Testing biogeographic hypotheses in Wallacea using freshwater molluscs

亚洲大陆架和澳大利亚大陆架之间被称为Wallacea的海洋岛屿区域的地理学已经争论了近150年。该地区的地质极其复杂，特别是印度尼西亚苏拉威西岛的某些部分通常被认为是澳大利亚的起源。特别是，苏拉威西岛的一些分类群被认为是从澳大利亚大陆碎片（英语：continental fragments）上到达的。然而，这个有趣的假设从未经过严格的检验。地质学家不同意这些珊瑚虫是否是在从澳大利亚漂流时被淹没的，从生物学的角度来看，大多数群体不适合进行各自的分析，因为海洋或空气传播的替代假设通常不能被拒绝。我们的目标是使用几个淡水腹足类类群的分子生物学（i）寻求第一个确凿的证据foran澳大利亚原产的群体与一个臭名昭著的穷人的传播潜力在苏拉威西岛和（ii）应用分子钟的方法，以相关的到来，这些腹足类在岛上的候选人的年龄，从而确定最有可能的鱼。该项目的成果预计将为该地区高度复杂的地理学提供一般性的贡献，并可能通过指出某些岩石的陆上漂移的可能性，为地质学家提供跨学科的见解。

The biogeography of the oceanic island region called Wallacea between the Asian and Australiancontinental shelves has been controversely discussed for almost 150 years. The geology of the regionis extremely complex and an Australian origin of some parts of the Indonesian island Sulawesi inparticular is generally assumed. Specifically, some taxa of Sulawesi are believed to have arrived oncontinental fragments (terranes) from Australia. This intriguing assumption has never been rigorouslytested, though. Geologists disagree on whether these terranes were submerged during their drift fromAustralia, and from a biological perspective most groups are not suited for respective analyses, as thealternative hypothesis of oceanic or airborne dispersal can often not be rejected. We aim to usemolecular phylogenies of several freshwater gastropod taxa to (i) seek the first conclusive evidence foran Australian origin of groups with a notoriously poor dispersal potential on Sulawesi and (ii) to apply amolecular clock approach in order to correlate the arrival of these gastropods on the island with theage of the candidate terranes, and thus identify the most likely terrane. The outcome of this project isexpected to provide a general contribution to the highly complex biogeography of the region and mayalso yield interdisciplinary insights for geologists by indicating the probabality of a subaerial drift ofcertain terranes.