What's the worst bug on the planet? You might vote for the horsefly or perhaps the wasp, but for many people, the worst offender is by far the mosquito. The buzzing, the biting, the itching, the mosquito is one of the most commonly detested pests in the world. In Alaska, swarms of mosquitos can get so thick that they actually asphyxiate caribou. And mosquito-borne diseases kill millions of people every year. The scourge that is the mosquito isn't new. Mosquitoes have been around for over a hundred million years and over that time have coevolved with all sorts of species, including our own. There are actually thousands of species of mosquitos in the world, but they all share one insidious quality: they suck blood, and they're really, really good at sucking blood. Here's how they do it. After landing, a mosquito will slather some saliva onto the victim's skin, which works like an antiseptic, numbing the spot so we don't notice their attack. This is what causes the itchy, red bumps, by the way. Then the bug will use its serrated mandibles to carve a little hole in your skin, allowing it to probe around with its proboscis, searching for a blood vessel. When it hits one, the lucky parasite can suck two to three times its weight in blood. Turns out we don't really like that too much. In fact, humans hate mosquitos so much that we spend billions of dollars worldwide to keep them away from us -- from citronella candles to bug sprays to heavy-duty agricultural pesticides. But it's not just that mosquitos are annoying, they're also deadly. Mosquitos can transmit everything from malaria to yellow fever to West Nile virus to dengue. Over a million people worldwide die every year from mosquito-borne diseases, and that's just people. Horses, dogs, cats, they can all get diseases from mosquitoes too. So, if these bugs are so dastardly, why don't we just get rid of them? We are humans after all, and we're pretty good at getting rid of species. Well, it's not quite so simple. Getting rid of the mosquito removes a food source for lots of organisms, like frogs and fish and birds. Without them, plants would lose a pollinator. But some scientists say that mosquitos aren't actually all that important. If we got rid of them, they argue, another species would simply take their place and we'd probably have far fewer deaths from malaria. The problem is that nobody knows what would happen if we killed off all the mosquitos. Something better might take their spot or perhaps something even worse. The question is, are we willing to take that risk? (Buzzing)
世界上最可惡的蟲是什麼? 你可能投給馬蠅 又或許黃蜂 但大部分人都覺得 最惹人討厭的莫過於蚊子 它的嗡嗡聲 它會咬人 它帶來的搔癢 蚊子是這世界上 最令人厭惡的一種害蟲 在阿拉斯加州, 密密麻麻的蚊子 甚至可以令馴鹿窒息 還有蚊子傳播的疾病每年奪取 百萬人以上 蚊子的禍害不是新聞 蚊子已經在世上 超過一億年 和包括我們在內的 和其它生物 一起演化 在地球上 有上千種的蚊子 但它們都有一個 惹人討厭的共通點: 它們會吸血 它們真的非常善於吸血 看看它們如何做到的 蚊子著陸後會 塗抹一些唾液在受害者皮膚上 這就好像麻醉劑一樣 麻醉傷口讓 我們不會發現它們的襲擊 也因此傷口會變成紅癢的疙瘩 之後蚊子會用鋸齒狀的顎 在你的皮膚上戳出一個小洞 而可以讓它的吻管 鑽進皮膚 尋找血管 當它找到的時候 這個幸運的寄生蟲 可以吸取它的體重兩到三倍的血液 我們非常不喜歡被蚊子叮 事實上,人類痛恨蚊子 我們甚至花費數十億美元 使它們遠離我們 -- 由香茅蠟燭 到除蟲噴霧劑 甚至高強度的農業殺蟲劑 但是不只是 因為蚊子非常煩人 它們還可以令人致命 蚊子可以傳播各種疾病 由瘧疾 黃熱病 西尼羅河病毒 到登革熱 全球最少有 100 萬人 每年死於由蚊子傳播的疾病 而且這只是人類 馬、狗、貓 它們都可能染上蚊子傳播的疾病。 那麼,如果這些蚊子如此卑鄙 為什麼我們不把它們消滅呢? 畢竟我們是人類 我們很擅長令物種滅絕 事實並非如此單純 消滅蚊子 會消滅很多生物的 食物來源 例如:青蛙、魚、鳥 沒有蚊子, 植物會少一種授粉者 不過也有一些科學家說 其實蚊子沒有那麼重要 他們認為 如果我們消滅了蚊子 會有另一種物種 可以輕易地取代它們的位置 而瘧疾導致死亡的人數也會大幅下降 問題是 沒有人能夠知道會發生什麼事 如果我們滅絕所有蚊子 或許有更好的物種會取代它們的位置 或可能會更糟糕 問題在於 我們是否願意冒險?