School of Biological Sciences, Monash University, Victoria 3800, Australia.
BMC Evol Biol. 2011 Aug 9;11:233. doi: 10.1186/1471-2148-11-233.
Male sexual displays play an important role in sexual selection by affecting reproductive success. However, for such displays to be useful for female mate choice, courtship should vary more among than within individual males. In this regard, a potentially important source of within male variation is adjustment of male courtship effort in response to female traits. Accordingly, we set out to dissect sources of variation in male courtship effort in a fish, the desert goby (Chlamydogobius eremius). We did so by designing an experiment that allowed simultaneous estimation of within and between male variation in courtship, while also assessing the importance of the males and females as sources of courtship variation.
Although males adjusted their courtship depending on the identity of the female (a potentially important source of within-male variation), among-male differences were considerably greater. In addition, male courtship effort towards a pair of females was highly repeatable over a short time frame.
Despite the plasticity in male courtship effort, courtship displays had the potential to reliably convey information about the male to mate-searching females. Our experiment therefore underscores the importance of addressing the different sources contributing to variation in the expression of sexually-selected traits.
雄性的性展示在性选择中起着重要作用，因为它们会影响繁殖成功率。然而，为了让这些展示对雌性的择偶有用，求偶行为应该在个体之间的差异大于个体内部的差异。在这方面，雄性内部求偶努力变化的一个潜在重要来源是雄性根据雌性特征来调整求偶努力。因此，我们着手剖析一种鱼类——沙漠虾虎鱼（Chlamydogobius eremius）雄性求偶努力的变化来源。我们通过设计一个实验来实现这一目标，该实验允许同时估计雄性内部和雄性之间的求偶变化，同时评估雄性和雌性作为求偶变化来源的重要性。
尽管雄性会根据雌性的身份来调整求偶行为（这是雄性内部变化的一个潜在重要来源），但雄性之间的差异要大得多。此外，雄性在短时间内对一对雌性的求偶努力具有高度的可重复性。
尽管雄性的求偶努力具有可塑性，但求偶行为有可能向正在寻找配偶的雌性可靠地传递有关雄性的信息。因此，我们的实验强调了在表达受性选择影响的特征时，需要考虑不同的来源对变化的贡献。
