Alonso-pimentel H, Papaj DR
Department of Ecology and Evolutionary Biology, University of Arizona
Anim Behav. 1999 May;57(5):1063-1069. doi: 10.1006/anbe.1998.1079.
The effects of the interaction between the operational sex ratio (OSR) and a resource (i.e. oviposition site) on mating dynamics have rarely been considered. We examined the effect of the resource presence and its interaction, with the effect of OSR on copulation duration in Rhagoletis juglandis, a tephritid fly species characterized by a resource-defence mating system in which males defend territories on walnut fruit. In this species, copulation duration varies from 30 s to over 1 h and was shown previously to respond strongly to changes in OSR. In the field, short copulations tended to begin and end on fruit, whereas most long copulations generally began on fruit but ended in the foliage, suggesting a possible effect of resource presence on the copulation duration. In laboratory assays of isolated pairs, copulations were significantly shorter in the presence of a surrogate fruit, confirming the effect of resource presence. In another laboratory assay, in which we manipulated OSR independently of resource presence, resource presence and OSR were additive in their effects. Results are discussed in the context of sperm competition theory. Copyright 1999 The Association for the Study of Animal Behaviour.
操作性别比（OSR）与一种资源（即产卵场所）之间的相互作用对交配动态的影响很少被考虑。我们研究了资源的存在及其相互作用对胡桃实蝇交配持续时间的影响，胡桃实蝇是一种实蝇科昆虫，其交配系统以资源防御为特征，即雄性在胡桃果实上保卫领地。在这个物种中，交配持续时间从30秒到超过1小时不等，并且先前已证明其对OSR的变化有强烈反应。在野外，短时间交配倾向于在果实上开始和结束，而大多数长时间交配通常在果实上开始但在树叶中结束，这表明资源的存在可能对交配持续时间有影响。在隔离配对的实验室试验中，在有替代果实的情况下交配明显更短，证实了资源存在的影响。在另一项实验室试验中，我们独立于资源存在来操纵OSR，结果表明资源存在和OSR的影响是相加的。本文在精子竞争理论的背景下对结果进行了讨论。版权所有1999年动物行为研究协会。
