whorl way in the back of the throat where I guess it would cut up fish as they went down; on the snout, on the back, or even on the tail, which are not places where teeth typically do much good. Originally researchers thought the tooth whorl was probably a defensive trait, but now it’s accepted that it was used the way the rest of us use our teeth, which is to eat things with.

The smallest teeth in a tooth whorl are on the inside curls and the biggest are on the outside. Eventually researchers realized the small teeth were from when the individual was a baby fish and had little teeth. Like sharks, helicoprion kept growing teeth throughout its life. Unlike sharks, it didn’t lose its old teeth when the new ones grew in. The older, smaller teeth were just pushed forward along the curve of the whorl and eventually were buried within the animal’s jaw, with only the biggest, newest teeth actually being used.

In 1950 a crushed tooth whorl was found with some cranial cartilage, so scientists knew that the whorl was associated with the head and wasn’t, for instance, on the dorsal fin. That fossil was found in Idaho and consisted of 117 teeth. The whorl was 23 cm in diameter, or about 9 inches across, although slightly larger ones have been found. In 2011 the fossil was examined with a state-of-the-art CT scanner and a 3D computer model generated of the animal’s skull.

Researchers think they have a pretty good idea of what a living helicoprion’s head and jaws looked like. The tooth whorl was fused with and extended the full length of the lower jaw. It grew inside the mouth roughly where the tongue would be if it had a tongue, which it did not. Helicoprion didn’t have teeth in its upper jaw, so the tooth whorl acted less like chompers than like a meat slicing machine. When it closed its mouth, the tooth whorl was pushed back a little and would therefore slice through any soft-bodied prey in the mouth and also force its prey deeper into its mouth. Helicoprion probably ate small fish, cephalopods, and other soft-bodied organisms.

Since we don’t have any fossils or impressions of helicoprion’s body, we don’t know for sure what it looked like, but researchers estimate it probably grew to around 13 feet or 4 meters, but may have possibly exceeded 24 feet or 7.5 meters.

For a long time researchers thought helicoprion was a shark, but it’s now classified as a type of chimaera, which are small weird-looking shark-like fish known also as ghost sharks, spookfish, ratfish, and rabbit fish. I’m going to call them ghost sharks because that’s awesome. They’re not that closely related to sharks although they do have cartilaginous skeletons, and most species like the ocean depths. Ghost sharks have been spotted at depths of 8,500 feet, or 2,600 meters. The longest any species grows is around 5 feet, or 150 cm. Unlike helicoprion, they don’t have exciting teeth. They don’t really have teeth at all, just three pairs of tooth plates that grind together. Some species have a venomous spine in front of the dorsal fin.

While we’re talking about shark-like fish with weird teeth, let’s discuss Edestus, a genus of shark-like fish with weird teeth that lived around 300 million years ago, around the same time as dunkleosteus. It was related to helicoprion but it didn’t have a tooth whorl. Instead it had one curved bracket of teeth on the lower jaw and one on the upper jaw that meshed together like pinking shears. You know what pinking shears are even if you don’t recognize the name. Pinking shears are scissors that have a zigzag pattern instead of a straight edge, so you can cut a zigzag into cloth but not paper because do not dare use my pinking shears for anything but cloth. It dulls them.

Anyway, like helicoprion Edestus didn’t shed its teeth but it did grow new ones throughout its life, so like helicoprion it had a bunch of teeth it no longer needed. In Edestus’s case we don’t have any bits of skull or jaw cartilage to give us a clue as to how its teeth sat in its jaw. A lot of scientific art of Edestus shows a shark with a pointy mouth, where the upper point curves upward and the lower point curves downward with teeth sticking out from the middle. Sort of like an open zipper, if the zipper part was teeth and the non-zipper side was a shark’s mouth. To me that looks sort of ridiculous, and I suspect in reality Edestus looked a lot more like helicoprion. The downward and upward curved parts of the tooth arc was probably buried within its jaw, not sticking out. But that’s just a guess based on about 30 minutes of research.

Researchers estimate that the largest species of Edestus probably grew to about 20 feet long, or 6 meters. No one’s sure how or what it ate, but one suggestion is that if its teeth did project out of its mouth, it might have slashed at prey with its teeth sort of like a swordfish slashes prey with its elongated beak. Hopefully scientists will find a well preserved specimen one day that will give us some clues as to what Edestus looked like, at which point I bet the drawings we have now will look as silly as helicoprion with a tooth whorl perched on its nose.

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 iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

Thanks for listening!

Episode 032: Some New Zealand birds

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This week’s episode is about several New Zealand birds, from the still-living kiwi to the mmmmmaybe extinct moa! Note: I’m going to start putting a full transcript of each episode in the show notes for those who would like to know what words I’m mispronouncing and for those who may have hearing issues. Transcripts will be below the pictures.

A kiwi:

Superman has fought everything.

The controversial blurry “moa” picture taken by Freaney. Probably not a moa.

Show transcript:

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

Before we get started, apologies for my voice. About the time I finally got over the cough I picked up at WorldCon in Finland, I went to DragonCon in Atlanta and got a big juicy cold. Hopefully I don’t sound too gross. My traveling for the year is over so I’m looking forward to having time to really dig into some fun topics for the podcast. In particular, I’m going to be covering some of the creepier strange animals in October, because Halloween is the best. And yes, Bigfoot is going to make an appearance.

This week’s episode is about some amazing birds from New Zealand. We learned about the takahe way back in episode seven, a big silly-looking flightless bird that was once thought extinct until its rediscovery in the middle of the last century. This week we’ll look at some other birds, some of them happily alive, some that are definitely extinct. At least, we’re pretty sure they are.

New Zealand wasn’t settled by humans until the late 13th century, only about 750 years ago. That’s mind-blowing until you take a look at a globe. New Zealand isn’t just a hop skip and jump away from Australia, it’s 900 miles away over open ocean. It’s 600 miles away from the Pacific Islands. That’s a long, long trip to make in a small boat, especially when you’re not sure if there’s any land out that way. But sometime between the years 1250 to 1300, people from eastern Polynesia discovered this new land. They liked it and stayed, and their descendants are now known as the Maori.

I know we’ve been talking about tectonic plates in a number of episodes recently. I haven’t done it on purpose—it’s just part of learning how and why different animals developed in different places. It’s definitely relevant when it comes to New Zealand.

New Zealand is just a little part of an otherwise submerged continent called Zealandia, or sometimes Tasmantis, which I actually prefer. Tasmantis. If Zealandia weren’t mostly under the ocean, it would be about half the size of Australia. Around 90 million years ago Zealandia, Australia, and Antarctica were all part of the supercontinent Gondwana. As Gondwana broke up, Zealandia separated from Antarctica and Australia around 80 million years ago, then slowly sank into the ocean.

