Mathematical toy model inspired by the problem of the adaptive origins of the sexual orientation continuum

Brian Skinner

doi:10.1098/rsos.160403

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arXiv · 1511.03721

Mathematical toy model inspired by the problem of the adaptive origins of the sexual orientation continuum

Brian Skinner

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Abstract

Same-sex sexual behavior is ubiquitous in the animal kingdom, but its adaptive origins remain a prominent puzzle. Here I suggest the possibility that same-sex sexual behavior arises as a consequence of the competition between an evolutionary drive for a wide diversity in traits, which improves the adaptability of a species, and a drive for sexual dichotomization of traits, which promotes opposite-sex attraction and increases the rate of reproduction. A simple analytical "toy model" is proposed for describing this tradeoff. The model exhibits a number of interesting features, and suggests a simple mathematical form for describing the sexual orientation continuum.

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Brian Skinner. 2016-09-15. Mathematical toy model inspired by the problem of the adaptive origins of the sexual orientation continuum. https://doi.org/10.1098/rsos.160403

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