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Literally speaking, the coolest bug on Earth is a wingless fly called the Antarctic midge. And that's not up for debate—because it's the only insect that lives exclusively in the coldest place on the planet: Antarctica.

And even though it's not easy to carve out a habitat there, the midge has some special tricks that make this frigid continent the perfect home. In general, Antarctica is a terrible place to live. Average air temperatures are well below freezing, and the cold, dry wind makes it easy to get dehydrated.

It's especially tough for insects, which are cold-blooded like reptiles, so they /need/ warmth from the outside, or they can't really move around. To make matters worse, the ozone layer is really thin in that part of the world, so. UV radiation just beams down on the Earth—which can mess up DNA and be deadly for insects.

So it might not be /your/ first pick for a home, but for the Antarctic midge, it's perfect. This insect has been around for over 30 million years, and along the way, it's evolved a bunch of adaptations to help it survive. First of all, it's a fly that can't fly—because there'd be no point with Antarctica's winds, so it doesn't even have wings.

And that comes with a perk: Since wings let off a lot of heat, being wingless helps midges retain what little warmth they have. The insects also huddle together, which helps keep them from losing too much water to Antarctica's frigid, dry air. And it's also kind of cute.

But they're still in /Antarctica/, so there's only so much they can do to stay warm. They /also/ need ways to just deal with being cold. Like many insects, midges have special tricks to survive their blood freezing over.

They do this through a process called cold hardening, where they make special chemicals that protect their cells from being damaged if their bodies /form ice on the inside/. …because that's a thing that happens in Antarctica. They also have what are called heat shock proteins, which are thought to fix other proteins that lose their shape under stress—like when they're exposed to UV rays or extreme cold—so that they can function properly. The insect also takes advantage of an unusual life cycle to make it through the coldest parts of the year.

See, adult midges only live for 10 days, but they stay in their larval form for /two years/. That lets them take advantage of two summer feeding seasons, so they can fatten up enough to reproduce. When it's time, they emerge in their adult form all at once, find a mate, and get down to business.

And while this lifestyle doesn't make Antarctica sound like a paradise, these strategies work really well for the midge. In fact, at about half a centimeter long, these insects are the biggest land animal on the whole continent. Penguins, for the record, are technically /marine/ animals, so they don't count.

And the Antarctic midge has accomplished all of this with the tiniest genome of any known insect. Meaning it's not actually all that complex. In fact, while these adaptations do help the midge survive its extreme habitat, a /lot/ of these mechanisms already exist in other insects.

So scientists are still trying to figure out what makes the Antarctic midge so special—if it's just better at /using/ the survival features that many insects have, or whether it has something else going for it. Either way, the better we understand this strange, hardy insect, the better we can understand the Antarctic ecosystem as a whole. Thanks for watching this episode of SciShow!

And while you're here, I want to tell you about our Pin of the Month. It's of the Mars Express spacecraft, which is currently orbiting around Mars looking for water below the surface. To order the pin, check out the link in the description.

And to find out more about this spacecraft, you can watch our episode on it over at SciShow Space. [ ♪OUTRO ].