After Zealandia separated from Gondwana, a cataclysmic event, probably a humongous meteor strike, led to the extinction of some 85% of the animals on earth. In most of the world, mammals began to evolve like crazy to fill the vacant ecological niches after the dinosaurs died off. But Zealandia didn’t have very many mammals to start with, and by 25 million years ago it was mostly underwater anyway except for the peaks of New Zealand, which were being pushed up slowly by tectonic forces—a process that’s still ongoing.

When travelers from Polynesia first landed on New Zealand, the only mammals on the islands were three species of bat. But there were birds in abundance, from enormous moas and eagles to tiny kiwi. Almost every ecological niche was filled by a bird.

Europeans first visited New Zealand in 1642. It didn’t go well and no one came back until 1769, and after that things got messy and lots of people died from war and introduced diseases. Around the mid-19th century Europeans started moving to New Zealand. Between them, the Maori, and introduced mammals like rats and dogs, a whole lot of birds went extinct.

I just want you to know that it took me hours and hours and hours to research all that stuff about Zealandia. Hopefully I got it right. I’m ready to talk about birds now.

Let’s start with a bird that is so unique to New Zealand that you’ll sometimes hear people call New Zealanders kiwis. There are five species of kiwi, all of them rare and protected. They’re round brown poofs of birds with long legs and long bills, and they eat worms, insects, seeds, fruit, frogs, and other things like that. They prefer to live in forests and usually mate for life, and can live for 50 years.

The kiwi has a lot of unusual characteristics. It’s flightless but has wings less than an inch long hidden under its feathers. Each wing has a tiny claw at its tip that doesn’t seem to have a use. The kiwi has no tail. Unlike every other bird out there, its nostrils are at the tip of its bill. The kiwi has a good sense of smell and may detect worms and other underground prey by smell, which should make you pause and wonder what earthworms smell like. The kiwi also has sensory pits at the tip of its bill that helps it detect vibrations, though, so it’s possible its good sense of smell is less important than researchers previously thought. When a kiwi detects its prey, it stabs its bill into the ground to catch it, which frequently leads to the kiwi later having to snort dirt out of its nostrils. Evolution does what it can, folks, but it’s not perfect.

Since it can’t fly and doesn’t need flight feathers, the kiwi’s feathers are hair-like and downy. But most curious of all is its egg. The kiwi is about the size of a chicken, but its egg is six times the size of a chicken egg and can weigh an entire pound. It’s so big that the female can’t even eat the last few days before she lays the egg. There’s no room in her body for food.

After the female lays her egg, the male incubates it. That huge egg has a huge yolk to feed the baby inside, so when the baby kiwi hatches, it’s ready to go. After a few days it leaves the nest and starts foraging, usually with its dad alongside for the first few weeks. It takes several years for it to grow to adult size.

The kiwi is territorial and will fight other kiwis that stray into its territory. Only its mate and its own offspring are allowed in its territory. It has powerful legs with claws that can inflict quite a bit of damage, and it can run faster than a human.

Scientists used to think the kiwi was closely related to moas, which we’ll talk about in a minute, but DNA studies have determined that its closest relative is the extinct elephant bird of Madagascar—and the elephant bird is the topic for a future episode.

The Maori describe a huge black swan called a Pouwa that lived in the Chatham Islands, but it had already gone extinct by the time Europeans arrived in the area in the late 1700s. Until recently researchers thought it was just the Australian black swan, either a population that lived in New Zealand or the occasional individual that flies across the Tasman Sea. Australian black swans were introduced to New Zealand in the 1860s.

But a recent study of DNA from fossilized swan remains from New Zealand show that it wasn’t the same bird as the Australian black swan but a related species. Around one or two million years ago Australian black swans lived in New Zealand and evolved into a separate species, heavier than the Australian birds with longer legs and shorter wings. It might have been a poor or reluctant flier and might have been on its way to evolving into flightlessness before it was eaten into extinction by the Maori.

The big name in extinct birds of New Zealand is the moa. Nine species of moa are recognized today, although in the past researchers thought there were a lot more. It turns out that female moas of some species were much larger than the males, so much so that scientists once thought they were looking at two different species. Moas were big flightless birds that in shape resembled big flightless birds from other parts of the world, known as ratites, which includes ostriches. Until DNA testing most researchers thought moas were closely related to the ratites of Australia, emus and cassowaries. But no, they are most closely related to a group of birds from Mexico, Central America, and South America collectively called tinamous. Tinamous are a type of ratite, but they can fly. They’re all fairly small and somewhat resemble quail and other game birds that spend a lot of time foraging on the ground.

Moas, however, are big. They are really big. Originally scientists mounted their skeletons so that the neck stuck more or less straight up, but now we know that they held their necks more like ostriches, with a gentle S-shaped curve. Even so, females of the biggest species, the South Island Giant Moa, stood around six and a half feet high at the back. That doesn’t even count the neck. With the neck outstretched, a big female moa could probably reach leaves twelve feet off the ground.

All moas were plant-eaters. Some ate leaves and fruit, others were adapted to digest tougher plant material like twigs, moss, and bark. Unlike other flightless birds, they didn’t have wings at all, not even for display, not even vestigial wings. They just flat-out didn’t have forelimbs. They did have strong legs although they probably couldn’t run very fast, unlike other flightless birds like ostriches. After all, moas didn’t need to run to escape predators. They only had one predator, and that was one they couldn’t outrun: Haast’s eagle.

Haast’s was the biggest eagle that ever lived, although its wings were comparatively short—only around 10 feet wide for big females, closer to 8 ½ feet wide for big males and more average-sized females. Since much of its hunting range was forested, its shorter wings probably helped it maneuver. It had a long tail too. But it had enormous talons with claws over four inches long, and its bill was similarly big. In fact, its talons were so big that its scientific name, Harpagornis moorei, means Moore’s grappling hook bird.

The Haast’s eagle’s prey was the moa, and when moas went extinct after overhunting, the Haast’s eagle went extinct soon after since it just didn’t have anything to eat. It did apparently try to adapt its hunting habits, though. Maori legends tell of the Pouakai, an enormous bird that would sometimes kill humans.

It’s pretty certain that Haast’s eagle is extinct. If it was still around, ranchers would spot it picking off sheep and calves. But the moa is something else. Moa sightings pop up pretty frequently in remote areas of New Zealand.

One of the smallest species of moa, Megalapteryx, also called the upland moa, may have survived on the south island until the mid-19th century. The upland moa was three or four feet tall including the head and neck, and was completely covered with feathers except for its bill and feet, since it lived in the mountainous areas of New Zealand’s south island where the climate was cool. It laid one or two blue-green eggs a year and the male took care of the babies.

Its accepted date of extinction is around the year 1500, but there have been numerous sightings since then. In 1880, Alice McKenzie, who was then seven years old, saw a three-foot-tall bird with blue feathers, dark green scaled legs, and three claws on each foot. She ran to get her father, but when they returned the bird had gone, although it had left big tracks in the sandy soil. She saw the same bird again in 1889.

