Episodes

  • Episode 389: Updates 7 and the Lava Bear

    Episode 389: Updates 7 and the Lava Bear
    Jul 15 2024
    It's our annual updates episode! Thanks to Kelsey and Torin for the extra information about ultraviolet light, and thanks to Caleb for suggesting we learn more about the dingo! Further reading: At Least 125 Species of Mammals Glow under Ultraviolet Light, New Study Reveals DNA has revealed the origin of this giant ‘mystery’ gecko Bootlace Worm: Earth’s Longest Animal Produces Powerful Toxin Non-stop flight: 4,200 km transatlantic flight of the Painted Lady butterfly mapped Gigantopithecus Went Extinct between 295,000 and 215,000 Years Ago, New Study Says First-Ever Terror Bird Footprints Discovered Last surviving woolly mammoths were inbred but not doomed to extinction Australian Dingoes Are Early Offshoot of Modern Breed Dogs, Study Shows A (badly) stuffed lava bear: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week we have our annual updates episode, and we’ll also learn about a mystery animal called the lava bear! As usual, a reminder that I don’t try to update everything we’ve ever talked about. That would be impossible. I just pick new information that is especially interesting. After our episode about animals and ultraviolet light, I got a great email from Kelsey and Torin with some information I didn’t know. I got permission to quote the email, which I think you’ll find really interesting too: “You said humans can’t see UV light, which is true, however humans can detect UV light via neuropsin (a non-visual photoreceptor in the retina). These detectors allow the body to be signaled that it’s time to do things like make sex-steroid hormones, neurotransmitters, etc. (Spending too much time indoors results in non-optimal hormone levels, lowered neurotransmitter production, etc.) “Humans also have melanopsin detectors in the retina and skin. Melanopsin detectors respond to blue light. Artificial light (LEDs, flourescents, etc) after dark entering the eye or shining on the skin is sensed by these proteins as mid-day daylight. This results in an immediate drop in melatonin production when it should be increasing getting closer to bedtime.” And that’s why you shouldn’t look at your phone at night, which I am super bad about doing. Our first update is related to ultraviolet light. A study published in October of 2023 examined hundreds of mammals to see if any part of their bodies glowed in ultraviolet light, called fluorescence. More than 125 of them did! It was more common in nocturnal animals that lived on land or in trees, and light-colored fur and skin was more likely to fluoresce than darker fur or skin. The white stripes of a mountain zebra, for example, fluoresce while the black stripes don’t. The study was only carried out on animals that were already dead, many of them taxidermied. To rule out that the fluorescence had something to do with chemicals used in taxidermy, they also tested specimens that had been flash-frozen after dying, and the results were the same. The study concluded that ultraviolet fluorescence is actually really common in mammals, we just didn’t know because we can’t see it. The glow is typically faint and may appear pink, green, or blue. Some other animals that fluoresce include bats, cats, flying squirrels, wombats, koalas, Tasmanian devils, polar bears, armadillos, red foxes, and even the dwarf spinner dolphin. In episode 20 we talked about Delcourt’s giant gecko, which is only known from a single museum specimen donated in the 19th century. In 1979 a herpetologist named Alain Delcourt, working in the Marseilles Natural History Museum in France, noticed a big taxidermied lizard in storage and wondered what it was. It wasn’t labeled and he didn’t recognize it, surprising since it was the biggest gecko he’d ever seen—two feet long, or about 60 cm. He sent photos to several reptile experts and they didn’t know what it was either. Finally the specimen was examined and in 1986 it was described as a new species.
