Sex pheromones in Neotropical tree frogs (Hylidae) - Insights into an under-studied communication mode in anurans

化学通讯是动物界中进化最古老的通讯系统，对许多物种的性行为尤为重要。与其他动物相比，关于无尾两栖类的信息素的研究是非常罕见的，尽管许多无尾两栖类物种具有繁殖腺，其中建议含有性信息素。在五个新热带区树蛙物种的例子中，在身体的不同区域表现出雄性繁殖腺，我想研究性信息素在这个世界上最大的青蛙家族（雨蛙科）中的使用。为了这个目的，我计划1）在墨西哥和秘鲁的原生栖息地对这些青蛙进行采样，2）组织学检查它们的繁殖腺，并将它们可视化在3D模型中，3）使用遗传学和化学方法（下一代测序和HPLC）分离和鉴定信息素腺内容物，4）在该领域的行为测定中测试求爱期间性信息素的意义。通过这项研究，我计划扩大到目前为止非常有限的知识的使用和结构的求偶信息素在无尾两栖类。对同一科不同种属之间的信息素进行比较，以及与迄今为止鉴定的其他两栖动物物种（尤其是蝾螈）的化学化合物进行比较，可能会进一步了解两栖动物求爱信息素的进化，特别是无尾两栖动物。

Chemical communication is the evolutionary oldest communication system in the animal kingdom and it is especially important for the sexual behaviour in many species. Compared to other animals, studies regarding pheromones in anurans are extremely scarce, although many anuran species possess breeding glands which are suggested to contain sex pheromones. On the example of five Neotropical tree frog species that exhibit male breeding glands in different regions of the body, I want to investigate the use of sex pheromones in this worldwide biggest frog family (Hylidae). For this purpose I plan to 1) sample these frogs in their native habitats in Mexico and Peru, 2) histologically examine their breeding glands and visualize them in 3D-models, 3) isolate and identify the pheromonal gland contents using genetical and chemical methods (next generation sequencing and HPLC) and 4) test the significance of the sex pheromones during courtship in behavioural assays in the field. With this study I plan to expand the so far very restricted knowledge of the usage and structure of courtship pheromones in anurans. A comparison of the pheromones between the different species and genera within the same family as well as with so far identified chemical compounds of other amphibian species (especially salamanders) might lead to a further understanding of the evolution of courtship pheromones in amphibians generally and in anurans in particular.