The problem with this sighting is that the upland moa had feathered legs, and as far as we know no moas had blue plumage. We have plenty of upland moa feathers, which are grey, black and white. We even have mummified upland moa remains. Not only did Alice describe her bird as blue, she specifically noted it was the blue of a pukeko, which has vibrant plumage that varies from navy blue to violet. This wasn’t a grayish-blue bird. Alice herself thought, later in life, that she might have seen a takahe, which is also blue, but after the takahe was rediscovered she went to view some and was disappointed. They have red legs and she knew her bird’s legs were green.

But that’s not the only sighting. In addition to the sporadic accounts of big birds seen in the distance, in 1993 three men hiking in the Craigieburn Range saw what they described as a red-brown and gray moa some six feet high, including its neck. It ran off when it saw them, but one of the men, Paddy Freaney, ran after it and managed to get a photograph. He also got a few pictures of its footprints where it had stepped in a stream and then on a rock.

The picture is frustrating, to say the least. It’s so out of focus that it could be anything. However, I agree with one of the experts who have examined the photo, palaeoecologist Richard Holdaway, who says the figure’s neck is too thick for a moa. He thinks the picture is probably of a red deer. As far as I can find, Freaney’s photos of the footprints haven’t been released.

In 2007, a pair of cryptozoologists searching for moas in the hill country of the North Island spotted 35 footprints and what appeared to be a nest that they claimed were made by a group of moas, possibly a lesser moa. But considering that the pair of cryptozoologists are Rex and Heather Gilroy, who are notorious for being secretive, vague in their claims of evidence, and somewhat paranoid about their findings, I don’t expect them to show up with a live moa anytime soon. No other moa sightings or even rumors of moas living in the area have ever been uncovered.

It’s easy to dismiss this account, and the others, as wishful thinking, misidentification, and in some cases maybe outright hoaxes. Australian emus are raised in some areas of New Zealand and sometimes escape from captivity, too, which confuses the issue, since emus are big flightless birds that could easily be mistaken for moas at a distance. But there is something that makes me hopeful that the moa might still be around, especially one of the smaller species.

New Zealand’s south island is much less populated than its north island. Alice McKenzie’s sighting in 1880 was on her family’s farm near Milford Sound, which is now part of Fiordland National Park. This is a big nature reserve in the southwest corner of the south island, with rugged terrain and very few tracks passable to even offroad vehicles. The park includes the Murchison Mountains, which is where the takahe was rediscovered in 1948 after being thought extinct. So it’s entirely possible that a small species of moa might be hiding in the area. Maybe one day someone will get a really good picture—or better yet, a hiker or park ranger might come across a newly dead moa carcass and can bring it back for study.

We do have some subfossil moa remains that aren’t just skeletons and feathers. Dessicated body parts turn up occasionally, which has helped with DNA testing and our knowledge of what the living birds looked like. The moa is a good candidate for de-extinction by genetic cloning, and it would be really neat to have moas for sure running around in New Zealand again, so scientists can get right on that as far as I’m concerned.

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 iTunes or whatever platform you listen on. We also have a Pattreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

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Episode 026: Humans Part Two

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Part two of our humans episode is about a couple of our more distant cousins, the Flores little people (Homo floresiensis) and Homo naledi, with side trips to think about Rumpelstiltskin, trolls, and the Ebu gogo.

Homo floresiensis skull compared to a human skull. We are bigheaded monsters in comparison. Also, we got chins.

Homo naledi’s skull. I stole that picture from Wits University homepage because I really liked the quote and it turns out it’s too small really to read. Oh well.

Some of our cousins. Homo erectus in the middle is our direct ancestor. So is Lucy, an Australopithecus, although she lived much longer ago.

Show transcript

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

This week is part two of our humans episode. Last week we learned how modern humans evolved and about two of our close cousins, Neandertals and Denisovans. This week, we’re going to walk on the weirder side of the hominin world.

Before we get started, this episode should go live on July 31, 2017, one week before I fly to Helsinki, Finland for WorldCon 75! Don’t worry, I’ve got episodes scheduled to run normally until I get home. If you’re going to be in Finland between August 8 and August 17, let me know so we can meet up. On Thursday, August 10 and 4pm I’ll be on a panel in room 207 about how to start a podcast, so check it out if you’re attending the convention. I’ll also be in Oslo during the day on August 7 and have two birding trips planned with lunch in between, and I’d love you to join me if you’re in Oslo that day too. Then, two weeks after I return from Finland, I’ll be attending DragonCon over Labor Day weekend. blah blah blah this is old news

Now, let’s learn about some of our stranger distant cousins!

In 2003, a team of archaeologists, some from Australia and some from Indonesia, were in Indonesia to look for evidence of prehistoric human settlement. They were hoping to learn more about when humans first migrated from Asia to Australia. One of the places they searched was Liang Bua cave on the island of Flores. They found hominin remains all right, but they were odd.

The first skeleton they discovered was remarkably small, only a bit more than three and a half feet tall [106 cm] although it wasn’t a child’s skeleton. That skeleton was mostly complete, including the skull, and appears to be that of a woman around 30 years old. She’s been nicknamed the Little Lady of Flores, or just Flo to her friends. Officially, she’s LB1, the type specimen for a new species of hominin, Homo floresiensis.

But until very recently, that statement was super controversial. In fact, there’s hardly anything about the Flores remains that aren’t controversial.

At first researchers thought the remains were not very old, maybe only twelve or thirteen thousand years old, or 18,000 at the most. Stone tools were found in the same sediment layer where Flo was discovered, as were animal bones. The tools were small, clearly intended for hands about the size of Flo’s, which argued right off the bat that she was part of a small-statured species and wasn’t an aberrant individual.

The following year, 2004, the team returned to the cave and found more skeletal remains, none very complete, but they were all about Flo’s size. Researchers theorized that the people had evolved from a population of Homo erectus that had arrived on the island more than three quarters of a million years before, and that they had become smaller as a type of island dwarfism. A volcanic eruption 12,000 before had likely killed them all off, along with the pygmy elephants they hunted.

But as more research was conducted, the date of the skeletons kept getting pushed back: from 18,000 years old to 95,000 years old to 150,000 years old to 190,000 years old. Dating remains in the cave is difficult, because it’s been subject to flooding and partial flooding over the centuries. Currently, the skeletal remains are thought to date to 60,000 years ago and the stone tools to around 50,000 years ago.

When news of the finds was released, the press response was enthusiastic, to say the least. The skeletons were dubbed Hobbits for their small size, which made the Tolkien estate’s head explode, and practically every few weeks it seems there was another article about whether there were small people still living quietly on the island of Flores, yet to be discovered.

And, of course, there were lots of indignant scientists who were apparently personally angry that the skeletons were considered a new species of hominin instead of regular old Homo sapiens. Part of the issue was that only one skull has ever been found. It’s definitely small, and the other skeletal remains are all correspondingly small, and the stone tools are all correspondingly small, and the skull shows a number of important differences from that of a normal human. But that doesn’t necessarily mean it’s not a subspecies of Homo sapiens, and of course that needs to be investigated. But some of the arguments got surprisingly ugly. There were even accusations that the entire find was faked. One person even suggested that the skull’s teeth showed evidence of modern dental work.

