Males Have Adapted To Battle With Competing Sperm

"In the context of sexual reproduction, natural selection is generally thought of as a pre-copulation mechanism. We are drawn to features of the human body that tell us our partner is healthy and will provide us a fighting opportunity to carry on our genetic lineage... a[n]... article [in] Psychological Science suggests that the human male has evolved mechanisms to pass on his genes during post-copulation as well, a phenomenon dubbed 'sperm competition.'"

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