Natural selection and the advantage of recombination

Gerrish, P. J.; Galeota-Sprung, B.; Cordero, F.; Sniegowski, P. D.; Colato, A.; Hengartner, N. W.; Vejalla, V.; Chevalier, J.; Ycart, B.

doi:10.1101/2020.08.28.271486

bioRxiv · 10.1101/2020.08.28.271486

Natural selection and the advantage of recombination

Gerrish, P. J.·Galeota-Sprung, B.·Cordero, F.·Sniegowski, P. D.·Colato, A.·Hengartner, N. W.·Vejalla, V.·Chevalier, J.·Ycart, B.

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Abstract

The ubiquity of sex and recombination in nature is widely viewed as enigmatic, despite an abundance of limited-scope explanations. Natural selection, it seems, should amplify well-matched combinations of genes. Recombination would break up these well-matched combinations and should thus be suppressed. We show, to the contrary, that on average: 1) natural selection amplifies poorly-matched gene combinations and 2) creates time-averaged negative associations in the process. Recombination breaks up these poorly-matched combinations, neutralizes the negative associations, and should thus be passively and universally favored.

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Gerrish, P. J., Galeota-Sprung, B., Cordero, F., Sniegowski, P. D., Colato, A., Hengartner, N. W., Vejalla, V., Chevalier, J., Ycart, B.. 2020-08-30. Natural selection and the advantage of recombination. https://doi.org/10.1101/2020.08.28.271486

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