当画眉鸟夫人离开巢穴去捉虫子回来喂养她的孩子们的时候，就有四张小画眉鸟的嘴巴和一张巨大布谷鸟的嘴巴大张着。

When Mrs. Thrush leaves the nest to get a worm and comes back to feed her young, there are four little thrush mouths and one huge cuckoo mouth.

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研究人员把16只鸟按顺序4只排成一排，发现外面的鸟在32%的时间里处于半睡眠状态，而内部的鸟只有12%的时间处于半睡眠状态。

Rotating 16 birds through the positions in a four-duck row, the researchers found outer birds half-asleep during some 32 percent of dozing time versus about 12 percent for birds in internal spots.

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不论群里有多少鸟，每只鸟的飞行的方向和速度，同其他鸟的方向和速度都是不变化的。

Regardless of size, the correlations of a bird’s orientation and velocity with the other birds’ orientation and velocity didn’t vary.

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