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    18 mins
  • Episode 388: Washington’s Eagle

    Episode 388: Washington’s Eagle
    Jul 8 2024
    Further reading: Audubon's Bird of Washington: Unraveling the fraud that launched The Birds of America The Mystery of the Missing John James Audubon Self-Portrait Washington's eagle, as painted by Audubon: The tiny detail in Audubon's golden eagle painting that is supposed to be a self-portrait: The golden eagle painting as it was published. Note that there's no tiny figure in the lower left-hand corner: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This past weekend I was out of town, or to be completely honest I will have been out of town, because I’m getting this episode ready well in advance. Since July 4 was only a few days ago, or will have been only a few days ago, and July 4 is Independence Day in the United States of America, I thought it might be fun to talk about a very American bird, Washington’s eagle. We talked about it before way back in episode 17, and I updated that information for the Beyond Bigfoot & Nessie book for its own chapter. When I was researching birds for episode 381 I revisited the topic briefly and realized it’s so interesting that I should just turn it into a full episode. We only have two known species of eagle in North America, the bald eagle and the North American golden eagle. Both have wingspans that can reach more than 8 feet, or 2.4 meters, and both are relatively common throughout most of North America. But we might have a third eagle, or had one only a few hundred years ago. We might even have a depiction of one by the most famous bird artist in the world, James Audubon. In February 1814, Audubon was traveling on a boat on the upper Mississippi River when he spotted a big eagle he didn’t recognize. A Canadian fur dealer who was with him said it was a rare eagle that he’d only ever seen around the Great Lakes before, called the great eagle. Audubon was familiar with bald eagles and golden eagles, but he was convinced the “great eagle” was something else. Audubon made four more sightings over the next few years, including at close range in Kentucky where he was able to watch a pair with a nest and two babies. Two years after that he spotted an adult eagle at a farm near Henderson, Kentucky. Some pigs had just been slaughtered and the eagle was looking for scraps. Audubon shot the bird and took it to a friend who lived nearby, an experienced hunter, and both men examined the body carefully. According to the notes Audubon made at the time, the bird was a male with a wingspan of 10.2 feet, or just over 3 meters. Since female eagles are generally larger than males, that means this 10-foot wingspan was likely on the smaller side of average for the species. It was dark brown on its upper body, a lighter cinnamon brown underneath, and had a dark bill and yellow legs. Audubon named the bird Washington’s eagle and used the specimen as a model for a life-sized painting. Audubon was meticulous about details and size, using a double-grid method to make sure his bird paintings were exact. This was long before photography. So we have a detailed painting and first-hand notes from James Audubon himself about an eagle that…doesn’t appear to exist. Audubon painted a few birds that went extinct afterwards, including the ivory-billed woodpecker and the passenger pigeon, along with less well-known birds like Bachman’s warbler and the Carolina parakeet. He also made some mistakes. Many people think Washington’s eagle is another mistake and was just an immature bald eagle, which it resembles. But here’s the problem. Audubon wasn’t always truthful. He painted some birds that he never saw but claimed he did, because another bird illustrator had painted them first. Once he claimed he went hunting with Daniel Boone in Kentucky in 1810, but at that time Boone would have been in his 70s and was living several states away. Audubon also claimed that he discovered a little bird called Lincoln’s sparrow, but this wasn’t the case.
