Historical Demography and Diversity of a Tropical Rainforest Fauna

为什么有些地方的物种比其他地方多？是什么原因导致一个地方的物种与另一个地方不同？这些问题几十年来一直令生物学家着迷，目前的相互作用和进化史似乎都起到了作用。该项目结合古生态、遗传和群落多样性的证据，研究更新世气候变化对澳大利亚东北部热带雨林青蛙和蜥蜴物种的影响。以前的研究表明，这些热带雨林在晚更新世寒冷干燥的时期收缩，依赖热带雨林生存的脊椎动物经历了不同规模的范围变化和灭绝。据预测，最局限于山地雨林和目前气候范围最窄的物种对热带雨林的波动最敏感。这一假设将使用分子证据、物种分布数据和生态建模的组合进行验证，并特别关注三个协会-溪流繁殖的青蛙、陆地繁殖的小水蛙和林地小鱼。通过展示单个物种如何应对过去的气候变化，该项目将揭示为什么热带雨林群落有如此多的物种，并且在不同的地方有如此大的差异。通过增加我们对历史和当前生态如何相互作用的理解，结果将改善对其他不同但不太为人所知的热带生物群中生物多样性的预测。由于这些和其他山地物种预计将受到全球变暖的威胁，了解哪些类群对过去的气候变化敏感及其原因将有助于形成保护计划。

Why do some places have more species than others? What causes one place to have a different set of species to another? These questions have fascinated biologists for decades and it seems that both current interactions and evolutionary history play a role. This project combines evidence on paleo-ecology, genetic and community diversity to examine the effects of Pleistocene climate change on the frogs and lizards species of the tropical rainforests of north-eastern Australia. Previous research has shown that these rainforests contracted under cold, dry periods of the late Pleistocene and that the rainforest-dependent vertebrates underwent range changes and extinctions at varying scales. It is predicted that species most restricted to montane rainforests and with the narrowest current climatic range have been the most sensitive to rainforest fluctuations. This hypothesis will be tested using a combination of molecular evidence, species' distribution data and ecological modeling and with particular attention to three guilds - stream-breeding frogs, terrestrial-breeding microhylid frogs and forest-floor skinks. By showing how individual species responded to past climate change, the project will shed light on why rainforest communities have so many species and vary so much from place to place. By increasing our understanding of how history and current ecology interact, the results will improve prediction of biodiversity in other diverse, but less well known tropical biotas. As these and other montane species are expected to be threatened by global warming, knowing which taxa were sensitive to past climate change and why will help to form plans for conservation.