Subtitles section Play video Print subtitles {♫Intro♫} Names are important. They help us identify people and things, and to categorize our world. And in biology, they can help us understand important details about a living thing, like where it lives, or what other living things it's most closely related to. But sometimes, the common names we use for things are just…they're not just bad, they're wrong. The cool thing, though, is even those names—wrong as they may be—can still show us a lot about how we think about living things. They can reveal what traits of an animal we find most important, or how our understanding of the relatedness between living creatures has developed over time. So even the most terrible names for things can be kind of enlightening when you dive deeper into understanding why the names are so wrong. Let's start with the mountain chicken, which isn't a chicken. It's not even a bird. It's a frog. A brown, banded and splotched frog that lives on a couple islands in the Lesser Antilles. I guess you could say they live in the mountains, though they're found from sea level to about four hundred meters in altitude, not the peaks of the islands. There does seem to be a somewhat reasonable explanation for the chicken part, though: their taste. You see, mountain chickens were a prized delicacy for the people of Montserrat and Dominica. Adult females can be up to twenty-one centimeters long, while the males are slightly smaller. So each has lots of juicy frog flesh to offer, if you're into that. And apparently they do taste like chicken. But the name could also come from their distinctive chicken-like call that echoes through the steep sides of valleys where they live. Or, where they used to live, anyway. People once harvested thousands of these frogs yearly. But then the fungal disease chytridiomycosis hit Dominica in 2002 and Montserrat in 2009. That brought their numbers down from thousands to just two. With the arrival of the disease, each island enacted a permanent hunting ban—in 2003 on Dominica, and 2014 on Montserrat. And since then, the population has steadily risen. It now sits at around one hundred thirty-two, total, which is more than two, but still so very few, which is why the species continues to be considered critically endangered. So we had a chicken that was a frog, and now we've got the horny toad that isn't a toad, it's a group of spiny lizards in the genus Phrynosoma. This is one of those cases where the common name is based more on looks than scientific classifications. See, a couple of features make them stand out from other lizards—and they also explain why they're named after a puffy amphibian. For one, their body shape is flattened top to bottom, which gives them a more rounded appearance. They also have short, bent legs. And they're reluctant to run away from predators. Instead, they puff themselves up when threatened, making them look even more toad-like. They're not trying to look like a toad, though—they're making use of their most striking feature: their spikes. These sharp spikes cover most of its body but are particularly big at the back of their heads. And when they puff themselves up, they basically turn their bodies into big medieval flails. The idea is to make them look so big and dangerous that predators, especially those that like to eat their prey whole, will not be interested. If approached, they'll toss their heads backwards to pierce their attacker and direct them towards less vital parts of their body, like their tail. And if the attack continues, these not-toads have one more gruesome trick: They can squirt blood directly from their eyes. They do this by increasing the blood pressure in their head so blood escapes through the orbital sinus—a little air cavity near their eyeball. The double whammy of ouch and gross can give them enough time to run away and avoid becoming a meal. True to this list thus far, the slowworm of Europe and Russia is not a worm, despite its long body and burrowing habits. It's definitely a vertebrate and not some kind of annelid. Germans actually call them Blindschleiche or shining snakes, which is a bit closer, but they're not snakes, either. They're actually legless lizards! Slowworms have several tell-tale lizard features, like their blinking eyelids and ability to get rid of —and then regrow—their tails. That tail-dropping ability is what gave them the Latin name fragilis, meaning fragile. But this lizard is no china doll. Tail-dropping is actually a clever defense mechanism. By giving a would-be predator a snack or distraction, the lizard has the chance to run away with its vital bits intact. Regrowing their tails is a slow process, as only about five millimeters grows over two weeks. But that's not where the slow in their names comes from. That's mostly an accident of linguistics. You see, in Old English, they were called slawyrms. Over time, sla became slow, but in Old English, it doesn't mean the opposite of fast. We're not a hundred percent sure whether it was supposed to be slā with a diacritic, which meant earthworm, or sla, without the little line over it, which was a general term for venomous bitey or stingy things. Though we do know wyrm, with a Y, referred to both worms and elongated reptiles—hence the use of it nowadays to refer to serpent-y dragons. So you could translate the Old English name to “earthworm-y elongated reptile”—which is pretty accurate. Or it may have been “venomous elongated reptile”, which isn't so accurate because they're not considered venomous, but hey, at least they got the taxonomic class right. It seems like we call pretty