Amid all this, two unfortunate things happened. First, in December 2004 an Indonesian paleoanthropologist named Teuku Jacob removed almost all the bones from Jakarta’s National Research Centre of Archaeology for his own personal study for three months. When he returned them, two leg bones were missing, two jaw bones were badly damaged, and a pelvis was smashed. Then, not long after, Indonesia closed access to Liang Bua cave without explanation, although the archeological community suspected it was due to Jacob’s influence, and didn’t reopen it until 2007 after Jacob died.

It’s important to note that Jacob was a proponent of the theory that the remains found in Liang Bua cave were microcephalic individuals of the prehistoric local population, not a new hominin species at all. He also had a history of keeping Indonesian fossils from being studied unless he specifically approved of the research.

At any rate, since then, repeated studies of the LB1 skull have suggested that Homo floresiensis is a separate species of hominin and not a Homo sapiens with evidence of pathology, whether microcephaly or another disease, or a population with a genetic abnormality. There’s still plenty of research needed, of course, and hopefully some more skulls will be found. But it seems clear that Homo floresiensis isn’t just a weird subspecies of Homo sapiens.

One of the more common theories in the last few years was that Homo floresiensis was descended from Homo erectus, although Homo erectus was a lot bigger and more human-like than the Flores little people. But results of a study released just a few months ago show that Homo floresiensis shared a common ancestor with Homo habilis around 1.75 million years ago. Homo floresiensis may have evolved before migrating out of Africa, or their ancestor migrated and evolved into Homo floresiensis. Either way, they spread as far as Indonesia before dying out around 50,000 years ago.

Other hominin remains have since been found on the island. Part of a jaw and teeth were found at Mata Menge on the island of Flores, some 50 miles away from the cave. It’s around 700,000 years old and is a bit smaller than the same bones in the later skeletons. Researchers think it’s an older form of Homo floresiensis.

Possibly not coincidentally, modern humans arrived on the island about 50,000 years ago, maybe earlier, bringing with them the arts of fire, painting, making jewelry from animal bones, and killing all of our genetic cousins.

We don’t know if humans deliberately killed the Homo floresiensis people or if they just outcompeted them. It does seem pretty certain that the two hominin species coexisted on the island for at least a while. It’s even possible that knowledge of the strange small people of the island has persisted in folk tales told by the Nage people of Flores. Stories about the ebu gogo have been documented for centuries. They were supposed to be little hairy people around three feet tall [one meter], with broad faces and big mouths. They were fast runners with their own language and would eat anything, frequently swallowing it whole. In some stories they sometimes kidnapped human children to make the children teach them how to cook, although the children always outwitted the ebu gogo.

Supposedly, at some point, tired of their children being kidnapped and their food being stolen, villagers gave the ebu gogo palm fibers so they could make clothes. The ebu gogo took the fibers to their cave, and the villagers threw a torch in after them. The fiber went up in flames and killed all of the ebu gogo.

Until the discovery of Homo floresiensis, anthropologists assumed the stories were about macaque monkeys. But there’s a genuine possibility that the ebu gogo tales are memories of Homo floresiensis. It’s not just cryptozoologists and bigfoot enthusiasts making the connection between the ebu gogo and Homo floresiensis. Articles and editorials have appeared in journals such as Nature, Scientific American, and Anthropology Today. At least, they did back when archeologists thought Flo was only about 12,000 years old.

But we still don’t know for certain when Homo floresiensis went extinct. There may be remains that are much more recent than 50,000 years ago. Locals mostly say there are no ebu gogo left but that they were still around about a century ago. I don’t know how long historical elements can persist in an oral tradition without becoming distorted. As we discussed in episode 17, about Thunderbird, oral history is easily lost if the culture is disrupted by invasion, disease, war, or other major episodes. But some stories are tougher than others, and those that are less history and more entertainment—although they may contain warnings too—can be very, very old.

Researchers have traced some traditional folktales, like Rumpelstiltskin, back some 4,000 or even 6,000 years, although not without controversy. But while Rumpelstiltskin is usually described as a small person, no one’s suggesting that story is about real events. It’s the juxtaposition of the Flores discoveries of small skeletons and the oral tradition or small people living on the island that got researchers excited. And as it happens, there is an oral tradition many miles and many cultures away from Flores that might be something similar.

Old Norse stories about trolls date back thousands of years. The trolls vary in appearance and sometimes have a lot of overlap with other monsters, but generally are described as big and strong, not very smart, often placid unless provoked, and usually evil, or at least godless. Sometimes they capture humans who outwit them to escape. In one story, a man named Esbern Snare wanted to marry a woman, but her father would only agree to the marriage if Esbern would build a church. Esbern struck a deal with a troll, who said he would build the church—on one condition. If Esbern couldn’t guess the troll’s name by the time the church was built, the troll would demand as his payment Esbern’s heart and eyes.

Esbern agreed, but he failed to trick the troll into telling him his name. On the final day, in despair Esbern threw himself down on the bank of a river, where he overheard the troll’s wife singing to her baby:

“Hush, hush, baby mine,

Tomorrow comes Finn, father thine,

To bring you Esbern’s heart and eyes

To play with, so now hush your cries.”

Esbern rushed back to the church and greeted Finn the troll by name. In some version of the story, Finn is so furious that he leaves the church incomplete in some way, usually a missing pillar. For those of you who aren’t familiar with the Rumpelstiltskin story, that’s a variant. Oh, and Esbern Snare was a real person who lived in the twelfth century, although I’m pretty sure he didn’t actually strike any deals with trolls.

But I do wonder if some elements of troll folklore might be derived from memories of Neandertal people. I’m not the first to suggest this, although it is a pretty fringey theory. And in the end, we just don’t have any way to know. But it is interesting to think about.

As you may remember from part one of the humans episode, Homo sapiens evolved roughly 200,000 years ago. But around the same time, or a little earlier, another cousin in our family tree was living in southern Africa. Remains of Homo naledi were only discovered in 2013 by some cavers. Partial skeletons from at least 15 individuals were recovered in one field season, but due to narrow cave passages, the field work had to be done by people of small stature who weren’t claustrophobic, mostly women.

Homo naledi is a mixture of primitive and advanced features. Primitive in this case means more like our ape ancestors, and advanced means more like modern humans. Homo naledi had long legs and feet that looked just like ours, but also had a small brain and fingers that are much more curved than ours—not characteristics that would look out of place a few million years ago, but surprising to discover in our family tree at about the same time that modern humans were evolving.

On the other hand (with curved fingers), evolution doesn’t have an end goal. Homo sapiens is not the pinnacle of creation to which all other living beings aspire. We’re just another animal, just another great ape. If Homo naledi was successful in their environment with a small brain, that’s all that matters from an evolutionary standpoint.