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    12 mins
  • Episode 387: The Link Between Fossils and Folklore

    Episode 387: The Link Between Fossils and Folklore
    Jul 1 2024
    Thanks to Richard from NC for inspiring this episode! Further reading: Paleontologists Debunk Popular Claim that Protoceratops Fossils Inspired Legend of Griffin The Fossil Dragons of Lake Lucerne, Switzerland The Lindworm statue: A woolly rhinoceros skull: A golden collar dated to the 4th century BCE, made by Greek artisans for the Scythians, discovered in Ukraine. The bottom row of figures shows griffins attacking horses: The Cyclops and a (damaged, polished) elephant skull: A camahueto statue [photo by De Rjcastillo - Trabajo propio, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=145434346]: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week we’re going to learn about the link between fossils and folklore, a topic inspired by a conversation I had with Richard from North Carolina. We know that stories about monsters were sometimes inspired by fossils, and we even have an example from episode 53. That was way back in 2018, so let’s talk about it again. In Klagenfurt in Austria there’s a statue of a dragon, called the lindorm or lindwurm, that was erected in 1593 to commemorate a local story. The story goes that a dragon lived near the lake and on foggy days would leap out of the fog and attack people. Sometimes people could hear its roaring over the noise of the river. Finally the duke had a tower built and filled it with brave knights. They fastened a barbed chain to a collar on a bull, and when the dragon came and swallowed the bull, the chain caught in its throat and tethered it to the tower. The knights came out and killed the dragon. The original story probably dates to around the 12th century, but it was given new life in 1335 when a skull was found in a local gravel pit. It was clearly a dragon skull and in fact it’s still on display in a local museum. The monument’s artist based the shape of the dragon’s head on the skull. In 1935 the skull was identified as that of a woolly rhinoceros. In 1989 a folklorist proposed that the legend of the griffin was inspired by protoceratops fossils. The griffin is a mythological creature that’s been depicted in art, writing, and folklore dating back at least 5,000 years, with early variations on the monster dating back as much as 8,000 years. The griffin these days is depicted as a mixture of a lion and an eagle. It has an eagle’s head, wings, and front legs, and it often has long ears, while the rest of its body is that of a lion. The griffin isn’t a real animal and never was. It has six limbs, for one thing, four legs and two wings, and it also has a mixture of mammal and bird traits. I can confirm that it’s a lot of fun to draw, though, and lots of great stories and books have been written about it in modern times. Ancient depictions of a griffin-like monster have been found throughout much of eastern Europe, the Middle East, the Mediterranean, northern Africa, and central Asia. Much of what we know about the griffin legend comes from ancient Greek and Roman stories, but they in turn got at least some of their stories from ancient Scythia. That’s important for the hypothesis that the griffin legend was inspired by protoceratops fossils. Protoceratops lived between 75 and 71 million years ago and its fossils have been found in parts of China and Mongolia. It was a ceratopsian but it didn’t belong to the family Ceratopsidae, which includes Triceratops. It grew up to about 8 feet long, or 2.5 meters, with a big skull and a neck frill, but while that sounds big, it actually was on the small size for a ceratopsian. At most it would have barely stood waist-high to an average human, so while it was heavy and compact, it was probably smaller, if not lighter, than a modern lion. It ate plants and while it had teeth, it also had a beak, sort of like a turtle’s beak. Folklorist Adrienne Mayor published a number of papers and a book in the 1990s discussing the links ...
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    14 mins
  • Episode 386: The Greater Siren and the Anhinga

    Episode 386: The Greater Siren and the Anhinga
    Jun 24 2024
    Thanks to Kai and Emily for their suggestions this week! The greater siren [photo by Kevin Stohlgren, taken from this site]: The anhinga [photo by Tim from Ithaca - Anhinga, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=15526948]: An anhinga swimming [photo by Wknight94, CC BY-SA 3.0 , via Wikimedia Commons]: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week we’re going to learn about two animals, one suggested by Kai and the other suggested by Kai’s mom Emily. It’s so awesome to hear when families like to listen to the podcast together. This episode even includes a mystery animal I bet you’ve never heard of. Let’s start with Kai’s suggestion, the greater siren. The greater siren is an amphibian, specifically a salamander, but it’s probably not the kind of salamander you’re thinking of. For one thing, it can grow over three feet long, or about a meter, which is pretty darn big for a salamander. It’s dark green or gray in color with tiny yellow or green speckles, and while it has short front legs, those are the only legs it has or needs. It also has external gills which it keeps throughout its life, unlike