Evolution of morphology and ecology in hyperdiverse larval amphibian communities in Madagascar

热带地区的无尾两栖类(蛙)群落经常达到惊人的物种多样性水平，在一个地点出现多达50-100个物种。很少有研究系统地探讨导致这些大量物种共存的因素。考虑到成体阶段的相关物种在形态或营养上并不倾向于占据完全不同的生态位，幼体阶段的生态位分配可能是形成这些物种丰富的群落的关键因素。本项目试图通过结合一些创新技术和使用高度适合的模型区，对高度多样化的热带蝌蚪群落进行首次大规模生态学研究。这项研究将在马达加斯加进行，那里的无尾两栖动物分类学已经基本确定，申请者和其他同事已经收集了关于这些生物的大型分子、系统发育、分布和生物声学数据库。蝌蚪将通过DNA条形码被识别为物种，这是证明这项技术适用于使用分子方法大规模识别脊椎动物生活史阶段的首批现场研究之一。将对各种自体和妇科参数进行筛选。营养水平将使用稳定同位素进行比较评估，这是一项成熟的技术，但到目前为止还没有应用于两栖幼虫。获得的生态地貌特征将沿着马达加斯加蛙现有的、完整的和分辨率良好的分子系统学绘制，并使用贝叶斯和似然统计来追踪它们的进化。

Anuran (frog) communities in the tropics often reach remarkable levels of species diversity, with up to 50-100 species occurring at one site. Few studies have systematically addressed the factors allowing these high numbers of species to co-exist. Considering that related species of frogs in their adult phase do not tend to occupy radically different niches in morphology or nutrition, niche partitioning in the larval phase may be a key factor shaping these species-rich communities. The present project attempts the first large-scale ecological study of a hyperdiverse tropical tadpole community, by combining a number of innovative techniques and using a highly suitable model region. The study will be carried out in Madagascar, where anuran systematics are largely settled and large molecular, phylogenetic, distributional and bioacoustic databases on these organisms have been assembled by the applicant and other colleagues. Tadpoles will be identified to species by DNA barcoding, representing one of the first field studies to demonstrate the applicability of this technique to identify vertebrate life-history stages at a large scale using molecular methods. A variety of autecological and synecological parameters will be screened. Trophic levels will be comparatively assessed using stable isotopes, a well-established technique which, however, has so far not been applied to larval amphibians. The obtained ecomorphological characters will be plotted along an existing, complete and well-resolved molecular phylogeny of Madagascan frogs, and their evolution traced using Bayesian and likelihood statistics.