much any long, noodly creature a worm. Take the silkworm for example, which isn't a worm at all but the larval stage of the silkworm moth. At least the silk part of its name is right. When they reach the end of the caterpillar part of their life cycle, these little guys spin cocoons made of silk proteins. Actual worms can't do that. And these so-called worms don't mess around when it comes to making silk. They can spin an average of nine point four to nine point six millimeters of the stuff every second. That's why around ninety-nine percent of the world's silk supply comes from the mouths of one particular silkworm species—Bombyx mori. And that silk is not just for fancy scarves and blouses. There are lots of applications in chemical and medical fields, too. The reason silk is so useful is that it's a protein polymer that can be transformed into different materials by dissolving it in a salt solution or adding enzymes. In fact, we loved silkworm silk so much that we domesticated the species that makes it. And the species has been so altered by centuries of artificial selection that it can't survive without our help. The adult moths can't even fly! You'd be forgiven for mistaking red pandas as pandas because of their bamboo-eating habits. But they're actually in a class of their own. Or, a family, anyway. Red pandas belong to the family Ailuridae, which is often classified as part of the weasel superfamily Musteloidea. Classifying red pandas based on who they're most related to has proven difficult because they share a lot of physiological features with other groups. The common name 'panda' was suggested when the animal was presented to the western scientific community back in 1821—because they eat bamboo. And they also have other panda-ish traits. For example, they have a pseudo-thumb—a lump of modified wrist bone—which helps them grasp bamboo like their giant panda counterparts. But they look very different from pandas in other ways—like, the shape of their head and teeth, and their stripy tail. And those are why, in 1825, they were officially classified as part of the raccoon family. But having similar physical traits doesn't always mean two things are closely related. So about a century and a half later—with the help of DNA evidence—red pandas were lumped back in with bears again. And still, that placement wasn't quite right. Additional genetic evidence now suggests they're more closely related to weasels, but are probably distinct enough to be their own family. And that makes sense because they have some really special features, that don't show up other places. Like their super flexible ankles and rotating fibulas—or shin bones—that let them climb head-first down trees. Animals aren't the only living things we're terrible at naming. Lots of plants also have bad names. Like strawberries. They are not straw, and they are not even berries, botanically speaking. See, to botanists, categories of fruit like berries have strict definitions based on what parts are fleshy and how the fruit forms. On the texture front, berries need to be squishy throughout. That is, the three layers that surround the seed—the endocarp, mesocarp, and exocarp—all have to be soft. And that is true of strawberries, so at least they meet some berry criteria. But what makes them not berries is how they form. All fruits form from the ovaries of flowers, which sit at the base of female reproductive organs called pistils. Plants can have different numbers of flowers or multiple pistils in each flower. But berries, by definition, are a simple fruit meaning they develop from one ovary in one flower. Strawberries come from flowers that have many ovaries in them, making them an aggregate fruit. They're basically like raspberries...which are also not berries. What do count as true berries are blueberries, grapes, and, weirdly enough, bananas. And of course, none of this changes what we call these things, and it's not gonna change what I'm putting in my berry muffins, either On the subject of culinary misnomers, let's talk about walnuts. Yup, you guessed it—they're not nuts... or walls… I guess. Remember how berries had to be fleshy throughout? Well, nuts, by definition, aren't fleshy at all. They're dry fruits characterized by a super thick, hard exocarp. And they're indehiscent, meaning they don't open up to shed their seeds. Walnuts are a different kind of fruit sometimes called a drupe, where the endocarp is hard, the exocarp is thin, and the mesocarp in between is fleshy or fibrous. I know what you're thinking—that doesn't really sound like the whole walnuts you can buy at the store. That's because those walnuts are actually just the hard endocarps. On the tree, walnuts have a fleshy, soft casing. We just don't see it most of the time because that casing is removed before they get to supermarket shelves. So I guess the lesson is you shouldn't name a nut by its cover...or the exterior you see at the store, anyway. Last but not least, we have the Snake Lily—which is a pretty nice name. It's definitely nicer than some of its other names, like devil's tongue, or its Latin name, which translates to misshapen penis. All these names come from its distinctive spadix—the floral spike in the middle of the flower—which kind of resembles a snake or… other things. Trouble is, this plant is neither a snake, which you would have expected, nor a lily. Lillies are flowers from the genus Lilium, which were originally classified based on their many, scale-like leaves, and their upright stems and flowers. Snake lilies might have gotten lumped in with true lilies because of how similar they look