Integrating Past Archives of Insular Crocodylians into Diversity Baselines and Future Projections

鳄类作为大型动物的顶级捕食者，自1亿多年前出现以来，在维持全球淡水生态系统的功能方面发挥了重要作用。尽管鳄鱼在漫长的进化历史中表现出明显的恢复力，但在整个第四纪，鳄鱼的种群、分布和功能多样性都大幅减少，因为它们受到了越来越大的人为压力。这一点在岛屿上最为明显，在过去的10万年里，从加勒比海到马达加斯加再到大洋洲，几种特有的鳄鱼物种消失了，其他物种的数量也大幅度减少。众所周知，岛屿物种既特别容易灭绝，又对维持当地功能性生物多样性负有不成比例的责任，因此对其进行养护至关重要。然而，促进保护工作的第一步是了解以前损失的程度。该项目将努力解开岛屿鳄鱼灭绝过程中复杂和未知的维度，利用过去的数据为未来的政策提供信息。通过进行aDNA分析，汇编过去的物种发生档案，并使用整体方法将其纳入分布模型，我的研究旨在回答有关人类世中塑造岛屿鳄鱼种群的因素的关键问题。

As megafaunal apex predators, crocodylians have played significant roles in maintaining the functionality of global freshwater ecosystems since their emergence over 100 million years ago. Despite their demonstrable resilience over a long evolutionary history, crocodylians have experienced substantial reductions in populations, distributions and functional diversity throughout the Quaternary as they have come under intensifying anthropogenic pressures. This is most evident on islands, witnesses to the loss of several endemic crocodylian species, alongside the decimation of the populations of others, from the Caribbean to Madagascar to Oceania, over the last 100,000 years. Insular species are known to be both particularly susceptible to extinction and disproportionately responsible for the maintenance of local functional biodiversity, making their conservation of paramount importance. The first step in facilitating conservation efforts is, however, to understand the extent of previous losses. This project will endeavour to disentangle complex and untold dimensions of extinction processes in island crocodylians, using the data of the past to inform the policies of the future. By conducting aDNA analyses, compiling past archives of species occurrences and including them in distribution models using a holistic approach, my research aims to answer key questions about the factors shaping island crocodylian populations in the Anthropocene.