Data from: Museum DNA reveals the demographic history of the endangered Seychelles warbler

The importance of evolutionary conservation – how understanding evolutionary forces can help guide conservation decisions – is widely recognized. However, the historical demography of many endangered species is unknown, despite the fact that this can have important implications for contemporary ecological processes and for extinction risk. Here, we reconstruct the population history of the Seychelles warbler (Acrocephalus sechellensis) – an ecological model species. By the 1960s, this species was on the brink of extinction, but its previous history is unknown. We used DNA samples from contemporary and museum specimens spanning 140 years to reconstruct bottleneck history. We found a 25% reduction in genetic diversity between museum and contemporary populations, and strong genetic structure. Simulations indicate that the Seychelles warbler was bottlenecked from a large population, with an ancestral Ne of several thousands falling to <50 within the last century. Such a rapid decline, due to anthropogenic factors, has important implications for extinction risk in the Seychelles warbler, and our results will inform conservation practices. Reconstructing the population history of this species also allows us to better understand patterns of genetic diversity, inbreeding and promiscuity in the contemporary populations. Our approaches can be applied across species to test ecological hypotheses and inform conservation.

进化保护的重要性——即明晰进化动力如何指导保护决策——已得到学界广泛认可。然而，尽管种群历史动态对当代生态过程及物种灭绝风险具有关键影响，但多数濒危物种的历史种群动态仍未被阐明。本研究以生态模式物种塞舌尔莺（Acrocephalus sechellensis）为研究对象，重建其种群历史。该物种曾在20世纪60年代濒临灭绝，但其此前的种群历史却一直鲜为人知。我们利用覆盖140年时间跨度的当代个体与博物馆标本的DNA样本，重建了该物种的种群瓶颈历史。研究发现，博物馆种群与当代种群的遗传多样性降低了25%，且种群存在显著的遗传结构分化。模拟结果显示，塞舌尔莺的种群瓶颈源自一个大型祖先种群：其祖先有效种群大小（Ne）达数千，而在近一个世纪内骤降至不足50。这种由人为活动引发的快速种群衰退，对塞舌尔莺的灭绝风险具有重要意义，本研究结果可为相关保护实践提供科学参考。重建该物种的种群历史，还有助于我们更深入地理解当代种群的遗传多样性、近交及混交模式。本研究采用的分析方法可推广至其他物种，用于检验生态学假说并为保护工作提供决策支持。