D. persimilis courtship shows some flexibility and courting males sometimes perform an elaborate postural display in addition to the standard courtship behaviours shared by most Drosophila species. This postural display includes the acrobatic contortion and tremulation of their abdomen, accompanied by the generation of substrate-borne vibrations, and they proffer a nutritional droplet to the female. Here, we use courtship and choice assays to ask what triggers this display and what advantages males may gain from it during courtship. In pair assays, we found no differences in the courtship duration and copulation success between displaying and non-displaying males. In trio assays, however, the female always mated with the male who performed the display. To investigate what promotes the male display, we varied the level of receptivity of the female and studied the impact of a second male. We found that rejection by the female does not induce the male to display, contrary to what was previously suggested. We present evidence that the male display is in fact promoted by the presence of an attentive and sexually receptive female and the absence of male competition, with the greatest exhibition rate obtained if the courted female is starved. These findings provide valuable information about the social ecology of flies, and how internal and external cues influence sexual behaviours and mate choice.

中文翻译：

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果蝇求偶姿势显示的触发因素

D. persimilis 求偶表现出一定的灵活性，除了大多数果蝇物种共有的标准求偶行为外，求偶的雄性有时还会表现出精心的姿势展示。这种姿势展示包括腹部的杂技扭曲和颤抖，伴随着基板振动的产生，它们为雌性提供营养液滴。在这里，我们使用求偶和选择分析来询问是什么触发了这种展示以及雄性在求偶过程中可能从中获得哪些优势。在配对分析中，我们发现展示和非展示雄性之间的求偶持续时间和交配成功率没有差异。然而，在三重分析中，雌性总是与进行展示的雄性交配。为了调查是什么促进了男性的表现，我们改变了雌性的接受程度，并研究了第二个雄性的影响。我们发现雌性的拒绝并不会促使雄性表现出来，这与之前的建议相反。我们提供的证据表明，男性展示实际上是由细心和性接受的女性的存在以及男性竞争的缺席促进的，如果被追求的女性饥饿，则获得的展示率最高。这些发现提供了有关果蝇社会生态学以及内部和外部线索如何影响性行为和配偶选择的宝贵信息。我们提供的证据表明，男性展示实际上是由细心和性接受的女性的存在以及男性竞争的缺席促进的，如果被追求的女性饥饿，则获得的展示率最高。这些发现提供了有关果蝇社会生态学以及内部和外部线索如何影响性行为和配偶选择的宝贵信息。我们提供的证据表明，男性展示实际上是由细心和性接受的女性的存在以及男性竞争的缺席促进的，如果被追求的女性饥饿，则获得的展示率最高。这些发现提供了有关果蝇社会生态学以及内部和外部线索如何影响性行为和配偶选择的宝贵信息。