Data from: Geographical barriers and climate influence demographic history in narrowleaf cottonwoods

Second, using SSRs and putatively neutral sequenced loci, coalescent simulations indicated that populations diverged before the last glacial maximum (LGM), suggesting the presence of population structure before the LGM. Third, the LGM and subsequent warming appear to have had different influences on each of these distinct populations, with effective population size reduction in the southern extent of the range but major expansion in the north.

These results are consistent with the hypothesis that climate and geographic barriers have jointly affected the demographic history of P. angustifolia, and point the importance of both factors as being instrumental in shaping genetic variation and structure in widespread forest trees.

Usage notes

Populus angustifolia locations and SSR data This file contains all the SSR data collected for all unique P. angustifolia genotypes, formatted for the program STRUCTURE. It also contains the latitude, longitude, and elevation of the collections. PopulusAngustifoliaSSR.xlsx