Episode 367: The Marozi

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Thanks to Pranav for suggesting this mystery big cat this week, the marozi!

Further reading:

From Black Lions to Living Sabre-Tooths: My Top Ten Mystery Cats

Spotted Lions

A young lioness who still has some of her cub spots:

Subadult lions who still have a lot of cub spots:

The skin of an animal supposedly killed in 1931 and said to be a marozi:

Two photos of a “leopon,” a lion-leopard hybrid bred in captivity in a Japanese zoo:

Show transcript:

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

This week we’re going to learn about a mystery animal suggested by Pranav. It’s the marozi, a big cat from the mountains of Kenya.

Kenya is in east Africa, and humans have lived in what is now Kenya since humans existed. Because of this, usually when we talk about Kenya or east Africa, we’re talking about hominins, but today we’re talking about big cats.

Kenya is home to a lot of animals you think of when someone mentions the animals of Africa, like elephants and giraffes, and it’s also home to three big cats: lions, leopards, and cheetahs. The lion is generally a tawny brown color although different individuals and populations can be various shades of brown or gray. A lion cub is born with dark spots, and as it grows the spots fade. Sometimes a young adult lion will still have some spots, especially on its legs and belly, but in general an adult lion has no spots at all. In comparison, both the leopard and the cheetah are famous for their spots.

The lion prefers to live in savannas and open woodlands. These days it’s only found in a few parts of India, along with various places in sub-Saharan Africa. This just means south of the Sahara desert. In the past, though, the lion had a much larger range. It lived throughout most of Africa, the Middle East, southern Asia, and even southern Europe. Overhunting drove it to extinction in many parts of its historic range, which is called extirpation. I’ve used the term before but it specifically means that an animal has been driven to extinction in one area where it once lived, but it isn’t extinct in other areas. Some subspecies of lion have gone extinct, and the lions who remain are vulnerable to habitat loss, poaching, and many other factors. Just because lions are common in zoos doesn’t mean lions in the wild are doing fine.

The same is true of the cheetah, which has an even smaller range than the lion these days but which was once common throughout Africa and the Middle East along with a lot of southern Asia and Europe. We talked about the cheetah in episode 145. It’s actually not closely related to the lion or the leopard, and in fact genetic testing reveals that it’s most closely related to the puma of North America.

The leopard, on the other hand, is a very close relation to the lion. Both belong to the same genus, Panthera, which also includes tigers, jaguars, and snow leopards, but the lion and leopard are the closest cousins. While it’s also vulnerable to habitat loss, poaching, and other factors, it’s more widespread than the lion and cheetah. It lives throughout much of sub-Saharan Africa, Asia–especially India–and even parts of eastern Russia, and in the past it was even more widespread. It prefers forests where its spots help it blend in with dappled sun and shade.

So, the lion, the leopard, and the cheetah all live in Kenya, but there’s another big cat that’s supposed to live there too. It’s called the marozi, also sometimes called the spotted lion.

Stories of lions that have spots like a leopard go back for centuries among the local people. The spotted lion is supposed to be small and the male either has no mane or only a small one. It’s supposed to live in the mountains and is solitary instead of living in family groups like ordinary lions. In fact, “marozi” supposedly means “solitary lion” in the local language. Instead of living in open grasslands, it lives in thick forest where a spotted coat and smaller body size would be useful, allowing it to maneuver through the trees more easily while not being seen.

It wasn’t until the colonial era in the late 19th and early 20th centuries that Europeans became aware of the marozi. The first known sighting of a spotted lion by a European occurred in 1903, when a British soldier reported seeing more than one in the mountains of Kenya. He said the lions were darker in color than an ordinary lion, with leopard-like rosette markings. In 1924, a game warden reported killing a spotted lioness and her cubs, with the lioness having just as many spots as the babies.

In 1931 a farmer shot two small spotted lions in the mountains. He said they were fully grown despite their small size, but they had even more spots than lion cubs do. One was a male and he had a sparse, short mane. The farmer kept the male’s skin, which eventually made its way to the Natural History Museum in London, possibly with the lion’s skull too, although it’s not clear if the skull actually belongs to the same animal. As far as I could find out, no one has tried to test the skin and skull genetically.

Other people, including hunters and game wardens, reported seeing spotted lions in high elevations where ordinary lions didn’t live, with stories continuing through at least the 1960s. Similar stories of a spotted lion have been collected from mountains in other parts of east and central Africa, including Ethiopia, Rwanda, Uganda, and Cameroon, where it has different local names. But so far we don’t have any photographs or a specimen.

There are a few hypotheses about what the marozi might be. One suggestion is that it’s actually a hybrid of a leopard and a lion. Because leopards and lions are so closely related, they can interbreed and produce offspring, although as far as we know this has only happened in captivity. In the wild, lions are actually aggressive towards leopards. A lion will steal a leopard’s food and will sometimes even kill leopards, and as a result leopards try to avoid lions. Since leopards prefer thick forest and lions prefer open forest or grasslands, they don’t cross paths all that often anyway.

In the late 1950s into the early 1960s, a zoo in Japan kept a male leopard and a female lion in the same enclosure to see if they would mate. They did, and eventually they had two litters together. The cubs were larger and heavier than leopards but not as big as lions, and while they generally looked like lions they had leopard spots. The males had small manes.

This sounds a lot like reports of the marozi, but again, in the wild lions and leopards mostly avoid each other. The only time a lion and a leopard would consider each other potential mates instead of potential trouble is when they’re put together artificially as in the Japanese zoo. Even if an occasional leopard and lion do sometimes breed in the wild, it wouldn’t happen often enough to cause all the sightings documented about the marozi. Besides, the marozi is only reported from the mountains, where lions don’t live.

Another hypothesis is that there’s a population of ordinary lions that have moved into the mountains to escape factors like habitat loss, poaching, and a decline in prey animals, and that people occasionally see a young adult lion that hasn’t completely lost its cub spots. This isn’t too likely either since stories of the marozi go back to long before these modern pressures on lion populations.

There might very well be an unknown, very rare species or subspecies of lion that has always lived in the mountains in parts of east and central Africa, and that it does actually have spots as an adult. If this is the case, hopefully it’s safe in its mountain habitat from the pressures faced by ordinary lions. Let’s hope also that it comes to the attention of scientists soon so it can be studied and protected.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 366: The Muntjac AKA Deer with Fangs

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Thanks to Chuck for suggesting this week’s topic, a weird little deer called the muntjac!

Further reading:

Dam Project Reveals Secret Sanctuary of Vanishing Deer

Wildlife camera trap surveys provide new insights into the occurrence of two threatened Annamite endemics in Viet Nam and Laos

Getting ahead (or two?) with Vietnam’s Viking Deer – the Long-Running Saga of a Slow-Running Mystery Beast

A giant muntjac [photo by Mark Kostich, taken from article linked above]:

A Reeve’s muntjac [photo by Don Southerland, taken from this site]:

Show transcript:

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

This week we have a suggestion from Chuck, who wanted to learn about a small hoofed animal that I don’t think we’ve ever covered before, the muntjac. It’s a deer, but it’s a very weird deer.

In fact, it’s not just one deer, it’s at least 12 different species that are native to parts of south and southeast Asia, although it used to have a much broader range. Muntjac fossils have been found throughout Europe in particular. It prefers thick forests with lots of water around. Most species live in tropical or subtropical areas, although it can tolerate colder temperatures. It eats leaves, grass, fruit, seeds, and other plant parts, and it will also sometimes eat bird eggs and small animals when it finds them. It will even sometimes eat carrion.

The typical muntjac is small, barely larger than a fox. The largest species, the giant muntjac, stands a little over two and a half feet tall at the shoulder, or 80 cm, while there are several species of muntjac that don’t grow taller than 15 inches high, or 40 cm. It’s brown or reddish-brown, sometimes with darker or lighter markings depending on species. The muntjac appears hump-backed in shape like a rabbit, since instead of having a mostly level back, its back slopes upward from the shoulders to the rump. Its tail is very short and males grow short antlers that either have no branches or only one branch. Males also have a single pair of sharp, curved fangs that grow down from the upper jaw, more properly called tusks.

