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Biological Fact and Theory


IT seems to me that all the facts of genetics must be accepted so far as they are supported by evidence, but the antagonism of some biologists is, I think, chiefly due to the complacency with which geneticists assume and assert that their discoveries explain all the important phenomena of biology, including the evolution of adaptations. Prof. T. H. Morgan believes that change of structure has been due to mutation, and that organisms have adapted their habits accordingly. I know of no case of mutation which is in any way parallel to the metamorphosis of the flat-fish or the frog.

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CUNNINGHAM, J. Biological Fact and Theory. Nature 119, 563 (1927).

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