期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2019
卷号：116
期号：17
页码：8431-8436
DOI：10.1073/pnas.1901656116
出版社：The National Academy of Sciences of the United States of America
摘要：Temperate species experienced dramatic range reductions during the Last Glacial Maximum, yet refugial populations from which modern populations are descended have never been precisely located. Climate-based models identify only broad areas of potential habitat, traditional phylogeographic studies provide poor spatial resolution, and pollen records for temperate forest communities are difficult to interpret and do not provide species-level taxonomic resolution. Here we harness signals of range expansion from large genomic datasets, using a simulation-based framework to infer the precise latitude and longitude of glacial refugia in two widespread, codistributed hickories ( Carya spp.) and to quantify uncertainty in these estimates. We show that one species likely expanded from close to ice sheet margins near the site of a previously described macrofossil for the genus, highlighting support for the controversial notion of northern microrefugia. In contrast, the expansion origin inferred for the second species is compatible with classic hypotheses of distant displacement into southern refugia. Our statistically rigorous, powerful approach demonstrates how refugia can be located from genomic data with high precision and accuracy, addressing fundamental questions about long-term responses to changing climates and providing statistical insight into longstanding questions that have previously been addressed primarily qualitatively.
关键词：approximate Bayesian computation ; eastern North America ; glacial refugia ; microrefugia ; temperate trees