The muntjac is usually a solitary animal, with each individual defending a small territory. Both males and females have a large gland near the eye that secretes an oily substance with a strong smell. It also has another pair of scent glands on the forehead. The muntjac rubs its face on the ground to mark the edges of its territory with scent. It can even flare its scent glands open to communicate with other muntjacs by smell more effectively.

Unlike many deer species, the muntjac doesn’t have a particular mating season. Females, called does, can come into season any time of the year, so males are always ready to fight with other males for a doe’s attention. The male loses and regrows his antlers yearly, but mainly he only uses them to push an opponent over. He does the real fighting with his fangs.

There are other types of hoofed animals with fangs. We talked about the musk deer and the chevrotain in episode 116, but even though the chevrotain in particular looks a lot like the muntjac, it’s not closely related to it at all. Neither is the musk deer. In fact, neither the musk deer nor the chevrotain are actually deer, and they’re not even closely related to each other.

The southern red muntjac is one of the smallest species of muntjac known and is fairly common throughout much of southeast Asia, although we don’t know much about it. One thing we do know is that it has the smallest number of chromosomes of any mammal ever studied. Males have 7 diploid chromosomes and females only have 6. In comparison, the common Reeve’s muntjac has 46 diploid chromosomes. Scientists have no idea why there’s so much difference in chromosome count between species, but it works for the muntjac.

Many species of muntjac are common and are doing just fine, but others are endangered due to habitat loss, hunting, and the other usual factors we talk about a lot. But the muntjac is small, solitary, and very shy, so there are also species that are probably still waiting to be discovered.

The giant muntjac, also called the large-antlered muntjac, was only discovered in 1994 from a skull found in Vietnam. Scientists were eager to learn more about the animal, especially whether it was still alive or had gone extinct. They talked to hunters and other local people in Vietnam and Laos, and set up camera traps, and went on expeditions searching for it. The hunters said it was still around but the scientists just couldn’t find any. It wasn’t until 1997 that a camera trap took a few pictures of one near a newly constructed dam, which gave everyone hope that this animal could be saved from possible extinction.

Scientists had been searching for the giant muntjac for so long, and had only finally gotten a photograph after 13 years of trying, that they figured it would be an even longer time before they learned more about it. But then, suddenly, only four months after the first pictures of the giant muntjac were captured, a team of conservationists working to relocate animals from the flood area of the new dam ended up capturing 38 of the deer.

When a new dam is constructed across a river or other waterway, it doesn’t flood right away. It takes a long time for the water to back up behind the dam and turn into a lake or large pond, sometimes several years depending on the size of the dam and the waterway. There’s time to relocate animals to higher ground so they’ll be safe, and that’s exactly what Ulrike Streicher and her team were doing in 2007. Not only that, they made sure to transport the animals to a protected area where they’d be safer from hunters. Before they released the giant muntjacs, they had the opportunity to study them and fit some of them with radio collars so the scientists could track where they went. It turned out that the muntjacs settled into their new home just fine, so although the giant muntjac is still classified as critically endangered, at least we know that one small population is doing well.

Another muntjac search involves a camera trap in Vietnam and Laos too, but it’s still an ongoing mystery. The story actually starts back in 1929 when a dead muntjac was sent to the Field Museum in Chicago. The scientists at the museum couldn’t identify it as any known species of muntjac, so they described it in 1932 as Muntiacus rooseveltorum, also called Roosevelt’s muntjac. Modern genetic testing of the specimen determined that it’s a subspecies of Fea’s muntjac that lives in a small area of southern Myanmar and Thailand. Fea’s muntjac itself is so rare and so little known that we don’t even know if it’s extinct or not. As for Roosevelt’s muntjac, no one had seen it since the 1929 specimen was killed and it was presumed extinct.

Then, starting in 2014, a team of scientists conducted surveys in parts of the Annamites, a mountain range along the Vietnam/Laos border. Over the next five or six years, camera traps recorded every animal that passed by them in various remote locations. In addition to lots of animals the scientists expected to see, they found three animals that were either extremely rare or thought extinct. One of these was the Annamite striped rabbit we talked about in episode 254, but the other two were muntjacs.

One of the muntjacs captured on camera was identified as Roosevelt’s muntjac while the other was identified as the Annamite muntjac, a species that was only identified in 1997. The problem is that we only have pictures of the animals, and only a single specimen of Roosevelt’s muntjac to compare the pictures to. Scientists disagree as to whether Roosevelt’s muntjac is for sure still alive and well in the Annamite mountains, or whether the pictures are of a totally different species of muntjac. At least the pictures were taken in a nature reserve, so we know the muntjacs should be safe.

Muntjacs are such strange, attractive animals that rich people used to keep them as pets to show off. Sometimes they would escape into the wild, or were even released on purpose, and that’s why Japan, England, Wales, Belgium, the Netherlands, and Ireland all have invasive populations of Reeve’s muntjac. Reeve’s muntjac is common in southeastern China and Taiwan and only grows a little over a foot high at the shoulder, or maybe half a meter. The male has stubby little antlers and long tusks, so that his tusks are almost as long as his antlers. Cute as the animals are, they’re also bad for the local ecosystems, since they reproduce quickly and eat food that native animals need.

Rumors have circulated for a few decades now of another possible mystery muntjac, usually referred to as the quang khem. Supposedly it’s a large muntjac with unbranched antlers that lives in remote areas of Vietnam. So far it hasn’t been discovered, if it exists at all, but there’s definitely a chance that it’s yet another muntjac that’s just waiting to be spotted by scientists or their camera traps.

The muntjac is sometimes called the barking deer because of its alarm call. This is what a muntjac sounds like:

[muntjac barking sound]

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 365: A New Temnospondyl

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Let’s take a look at some new findings about the temnospondyls this week!

Further reading:

Ancient giant amphibians swam like crocodiles 250 million years ago

Fossil of Giant Triassic Amphibian Unearthed in Brazil

Kwatisuchus rosai was an early amphibian [picture taken from article linked above]:

Koolasuchus was a weird big-headed boi:

Show transcript:

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

This week we’re going to revisit an animal we talked about way back in episode 172, the temnospondyl. That’s because a new species of temnospondyl has been named that lived about 250 million years ago, and some other new information has been published about temnospondyls in general.

In case you haven’t listened to episode 172 in a while, let’s brush up on some history. The temnospondyls arose about 330 million years ago during the Carboniferous period. Ocean levels were high, the continents were coming together slowly to form the supercontinent Pangaea, and much of the land was flooded with warm, shallow water that created enormous swampy areas full of plants. Naturally, a whole lot of animals evolved to live in the swamps, and the temnospondyls were especially successful.

Temnospondyls were semi-aquatic animals that probably looked a lot like really big, really weird salamanders. This was before modern amphibians evolved, and scientists still aren’t sure if the temnospondyls are the direct ancestors of modern amphibians or just cousins that died out with no living descendants. Temnospondyls do share many traits with modern amphibians, but they still had a lot in common with their fish ancestors.

Most temnospondyls had large heads that were broad and flattened in shape, often with a skull that was roughly triangular. Some had smooth skin but many had scales, including some species with scales that grew into armor-like plates. The earliest species had relatively small, weak legs and probably spent most of their time in the water, but it wasn’t long before species with stronger legs developed that probably lived mostly on land.

Many temnospondyls were small, but some grew really big. The biggest found so far is Prionosuchus, which is only known from fragmentary specimens discovered in Brazil in South America. It had an elongated snout something like a ghavial’s, which is a type of crocodilian that mostly eats fish, and a similar body shape. That’s why its name ends in the word “suchus,” which refers to a crocodile or an animal that resembles a crocodilian. Inside, though, prionosuchus probably had more in common with its fish ancestors than with modern crocodiles, and of course it wasn’t a reptile at all. It was an amphibian, possibly the largest one that’s ever lived. The biggest specimen found so far had a skull that measured just over 5 feet long, or 1.6 meters. That was just the skull! The whole animal, tail and all, might have measured as much as 30 feet long, or about 9 meters, although most paleontologists think it was probably more like 18 feet long, or 5-1/2 meters. That’s still incredibly big, as large as the average saltwater crocodile that lives today.