There are lots of remains left in the cave, so many in fact that some researchers are convinced they didn’t get there by accident. It’s possible that the cave was used as a burial pit, maybe even over the course of centuries. Bodies may have been dropped in a deep shaft and were then moved by periodic flooding to the remote chamber where they were found, or they may have been carried to the cave depths and left there.

Homo naledi wasn’t a direct ancestor of Homo sapiens, but they were definitely a kind of human—no matter how small their brains may have been.

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. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 025: Humans Part I (Neanderthals and Denisovans)

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This week is our first two-parter ever! I don’t intend to do that often but there was just too much to go over for one episode. This week we’ll talk about humans: where we come from, how we evolved, and who our closest cousins are–Neanderthals and Denisovans.

Some young humans. Humans can do many surprising things, including surfing, making stained glass, and repairing helicopters. Most humans like the color blue and enjoy listening to music.

The bracelet found with Denisovan bones in a Siberian cave. Humans didn’t make or wear this lovely thing, Denisovan people did.

Further reading:

How to Think Like a Neandertal by Thomas Wynn and Frederick L. Coolidge

Show transcript:

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

This will be our first two-part episode. There’s so much to cover with this topic that I decided to split it into two. This week we’re going to investigate an unusual family of great apes: both the living representative and their extinct relatives—and I don’t know why I’m saying “their extinct relatives,” because the great apes in question are known as Homo sapiens.

Humans tend to view ourselves as separate from the natural world. Some of us see ourselves as special, above other animals and better than them. Some of us see ourselves as despoilers of nature who can’t be trusted at all. But in reality, we’re neither angels nor devils. We’re animals too, and we fit neatly in the world because we evolved to live here, just like every other animal did too.

Humans have two major things going for us. First of all, we’re really smart. We’re only now learning the ways other animals show high intelligence, but even so, hands down we are the brightest apes in the circus. Our intelligence allows us to invent amazing things to make our lives more comfortable, like beds and shoes and medicine and umbrellas and podcasts. Unfortunately, our intelligence also lets us invent things that aren’t so nice, like bombs, because like our close cousins the chimpanzees, we can be real jerks.

But besides our intelligence, which is an obvious plus, we’ve got something very few other animals have: stamina, and the ability to shed heat efficiently, which makes us tireless hunters. In fact, that combined with our ability to make and use tools made early humans pretty much unstoppable.

Persistence hunting is only practiced by a few species of animal, like grey wolves, spotted hyenas, and humans. Humans aren’t especially fast runners compared to horses and deer and other prey animals, but we can just run on and on, sweating to cool ourselves, while our prey has to rest to cool down. One downside to this is that we can drive ourselves to heat exhaustion without realizing it, when conditions are just too hot to be constantly active.

I just looked this up, because I just realized I didn’t know if other female animals menstruate like human women. It turns out that female chimps do, along with a few other primates—and bats, for some reason. Solidarity with our bat girlfriends.

Actually, all placental mammals prepare a womb lining periodically, but when it turns out they don’t need it because they’re not going to have babies, they just reabsorb the material. Only a few species shed it, and even in humans we reabsorb most of it. Some researchers think we menstruate because it’s actually easier on the body to just dump the last of that unused stuff rather than spend extra energy absorbing it.

Now that we all know a few things about humans that we might not have known before, here’s a somewhat simplified overview of how humans evolved.

Humans and our ancestors are called hominins collectively. There were some apes 6 or 7 million years ago that were probably somewhat bipedal, and which are considered the earliest known hominins. We’re not sure which of the several species is our direct ancestor and which is our last shared ancestor with gorillas and chimpanzees.

Bipedalism is a defining trait of hominins. It took a long time to develop because there are a lot of skeletal and other changes needed to make it work effectively. By about 3 or 4 million years ago, the Australopithecines had evolved, and we know they walked upright at least part of the time because we have a fossilized track.

But why did bipedalism develop in the apes at all? Of all the apes, only humans developed bipedalism, and it actually still gives us a lot of problems: weak backs that are subject to injury, for instance, and even increased difficulty in childbirth, since the human pelvis had to change so much to adapt to walking upright. The cause was probably habitat change.

If you look at a map of Africa, you’ll see what looks like a string of lakes on the eastern side of the continent. Those lakes, and the volcanoes scattered around the area, including Mount Kilimanjaro, are caused by the East African Rift. Researchers are still working out what exactly is causing the rift, but we do know what’s happening in general. The tectonic plate Africa sits on, which is naturally known as the African Plate, is splitting in two.

This sounds alarming, especially if you happen to live there, but it’s a ridiculously slow process from our point of view. The rift widens barely seven millimeters a year. But that adds up when you’re talking millions of years, and the rift started at least ten million years ago and will continue for another ten million years until the plates separate completely and those lakes become part of the ocean.

Around the time the rift started forming, the East African plateau rose up, accompanied by a lot of volcanic activity. This caused a major change in the local habitats. What had once been thick forest and lush jungle became open woodland and savanna. Grasses grew tall, there wasn’t as much cover, and the animals that evolved and moved into the area were fast runners. It wasn’t a great area to be a knuckle-walker like other apes, but it was ideal for apes who could stand and walk upright.

The rift is where we’ve found so many important hominin fossils, including that of Lucy. Lucy was an Australopithecus who lived 3.2 million years ago. In Ethiopia, where the partial skeleton was found, she’s known as Dinknesh, which means “you are marvelous” in the local language.

That kind of makes me want to cry a little. Lucy wasn’t just some ape who could walk upright part of the time while carrying things. She was our great-great-great-a million times-great grandma.

[oops copyright infringement hahahahahahahahahahaha]

By around two and a half million years ago, Homo habilis had evolved. Homo habilis probably still looked a lot like an ape, but was also getting recognizably human. They walked upright all the time and made stone tools. Then, a little less than two million years ago, Homo erectus appears in the fossil record.

Homo erectus was definitely human-looking, with a human-like nose, ordinary human-sized height, and very little hair except on the head. And Homo erectus had dark skin, which is linked to the loss of body hair.

By a little less than one million years ago, Homo erectus was wearing clothes, cooking their food, and were adept in making and using stone tools. If you went back in time and met a Homo erectus, you’d think you were just meeting a really weird-looking person—and you would be right. Also, where did you get the time machine and can I get a ride in it?

By 200,000 years ago, modern humans, Homo sapiens, had fully evolved. If you could go back in time and meet those early humans, they would look, act, and think like the people you see around you today.

Of course, evolution isn’t as cut and dried as it sounds here. When one species evolves over long, slow generations into another, that doesn’t mean the population it evolved from vanishes. You may have heard the so-called argument against evolution: if humans evolved from monkeys, why are there still monkeys?

