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？

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It is as though we are determined to regress to the most primitive condition of existence in the animal world, of the survival of the fittest.

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In past ages, the law governing the survival of the fittest roughly weeded out the less desirable strains.

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For one thing, the phenomenon of resistance to herbicides, antibiotics, pesticides and chemotherapeutic drugs is well-known and a largely unavoidable concomitant of evolutionary pressure, the result of survival of the fittest.

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