雌性垄断介导了交配前和交配后性特征之间的关系。

Female monopolization mediates the relationship between pre- and postcopulatory sexual traits.

机构信息

Department of Biology, Life Sciences Complex, 107 College Place, Syracuse University, Syracuse, New York 13244-1270, USA.

Centre for Evolutionary Biology, School of Animal Biology (M092), University of Western Australia, Crawley, Western Australia 6009, Australia.

出版信息

Nat Commun. 2014;5:3184. doi: 10.1038/ncomms4184.

DOI:10.1038/ncomms4184

PMID:24452310

Abstract

Theory predicts a trade-off between investments in precopulatory (ornaments and armaments) and postcopulatory (testes and ejaculates) sexual traits due to the costs associated with their growth and maintenance within the finite energy resources available. Empirical studies, however, have revealed considerable inconsistency in the strength and direction of relationships among these sexual traits. Ambiguity may result from variance in the marginal benefits gained by increasing investments in either pre- or postcopulatory sexual traits. Here, in a broad comparative study, we test the prediction that the relationship between pre- and postcopulatory sexual traits differs among taxa relative to the importance of male-male contest competition within them. We find that covariance between pre- and postcopulatory sexual traits gradually shifts from strongly positive to strongly negative with increasing male-male contest competition. Thus, our findings reveal a potentially unifying explanation for the oftentimes inconsistent relationships in the strength and direction of covariance among sexual traits.

摘要

理论预测，由于与有限的可用能源资源相关的生长和维持成本，在交配前（装饰和武器）和交配后（睾丸和精液）的性特征之间存在权衡取舍。然而，实证研究表明，这些性特征之间的关系的强度和方向存在相当大的不一致。这种模糊性可能是由于增加对交配前或交配后性特征的投资所获得的边际收益的差异造成的。在这里，我们进行了一项广泛的比较研究，检验了这样一个预测，即在相对于雄性间竞争竞争的重要性的情况下，交配前和交配后性特征之间的关系在不同分类群之间存在差异。我们发现，随着雄性间竞争的增加，交配前和交配后性特征之间的协方差逐渐从强正变为强负。因此，我们的研究结果为性特征之间的协方差强度和方向的不一致关系提供了一个潜在的统一解释。