Well, first of all, apes and monkeys are different animals entirely. Both monkeys and apes, and all the other primates, evolved from a distant ancestor that wasn’t a monkey or an ape, but which had the characteristics that made it distinctly primate instead of feline or canine or hippopotamine…that’s not a word.

Second of all, species evolve because of environmental pressures, and those same pressures may not be present in all parts of the species’s range. Homo erectus survived well into the era of modern humans, and in fact we probably killed them off, either directly (because remember, we can be jerks) or indirectly by outcompeting them in the same habitats.

At some point, humans started moving out of Africa into other parts of the world, maybe about 55,000 years ago although we’re not really sure yet. Researchers are still working it all out, but some research suggests there might be more than one wave of migration, or that the migration started much earlier than 55,000 years ago.

The hominins I’ve mentioned so far weren’t the only ones around. Those were only our direct ancestors. There were others who split off from our ancestors and evolved separately, and if they hadn’t all died out (again, thanks to us, Homo sapiens jerkuses), we’d have populations of living cousins who are much more closely related to us than the other great apes. So let’s learn about some of them!

I’ve actually been putting off doing this episode because right now, we’re in the middle of a golden age of hominin discoveries. I kept thinking that if I just waited a few more weeks or months, new findings might very well be announced. In fact, right after I started research, sure enough, new information was published about a recently discovered Denisovan baby tooth.

There are two known groups of hominins who aren’t direct human ancestors to Homo sapiens, Neanderthals and Denisovans. They were around at the same time as modern humans for at least a while, but not usually in the same places.

Neanderthals spread throughout parts of northern Europe and Asia, and the Denisovans spread into Asia and down through the Malay Archipelago and into Australia. Again, I need to stress that these were not direct human ancestors. While they could and did interbreed with Homo sapiens, and many modern populations carry traces of Neanderthal and Denisovan DNA, there is no practical genetic difference in a human from one continent or background and a human from a different continent or background. We’re all human.

Around 1.8 million years ago, a population of Homo erectus migrated into Eurasia, where they gave rise to Neanderthals and Denisovans. When humans later migrated into the same areas, they encountered their close cousins and lived alongside them for possibly as long as 10,000 years before the human population increased to the point that…those other guys? They had to go.

The first Neanderthal fossils were discovered in 1829 in Belgium, but it’s the 1856 discovery of fossils in a cave in Neader Valley in Germany that gave us their name. “Thal” [pronounced like the word tall] means dale or valley in German, spelled with a TH, which is why so often the name is pronounced Neander-thal. It doesn’t really matter how you pronounce it.

Anyway, there’s still a lot of controversy regarding whether Neanderthals are a subspecies of Homo sapiens or a separate species in their own right. One incredibly “clever” and just precious suggestion in 1866 was that the group be named Homo stupidus. In fact, Neanderthals were probably as smart as humans and were definitely bigger and stronger than us (so don’t make jokes about them). They were well adapted to the cold with a barrel chest, relatively shorter limbs than humans, and an overall more robust build. They probably had better eyesight than we do too. Genetic evidence suggests that some populations may have had light skin and red or blond hair.

But it’s possible they weren’t as socially adept as humans. The average Neanderthal social group consisted of a close family unit—mother, father, and kids, or brothers and their mates, who were not related to one another, plus their kids—rather than extended relatives and related families, as is typical among humans. It’s likely that several family groups sometimes came together to share particular bonanzas in food. Neanderthals frequently killed mammoths, and a full-grown mammoth could feed a whole lot more than one family before the meat spoiled.

Grandparents probably weren’t usually part of most family groups not because no one liked their Grandma back then, but because Neanderthals had short, brutal lives. They speared mammoths at close range to kill them. That is metal as heck, but it’s also really hard on the body. It was rare for a Neanderthal to survive past 30, and by then he or she would look like an old, old person due to all the injuries sustained while hunting.

The authors of the marvelous book How to Think Like a Neandertal, which I’m drawing from quite a lot here, point out that Neanderthals and rodeo cowboys show similar patterns of injury over their lifetimes. And Neanderthals didn’t have hospitals and doctors they could visit.

While Neanderthals did make stone tools and use fire, analysis of their campsites shows sometimes interesting compared to human campsites. There’s no central fire pit. Almost every individual had their own fire where they did their own thing. In prehistoric human campsites, way back 25,000 years ago and even more, there’s generally one central fire that everyone gathers around. We still do this the world over. Can you even imagine going to summer camp and every kid spends the evening alone, tending their own little campfire and not singing camp songs, not spelling spooky stories, not eating s’mores together?

In addition, while there have been some controversial theories over some findings, as far as we can determine, Neanderthals didn’t make art. Some perforated seashells have been found at two Neanderthal sites in Spain that researchers think may have been worn as pendants, and we have evidence that Neanderthals, like other hominins for at least 300,000 years, used mineral pigments as body decoration. But they didn’t appear to use ceremonial items, didn’t create clothing beyond rough hide blankets or wraps, and they only had the barest minimum of funerary rites. Neanderthals may have been strong and smart, but they don’t appear to have been especially creative by our standards.

One old man Neanderthal, who was probably not more than 35 when he died, was so injured that he could probably not walk or do much of anything else by the final years of his life. He had lost most of his teeth and wouldn’t have been able to eat. But he lived for years, because someone helped him. Someone brought him food. Someone probably chewed it for him. And when he died, someone tucked him in a shallow hole and scattered dirt over his body. So however different Neanderthals were from us, they were also people.

By about 40,000 years ago, Neanderthals were extinct. That was probably too long ago to have left any traces in human collective memory, but that’s something I’ll bring up in part two of this episode next week.

We still don’t know much about the Denisovans because we only discovered the first specimen, a fragment of a finger bone, about ten years ago. The bone is from a young woman who lived about 41,000 years ago and was found in the Denisova Cave in Siberia, in the mountains not far from China and Mongolia. Since then, scientists have also found some teeth from two different adult males, and a baby tooth from a little girl who lived much earlier than the others.

According to DNA testing done on the finger bone, Woman X, as the finger’s owner is called, was neither a modern human nor a Neanderthal, although she was related to both and could interbreed with both. Denisovan DNA has been found in some populations of humans. Not only that, Woman X contained some Neanderthal DNA and DNA from an ancient human lineage that we don’t yet recognize. So there’s at least one other hominin we haven’t yet discovered. A toe bone has also been found that may be from a hybrid Denisovan-Neanderthal, but we don’t know for sure yet, since studies are still ongoing.

We don’t know what the Denisovans looked like, but just going from Woman X’s finger bone, which is much thicker than even a big human’s finger bones, we can guess they were pretty robust people. They may have looked a lot like Neanderthals. Some fossils thought to belong to Neanderthals may actually be Denisovan, so I bet a lot of museum and university collections are being examined closely right about now.

The Denisova Cave was used as a home by humans, Neanderthals, and Denisovans at different times going back some 125,000 years, and as recently as the 18th century, when a Russian hermit named Denis lived there. A bracelet discovered in the same layer of soil where Woman X’s finger bone was found has been dated to about the same time as the bone and is not a human artifact as far as archaeologists can tell.