most salamanders who lose their external gills when they metamorphose into adults. The greater siren lives primarily in Florida, but it’s also found in coastal wetlands throughout much of the southeastern United States. It’s mostly nocturnal and during the day it hides among water plants or under rocks, and will even burrow into the mud. At night it comes out to find food, which includes crayfish and other crustaceans, insects and spiders, little fish, other amphibians, snails, and even algae. It swallows its food whole, even snails and other mollusks. It poops out the shells and other undigestible pieces. The grater siren’s body is long but thin, sort of like an eel, with a rounded tail that’s slightly flattened to help it swim. While it does spend its whole life in the water, it has small lungs that allow it to breathe air if it needs to. It can wriggle above ground for short distances if it needs to find a new pond or river, and sometimes it will sun itself on shore. In drought conditions when its water dries up, the greater siren will burrow into the mud and secrete mucus that mixes with dead skin cells to form a sort of cocoon. The cocoon covers everything but the siren’s mouth, so it can still breathe. Then it enters a state of torpor called aestivation, and it can stay in its mud cocoon for a long time, possibly as much as five years, and still be fine once the water returns. It does lose a lot of its body fat and its gills wither away, but it regenerates them quickly once it has water, and will gain weight quickly too once it has food. In early spring, the female siren lays her eggs in shallow water. The male fertilizes them and takes care of them for the next two months, when they hatch into little bitty sirens that go off on their own right away. The greater siren has tiny eyes and probably doesn’t see very well. It has a good sense of smell instead, and it can also sense movement and vibrations around it with its lateral line system. This is an organ found in many fish and a lot of larval amphibians, although the greater siren retains it throughout its life. It allows the animal to sense the movement of water in extremely fine detail. The greater siren can probably also sense electrical impulses, which is something that all animals generate when they use their muscles. If there’s a greater siren, you may be thinking, there must be a lesser siren too. There is, and it’s very similar to the greater siren, just not as big. It only grows about two feet long at most, or 61 cm. Kai mentioned that the greater siren looks a lot like the axolotl, a critically endangered salamander found only in Mexico. I checked to see if the two salamanders were closely related and was actually surprised t...
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    10 mins
  • Episode 385: More Monitors

    Episode 385: More Monitors
    Jun 17 2024
    Thanks to Cosmo and Zachary for suggesting this week's monitor lizards! Further reading: No One Imagined Giant Lizard Nests Would Be This Weird The Mighty Modifications of the Yellow-Spotted Goanna The Asian water monitor: A yellow-spotted goanna standing up [picture by Geowombats - https://www.flickr.com/photos/geowombats/136601260/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=2595566]: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. Last week we had our big dragons episode where we learned about the Komodo dragon and some of its relations, including goannas. I forgot to thank Cosmo for suggesting the lace monitor, also called the tree goanna, in that episode, and I also forgot that Zachary had also suggested monitor lizards as a topic, so let’s learn about two more monitor lizards this week. Cosmo is particularly interested in aquatic and semi-aquatic animals, and a lot of monitor lizards are semi-aquatic. Let’s learn about the Asian water monitor first, since it’s the second-largest lizard alive today, only smaller than the Komodo dragon. The Asian water monitor is common in many parts of South and Southeast Asia, including India, Vietnam, Cambodia, Laos, southern China, and many islands. A half dozen subspecies are currently recognized, although there may be more. The largest water monitor ever reliably measured was 10 1/2 feet long, or 3.2 meters. It’s dark brown or black with yellow speckles and streaks, and young lizards have larger yellow spots and stripes. It lives wherever it can find fresh or brackish water, from lakes and rivers to swamps, ponds, and even sewers. Like the crocodile, the Asian water monitor’s tail is flattened from side to side, called lateral compression, and it’s also very strong. It swims by tucking its legs against its sides and propelling itself through the water with its tail. It can dive deeply to find food, and while it prefers fresh water, it will swim in the ocean too. That’s why it’s found on so many islands. Juvenile Asian water monitors spend most of the time in trees, but even a fully grown lizard will sometimes climb a tree to escape danger. Only saltwater crocodiles and humans kill the adults. In some parts of its range, the water monitor is killed by humans for its meat and its skin, which is used as leather. In other parts of its range, it’s never bothered since it eats venomous snakes and animals that damage crops. It’s sometimes kept as a pet, although it can grow so big that many people who buy a baby