"the survival of the fittest," a slogan that virtually preempted all debate.

“适者生存”，一个几乎无可辩驳的口号。

《柯林斯英汉双解大词典》

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Natural selection ensures only the fittest survive to pass their genes on to the next generation.

物竞天择确保只有最适应环境的物种才得以生存下来，把基因传递给下一代。

《柯林斯英汉双解大词典》

The British philosopher Herbert Spencer described this struggle as "survival of the fittest."

VOA: special.2009.02.25

If evolution is survival of the fittest, nature red in tooth and claw, how could animals evolve moral feelings?

如果进化论是讲适者生存，在弱肉强食的自然界，动物怎么能进化出道德情感？

耶鲁公开课 - 心理学导论课程节选

During three frantic months late in 1975, Houghton changed Corning's management style from paternalistic to survival-of-the-fittest.

FORBES: The Trials Of Amory Houghton Jr.

This says that the "fittest" animals or plants are more likely to survive and reproduce.

BBC: Alfred Russel Wallace's 19th Century letters go online

Survival of the fittest means survival of those best able to adapt to changing circumstances.

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