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Evolutionary biology

Why reproduction often takes two

On the face of it, self-fertilization is the efficient way to breed: compared with outcrossing, there's usually much less fuss, for a start. So why isn't reproduction by selfing far more prevalent than it is?

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Figure 1: Fit for evolutionary studies — the nematode Caenorhabditis elegans.



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Agrawal, A. Why reproduction often takes two. Nature 462, 294–295 (2009).

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