Researchers find that eyes of blind cavefish are not lost by disuse, but blindness evolves because fish with eyes may be attracted to light and preferentially leave caves. Even a low level of emigration, e.g. 2%, would provide significant local adaptation and the evolution of blindness in caves.

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Researchers find that eyes of blind cavefish are not lost by disuse, but blindness evolves because fish with eyes may be attracted to light and preferentially leave caves. Even a low level of emigration, e.g. 2%, would provide significant local adaptation and the evolution of blindness in caves.