water monitor eventually run out of room to keep it. That’s how so many have ended up in the waterways of Florida and other areas far outside of its natural range, from people letting pets go in the wild even though doing so is illegal and immoral. While most of the time the water monitor isn’t dangerous to humans, if it feels threatened, it can be quite dangerous. Like the Komodo dragon and other monitor lizards, it’s venomous, plus its teeth are serrated, its jaws are strong, and it has sharp claws. It eats a lot of carrion, along with anything it can catch. A population in Java even enters caves to hunt bats that fall from the ceiling. Zachary didn’t suggest a particular type of monitor lizard, so let’s learn about the yellow-spotted goanna. Goannas are a type of monitor lizard found in Australia, New Guinea, and some nearby areas. We talked about some of them last week, including Cosmos’s suggestion of the lace monitor, but after the episode was released I found an article I had saved over a year ago. It’s about the yellow-spotted goanna, and a remarkable discovery about how it takes care of its eggs. The yellow-spotted goanna lives in parts of Australia and southern New Guinea, and a big male can grow up to five feet long, or 1.5 meters. It can swim and climb trees when it wants to, but mainly it stays on the ground, although it prefers to live near water if possible.
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    9 mins
  • Episode 384: Dragons Revisited

    Episode 384: Dragons Revisited
    Jun 10 2024
    This week we need to thanks a bunch of listeners for their suggestions: Bowie, Eilee, Pranav, and Yuzu! Further reading: Elaborate Komodo dragon armor defends against other dragons Giant killer lizard fossil shines new light on early Australians A New Origin for Dragon Folklore? The Wyvern of Wonderland The Komodo dragon: The beautiful tree goanna: The perentie: Fossilized scale tree bark looks like reptile scales: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week we’re going to revisit a popular topic we talked about back in episode 53. That episode was about dragons, including the Komodo dragon. Since then, Bowie has requested to learn more about the Komodo dragon and Eilee and Pranav both suggested an updated dragon episode. We also have a related suggestion from Yuzu, who wants to learn more about goannas in general. We’ll start with the Komodo dragon, which gets its name because it’s a huge and terrifying monitor lizard. It can grow over 10 feet long, or 3 meters, which means it’s the biggest lizard alive today. It has serrated teeth that can be an inch long, or 2.5 cm, and its skin is covered with bony osteoderms that make it spiky and act as armor. Since the Komodo dragon is the apex predator in its habitat, it only needs armor to protect it from other Komodo dragons. Fortunately for people who like to hike and have picnics in nature, the Komodo dragon only lives on four small islands in Indonesia in southeast Asia, including the island of Komodo. Young Komodo dragons have no armor and spend most of the time in trees, where they eat insects and other small animals. As the dragon gets older and heavier, it spends more and more time on the ground. Its armor develops at that point and is especially strong on the head. The only patches on the head that don’t have osteoderms are around the eyes and nostrils, the edges of the mouth, and over the pineal eye. That’s an organ on the top of the head that can sense light. Yes, it’s technically a third eye! The Komodo dragon is an ambush predator. When an animal happens by, the dragon jumps at it and gives it a big bite from its serrated teeth. Not only are its teeth huge and dangerous, its saliva contains venom. It’s very good at killing even a large animal like a wild pig quickly, but if the animal gets away it often dies from venom, infection, and blood loss. Like a lot of reptiles, the Komodo dragon can swallow food that’s a lot bigger than its mouth. The bones of its jaws are what’s called loosely articulated, meaning the joints can flex to allow the dragon to swallow a goat whole, for instance. Its stomach can also expand to hold a really big meal all at once. After a dragon has swallowed as much as it can hold, it lies around in the sun to digest its food. After its food is digested, which can take days, it horks up a big wad of whatever it can’t digest. This includes hair or feathers, horns, hooves, teeth, and so on, all glued together with mucus. A Komodo dragon eats anything it can catch, and the bigger the dragon is, the bigger the animals it can catch. One thing Komodo dragons are just fine with eating are other Komodo dragons. As we mentioned a few minutes ago, the Komodo dragon is a type of monitor lizard, and there are lots of monitor lizards that live throughout much of the warmest parts of the earth, including Australia. Yuzu suggested we talk about the goanna, which is the term for monitor lizards in the genus Varanus, although it’s also a term sometimes used for all monitor lizards. Goannas are more closely related to snakes than to other types of lizard. Like the Komodo dragon, the goanna will eat pretty much any animal it can catch, and will also scavenge already dead animals. Smaller goannas mostly eat insects, especially the tiny goanna often called the short-tailed pygmy monitor or just the pygmy monitor.
