Закон Шмальгаузена

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That result, which we shall call "Schmalhausen's Law," is that when organisms are living within their normal range of environment, perturbations in the conditions of life and most genetic differences between individuals have little or no effect on their manifest physiology and development, but that under severe or unusual general stress conditions [where selection has not had the opportunity to operate] even small environmental and genetic differences have major effects.

Richard Lewontin & Richard Levins (2000) Schmalhausen's law, Capitalism Nature Socialism, 11:4, 103-108, DOI: 10.1080/10455750009358943

http://www.tandfonline.com/doi/abs/10.1080/10455750009358943

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