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Literally speaking, the coolest bug on Earth is a wingless fly called the Antarctic midge.
毫不夸张的说，地球上最酷的昆虫是一种没有翅膀的虫子——南极蠓。
And that's not up for debate—because it's the only insect that lives exclusively in the coldest place on the planet: Antarctica.
毫无争议——因为它是唯一一种只生活在地球最冷的地方——南极洲的昆虫。
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.
尽管在这里建立栖息地并不容易，蠓有一些独特技巧，能把这个寒冷的大陆变成完美的家。
In general, Antarctica is a terrible place to live.
通常，南极洲并不是一个好的居住地。
Average air temperatures are well below freezing, and the cold, dry wind makes it easy to get dehydrated.
平均气温低于冰点，冰冷干燥的风很容易让人脱水。
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.
对那些冷血的昆虫，如爬行动物尤为艰难，所以它们需要来自外部的温度，否则就不能移动。
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—
更糟糕的是，南极洲的臭氧层很薄，所以紫外线会直接照下来——
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.
会破坏DNA，对昆虫来说是致命的。所以，这或许作为家而言，它不是你的第一选择，但对于南极蠓，它是完美的。
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.
这种昆虫已经生存了超过3000万年，在此过程中，它进化出了一系列的适应能力来帮助它生存下来。
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.
首先，它不能飞——因为在南极洲的风中，翅膀是没有意义的，所以它没有翅膀。
And that comes with a perk: Since wings let off a lot of heat, being wingless helps midges retain what little warmth they have.
并且这还有额外的好处：由于翅膀会释放大量热量，没有翅膀帮助蠓保留它们的那一点点热量。
The insects also huddle together, which helps keep them from losing too much water to Antarctica's frigid, dry air.
这些昆虫还会挤在一起，帮助防止它们因为南极洲寒冷干燥的空气而失去太多的水分。
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.
这样有点可爱。但它们生活在南极洲，所以为了保暖，它们能做的只有这么多。
They also need ways to just deal with being cold. Like many insects, midges have special tricks to survive their blood freezing over.
它们也需要处理寒冷的方法。和很多昆虫一样，蠓拥有特殊的技巧来抵御血液结冰。
They do this through a process called cold hardening,
它们通过冷却硬化这一过程达到此目的，
where they make special chemicals that protect their cells from being damaged if their bodies form ice on the inside.
在此过程中，它们制造特殊化学物质来保护它们不会因身体结冰而受到伤害。
Because that's a thing that happens in Antarctica.
因为在南极洲会发生这样的事情。
They also have what are called heat shock proteins, which are thought to fix other proteins that lose their shape under stress—
它们还有所谓的热激蛋白，被认为可以修复其他因压力而变形的蛋白质——
like when they're exposed to UV rays or extreme cold—so that they can function properly.
比如当它们暴露于紫外线或极端寒冷——让它们能够正常运行。
The insect also takes advantage of an unusual life cycle to make it through the coldest parts of the year.
这种昆虫还利用一种不同的生命周期以熬过一年当中最寒冷的时期。
See, adult midges only live for 10 days, but they stay in their larval form for two years.
成年蠓只能存在10天，但它们可以保持幼虫形态两年。
That lets them take advantage of two summer feeding seasons, so they can fatten up enough to reproduce.
这样它们就可以充分利用两个夏季的捕食季节，这样它们就可以长得足够肥以繁殖后代。
When it's time, they emerge in their adult form all at once, find a mate, and get down to business.
到了时候，它们会立刻以成年的形式出现，找个伴侣，开始干正事。
And while this lifestyle doesn't make Antarctica sound like a paradise, these strategies work really well for the midge.
虽然这种生活方式并不能把南极洲变成天堂，但这些策略对蠓是真的有用的。
In fact, at about half a centimeter long, these insects are the biggest land animal on the whole continent.
实际上，这些昆虫大约有半厘米长，是整个大陆上最大的陆地动物。
Penguins, for the record, are technically marine animals, so they don't count.
郑重声明，企鹅不算，因为它们是海洋动物。
And the Antarctic midge has accomplished all of this with the tiniest genome of any known insect.
南极蠓用已知昆虫最小的基因完成了所有这些工作。
Meaning it's not actually all that complex. In fact, while these adaptations do help the midge survive its extreme habitat,
这意味着整个过程其实没有那么复杂。事实上，虽然这些适应能力确实帮助蠓在这个极端栖息地生存，
a lot of these mechanisms already exist in other insects.
但很多这样的机能已经存在于其他昆虫中。
So scientists are still trying to figure out what makes the Antarctic midge so special—
所以科学家还在尝试弄清楚，是什么让南极蠓如此特别——
if it's just better at using the survival features that many insects have, or whether it has something else going for it.
是它更善于利用许多昆虫都有的生存特征，还是它有其他的优势。
Either way, the better we understand this strange, hardy insect, the better we can understand the Antarctic ecosystem as a whole.
不管怎样，我们越了解这种奇怪而又顽强的昆虫，就越能更好地了解整个南极生态系统。
Thanks for watching this episode of SciShow! And while you're here, I want to tell you about our Pin of the Month.
感谢收看本期节目！既然大家看到了这里，我想讲讲我们的《Pin of the Month》。
It's of the Mars Express spacecraft, which is currently orbiting around Mars looking for water below the surface.
是关于火星快车号的，该飞船目前正在绕火星轨道运行，寻找地表以下的水。
To order the pin, check out the link in the description.
点击下方链接以了解更多。
And to find out more about this spacecraft, you can watch our episode on it over at SciShow Space.
更多关于飞船的信息，可以观看《SciShow Space》的节目。