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    16 mins
  • Episode 383: The Marsupial Mole

    Episode 383: The Marsupial Mole
    Jun 3 2024
    Thanks to Catherine and arilloyd for suggesting the marsupial mole! Further reading: Northern marsupial mole: Rare blind creature photographed in Australian outback The marsupial mole, adorable little not-mole from Australia [photo from article above]: Grant's golden mole, adorable little not-mole from Africa: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week we have a little short episode about a very small Australian animal suggested by two listeners: Catherine, who has the best name ever, and someone called arilloyd who left us a nice review and suggested this animal in the review. I’m not sure I’m pronouncing their name right, so apologies if not. The animal is the unusual but very cute marsupial mole. There are two closely related species of marsupial mole, one that lives farther north than the other. They look very similar, with silky golden fur, strong, short legs with strong claws for digging, a very short tail, no external ears, and no eyes. The marsupial mole doesn’t have eyes at all. It doesn’t need eyes because it spends almost its entire life underground. All this sounds similar to other moles, but the marsupial mole isn’t related to other moles. Other moles are placental mammals while the marsupial mole is a (guess, you have to guess), right, it’s a marsupial! That means its babies are born very early and crawl into the mother’s pouch to finish developing. The marsupial mole has two teats, so it can raise two babies at a time. The marsupial mole grows around 6 inches long, or about 16 cm, and is a little chonky animal with a pouch that faces backwards so sand won’t get in it. It has a leathery nose and small teeth, and its front feet are large with two big claws. We actually don’t know very much about the marsupial mole because it’s so seldom seen. Not only does it live underground, it lives in the dry interior of Australia, the Great Sandy Desert. It probably also lives in other desert areas of Australia. Scientists think the marsupial mole originally evolved to dig not in desert sand but in the soft, wet ground in rainforests. Over millions of years Australia became more and more dry, until the rainforests eventually gave way to the current desert conditions. The marsupial mole had time to adapt as its environment changed, and now it’s extremely well adapted to living in sand. It sort of swims through the sand using its big paddle-shaped front feet, kicking the sand behind it with its back legs. Unlike other moles, the marsupial mole doesn’t dig permanent tunnels and the sand just collapses behind it. While the marsupial mole can’t see, and probably doesn’t have great hearing by our standards, it does have a good sense of smell in order to sniff out insect eggs and larvae, worms, and other small, soft food. It probably searches mainly for insect nests where it can find lots of food at one time, like ant nests. There are also reports of it eating adult insects, seeds, and even small lizards. The reason the marsupial mole looks and acts so much like placental moles is due to convergent evolution. The mole’s body shape and habits just work really well for an animal that wants to dig around and eat grubs. Like other moles, it has trouble regulating its body temperature since most of the time it doesn’t need to do so. If it gets too hot, it can dig deeper into the sand where it’s cooler. The marsupial mole is most similar to a completely unrelated placental mammal, Grant’s golden mole, which lives in a few parts of coastal South Africa and Namibia in Africa. Grant’s golden mole lives in sandy areas and swims through the sand like the marsupial mole does. It mainly eats termites and other insects, but it will also eat small reptiles. Its fur is a sandy golden color and it has no external ears, no eyes, and three big claws on its front feet. It only grows about 3 and a half inches long, or 9 cm, which makes it the smallest golden mole.
