Phylogenomic insights into a non-model adaptive radiation of freshwater snails from Sulawesi (Indonesia)

古老的湖泊，即存在超过10万年的湖泊，是淡水生物多样性的关键来源和特有物种的热点。它们的年龄相当大，使它们适合研究过去的殖民史，以及湖内多样化/物种形成动态及其内在和外部因素。该项目的最终目的是增进对苏拉威西特有淡水蜗牛辐射的基因组基础的了解，以及营养专门化在塑造生活在古马利利湖系统和波索湖的今天的动物群中所起的作用。在这里，通过全基因组测序得到的基因组数据将被生成所有Tylomelania物种，即河流和湖泊类群，以及其姊妹属Pusopotamis的代表。这些数据将被用来组装有丝分裂基因组，但更重要的是，识别SNPs，这些SNPs将被用来推断这个属的强大和古老的脊椎系统发育。派生的系统发育关系将有助于1)重建Tylomelania在整个岛屿和湖泊中的殖民历史，2)研究这些湖泊内以及河流和湖泊物种之间的杂交程度，以及3)评估形态空间(即贝壳和放射状形态)在栖息地转变过程中如何随时间变化。

Ancient lakes, i.e. lakes that existed for more than 100,000 years, are key sources of freshwater biodiversity and hotspots of endemism. Their considerably old age make them suitable to study past colonization histories and as well as intralacustrine diversification/speciation dynamics and their underlying extrinsic and intrinsic factors. The ultimate aim of this project is to improve the understanding of the genomic basis of Sulawesi’s endemic freshwater snail radiation and which role trophic specialization has played in shaping the present-day fauna inhabiting the ancient Malili lake system as well as Lake Poso. Here, genomic data derived from whole-genome sequencing will be generated for all Tylomelania species, i.e. riverine and lacustrine taxa, and representatives of its sister genus Pseudopotamis. These data will be used to assemble mitogenomes, but more importantly, to identify SNPs that will be used to infer a robust and dated backbone phylogeny of this genus. Derived phylogenetic relationships will help to 1) reconstruct the colonization history of Tylomelania across the island and into the lakes, 2) study the extent of hybridiziation within these lakes but also between riverine and lacustrine species, and 3) assess how morphospace (i.e. shell forms and radula morphs) has changed over time in the course of habitat transitions.