The resemblance of many temnospondyls to crocodilians is due to convergent evolution, since researchers think a lot of temnospondyls filled the same ecological niche as modern crocodiles. If you’re an ambush predator who spends a lot of time hiding in shallow water waiting for prey to get close enough, the best shape to have is a long body, short legs, a long tail that’s flattened side to side to help you swim, and a big mouth for grabbing, preferably with a lot of teeth. A study published in March of 2023 examined some trace fossils found in South Africa that scientists think were made about 255 million years ago by a temnospondyl. The fossils were found in what had once been a tidal flat or lagoon along the shore of the ancient Karoo Sea. You didn’t need to know it was called the Karoo Sea but I wanted to say it because it sounds like something from a fantasy novel. Truly, we live in a wonderful world. Anyway, there aren’t very many footprints but there are swirly marks made by a long tail and body impressions where the animal settled onto the floor to rest.

From those trace fossils, scientists can learn a lot about how the animal lived and moved. The swirly tail marks show that it used it tail to swim, not its legs. Since there are hardly any footprints, it probably kept its legs folded back against its body while it was swimming. When it stopped to rest, it may have been watching for potential prey approaching from above, since its eyes were situated on the top of its head to allow it to see upward easily. All these traits are also seen in crocodiles even though temnospondyls aren’t related to crocodilians at all.

Other big temnospondyls that filled the same ecological niche as crocodiles were species in the family Benthosuchidae. Some grew over 8 feet long, or 2.5 meters. That may not seem very big compared to a dinosaur or a whale, but this is your reminder that it was an early amphibian, and that amphibians are usually little guys, like frogs and newts.

The newly discovered fossil I mentioned at the beginning of this episode has been identified as a member of the family Benthosuchidae. It’s been named Kwatisuchus rosai and was discovered in Brazil in 2022. That’s a big deal, because while temnospondyl fossils have been found throughout the world, until Kwatisuchus, benthosuchids have only been found in eastern Europe. It was five feet long, or 1.5 meters, and it was probably an ambush predator that mostly ate fish.

Kwatisuchus lived only a few million years after the end-Permian extinction event, also called the Great Dying, which we talked about in episode 227. That extinction event wiped out entire orders of animals and plants. Temnospondyls in general survived the Great Dying and hung on for another 100 million years afterwards.

The last temnospondyl that lived, as far as the fossil record shows, was Koolasuchus. It lived in what is now Australia and went extinct about 120 million years ago. This is a lot more recent than most temnospondyls, so much so that when it was first discovered, scientists at first didn’t think it could be a temnospondyl. It was only described in 1997, although it was first discovered in 1978.

Not only was Koolasuchus the most recently living temnospondyl, it was also big and heavy and very weird-looking. It was about 10 feet long, or about 3 meters, and might have weighed as much as 1,100 lbs, or 500 kg. It lived in fast-moving streams and filled the same ecological niche as crocodiles, which eventually replaced it after it went extinct.

Like its relations, Koolasuchus had a roughly crocodile-shaped body with short legs and a fairly long tail, but its head was almost as big as its body. Most temnospondyls had big heads, and Koolasuchus’s was broad and rounded with a blunt nose. It also had what are called tabular horns that projected from the rear of the skull, which gave its head a triangular appearance. Its body was relatively slender compared to the chonky head, which made it look kind of like a really really big tadpole.

Remember, as an amphibian, Koolasuchus would have laid eggs that hatched into a larval form the same way frogs do today. We have a lot of larval temnospondyl fossils and even some fossilized eggs that paleontologists think were laid by a temnospondyl, which were attached to water plants the same way many species of frog do today. Larval temnospondyls did look a lot like tadpoles. In other words, Koolasuchus looked like a tadpole in shape but its larval form was also probably tadpole-like. Extra, extra tadpole-shaped.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 364: Animals Who Will Outlive Us All

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Thanks to Oz from Las Vegas for suggesting this week’s topic!

Further reading:

Bobi, the supposed ‘world’s oldest dog’ at 31, is little more than a shaggy dog story

Greenland sharks live for hundreds of years

Scientists Identify Genetic Drivers of Extreme Longevity in Pacific Ocean Rockfishes

Scientists Sequence Chromosome-Level Genome of Aldabra Giant Tortoise

Giant deep-sea worms may live to be 1,000 years old or more

A Greenland shark [photo by Eric Couture, found at this site]:

The rougheye rockfish is cheerfully colored and also will outlive us all:

An Aldabra tortoise all dressed up for a night on the town:

Escarpia laminata can easily outlive every human. It doesn’t even know what a human is.

Show transcript:

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

This week we have a great suggestion by Oz from Las Vegas. Oz wanted to learn about some animals that will outlive us all, and gave some suggestions of really long-lived animals that we’ll talk about. We had a similar episode several years ago about the longest lived animals,where for some reason we talked a lot about plants, episode 168, but this is a little different.

But first, a quick correction! Last week we talked about the dodo and some of its relations, including the Nicobar pigeon. I said that the Nicobar pigeon lived in the South Pacific, but Pranav caught my mistake. The Nicobar pigeon lives in the Indian Ocean on the Nicobar Islands, which I should have figured out because of the name.

Anyway, back in the olden days when I was on Twitter all the time, I came across a tweet that’s still my absolute favorite. Occasionally I catch myself thinking about it. It’s by someone named Everett Byram who posted it in January 2018. It goes:

“DATE: so tell me something about yourself

“ME: I am older than every dog”

Not only is it funny, it also makes you thoughtful. People live a whole lot longer than dogs. The oldest living dog is a chihuahua named Spike, who is 23 years old right now. A dog who was supposed to be even older, 31 years old, died in October of 2023, but there’s some doubt about that particular dog’s actual age. Pictures of the dog taken in 1999 don’t actually look like the same dog who died in 2023.

The oldest cat who ever lived, or at least whose age is known for sure, died in 2005 at the age of 38 years. The oldest cat known who’s still alive is Flossie, who was born on December 29th, 1995. If your birthday is before that, you’re older than every cat and every dog.

The oldest human whose age we know for sure was Jeanne Calment, who died in 1997 at the age of 122 years. We talked about her in episode 168. The oldest human alive today, as far as we know, is Maria Branyas, who lives in Spain and will turn 117 years old on her next birthday in March 2024.

It’s not uncommon for ordinary people to live well into their 90s and even to age 100, although after you reach the century mark you’re very lucky and people will start asking you what your secret for a long life is. You might as well go ahead and make something up now to tell people, because it seems to mainly be genetics and luck that allow some people to live far beyond the lives of any dog or cat or most other humans. Staying physically active as you age also appears to be an important factor, so keep moving around.

But there are some animals who routinely outlive humans, animals who could post online and say “I am older than every human” and the others of its species would laugh and say, “Oh my gosh, it’s true! I’m older than every human too!” But they don’t have access to the internet because they are, for instance, a Greenland shark.

We talked about the Greenland shark in episode 163. It lives in the North Atlantic and Arctic Oceans where the water is barely warmer than the freezing point. It can grow up to 23 feet long, or 7 meters, with females being larger than males. Despite getting to such enormous sizes, it only grows one or two centimeters a year, and that was a clue for scientists to look into how old these sharks can get.

In 2016, a team of scientists published a study about how they determined the age of Greenland sharks that had been accidentally caught by fishing nets or that had otherwise been discovered already dead. The lenses inside vertebrate eyeballs don’t change throughout an animal’s life. They’re referred to as metabolically inactive tissue, which means they don’t grow or change as the animal grows. That means that if you can determine how old the lens is, you know when the animal was born, or hatched in the case of sharks.

In the past, scientists have been able to determine the age of dead whales using their eye lenses, but the Greenland shark was different. It turns out that the shark can live a whole lot longer than any whale studied, so the scientists had to use a type of carbon-14 dating ordinarily used by archaeologists.

The Greenland shark may be the oldest-living vertebrate known. Its life expectancy is at least 272 years, and probably closer to 500 years. Individual sharks can most likely live much longer than that. It’s not even mature enough to have babies until it’s about 16 feet long, or 5 meters, and scientists estimate it takes some 150 years to reach that length. Females may stay pregnant for at least 8 years, and maybe as long as 18 years. Babies hatch inside their mother and remain within her, growing slowly, until they’re ready to be born.