It’s a green chlorite bracelet, carefully carved and beautifully polished. It was probably worn on the right wrist. It’s delicate, fragile, and probably belonged to someone important who wore it on important occasions. In other words, Denisovans wore and probably made jewelry. Unlike Neanderthals, they probably had important occasions.

A marble ring was found at the same time as the bracelet, but no information on it has been released yet. Hopefully, it won’t be long before we learn more about these new cousins of ours. They seem like interesting people.

That’s it for part one of our episode on humans. Next week we’ll take a look at some less closely related and more mysterious human relations, especially ones known as Hobbits for their small stature. Maybe by then you’ll have gotten that Toto song out of your head.

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 Podchaser, or just tell a friend. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 019: The Dodo and the Clam

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Thanks to Varmints! podcast for suggesting the dodo for this week’s topic.

And thanks to Two Clams Gaming podcast for suggesting clams as this week’s topic.

It’s two suggestions in one fun episode! Learn all about that most famous of extinct birds and all about a thing that tastes great deep-fried. (Well, okay, everything tastes great deep-fried. But you know what I mean.)

The dodo:

A giant clam and its algae pals:

Stop, thief! Put that clam down!

The disco clam looks as awesome as its name implies. It looks like a Muppet clam:

Calyptogena magnifica hanging out around a hydrothermal vent:

Show transcript:

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

We’re getting backed up on suggestions, so I’m going to combine two in one episode today even though they don’t really have anything to do with each other. The first suggestion is from the podcast Varmints, a super fun podcast about animals. They want to know about the dodo. After that, we’ll go on to learn about clams. Yes, clams! Totally not anything to do with dodos, but the hosts at Two Clams Gaming suggested it. That’s another fun podcast, this one about video games—which you may have guessed. I’ll have links to both podcasts in the show notes for you to check out.

The dodo isn’t just extinct, it’s famously extinct. Dead as a dodo. That makes it difficult to research the dodo, too—type “dodo” into the search bar at Science Daily, for instance, and you get a ton of hits that have nothing to do with the actual dodo bird, like the article that says “Researchers believe they now know why the supersonic trans-Atlantic Concorde aircraft went the way of the dodo.” I don’t care. I’m here for the birds. Lots of animals and birds have gone extinct over the years, unfortunately. Why is the dodo special?

The first known sighting of a dodo was in 1598 by Dutch sailors who stopped by the island of Mauritius in the Indian Ocean. The last known sighting of a dodo was in 1662, just 64 years after those Dutch sailors noticed a weird-looking bird walking around. The dodo went extinct so quickly, and was so little known, that for a couple of centuries afterwards many people assumed it was just a sailor’s story. A big stupid bird that couldn’t fly that would walk right up to a sailor and let itself be killed? No way was that real.

But there were remains of dodos, and in the 19th century scientists gathered up what they could find and studied them. More remains were found on Mauritius. Pretty soon researchers had a pretty good idea of what had happened. The dodo had no predators on Mauritius so was able to live in a birdie garden of Eden, eating fruit and nuts, wandering around admiring the scenery, making new dodos. It grew big and happy, lost the ability to fly, and nested on the ground since almost nothing was around that might eat its eggs. Then humans showed up, happy to eat not just the eggs but the meat of any dodos they could find, although reports were that while the meat tasted pretty good, it was really tough. What the sailors didn’t eat, the animals they brought with them did, like pigs and dogs. It was a stark and clear picture of human-caused extinction, shocking to the Victorian naturalists who studied it. The dodo became a cautionary tale and early rallying cry for conservation.

We all have a mental image of what the dodo looks like just because it’s appeared in so many cartoons and children’s stories, from Alice in Wonderland to that Madagascar movie. But what did the dodo actually look like?

Well, it looked just like the cartoon versions of itself. This really was a silly-looking bird. It was big, over three feet tall, with brown or gray feathers, a floofy tuft of gray feathers as a tail, big yellow feet like a chicken’s, and a weird head. The feathers stopped around the forehead if birds had actual foreheads, making it look sort of like it was wearing a hood. Its face was bare and the bill was large, bulbous at the end with a hook, and was black, yellow, and green. The dodo looks, in fact, a lot like what you might expect pigeons to evolve into if pigeons lived on an island with no predators, and that’s exactly what happened. The dodo is closely related to pigeons and doves. Its closest living relative is the Nicobar pigeon, a large, gorgeous bird with iridescent feathers. Like other pigeons, the dodo’s feathers probably had at least some iridescence too.

The dodo wasn’t clumsy and it wasn’t necessarily fat. A lot of the drawings and paintings we have of dodos were made from badly taxidermied birds or from overfed captive birds. At least eleven live dodos were brought to Europe and Asia, some bound for menageries, some intended as pets. The last known captive dodo was sent to Japan in 1647. In the wild, the dodo was a sleek bird that could run quite fast. It may have eaten crabs and other small animals as well as roots, nuts, seeds, and fruit. The dodo was also probably pretty smart. People only thought it was dumb because it didn’t run away from sailors—but it had never had to worry about anything more dangerous than an occasional egg-stealing crab before.

The dodo wasn’t the only creature on Mauritius to die out after ships started visiting the island, either. Other birds went extinct too, like the red rail, the broad-billed parrot, the Mauritius owl, and many others. So did animals like the Mauritian giant skink, two species of giant tortoise, and the small Mauritian flying fox. Even some plants, like the palm orchid, are long gone. Worse, there were undoubtedly dozens of species that went extinct without any human ever seeing them. We’ll never know the extent of the loss.

The stuffed dodos some museums display aren’t real. All we have of real dodos are bones and one dried head. Back in the 17th century, taxidermy was pretty primitive. Skins often weren’t treated with preservatives at all, and the preservatives that were in use didn’t last very long. There aren’t any taxidermied animals from before around 1750. Bugs ate them up.

The dodo is frequently mentioned when people bring up de-extinction. That’s the term used for cloning an extinct animal or genetically modifying a living animal to closely resemble an extinct ancestor. The dodo would be a good candidate for de-extinction since its habitat still exists. The problem is that we don’t have much genetic material to draw from. But DNA sequencing gets more sophisticated every year, so fingers crossed that a hundred years from now, there might be dodos on Mauritius again.

We know a decent amount about the dodo, but one of its close relatives, the spotted green pigeon, is an utter mystery. It’s extinct too, but we only have one specimen—there used to be two, but no one knows where the second one went. For a long time researchers weren’t even sure the spotted green pigeon was a distinct species or just a Nicobar pigeon with weird-colored feathers, but in 2014, DNA testing on two of the remaining specimen’s feathers showed it was indeed a separate species. Researchers think the spotted green pigeon, the dodo, and another extinct bird, the Rodrigues solitaire, all descended from an unknown pigeon ancestor that liked to island hop. Sometimes some of those pigeons would decide they liked a particular island and would stay, ultimately evolving into birds more suited to the habitat.

