時差N小時:鳥能識別人類嗎?

How dumb, or smart, are birds? Calling someone abirdbrain is usually meant as an insult. But manybirds are quite clever. Take, for example, themockingbird. To you and me, one mockingbird mightlook pretty much like any other. But from the birds'perspective, the same isn't true of humans.

鳥類究竟是愚蠢還是聰明呢?稱某人為“鳥腦”通常意味著侮辱。但很多鳥兒其實非常聰明。例如知更鳥。對于你、我來說，所有的知更鳥可能看起來都一樣。但是從鳥的角度來看，這一理論卻不適用于人類。

Mockingbirds can tell one person from another with great skill, especially when that personposes a threat. In one experiment, scientists had volunteers approached and touchedmockingbird nests once a day for four days. By the second day, the birds began their warningcalls and attack runs sooner than they had the day before. By the fourth day, the birdsappeared to be able to spot the human intruders as soon as they began to approach the nests.

在分辨不同的人方面，知更鳥技巧高超，特別是有人威脅它時。在一項試驗中，科學(xué)家們讓志愿者們?nèi)ソ咏⒂|碰知更鳥的窩巢，每天一次，連續(xù)四天。第二天，鳥兒們便鳴叫警告、突襲來者，反應(yīng)比前一天更迅速。到第四天，一旦志愿者們開始接近鳥巢，知更鳥便能辨別出那位人類入侵者。

On the fifth day, however, a new person approached and touched the birds' nests. And thebirds were slower to react. So in other words, the birds weren't simply protecting their nestswith the same ferocity no matter who approached.

然而到了第五天，換一位陌生面孔的志愿者去接近、觸摸鳥巢。知更鳥的反應(yīng)又慢下來。因此換句話說，鳥類對入侵者也會區(qū)別對待，并不會一味地氣勢洶洶。

They quickly recognized repeat intruders and were quick to target them. Because the newintruder wasn't familiar, the birds took longer to size him up. Mockingbirds might not be theonly bird species to distinguish between people. Other species that have adapted to humanenvironments might be good people spotters, too. In fact, this ability might be part of whatallows some birds to thrive in urban environments.

他們很快地識別重復(fù)入侵者，并快速攻擊他們。因為對新的入侵者并不熟悉，所以知更鳥要花更長時間來做出判斷。知更鳥可能并不是唯一能夠區(qū)別人類的鳥類。其它一些已經(jīng)適應(yīng)了人類環(huán)境的鳥類，可能也十分善于識別人類。事實上這種能力會幫助鳥類在現(xiàn)代環(huán)境中生存下去。