The Greenland shark is so big, so long-lived, and lives in such a remote part of the ocean that taking so long to reproduce isn’t a problem. Its body tissues contain chemical compounds that help keep it buoyant so it doesn’t have to use very much energy to swim, and which have a side effect of being toxic to most other animals. Nothing much wants to eat the Greenland shark. But it is caught by accident by commercial fishing boats, with an estimated 3,500 sharks killed that way every year. Scientists hope that by learning more about the Greenland shark, they can bring more attention to its plight and make sure it’s protected. There’s still a lot we don’t know about it.

At least one species of whale does live much longer than humans. In 2007, researchers studying a dead bowhead whale found a piece of harpoon embedded in its skin. It turned out to be a type of harpoon that was manufactured between 1879 and 1885. After that, scientists started testing other bowhead whales that were found dead. The oldest specimen studied was determined to be 211 years old when it died, and it’s estimated that the bowhead can probably live well past 250 years if no one harpoons it and it stays healthy. It may be the longest-lived mammal. It has a low metabolic rate compared to other whales, which may contribute to its longevity.

Most small fish don’t live very long even if nothing eats them. Rockfish, for instance, only live for about 10 years even if they’re really lucky. Well, most rockfish. There is one species, the rougheye rockfish, that lives much, much longer. Its lifespan is at least 200 years old.

The rougheye rockfish has a lot of other common names. Its scientific name is Sebastes aleutianus. It can grow over 3 feet long, or 97 cm, and is red or orangey-red. It lives in cold waters of the Pacific, where it usually stays near the sea floor. It eats other fish along with crustaceans.

Naturally, scientists are curious as to why the rougheye rockfish lives so long but its close relations don’t. In 2021 a team of scientists published results of a genetic study of the rougheye rockfish and 87 other species. They discovered a number of genes associated with longevity, along with genes controlling inflammation that may help the fish stay healthy for longer.

The rougheye rockfish only evolved as a separate species of rockfish about ten million years ago. Because the longest-living females lay the most eggs, the genes for longevity are more likely to be passed on to the next generation, which means that as time goes on, lifespans of the fish overall get longer and longer. The rougheye also isn’t the only species of rockfish that lives a long time, it’s just the one that lives longest. At least one other species can live over 150 years and quite a few live past 100 years.

Another animal that can easily outlive humans is the giant tortoise, which we talked about in episode 95. Giant tortoises are famous for their longevity, routinely living beyond age 100 and sometimes more than 200 years old. The oldest known tortoise is an Aldabra giant tortoise that may have been 255 years old when it died in 2006. The Aldabra giant tortoise is from the Aldabra Atoll in the Seychelles, a collection of 115 islands off the coast of East Africa.

Scientists studied the Aldabran tortoise’s genetic profile in 2018 and learned that in addition to genes controlling longevity, it also has genes that control DNA repair and other processes that keep it healthy for a long time.

Oz also suggested the infinite jellyfish, also called the immortal jellyfish. An adult immortal jelly that’s starving or injured can transform itself back into a polyp, its juvenile stage. We talked about it in episode 343 in some detail, which was recent enough that I won’t cover it again in this episode. Scientists are currently studying the jelly to learn more about how it accomplishes this transformation and how long it can really live.

So far all the animals we’ve talked about, except the immortal jellyfish, are vertebrates. It’s when we get to the invertebrates that we find animals with the longest lifespans. The ocean quahog, a type of clam that lives in the North Atlantic Ocean, grows very slowly compared to other clams, and populations that live in cold water can live a long time. Sort of like tree rings, the age of a clam can be determined by counting the growth rings on its shell, and a particular clam dredged up from the coast of Iceland in 2006 was discovered to be 507 years old. Its age was double-checked by carbon-14 dating of the shell, which verified that it was indeed just over 500 years old when it was caught and died. Researchers aren’t sure how long the quahog can live, but it’s a safe bet that there are some alive today that are older than 507 years, possibly a lot older.

The real long-lived animals are very simple ones, especially sponges and corals. Some species of both can live for thousands of years. Various kinds of mollusks and at least one urchin can live for hundreds of years.

It’s probable that there are lots of other animals that routinely outlive humans, we just don’t know that they do. Scientists don’t always have a way to check an animal’s age, or they don’t think to do so while studying an organism. There are also plenty of animals that we just don’t know exist, especially ones that live in the ocean. For example, a species of tube worm named Escarpia laminata wasn’t even discovered until 1985, and it wasn’t until 2017 that scientists realized it lived for hundreds or even thousands of years.

The tube worm doesn’t have a common name, since it lives in the deepest parts of the Gulf of Mexico around what are called cold seeps, so no one ever needed to refer to it until it was discovered by scientists. A cold seep isn’t actually cold, it just isn’t as hot as a hydrothermal vent. In a cold seep, oil and methane are released into the ocean from fissures in the earth’s crust. Life forms live around these areas that live nowhere else in the world.

Many tube worms can grow quite long and can live over 250 years, with the giant tube worm growing almost 10 feet long, or 3 meters. Escarpia laminata is smaller, typically only growing about half that length. In a study published in 2017, a team of scientists estimated that it routinely lives for 250 to 300 years and potentially much, much longer. A tube worm doesn’t actually eat; instead, it forms a symbiotic relationship with bacteria that live in its body. The bacteria have a safe place to live and the tube worm receives energy from the bacteria as they oxidize sulfur released by the cold seeps. The tube worm, in other words, lives a stress-free life with a constant source of energy, and nothing much wants to eat it. The limit to its life may be the limit of the cold seeps where it lives. Cold seeps don’t last forever, although many of them remain active for thousands of years.

Humans are probably the longest-living terrestrial mammal. This may not seem too impressive compared to the animals we’ve talked about in this episode, but our lives are a whole lot more interesting than a tube worm’s.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 363: The Dodo and Friends

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Thanks to Wilmer and Carson for suggesting we revisit the dodo!

Further reading:

Dodos and spotted green pigeons are descendants of an island-hopping bird

On the possible vernacular name and origin of the extinct Spotted Green Pigeon Caloenus maculata

Giant, fruit-gulping pigeon eaten into extinction on Pacific islands

A taxidermied dodo:

The Nicobar pigeon, happily still alive [photo by Devin Morris – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=110541928]:

The 1823 illustration of the spotted green pigeon:

Show transcript:

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

This week we’re going to revisit a bird that everyone’s heard of but no one has seen alive, because it’s famously extinct. We talked about the dodo way back in episode 19, so it’s definitely time we talked about it again. Thanks to Wilmer and Carson for suggesting it! We’re also going to learn about some of the close relations of the dodo.

The first report of a dodo was in 1598 by Dutch sailors who stopped by the island of Mauritius in the Indian Ocean. Mauritius is east of Madagascar, which is off the eastern coast of Africa. The last known sighting of a dodo was in 1662, just 64 years later. 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. But there were remains of dodos, and in the 19th century scientists gathered up everything they could find to study the birds. More remains were found on Mauritius.

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. It was also probably pretty smart. People only thought it was dumb because it didn’t run away from sailors—but it had no predators on Mauritius so never had to worry about anything more dangerous than an occasional egg-stealing crab before.

When humans arrived on Mauritius, they killed and ate dodos and their eggs. What the sailors didn’t eat, the animals they brought with them did, like pigs and rats. It was a stark and clear picture of human-caused extinction, shocking to the Victorian naturalists who studied it.

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.

The dodo grew over three feet tall, or almost a meter, with brown or gray feathers, a floofy tuft of gray feathers as a tail, big yellow feet, and a weird head. The feathers stopped around the forehead, 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’s closest living relation is the Nicobar pigeon, which can grow 16 inches long, or over 40 cm. Like other pigeons, the dodo’s feathers probably had at least some iridescence, but the Nicobar pigeon is extra colorful. Its head is gray with long feathers around its shoulders like a fancy collar, and the rest of its body is metallic blue, green, and bronze with a short white tail. Zoos love to have these pigeons on display because they’re so pretty. It’s a protected animal, but unfortunately it’s still captured for sale on the pet black market or just hunted for food. It only lays one egg a year so it doesn’t reproduce very quickly, and all this combined with habitat loss make it an increasingly threatened bird. Scientists are trying to learn more about it so it can be better protected.

