This fear mechanism is critical to the survival of all animals, but no one can say for sure whether beasts other than humans know they're afraid.

这种恐惧机制对所有动物的生存都至关重要，但没有人能肯定人类以外的动物是否知道自己在恐惧。

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Indeed, the outgoing affability of most dogs towards humans and other dogs is in sharp contrast to the mix of fear and aggression with which wolves react to animals from other packs.

事实上，狗在对待人类和其他同类的狗时表现出的温善和蔼与狼对待其他群属里的动物时表现出的谨慎敌视形成了鲜明的对比。

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Increased stresses included a fear of the wild: unproductive wild lands; wild animals; and vermin.

我们越来越大的压力来自于对未开发世界的恐惧：包括未开发的土地；野生动物，和寄生虫。

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Some evolutionary psychologists believe that the latter is rooted in the universal fear of animals and an associated attempt to appease the beasts through emulation.

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The next day the animals' fear of the tone had greatly diminished, indicating that the drug had prevented the old memory from being stored again.

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The animals have no fear of humans, so your children will swim with dolphins and turtles and play near seals.

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