In the early 1900s scientists found that animals have circadian rhythms, too: they also are capable of maintaining a 24-hour-long activity pattern in the absence of external cues such as light.

在20世纪初，科学家们发现，动物也有昼夜节律：即使没有如光线之类的外部变化的提示，动物也能保持一个24小时的活动周期。

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More worrying still is that the genes which confer this resistance are also showing up in bacteria found in other animals.

但大家该担忧的不只如此，因为某些动物身上的细菌也发现了抗药性基因。

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But these aspects of human behavior, or "culture", can also be found in lives of certain animals.

但是，人类的这些行为，也就是“文化”，也能在某些动物的生活中发现。

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They also found these highly social animals living in small, prison-like cages where some have languished for decades.

VOA: standard.2010.02.16

They also found that in the older animals glucose supply did not return to normal until 30 minutes after the task was completed.

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There is no hard evidence that the same kinds of pheromones found in animals also exist in humans, said Charles Wysocki, researcher at the Monell Chemical Senses Center in Philadelphia, Pennsylvania, and adjunct professor at the University of Pennsylvania.

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They also found changes in the mix of cells within the animals' immune system itself.

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