The Nicobar pigeon lives on a number of islands in the South Pacific and it can fly. Sometimes an errant individual is discovered in Australia, often after storms. Imagine going into your back yard one day and seeing a 40-centimeter-long bird whose feathers shine like jewels! The Nicobar pigeon lives in small flocks and eats seeds, fruit, and other plant material.

An even closer relative to the dodo is also the most mysterious. We don’t even know for sure if it’s extinct, although that’s very likely. It’s the spotted green pigeon and we only have one specimen–and we don’t even know where it was collected, just that it was an island somewhere in the South Pacific. There used to be two specimens, but no one knows what happened to the second one.

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.

The specimen we have of the spotted green pigeon is 13 inches long, or 32 cm. Its feathers are dark brown with green iridescence and it has long neck feathers like the Nicobar pigeon. It also has little yellowish spots on its wings and a yellow tip to its bill. Researchers think it was probably a fruit-eating bird that lived in treetops.

The only reason we know there were once two specimens of this mystery bird is from a book about birds published in 1783, where the author mentions having seen two specimens. There was also an 1823 book about birds with an illustration of the spotted green pigeon that differs from the known specimen in some details. Researchers think the illustration might have been painted from the now-missing specimen.

There’s more to this mystery, though, because in 2020 an ornithologist studied a 1928 book about Tahiti that mentioned a bird that sounds a lot like the spotted green pigeon. It was even called a pigeon in the book. Since the author of that book had drawn on studies made by her grandfather almost a hundred years before, and since her grandfather had interviewed Tahitians about their history and traditions and they told him about the pigeon, the ornithologist suggested the spotted green pigeon might actually be from Tahiti. Now that scientists have a clue about where to start looking for remains of the bird, we might learn more about it soon.

Also in 2020, a study was published about another pigeon from the Pacific Islands. Fossils of it were found on the island of Tonga, and the scientists determined that the bird probably went extinct soon after humans first arrived on the island 2,850 years ago. The pigeon has been named Tongoenas burleyi. It grew about 20 inches long, or 50 cm, not counting its tail. It could fly and probably spent a lot of its time in trees, eating fruit. There are lots of different trees on the island that produce really big fruit, some of it as big as a tennis ball. Scientists think the pigeon was adapted to swallow these huge fruits whole, digest them, and poop out the seeds. The trees still exist but they’re in decline and scientists think it may be because no birds remain on the island that can spread their seeds effectively.

We don’t have any feathers from the newly described pigeon, but it was probably colorful. We do have a lot of bones, because many charred bones have been discovered in cooking pits excavated by archaeologists.

We don’t know yet how or if Tongoenas is related to the dodo. The Pacific islands are home to at least 90 living species of pigeon, and many of them we don’t know much about. There are undoubtedly many more waiting to be discovered by scientists, whether living or extinct.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 362: The Sawfish and the Sawshark

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Thanks to Murilo for suggesting this week’s episode about the sawfish and the sawshark!

Further Reading:

Sawfish or sawshark?

Two New Species of Sixgill Sawsharks Discovered

Do not step:

The underside of a largetooth sawfish [photo by J. Patrick Fischer – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17421638]:

The sawshark has big eyes [photo by OpenCago.info – Wikimedia Commons [1], CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=25240095]:

A comparison of rostrums. The sawskate is in the middle, the one with barbels is the sawshark, and the really toothy one is the sawfish [picture by Daeng Dino – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=137983599]:

Show transcript:

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

This week we’re going to learn about an amazing fish suggested by Murilo. It’s the sawfish, and while we’re at it, we’re also going to learn about a different fish called the sawshark.

There are five species of sawfish alive today in two genera, and they’re all big. The smallest species can still grow over 10 feet long, or 3 meters, while the biggest species can grow over 20 feet long, or 6 meters. The largest sawfish ever reliably measured was 24 feet long, or 7.3 meters. Since all species of sawfish are endangered due to overfishing, pollution, and habitat loss, really big individuals are much rarer these days.

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

Let’s talk specifically about the largetooth sawfish for a moment, since we know the most about it. Like other sawfish, the female gives birth to live young, up to 13 babies at a time, and the babies can be up to three feet long at birth, or 90 cm. When a baby is born, its saw, which we’ll talk about in a minute, is covered with a jelly-like sheath that keeps it from hurting its mother. The sheath dissolves soon after birth.

The mother usually gives birth around the mouth of a river, and instead of swimming into the ocean, the babies swim upstream into the river. They live there for the next several years, and some individuals and even some populations may live their whole lives in the river. It’s sometimes called the river sawfish or the freshwater sawfish for this reason.

One interesting thing about the largetooth sawfish is how agile it is. All sawfish are good swimmers, but the largetooth sawfish is especially good. It can swim backwards, it can jump more than twice its own length out of the water, and it can climb over rocks and other obstacles using its fins, even if the obstacle isn’t completely submerged. It’s possible that other species of sawfish can do the same, but scientists just haven’t observed this behavior yet. We actually don’t know that much about most species of sawfish because of how rare they’ve become.

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

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

So, you may be asking, if the sawfish has plenty of teeth in its mouth, how and why does it also have those extra teeth on both sides of its saw? It’s because the rostral teeth evolved from dermal denticles. We’ve talked about dermal denticles a few times before, but a few months ago we had a Patreon bonus episode that went into more detail. In that episode, I talked about an article about a type of catfish, so let me just quote the whole section of that episode. It’s not long and I think it’s really interesting. Heck, I’ll just drop the audio in directly from that Patreon episode:

Our next article is from October 2017 and is intriguingly titled “When teeth grow on the body.” It sounds horrific, but it’s actually a study of certain catfish that grow bony plates with tiny teeth on their bodies as defense.

Catfish don’t have scales, but some species of denticulate catfish that live in South America grow bony plates that act like armor. Many of these plates are covered in thin little teeth–actual teeth, including enamel and dentin, with pulp inside. They’re called extra-oral teeth, dermal denticles, or odontodes, and the study determined that they appeared about 120 million years ago in ancient catfish that hadn’t yet evolved the bony plates. The teeth regrow when they’re lost, and in some species, males grow larger teeth than females and use them to fight other males. Imagine biting someone without needing to open your mouth.

Anyway, dermal denticles aren’t all that rare in fish. Sharks and rays are both covered with them. They’re also called placoid scales but they’re literally teeth, they’re just not used for eating. In the case of the sawfish, the rostral teeth grow much larger than an ordinary dermal denticle, and stick out sideways like the teeth of a saw. Different species have differently shaped rostral teeth. The teeth grow throughout the sawfish’s life, but unlike the teeth in the mouth, if the sawfish loses a rostral tooth, it doesn’t grow back. If it chips the top off a rostral tooth, though, that part will grow back.

The sawfish uses its rostrum to find the fish, crustaceans, and mollusks it eats. Both the rostrum and the head are packed with electroreceptors that allow the sawfish to sense tiny electrical charges that animals emit as they move. This might mean a school of fish swimming through muddy water, or it might mean a crustacean hiding in the sand. The sawfish sometimes uses its rostrum to dig prey out of the sand, but it also uses it to slash at fish or other animals. Then the sawfish can either grab the injured or dead animal with its mouth or pin it to the sea floor with its rostrum to maneuver it into its mouth. Its mouth is relatively small and it prefers to swallow its food whole, head-first, so it can only eat fish that are smaller than its mouth.

This means the sawfish leaves humans alone, because we’re way too big to fit into its mouth. It doesn’t want anything to do with us. Unfortunately, people keep bothering the sawfish, either by catching it illegally, leaving fishing nets and other trash in the ocean that sawfish and lots of other animals get tangled in, or by destroying its habitat with destructive dredging or trawling. The largetooth sawfish used to live around southern North America, but it relied on mangrove swamps to act as a nursery for baby sawfish. So many of the mangrove swamps have been destroyed so that people can build fancy hotels and shopping centers that the largetooth sawfish hasn’t been seen around North America in over 50 years, although the smalltooth sawfish is still hanging on.

Sawfish do well in captivity but require gigantic tanks, and even when given the best of care, they almost never breed in captivity. They live a long time, though, sometimes for decades.

