What's the worst bug on the planet?
地球上最可恶的虫子是什么？
You might vote for the horsefly or perhaps the wasp,
你可能会说马蝇或者黄蜂，
but for many people, the worst offender is by far the mosquito.
但是对很多人来说，最可恶的莫过于蚊子。
The buzzing, the biting, the itching, the mosquito is one of the most commonly detested pests in the world.
它的嗡嗡声，它会咬人，它带来的奇痒无比，蚊子是这个世界上最遭人恨的害虫之一。
In Alaska, swarms of mosquitos can get so thick that they actually asphyxiate caribou.
在阿拉斯加，成群的蚊子之密密麻麻甚至可以使驯鹿窒息。
And mosquito-borne diseases kill millions of people every year.
而由蚊子导致的疾病每年都会夺去数百万人的性命。
The scourge that is the mosquito isn't new.
给我们带来诸多烦恼的蚊子并非什么新物种。
Mosquitoes have been around for over a hundred million years
蚊子已经存在了超过一亿年，
and over that time have coevolved with all sorts of species, including our own.
在这个过程中，它跟其他各种各样的物种一起共同进化，其中也包括我们人类。
There are actually thousands of species of mosquitos in the world,
地球上存在着数千种蚊子，
but they all share one insidious quality: they suck blood, and they're really, really good at sucking blood.
不过它们都有一个共同的邪恶特征：它们吸血，而且它们非常、非常擅长吸血。
Here's how they do it. After landing, a mosquito will slather some saliva onto the victim's skin,
看看它们是怎样做的吧。找到落脚点之后，首先它会在受害者的皮肤表面涂上大量的唾液，
which works like an antiseptic, numbing the spot so we don't notice their attack.
这些唾液起到防腐剂的作用，它可以麻醉即将被叮咬的部位而使我们毫无知觉。
This is what causes the itchy, red bumps, by the way.
对了，这些唾液也正是被蚊子咬过之后会起又痒又红的肿块的原因。
Then the bug will use its serrated mandibles to carve a little hole in your skin,
接着，它用它锯齿状的颚在你的皮肤上戳出一个小破口，
allowing it to probe around with its proboscis, searching for a blood vessel.
以便它可以用吻管探测周围，来寻找血管。

When it hits one, the lucky parasite can suck two to three times its weight in blood.
当它找到的时候，这个幸运的“食客”可以吸取达到它的身体重量两到三倍的血液。
Turns out we don't really like that too much.
当然，我们非常不喜欢被蚊子叮。
In fact, humans hate mosquitos so much that we spend billions of dollars worldwide to keep them away from us
事实上，我们人类非常痛恨蚊子，全世界花费数十亿美元来使它们能离我们远远的，
from citronella candles to bug sprays to heavy-duty agricultural pesticides.
从香茅油驱蚊蜡烛，到除虫喷雾，到高强度的农业杀虫剂。
But it's not just that mosquitos are annoying, they're also deadly.
这不仅仅是因为蚊子非常烦人，也因为它们还可以致命。
Mosquitos can transmit everything from malaria to yellow fever to West Nile virus to dengue.
蚊子可以传播各种疾病，包括疟疾、黄热病、西尼罗河病毒以及登革热。
Over a million people worldwide die every year from mosquito-borne diseases, and that's just people.
全球每年有超过100万人死于由蚊子传播的疾病，而这只是人类。
Horses, dogs, cats, they can all get diseases from mosquitoes too.
马，狗，猫，它们也会感染蚊子传播的疾病。
So, if these bugs are so dastardly, why don't we just get rid of them?
那么，既然这些蚊子如此邪恶，为什么我们不把它们彻底消灭呢？
We are humans after all, and we're pretty good at getting rid of species.
毕竟我们是人类啊，我们很擅长让物种灭绝。
Well, it's not quite so simple.
可是事情并没有那么简单。
Getting rid of the mosquito removes a food source for lots of organisms, like frogs and fish and birds.
消灭蚊子也意味着消灭很多物种的食物来源，比如青蛙、鱼，还有鸟。
Without them, plants would lose a pollinator.
没有了蚊子，植物会少掉一个授粉者。
But some scientists say that mosquitos aren't actually all that important.
不过也有些科学家称，蚊子其实没有那么重要。
If we got rid of them, they argue,
他们说，如果我们消灭了蚊子，
another species would simply take their place and we'd probably have far fewer deaths from malaria.
其他一些物种可以轻易地取代它们的位置，而疟疾导致死亡的人数会大幅下降。
The problem is that nobody knows what would happen if we killed off all the mosquitos.
但问题是，没有人知道灭绝蚊子后会发生什么。
Something better might take their spot or perhaps something even worse.
也许更好的物种会取代它们的位置，但也可能是更糟糕的物种。
The question is, are we willing to take that risk?
问题是，我们愿意冒这个险吗？