davidgagne.net

Women only stay with men for security, and men only stay with women for sex. It’s a cynical view of human relationships, but researchers now say it is the driving force behind the evolution of monogamy — and women started it. By offering sex all the time, females in monogamous species disguise whether they are fertile and trick males into sticking around.

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“The male has no cue,” says Enquist. “All he can see is the behaviour of the female.”
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