Luckily for the sawfish, the female can reproduce without a male if she can’t find a mate. Instead of her eggs being fertilized by the male’s sperm, sometimes a female’s eggs will just develop into her genetic clones. Conservationists are working to make sure the sawfish and its habitat are protected so the babies can grow up safe and healthy.

We can’t talk about the sawfish without mentioning the sawshark. It’s a shark, not a ray, but it looks a whole lot like a sawfish–so much so that in places where both animals live, such as around Australia, people have a hard time telling them apart.

The sawshark mostly lives in much deeper water than the sawfish and is much smaller on average, about five feet long, or 1.5 meters. It has a pair of barbels about halfway down its saw that help it find food when there’s not much light to see by. Another major difference is that its gill slits are on the sides of its neck instead of under its body. It eats fish, squid, and crustaceans.

The sawshark’s rostrum also contains electroreceptors, although we don’t know for sure that it uses its saw the same way as the sawfish does. We actually don’t know very much about the sawshark, not even how many species are alive today. A new species was described in 2013 and two new species were described in 2020. There are probably more that are completely unknown to science, and maybe completely unknown to people in general.

Finally, there’s another fish that looks like a sawfish or sawshark, the sawskate, but its entire suborder, Sclerorhynchoidei, is completely extinct. It disappears from the fossil record 66 million years ago. I feel like I need a sound effect to play every time I mention that an animal went extinct 66 million years ago, to remind listeners that that’s the date of the extinction event that killed off the non-avian dinosaurs and many other animals. Maybe something like this. What do you think?

[comet sound]

Anyway, scientists are pretty sure the sawskate wasn’t very closely related to sawfish or sawsharks, but was more closely related to modern skates. Skates look a lot like rays but belong to a different family. Modern skates don’t have much of a rostrum at all, but the sawskate had a long tapering rostrum and some species had rostral teeth. Most species of sawskate were fairly small, but at least one grew an estimated 6 feet long, or about 2 meters.

If you’ve been thinking that a rostrum with teeth on both sides sounds like the kind of sword that old-timey warriors would use, you’re actually right. Traditionally, people in parts of the world where sawfish are common would sometimes use a big dried rostrum as a weapon.

These days, of course, sawfish are protected species. That means you can’t have a sawfish rostrum sword, sorry. Let the sawfish keep its sword.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 361: The New Hominin

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Welcome to 2024! Let’s learn about some exciting new discoveries in our own family tree!

Further reading:

476,000-Year-Old Wooden Structure Unearthed in Zambia

Mysterious 300,000-year-old skull could be new species of human, researchers say

Show transcript:

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

It’s time to start the new year off with an episode that has me really excited. I was initially going to include this in the updates episode that usually comes out around summertime, but I just can’t wait. In 2023, scientists discovered what they think might be a new lineage of extinct human ancestors!

We’ll come back to that in a moment, but first I want to highlight another amazing human-relateded discovery from 2023.

And just to let you know, I am going to be using the words “humans” and “people” and “hominins” more or less interchangeably. I try to make it clear when I’m talking about Homo sapiens versus other species of ancient hominin, but these are all our ancestors–in many cases our direct ancestors–so they’re all people as far as I’m concerned.

As you may know, especially if you’ve listened to previous episodes where we’ve discussed ancient human ancestors, the ancestors of all humans evolved in Africa. Specifically, we arose in the southern part of Africa, in areas that had once been dense forest but gradually changed to open woodland and savanna. Because there weren’t very many trees, our far-distant hominin ancestors, the australopiths, no longer needed to be able to climb trees as well as their ape cousins. Instead, they evolved an upright stance and long legs to see over tall grasses, and the stamina to run after the animals they hunted until the animal was exhausted and couldn’t run anymore. Once our ancestors were walking on two legs all the time, their hands were free to carry babies and food and anything else they wanted.

Being fully bipedal meant that women had a harder time giving birth, since the pelvis had to change position to allow them to walk and run, so babies started being born when they were smaller. This meant the babies needed a whole lot more care for a lot longer, which meant that family groups became even more important and complicated. One thing we’ve learned about sociability in animals is that it leads to increased intelligence, and that’s definitely what happened with our long-distant ancestors. As their brains got bigger, they became more creative. They made lots of different types of tools, especially weapons and items that helped them process food, but eventually they also made artwork, baskets, clothing, jewelry, and everything else they needed.

All this took a long time, naturally. We know Australopithecus used stone tools over three million years ago, but we don’t have evidence of human ancestors using fire until a little over 1.5 million years ago. Homo sapiens was once thought to have only evolved around 100,000 years ago, maybe less, but as scientists find more remains and are able to use more sophisticated techniques to study those remains, the date keeps getting pushed back. Currently we’re pretty certain that actual humans, if not the fully modern humans alive today, arose about 300,000 years ago and maybe even earlier. Homo sapiens evolved from Homo erectus, which arose about two million years ago and went extinct about 100,000 years ago. They were probably the first hominin to use fire, which allowed humans to start migrating longer distances into colder climates. They might also have communicated with language. Basically, Homo erectus was a lot like us but not quite us yet.

The modern-day country of Zambia is in the middle of south-central Africa, and naturally it’s been home to humans and our ancestors for as long as humans have existed. One especially important part of Zambia is also one of its most beautiful places, Kalambo Falls, which is really close to the equally important and beautiful country of Tanzania. Scientists have known that humans of one kind or another have lived around Kalambo Falls for at least 447,000 years, long before Homo sapiens actually evolved.

When a team of archaeologists excavated a sandbar near the falls in 2019, they were surprised to find wooden artifacts. Wood doesn’t usually preserve for very long and the site they were excavating was quite old. In addition to wooden tools, they found two logs that had been shaped and notched to allow them to fit together securely. The researchers thought the logs had once been part of a structure like a walkway that would keep people’s feet out of the mud and water, or possibly the floor of a wooden structure used to store food. It might even have been the floor of a little house.

Wood can be dated with simple tests to find out its age, but the test is only useful for trees that died within the last 50,000 years. Anything older than that is just, you know, older than 50,000 years. The tools and logs tested as older, which the scientists expected. Fortunately there are other ways to date older wood, but the results of those tests were surprising even to the scientists. The tools were at least 324,000 years old, possibly as much as 390,000 years old, but the logs were even older, about 476,000 years old.

Remember, Homo sapiens didn’t even evolve until about 300,000 years ago. That means humans didn’t make those tools or build anything with those shaped logs. Some other hominin did, although we’re not sure who. Even more exciting, close examination of the logs suggests that they may have been subjected to fire at some point. That might mean a natural fire or it might mean that the people who were building with the logs were also using fire as much as two million years before we thought people were using fire.

Obviously scientists are going to look carefully for more clues about who might have shaped these logs and when. Hopefully we’ll learn more soon.

Around the same time that scientists uncovered the wooden items in southern Africa, another discovery was made in 2019, this one in East China. A team found a jaw, skull, and leg bones of a hominin that didn’t match up to any known human ancestor. The bones were dated to 300,000 years ago, at the dawn of Homo sapiens. Other hominins had migrated to eastern Asia long before this, however, including populations of Homo erectus.

The newly discovered bones don’t belong to Homo erectus, though. They don’t belong to Homo sapiens either, or any other known hominin. They represent a completely new hominin, and at the moment scientists don’t know where exactly they fit in our own family tree.

The bones show traits found in modern humans, like a flat face, but lack other uniquely human traits, most notably a chin. Homo sapiens have chins, unlike every other hominin, and no one’s sure why. It might have something to do with speech or maybe early humans with chins were just considered more attractive, and now everyone has a chin.

The mystery hominin is still being studied, but preliminary findings indicate that we might have discovered the ancestor of a very close relation. The bones show some traits also found in Neandertals, our very closest evolutionary cousins, even though they’re extinct. There’s a possibility that this new hominin gave rise to another line of very close human relations, one we don’t have any fossils of yet.

I know there are a lot of excited scientists wanting to learn more about the hominin bones. Hopefully more bones will turn up soon so we can get a better idea of who this distant relative is. It’s a little too early to throw them a welcome home party, but maybe we can start planning it now.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 360: The Emu War

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Apologies to patrons for redoing an old Patreon episode, but I have a cold and it’s the holidays.

