Multimodal signalling in the courtship of male parasitoid wasps: testing the multiple messages hypothesis

动物通过视觉、化学、听觉、振动甚至电子信号相互交流。然而，动物在发送重要信号时并不局限于一种信号模态，而是经常将联合收割机不同模态组合成一种多模态信号。但是，为什么动物要把使用两种模式的成本投入到一个信号中呢？一个假设是，模态传达不同的信息（多消息假设）。例如，它是可能的，一个模态传达物种身份，而其他模态传达信号的质量（物种识别假设）的信息。求偶行为在动物王国中很普遍，通常会强烈影响信号者的交配成功率。因此，这并不奇怪，求爱往往是复杂的，利用不仅一个，但几个模式。然而，即使求爱显示已被深入研究，在过去的几年里，多模式求偶信号的演变中的多个消息的作用仍然不清楚。在这里，我们建议使用寄生蜂属Leptopilina作为一个模型系统来研究多模态求爱信号，并测试是否不同的信号成分包含不同的信息。雄性的Leptopilina显示一个复杂的求爱显示由两个元素组成：翅膀扇和触角抚摸。我们的目的是测试的假设，这两个信号形式的男性求爱（翅膀扇=振动和触角抚摸大概转移一个男性触角信息素=化学）对应的物种识别假设的化学形式信号的物种身份和振动形式信号的质量的男性。在第一个实验中，我们将测试的能力之间的相关性，男性引起交配的女性和属性的翅膀扇，以及男性的化学配置文件的组成。在第二步中，我们将操纵在第一个实验中确定的特征，例如，通过减慢翅膀扇动的频率或通过修改化学特征，并测量对雄性交配成功的影响。在第三部分中，我们将测量求偶过程中使用的两种方式的物种特异性。为此，我们将比较翅扇的特点和化学配置文件的三种Leptopilina和外群。此外，将测试的假设，黄蜂的化学档案反映了个人的相关性，并用于避免近亲繁殖。在项目的第四部分，我们想测试，被雌性选择的雄性是否比被拒绝的雄性质量更高，或者这种配对是否会产生更有活力的后代。我们计划通过分析交配过程中转移的精子数量来衡量雄性的质量，并通过后代克服宿主免疫系统的能力来衡量后代的质量。

Animals communicate with each other using visual, chemical, acoustical, vibratory and even electrical signals. However, animals are not restricted to one signal modality when sending important signals, but frequently combine different modalities into one multimodal signal. But why should animals invest the costs of using two modalities in one signal? One hypothesis is that the modalities convey different information (multiple messages hypothesis). For example, it is possible that one modality conveys species identity while the other modality conveys information on the signaler’s quality (species recognition hypothesis). Courtships are widespread in the animal kingdom and usually strongly affect the mating success of the signaler. Consequently, it is not surprising that courtships are often complex, utilizing not only one but several modalities. However, even though courtship displays have been intensively studied over the last years, the role of multiple messages in the evolution of multimodal courtship signals is still unclear. Here we propose to use parasitoid wasps of the genus Leptopilina as a model system to study multimodal courtship signals and to test whether the different signaling components contain different pieces of information. Males of Leptopilina show a complex courtship display consisting of two elements: wing fanning and antennal stroking. Our aim is to test the hypothesis that the two signal modalities of the male courtship (wing fanning = vibratory and antennal stroking presumably transfers a male antennal pheromone = chemical) correspond to the species recognition hypothesis with the chemical modality signaling the species identity and the vibratory modality signaling the quality of the male. In a first experiment, we will test for a correlation between the ability of males to elicit matings in females and the properties of the wing fanning as well as the composition of the males’ chemical profile. In a second step we will manipulate the characteristics identified in the first experiment by, for example, slowing down the frequency of the wing fanning or by modifying the chemical profile and measure the effect on the male’s mating success. In the third part we will measure the species specificity of both modalities used during courtship. To this end, we will compare the wing fanning characteristics and the chemical profile of three species of Leptopilina and an outgroup. Furthermore, will test the hypothesis that the chemical profile of the wasps reflects the relatedness of individuals and is used to avoid inbreeding. In part four of the project, we want to test, whether the males chosen by the females are of higher quality than rejected males or whether such pairings result in more viable offspring. We are planning to measure the male’s quality by analyzing the number of sperms transferred during mating and offspring quality by the ability of the offspring to overcome the immune system of the host.