Centre d'Écologie Fonctionnelle et Évolutive, UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, École Pratique des Hautes Études, 1919 Route de Mende, 34293 Montpellier Cedex 05, France.
Animal Evolutionary Ecology Group, Institute for Evolution and Ecology, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
Sci Adv. 2016 Feb 12;2(2):e1500983. doi: 10.1126/sciadv.1500983. eCollection 2016 Feb.
Since Darwin's conception of sexual selection theory, scientists have struggled to identify the evolutionary forces underlying the pervasive differences between male and female behavior, morphology, and physiology. The Darwin-Bateman paradigm predicts that anisogamy imposes stronger sexual selection on males, which, in turn, drives the evolution of conventional sex roles in terms of female-biased parental care and male-biased sexual dimorphism. Although this paradigm forms the cornerstone of modern sexual selection theory, it still remains untested across the animal tree of life. This lack of evidence has promoted the rise of alternative hypotheses arguing that sex differences are entirely driven by environmental factors or chance. We demonstrate that, across the animal kingdom, sexual selection, as captured by standard Bateman metrics, is indeed stronger in males than in females and that it is evolutionarily tied to sex biases in parental care and sexual dimorphism. Our findings provide the first comprehensive evidence that Darwin's concept of conventional sex roles is accurate and refute recent criticism of sexual selection theory.
自达尔文提出性选择理论以来，科学家们一直在努力确定导致雄性和雌性行为、形态和生理学之间普遍存在差异的进化力量。达尔文-贝特曼范式预测，雌雄配子大小差异会对雄性施加更强的性选择，进而在雌性偏爱的亲代养育和雄性偏爱的性二型性方面推动传统性别角色的进化。尽管这一范式构成了现代性选择理论的基石，但它在动物生命树中仍然未经检验。这种缺乏证据的情况促使了替代假说的兴起，这些假说认为性别差异完全是由环境因素或偶然因素驱动的。我们证明，在整个动物界中，标准的贝特曼指标所捕捉到的性选择确实在雄性中比在雌性中更强，并且它与亲代养育和性二型性方面的性别偏见在进化上是相关的。我们的研究结果提供了第一个全面的证据，证明达尔文关于传统性别角色的概念是准确的，并反驳了对性选择理论的最新批评。
