Olfactory mate choice in the Greater sac-winged bat (Saccopteryx bilineata): Influence of immunocompetence and parasites

许多动物物种使用嗅觉信号来获得关于同种的信息，例如个体身份，生殖状态，相关性和适应性。最重要的适应性参数之一是个体对抗寄生虫和病原体的能力。因此，获得有关同种的免疫活性和当前感染状态的信息可以帮助降低疾病感染的风险，因此被认为是配偶选择的重要因素。虽然对嗅觉和配偶选择的研究主要集中在实验室哺乳动物身上，但缺乏证据表明气味在野生动物物种的免疫能力和感染状况中的作用。具体来说，目前还不清楚雌性是否会利用这些信息来选择配偶。该项目旨在通过调查气味在信号免疫能力和感染状态中的作用及其对蝙蝠野生种群择偶决定的影响来缩小这一知识差距，这些蝙蝠暴露于自然病原体，从而在自然条件下发挥作用。调查将在更大的囊翅蝙蝠，Saccotperyx bilineata，蝙蝠物种的气味是一个重要组成部分的求偶显示。以前的研究表明，雄性大囊翅蝠的翅囊气味包含有关个体身份、生殖状况、地理距离和物种的信息，但迄今为止尚不清楚雌性蝙蝠的当前感染状况和免疫能力。我们的目的是在测试这一假设收集相关的实验数据，从动物的两个野生种群在哥斯达黎加。通过结合实验和相关研究，本项目旨在为我们理解嗅觉线索在哺乳动物择偶决策中的作用提供重要贡献。

Many animal species use olfactory signals to gain information about conspecifics, such as individual identity, reproductive status, relatedness and fitness. One of the most important fitness parameter is an individual’s ability to fight parasites and pathogens. Thus, gaining information about the immunocompetence and the current infection status of a conspecific can help to decrease the risk of disease contraction and is therefore assumed to be an important factor in mate choice. While studies on olfaction and mate choice have mainly concentrated on laboratory mammals, there is a lack of evidence on the role of odour in signalling immunocompetence and infection status in wildlife species. Specifically, it is unclear if females use such information to choose a mate. This project aims to close this knowledge gap by investigating the role of odour in signalling immunocompetence and infection status, and its influence on mate choice decisions in wild populations of bats, which are exposed to natural pathogens, thus acting under natural conditions. Investigations will be done on the greater sac-winged bat, Saccotperyx bilineata, a bat species where odour is an important component of the courtship display. Former studies have shown that the wing sac odour of male greater sac-winged bats contains information about individual identity, reproductive status, geographic distance and species, but is so far unknown to inform females about the current infection status and immunocompetence. We aim at testing this hypothesis by collecting correlative and experimental data from animals of two wild populations in Costa Rica. By combining experimental and correlative studies, this project thus aims at providing an important contribution to our understanding about the role of olfactory cues in mate choice decisions in mammals.