The noble emu:

A baby emu (picture from this site, which has lots of good info about emus and lots more great pictures):

Show transcript:

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

I had a different episode planned to finish off the year, but I had lots of stuff to do for the holidays so I put it off, and then I came down with a cold. It’s just a cold, at least, and it’s not too serious, but I decided to repurpose a Patreon episode from early 2020 instead of making a new episode, because I don’t feel good. Apologies to my patrons for getting a rerun, but I did give the episode a brush-up and re-recorded it.

Our topic this week is a bird from Australia, the emu, but mostly we’re going to learn about the emu war that happened in 1932.

The emu is a large, flightless bird almost as big as an ostrich, over 6 feet tall, or 2 meters. Like the ostrich, it can run really fast, over 30 miles per hour, or 50 km/hour. It’s only distantly related to the ostrich, though, and in fact it’s much more closely related to the tiny kiwi of New Zealand.

The emu has long legs and a long neck, soft feathers that are gray and brown, and three toes on each foot. It also has small vestigial wings that are only about eight inches long, or 20 cm. The body feathers make the emu look shaggy, but the head and the upper portion of the neck are less heavily feathered so that it sort of looks like it’s wearing a fancy coat with a high collar. It also looks like it has a poofy wedge of a downward-pointing tail, but it actually doesn’t have much of a tail at all. What looks like a tail is mostly part of the body. The emu’s skeleton is built for running, which includes a modified pelvis and leg bones for the attachment of strong leg muscles.

In winter, the female puffs out her feathers and struts around to attract a mate while making drumlike calls. Females sometimes fight each other by kicking, especially if a female approaches a male who already has a mate. The male builds a nest on the ground by placing dry grass, sticks, bark, and other plant materials on a flat, open area where he can see any predators that might approach.

The female lays up to 15 green eggs that are around five inches long, or 13 cm. The male broods the eggs for the next eight weeks and doesn’t eat during that entire time, and only drinks whatever dew he can gather from the plants around the nest without leaving the nest. A male can lose a third of his weight while brooding. Meanwhile, the female often leaves and finds another mate, sometimes laying several clutches of eggs during the nesting season.

When the babies hatch, the father takes care of them for the next six or seven months, at which point they’re fully grown. While he’s in charge, the father won’t let any other emus near the chicks, even their mother. He teaches them to find food and if the babies feel threatened, they’ll run underneath him to hide. Baby emus have gray and white longitudinal stripes and are super cute.

The emu eats plants and insects, and will sometimes travel long distances to find enough food and water. It can go a long time without eating and several days without drinking. It usually only drinks once a day but it will drink a whole lot of water during that one time.

Some populations of emu migrate to the coast after breeding season, where they can find more food and cooler weather. But in 1932 in western Australia, migrating emus didn’t find their usual food supplies. They found a whole lot of wheat fields cultivated by former soldiers, who had been given land after World War I. The Australian government had encouraged the soldiers to clear the land of native vegetation and grow lots of wheat, which they did. Then the emus showed up.

Naturally, without their usual food to eat, the emus sampled the wheat plants. And they found the plants yummy. Also, even though there was a drought that year, there was plenty of water for the wheat, which meant plenty of water for emus. So the emus showed up and showed up and showed up, an estimated 20,000 emus eating as much wheat as they could hold and crashing through fences to get to it.

The farmers sent a group to speak to the Minister of Defence to get help. The Minister of Defence sent a major with a small handful of soldiers to deal with the birds, with the soldiers armed with two lightweight machine guns.

On November 2, 1932, the men encountered their first emus. The birds were too far away to shoot so the men tried to herd them closer, but the emus scattered instead of staying in a group. Two days later, the men encountered approximately a thousand emus and lay in wait until the birds were close enough to shoot at–but the gun jammed and the birds scattered again. At this point the soldiers had killed maybe two dozen birds in all.

That was enough that the emus had figured out the men were a danger. The men reported that each group of birds now had a lookout. The rest of the flock would eat while the lookout kept watch. When the lookout spotted the men, it warned the others and all the emus would scatter.

The men even tried mounting a machine gun on a truck to run the emus down. But the ground was too bumpy to aim while the truck was moving, plus it couldn’t outrun the emus. On one occasion a dead emu got tangled in the steering equipment and the truck crashed into a fence, destroying both the truck and the fence.

On November 8, the men were withdrawn after having only killed around 200 emus, but they’d used a quarter of the ammunition they’d been allotted to do that. One politician suggested sarcastically that the soldiers deserved a medal for their part in the war, and another politician pointed out that the medal should properly go to the emus.

But the emus were still a problem, so after more entreaties from farmers, the same men and guns were sent back to try again. They kept at it for the next month or so and did manage to kill maybe a few thousand birds, but for every bird they killed, they shot ten bullets. Finally they were recalled for good. The government put a bounty on dead emus instead, and the farmers put up larger and stronger fences. It wasn’t until the late 1960s that the bounty was canceled and the emu protected. The current population is large and healthy.

There used to be several smaller subspecies of emu, but they went extinct basically as soon as Europeans showed up. We’re lucky that the mainland emu survived the war and the bounty hunting so that we can appreciate it today.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 359: The Antarctic Death Star(fish)!

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Thanks to Morgan for suggesting this week’s topic, the Antarctic Death Star!

Further reading:

Giant Monster Starfish ALERT

Echinoderm Tube Feet Don’t Suck! They Stick!

Bodies of Starfish and Other Echinoderms Are Really Just Heads, New Research Suggests

The Antarctic death star [from first link listed above]:

The “beartrap” structures, magnified [from first link listed above]:

Show transcript:

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

It’s been way too long since we talked about an invertebrate, so this week we’ll look at one suggested by Morgan, the Antarctic death star.

It has a lot of other names too, including the Antarctic sun starfish and the wolftrap or beartrap starfish. Its scientific name is Labidiaster annulatus. I’m going to call it the death star because I think that’s hilarious.

As you may have guessed from its common names, the Antarctic death star is a starfish that lives in cold ocean waters near the Antarctic, AKA the south pole. But its common names also hint at how it gets its food, and this would be a good time to take a moment and be glad you’re not a copepod that also lives in the Antarctic Ocean.

The death star is reddish-brown on its dorsal side, white underneath. It’s a large starfish, up to two feet across, or 60 cm, and it also has a lot of legs, more properly called rays—up to 50 of them. The rays are long, narrow, and very flexible, and the undersides have rows of little structures called tube feet. All echinoderms, including starfish, have these tube feet and they’re used for several purposes. One important purpose is helping the animal stick to a hard surface, which allows it to climb around more easily and right itself if it gets flipped over.

For over 150 years scientists thought the tube feet acted like little suction cups, but that didn’t explain how a starfish or other echinoderm could stick to porous surfaces. It wasn’t until 2012 that a study was published explaining how the tube feet actually work. The tube feet exude tiny amounts of a sticky chemical that acts like glue.

The death star’s body also has little spines and bumps all over it, but it also has some structures that give the animal its other names, the wolftrap or beartrap starfish. The structures are called pedicellariae [PED-uh-suh-LAIR-ee-aye], which are also common in echinoderms. Most echinoderms seem to use them to keep algae and other organisms from settling on the body, although scientists aren’t completely sure. Pedicellariae have muscles and sensory receptors, and when something touches them, they snap shut like a trap. In the case of the Antarctic death star, its pedicellariae are extra big and really sharp. When a krill or other tiny animal brushes against one of these little traps, it grabs the animal and then the death star can eat it.

But that’s just part of what’s going on when the death star goes hunting, so let’s discuss it in more detail.

Most starfish spend almost all their time on the ocean floor, walking around looking for food. The death star does this too, but not all the time. Quite often a death star will climb on top of a rock or other large structure, and then it will extend some of its rays up and out into the water. It waves its rays around and if it touches a small animal, it will wrap the rays around it. The pedicellariae also snap shut. Then the death star can eat whatever it caught. Usually this is krill or amphipods, but it’s not a picky eater. Since it will eat animals it finds already dead, researchers aren’t completely sure if the death star ever catches fish. They’ve certainly found dead fish in death star stomachs, but the water it lives in is so cold that not many fish live there anyway. Fish don’t make up a big part of the death star’s diet, whether or not it’s catching them itself. The death star also eats other starfish, including smaller death stars.

