Nilsson Tina, Fricke Claudia, Arnqvist Goran
Department of Ecology and Environmental Science, Umeå University, Sweden.
Evolution. 2002 Jan;56(1):111-20. doi: 10.1111/j.0014-3820.2002.tb00853.x.
Sexual selection can lead to rapid divergence in reproductive characters. Recent studies have indicated that postmating events, such as sperm precedence, may play a key role in speciation. Here, we stress that other components of postmating sexual selection may be involved in the evolution of reproductive isolation. One of these is the reproductive investment made by females after mating (i.e., differential allocation). We performed an experiment designed to assess genetic divergence in the effects of mating on female reproductive performance in flour beetles, Tribolium castaneum. Females were mated to males of three different wild-type genotypes at two different frequencies, in all possible reciprocal combinations. Male genotype affected all aspects of female reproduction, through its effects on female longevity, total offspring production, reproductive rate, mating rate, and fertility. Moreover, male and female genotype interacted in their effects on offspring production and reproductive rate. We use the pattern of these interactions to discuss the evolutionary process of divergence and suggest that the pattern is most consistent with that expected if divergence was driven by sexually antagonistic coevolution. In particular, the fact that females exhibited a relatively weak response to males with which they were coevolved suggests that females have evolved resistance to male gonadotropic signals/stimuli.
性选择可导致生殖特征的快速分化。近期研究表明，交配后的事件，如精子优先性，可能在物种形成中起关键作用。在此，我们强调交配后性选择的其他成分可能参与了生殖隔离的进化。其中之一是雌性在交配后进行的生殖投资（即差异分配）。我们进行了一项实验，旨在评估交配对赤拟谷盗（Tribolium castaneum）雌性生殖性能影响的遗传分化。雌性以两种不同频率与三种不同野生型基因型的雄性交配，所有组合均为正反交。雄性基因型通过对雌性寿命、总后代产量、生殖率、交配率和生育力的影响，影响雌性生殖的各个方面。此外, 雄性和雌性基因型在对后代产量和生殖率的影响上存在相互作用。我们利用这些相互作用的模式来讨论分化的进化过程，并表明该模式与性对抗性协同进化驱动分化时预期的模式最为一致。特别是，雌性对与其共同进化的雄性表现出相对较弱的反应这一事实表明，雌性已经进化出对雄性促性腺信号/刺激的抗性。