Because there were no scientific studies of Mauritius and its two closest islands until the 19th century, there’s been a lot of confusion about what birds lived where before they went extinct. For a long time researchers thought there was a variety of dodo on the island of Reunion with light-colored or white plumage. The white dodo was sometimes called the solitary dodo, causing confusion with the related flightless bird, Rodriguez solitaire. The island of Rodriguez is about 300 miles east of Mauritius. In 1987 fossils of a type of ibis were found on Reunion, and in 1995 they were connected with accounts of the Reunion solitaire, a flightless white bird with black markings that went extinct around the same time as the dodo. Researchers now believe reports of the white dodo from Reunion were actually describing the Reunion solitaire, now called the Reunion ibis. No dodo remains have ever been found anywhere except on Mauritius.

If all that sounds confusing, consider that when dodos were still alive, people referred to them as everything from ostriches to penguins. And no one has any idea where the name dodo actually came from.

As far as we know, the dodo only laid one egg at a time. It probably fed its baby with crop-milk like other pigeons and doves. That’s a substance that’s formed from the protein-rich lining of both parent bird’s crops, which detaches from the crop, is regurgitated by the parent and fed to the babies. It’s not anything like mammal milk but it’s pretty neat. The only other birds known to produce something similar are flamingos and some species of penguin, although in those birds the secretion comes from the lining of the esophagus. In pigeons and doves, the parents feed the babies exclusively on crop milk for the first week of life, then start mixing in regular food that’s been softened in the parent’s crop. I suppose I should explain that the crop is a sort of extra stomach where food is stored before being digested. It allows a bird to gorge itself if it comes across a lot of food. Not all birds have a crop.

One last interesting thing about the dodo. In 1973, botanists studying Mauritius couldn’t figure out why the tambalacoque, also called the dodo tree, was dying out. Supposedly only 13 trees remained, all around 300 years old, although that number seems to be mistakenly low. While the dodo trees produced seeds, very few of them germinated. Biologist Stanley Temple suggested that the tough-shelled seeds needed to pass through the digestive tract of the dodo to germinate properly. The dodo had a powerful gizzard that it filled with small stones it swallowed, which helped grind up tough plant materials. Temple hypothesized that by passing through the gizzard, the dodo tree seeds were abraded enough to germinate. He fed some of the seeds to turkeys, which have similar gizzards, and the recovered seeds promptly germinated. Botanists now use gem polishers—and sometimes turkeys—to abrade the seeds.

[bird sound]

Until I started my research for this episode, the only thing I knew about clams was that they’re really good fried. Oh, and that they have two shells that are super common and boring when you’re beachcombing. Specifically, they’re bivalve mollusks, but they’re not the only bivalve mollusks. Scallops, oysters, and mussels are too, and some close relations include slugs, snails, and squids.

Clams live in oceans and fresh water throughout the world. They start life as microscopic larvae that drift through the ocean eating plankton for a few weeks before attaching themselves to a piece of sand, gravel, shell, or whatever. At that point they burrow into the mud or sand until they develop their own shells. The adults live most of their lives partially buried in the sand in shallow water. Clams are filter feeders, sucking in water through a tube called a siphon and straining it with tiny hair-like structures called cilia.

The smallest clams are just .1 millimeter long. The biggest clam is the giant clam that lives in the Pacific and Indian oceans. These are the ones that used to be featured in short stories about divers in peril, their arm trapped by a giant clam and their air supply running out. What to do?? Or maybe I just read some weird stuff as a kid.

The giant clam can grow over four feet across and can live for more than a hundred years. It’s the only clam that can’t close its shell completely, especially as it gets bigger. Its mantle, the inside fleshy part of its body, protrudes past the edges of the shell like big stripey clam lips. But the giant clam spends most of the day with its shell open so that sunlight reaches the algae that live inside its mantle. The algae help feed the clam.

Giant clams are edible and have the reputation as being an aphrodisiac. As a result, they’re becoming more and more endangered, especially since the biggest shells are also worth money on the black market. Who knew there was a black market for clam shells? Seriously, people will spend money on anything. The next person contemplating dropping cash for an illegally harvested giant clam, do me and the clams a favor and buy me a nice set of cymbals for my drum kit instead, okay? Fortunately, giant clams can be raised in captivity and released into the wild.

And no, divers don’t get caught and drowned by giant clams. That’s a myth.

While most pearls are made by oysters, lots of mollusks can make them, including clams. The giant clam naturally produced the largest pearl ever found. It weighs 75 pounds. The Filipino fisherman who found it kept it under his bed for ten years as a good luck charm. It’s a foot in width and over two feet in length. It’s supposed to be worth over a million dollars, but don’t think about turning to a life of crime. A few months ago, in March of 2017, ten men were arrested for illegal possession of giant clam pearls and the giant clams themselves. Book em, Danno.

Different species of mollusk produce pearls of different color. The Ko-hog clam, which is frequently made into chowders, occasionally produces a purple or lavender pearl. They’re not always very pretty—they may not have much of a lustre compared to oyster pearls, or are lumpy in shape. But when a pretty one does turn up, they can be worth a lot. In 2009, a man eating seafood stew at his birthday meal discovered a pearl in his bowl the size of a big pea, which he later sold for $16,500. I could buy, like, so many cymbals for that kind of money.

There are some weird species of clams out there. The disco clam lives in underwater caves in the Indo-Pacific Ocean. They flash brightly to scare off predators. Until a few years ago researchers assumed the lights were a type of bioluminescence, but it turns out that the flashes are caused by double-layered tissues. One of the layers is light absorbent and the other is highly reflective. The clam rolls and unrolls the tissues to flash the reflected light. The disco clam also appears to secrete noxious mucus to repel predators.

While most clams live in the shallows, there are some species that are found much deeper. In parts of the deep sea with a lot of volcanic activity, hydrothermal vents attract all kinds of marine life, including specialized clams. Calyptogena magnifica and its close relatives, which are big white clams that live around thermal vents, has no digestive organs. Instead, hydrogen-oxidizing bacteria live in its gills. The clam absorbs nutrients produced by the bacteria. Hydrothermal vents don’t last forever—they go cold as magma under the sea floor moves, and new vents will open up elsewhere. Researchers have recently discovered that some animals that live near hydrothermal vents, including clams, can also survive on sunken whale carcasses by chemically leaching energy from the oily whale bones with the help of bacteria.

One of the most popular edible types of clam is the Pacific gooeyduck. It has a relatively small shell, generally no bigger than about 8 inches long, but its siphon can be more than three feet long, with occasional record-setting individuals caught with siphons over six feet long. It’s another long-lived clam—it can live for hundreds of years. The siphon is considered a delicacy the world over, but frankly, if it’s not cut into strips and deep-fried, I don’t want to bother with eating clams. Not even if I might find a pearl.

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Thanks for listening!