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    7 mins
  • Episode 382: Smilodon, the Sabertoothed Cat

    Episode 382: Smilodon, the Sabertoothed Cat
    May 27 2024
    Thanks to Luke for suggesting this week's topic: Smilodon, the saber-toothed cat, AKA the sabertooth tiger! Further reading: Did sabertooth tigers purr or roar? The double-fanged adolescence of saber-toothed cats We don't know for sure what Smilodon looked like, but it might have been something like this: An artist's rendition of an adolescent Smilodon with doubled fangs [picture from second link above]: Show transcript: Welcome to Strange Animals Podcast. I’m your host, Kate Shaw. This week we’re going to learn about an animal suggested by Luke, the sabertooth tiger, also called the sabertooth cat since it wasn’t actually a tiger, also called smilodon after its scientific name. We’ve talked about it before, way back in episode 34, but a lot of new studies have been published since then and we know a lot more about this terrifying-looking animal! The genus of the saber-toothed cat is Smilodon, so that’s mostly what I’m going to call it in this episode. It’s classified as a member of the family Felidae, which is the same family where you find domestic cats, wildcats, big cats, and lots of extinct animals like the cave lion, but Smilodon wasn’t closely related to what we think of as cats. There were at least three species of saber-tooth cats in the genus Smilodon that we know of, but it had many other similar-looking relatives. Smilodon is best known from the La Brea tar pits in Los Angeles, California, where the remains of hundreds of individuals have been discovered. That’s a big reason why we know so much about Smilodon, especially the species Smilodon fatalis that lived in North America and parts of South America. An even bigger species lived exclusively in South America, while both were probably descended from a smaller species that also lived in South America. S. fatalis is estimated to have grown up to 39 inches tall at the shoulder, or 99 cm, while S. populator stood at an estimated 47 inches tall, or 119 cm. That’s almost four feet tall. Some full-grown humans are that height! Smilodon was so stocky and heavily muscled that it probably looked more like a bear than a cat. Its had a broad head and jaws that could open much wider than most modern animals, which allowed it to deploy its most deadly weapon, its saber teeth, without its jaw getting in the way. Smilodon’s saber teeth were as much as 11 inches long, or 28 cm, although S. fatalis typically had teeth around 8 inches long, or 20 cm. Big as they were, the saber teeth were also relatively delicate. A young Smilodon didn’t start growing its big teeth until it was about a year old, and even then it had to learn how to use them so they wouldn’t break. Luckily for adolescent smilodons, they didn’t lose their baby fangs until they were fully grown. Most mammals only grow two sets of teeth in our lifetimes. The first set is usually called baby teeth or milk teeth. As the baby grows up, its adult teeth start growing in one at a time. The adult tooth pushes at the baby tooth until it gets loose and either comes out on its own or, in the case of me in second grade, I asked to go to the bathroom and then spent half an hour twisting at a loose baby tooth until it finally came out, along with some blood. But I got a quarter that night from the tooth fairy. (Kids, maybe don’t do that.) In the case of a young smilodon’s saber teeth, they grew in just next to the baby fangs. Instead of pushing the baby fangs out, the new teeth grew alongside them and even had a groove for the baby teeth to fit into. When scientists first discovered preserved jaws with these double fangs, they thought it was a fluke, that sometimes the new teeth came in wrong and didn’t push the old teeth out. That happens in humans sometimes too and then you have to go to the dentist to get the old baby teeth taken out. But paleontologists kept finding these double toothed jaws, and only in adolescent smilodons. Finally a team of scientists studied the teeth carefully and made...
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    9 mins