Like other starfish, the death star can eat surprisingly large pieces of food because it can evert its stomach. This means it can actually push its stomach out through its mouth and engulf whatever large food it’s found or caught. The digestion process starts right away, which allows the starfish to eat food that can’t actually fit through its mouth. It doesn’t chew its food because it doesn’t have any kind of teeth or jaws, but who needs teeth and jaws if your stomach can just reach out and grab food?

While I was researching the death star, I came across a study published in November 2023 about echinoderms, so let’s learn something surprising about starfish and their relations in general.

Echinoderms demonstrate radial symmetry instead of bilateral symmetry. That’s why you can’t tell when a starfish or other echinoderm is facing forward, because it doesn’t actually have a forward. But it’s actually more complicated than it sounds, because the distant ancestor of echinoderms, which lived during the Cambrian almost half a billion years ago, did demonstrate bilateral symmetry, and the larvae of modern echinoderms do too. When a modern echinoderm larva develops into an adult, the left side of its body is the only part that grows. The right side of its body is absorbed and from then on the body develops radially. It actually shows pentaradial symmetry, with five sections around the central part of the body. That’s why so many starfish have five rays, although obviously not all of them. The death star starts out with five rays but adds more and more as it grows.

For a long time scientists have wondered if echinoderms technically have heads or if they’re just bodies. They don’t have eyes or nostrils or most other body parts that we associate with the head, just an oral opening in the middle of the underside of the disc. Starfish do have cells at the ends of their rays that act as eyespots, which are sensitive to light and dark but can’t actually see anything else. Instead of a brain, it has a nerve ring around its mouth and connected nerve nets in its rays, and its digestive system extends into its rays.

In other words, it sure seems like an echinoderm has no head and is basically just a weird body. But the new study came to a surprising conclusion. The study examined starfish genetics and discovered that the genes associated with head development were there. It was the genes associated with the development of a body and tail that were missing. In other words, the starfish, and echinoderms in general, are just really complicated heads.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 358: The Bush Dog and the Maned Wolf

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Thanks to Dean, Mia, and Lydia for their suggestions this week!

The tayra looks kind of like a canid but is a mustelid [photo by Bob Johnson – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=85291909]:

The bush dog looks kind of like a mustelid but is a canid:

The maned wolf looks like a fox with reallllllly long legs:

Show transcript:

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

This week we have a suggestion from Dean, who wanted to learn about the bush dog. We’re actually going to learn about two animals that share the name bush dog, along with an animal suggested by both Mia and Lydia, the maned wolf.

We’ll start with the bush dog that isn’t a dog. It’s more commonly called the tayra and it’s native to much of Central and South America. It prefers to live in forests, especially tropical forests, but it will travel long distances to find food and can sometimes be found in grasslands and other areas. Despite the name bush dog, it’s not a canid at all. It’s a member of the family Mustelidae, which includes weasels, ferrets, and wolverines. The tayra has a long body and short legs, but it’s also bulkier than most mustelids, more similar to a wolverine. It can grow almost four feet long, or 1.2 meters, including its long tail, and its fur is short and black or dark brown. It also has a patch of lighter fur on its chest that’s a unique shape to every individual, sometimes called a heart patch.

The tayra is mostly active during the day and does a lot of climbing around in trees, where it eats birds, lizards and other reptiles, small mammals, eggs, fruit, honey, and large insects and other invertebrates. It especially likes plantains, which is a type of banana. The tayra will pick green plantains and hide them, then come back to eat them after they ripen. It’s also really good at catching spiny rats, so good that the indigenous peoples in various places would sometimes tame a tayra or two in order to keep spiny rats and other rodents away from their food stores.

The bush dog that is actually a canid is also from South America, but we’re going to start not with the living animal, but with an extinct one. Back in the 19th century, when it was possible to specialize in several fields of science at once, a Danish man named Peter Wilhelm Lund made a name for himself as an archaeologist, a paleontologist, and a zoologist. He moved to Brazil in South America in 1825, went back to Europe in 1829 to finish his doctoral degree, but returned to Brazil in 1832 for the rest of his life. He just really liked it there. He described hundreds of Brazilian plants and animals scientifically and is most well known for his studies of extinct ice age megafauna, along with prehistoric cave paintings.

One of the animals he described was an unusual canid. He discovered its skull in a cave in 1839, so he called it the cave wolf. That makes it sound scary and impressive, but it was actually a fairly small animal. He gave it the scientific name Speothos pacivorus, which means “cave wolf hunter.”

In 1842 Lund described a living canid with a similar skull, although its teeth weren’t as big and it was even smaller than the cave wolf. But he didn’t quite make the connection and placed the living animal in a completely different genus. In 1843 another scientist renamed the animal but again placed it in a completely different genus from the cave wolf.

It’s not unusual for an animal to be studied repeatedly and its taxonomy debated by various scientists as they try to figure out what the animal’s closest relations are. But in the case of the bush dog, it kept getting shuffled from genus to genus every few years, so that in the 180 years since it was originally described it’s been placed and re-placed in nine different genera, until it was finally renamed Speothos venaticus and recognized as a close relation, or possibly the direct descendant, of the cave wolf.

Although the bush dog’s ancestors lived in the highlands of Brazil, the bush dog alive today is adapted for forests. It has partially webbed toes that help it walk on soft soil around water, and it spends a lot of time in water. It’s brown all over, although some individuals have a patch of lighter brown fur on the throat, and its legs and tail are often darker. Puppies are black all over. Its legs are short and it has a short snout and small ears. It actually really does look similar in many ways to the other bush dog, the tayra, although its tail is shorter.

The bush dog is incredibly shy and lives in remote areas that are hard for humans to explore, so we actually don’t know a whole lot about it. It’s so shy that it’s even hard to catch on camera traps. It’s a social animal that sometimes hunts by itself and sometimes in groups, and it eats pretty much anything it can catch. Its main prey is rodents, especially large rodents like capybaras, but it also hunts peccaries, tapirs, and the large flightless bird called the rhea.

Part of the reason the bush dog kept getting moved from genus to genus is that it’s not very similar to other canids. The fact that it even looks a lot like a mustelid gives you an idea of how strange it appears. It has a cute puppy face since its snout and ears are so small, and its long chunky body and short legs make it look a little like a corgi. It’s only been recently that scientists have identified one of its closest relations, and it’s a canid you might not expect. It’s also the canid suggested by Mia and Lydia, because everyone loves the maned wolf.

We’ve talked about the maned wolf before, most recently in episode 167. The maned wolf looks kind of like a short-tailed fox with extremely long legs—like, twice as long as a regular fox’s legs or longer. But the maned wolf isn’t a fox and it isn’t a wolf, or a coyote, or a dog, or any other type of canid. It’s its own thing. It lives in the grasslands of central South America, and it needs extremely long legs to help it see over tall grass. It stands over three and a half feet tall at the shoulder, or 110 cm, while the bush dog only stands about one foot tall, or 30 cm.

The maned wolf is mostly solitary, although mated pairs will sometimes share a territory. It’s an omnivore and eats a lot of plant material in addition to hunting small animals that live in the grass. It especially likes a tomato-like fruit called the wolf apple, and it will also eat carrion. If it catches a large animal, or finds a large animal already dead, it will bury what’s left of the body to eat later. It marks the hole it digs with urine so it can more easily find it later. It also marks its territory with urine.

The maned wolf’s urine contains a chemical called pyrazine, which produces a strong smell. Since the smell of pyrazine is produced by many animals and plants that are toxic, it’s possible that having the smell in its urine helps keep other animals away from the maned wolf’s food caches and out of its territory. Humans recognize the smell of pyrazine as something else, marijuana, since the marijuana plant actually contains pyrazine. In 2006 someone at the Rotterdam Zoo in Holland complained that people were smoking marijuana in the zoo, but when police investigated, they discovered that the smell was actually coming from the maned wolf exhibit. This will never not be funny to me.

You can find Strange Animals Podcast at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast if you’d like to support us for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!