时差N小时 鸟能识别人类吗?

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

鸟类究竟是愚蠢还是聪明呢？称某人为“鸟脑”通常意味着侮辱。但很多鸟儿其实非常聪明。例如知更鸟。对于你、我来说，所有的知更鸟可能看起来都一样。但是从鸟的角度来看，这一理论却不适用于人类。

Mockingbirds can tell one person from another with great skill, especially when that person poses¹ a threat. In one experiment, scientists had volunteers approached and touched mockingbird nests once a day for four days. By the second day, the birds began their warning calls and attack runs sooner than they had the day before. By the fourth day, the birds appeared 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，知更鸟技巧高超，特别是有人威胁它时。在一项试验中，科学家们让志愿者们去接近、触碰知更鸟的窝巢，每天一次，连续四天。第二天，鸟儿们便鸣叫警告、突袭来者，反应比前一天更迅速。到第四天，一旦志愿者们开始接近鸟巢，知更鸟便能辨别出那位人类入侵者。

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

然而到了第五天，换一位陌生面孔的志愿者去接近、触摸鸟巢。知更鸟的反应又慢下来。因此换句话说，鸟类对入侵者也会区别对待，并不会一味地气势汹汹。

They quickly recognized repeat intruders and were quick to target them. Because the new intruder wasn't familiar, the birds took longer to size him up. Mockingbirds might not be the only bird species² to distinguish³ between people. Other species that have adapted to human environments might be good people spotters, too. In fact, this ability might be part of what allows some birds to thrive in urban environments.

他们很快地识别重复入侵者，并快速攻击他们。因为对新的入侵者并不熟悉，所以知更鸟要花更长时间来做出判断。知更鸟可能并不是唯一能够区别人类的鸟类。其它一些已经适应了人类环境的鸟类，可能也十分善于识别人类。事实上这种能力会帮助鸟类在现代环境中生存下去。

1 poses   

使摆姿势( pose的第三人称单数 )； 以…身份出现； 招摇； 炫耀

参考例句：

• This poses a threat to agriculture and the food chain, and consequently to human health. 这会对农业和食物链造成威胁，由此而危及人的健康。
• The high cost of oil poses serious problems for industry. 昂贵的石油价格给工业造成了严重困难。

2 species   

n.物种，种群

参考例句：

• Are we the only thinking species in the whole of creation?我们是万物中惟一有思想的物种吗？
• This species of bird now exists only in Africa.这种鸟现在只存在于非洲。

3 distinguish   

vt.区别，辩明，识别，辨认出；vi.区别，辨别，识别

参考例句：

• It is not easy to distinguish cultured pearls from genuine pearls.辨别真正的珍珠与养殖的珍珠不容易。
• Some people find it difficult to distinguish right from wrong.一些人认为很难辨对与错。