Abstracts (first author)
Museum DNA reveals a drastic and recent bottleneck in the Seychelles warbler
Understanding the population history of endangered species is important for interpreting contemporary ecological processes, and of conservation high importance. We use microsatellite markers and museum specimens to examine 140 years of genetic diversity change in the Seychelles warbler (Acrocephalus sechellensis), a model system for evolutionary and conservation biology. In the 1960s this species was reduced to ca 30 individuals on a single island, but it is unknown whether it has ever been widespread and abundant. Across museum and contemporary samples, we found a 25% reduction in genetic diversity, which resulted in significant genetic structure. Using simulations we show that the warbler was bottlenecked from a large, outbred population. An ancestral effective population size of over 2,000 was reduced to less than 50 within the last century, which most likely occurred due to human disturbance. The approaches used form a powerful way of inferring population history, thus helping us to understand ecological processes and inform conservation.