Natural Selection: Sex Ratio
نویسنده
چکیده
Natural selection acts strongly on the proportional numbers of male and female offspring among the progeny of adults. The equilibrium is often one at which males and females are produced in roughly equal numbers, but under certain ecological and genetic circumstances there may be dramatic population-wide biases, and even in populations with balanced sex ratios, parents are often selected to produce strongly maleor femalebiased progenies in response to variations in their individual condition.
منابع مشابه
Sexual selection favors female-biased sex ratios: the balance between the opposing forces of sex-ratio selection and sexual selection.
In a verbal model, Trivers and Willard proposed that, whenever there is sexual selection among males, natural selection should favor mothers that produce sons when in good condition but daughters when in poor condition. The predictions of this model have been the subject of recent debate. We present an explicit population genetic model for the evolution of a maternal-effect gene that biases off...
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