Placeholder Image

字幕列表 影片播放

  • Thanks to Brilliant for supporting this episode of SciShow.

  • Go to Brilliant.org/SciShow to check out their Knowledge and Uncertainty course!

  • [♩ INTRO]

  • No one wants to be eaten.

  • That's why the animal world is full of adaptations to stop predatorslike hard shells, bright

  • markings, and painful stings.

  • Still, most creatures regularly end up on someone's menuexcept for velvet ants.

  • These little insects combine a ton of defenses into one very unappetizing package.

  • And they're so terrifying that pretty much nothing eats them!

  • Velvet ants aren't technically ants; they're wasps.

  • The males can fly, but the females don't have wings.

  • What they do have is a massive stinger!

  • In fact, relative to their size, they've got the longest stinger of any wasp!

  • And some seriously painful venom, too.

  • Still, they don't rely on it alone to deter predators.

  • They also have a super-tough exoskeleton.

  • It takes about five times the force to crush a velvet ant as it does to squish a bald faced

  • hornet, for example.

  • Plus, they're round and slippery, making them hard to bite down onsomething researchers

  • realized firsthand while trying to crush these things.

  • The critters kept slipping out of their grasp!

  • Of course, the velvet ant doesn't want it to come to that.

  • So, they employ an array of warning signals.

  • Theirvelvetsections are brightly colored, as a bold, visual aposematic signal.

  • They also literally sound the alarm by rubbing a section of their abdomen to make a loud

  • squeaking noise.

  • And they can release smelly alarm pheromones!

  • These by themselves can deter some predators.

  • And the combinations of defenses and warnings is super effective; it seems to train other

  • animals not to mess with them, too.

  • Like, in one experiment, lizards that had a run in with a velvet ant still avoided them

  • over a year later.

  • And in another, birds were wary of eating one of their favorite tasty treats simply

  • because researchers had painted them to look like velvet ants.

  • Predators don't even need to have encountered a specific species of them.

  • Many velvet ants mimic each others' coloring, in what scientists callllerian mimicry.

  • So if a predator encounters one, they're unlikely to mess with any of the others!

  • In fact, scientists have set up showdowns between velvet ants and many potential predators,

  • just to see what bites.

  • They tried spiders, lizards, actual ants, birds, moles, gerbils, shrews...

  • Almost all of them avoided the velvet ants entirely.

  • And the few that did catch them mostly spat them up!

  • As far as anyone can tell, toads are the only animals that occasionally eat velvet ants.

  • But they don't have an easy time of it.

  • They swallow their food whole, and velvet ants can survive for over 20 minutes inside

  • a toad's stomach!

  • So even toads end up spitting them out more often than not.

  • Velvet ants' extreme investment in defense likely has something to do with their lifestyle.

  • Females can't fly away from predators.

  • Plus they spend lots of time on the ground looking for places to lay their eggs.

  • SeeThese ants are parasites.

  • To reproduce, they find nests of other bees and wasps and lay their eggs inside.

  • When the larvae hatch, they feed on the other species' helpless young.

  • Oh, also: those nests are often well-defended by other stinging insects.

  • So I guess if you're regularly that rude to your neighbors, you'd better be as tough

  • as a velvet ant!

  • We humans will never be as hardcore as velvet ants.

  • But we can master some hardcore STEM skills with a little help from Brilliant!

  • Brilliant offers dozens of engaging, interactive courses in math, science, and computer science.

  • For example, their Knowledge and Uncertainty course teaches cutting edge math like information

  • theory and bayesian networks, but in a super fun waylike by solving puzzles!

  • And right now, if you're one of the first 200 people to sign up for an annual premium

  • subscription at Brilliant.org/SciShow, you'll get 20% off!

  • Which is a pretty sweet deal.

  • [♪ OUTRO]

Thanks to Brilliant for supporting this episode of SciShow.

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B2 中高級 美國腔

無所不能的昆蟲:認識天鵝絨螞蟻。 (The Insect Nothing Messes With: Meet the Velvet Ant)

  • 5 2
    Miho Ishii 發佈於 2021 年 01 月 14 日
影片單字