Data from: Distance, elevation, and environment as drivers of diversity and divergence in bumble bees across latitude and altitude

Identifying drivers of dispersal limitation and genetic differentiation is
a key goal in biogeography. We examine patterns of population connectivity
and genetic diversity using Restriction-site Associated DNA sequencing
(RADseq) in two bumble bee species, Bombus vosnesenskii and Bombus
bifarius across latitude and altitude in mountain ranges from California,
Oregon, and Washington, U.S.A. Bombus vosnesenskii, which occurs across a
broader elevational range at most latitudes, exhibits little population
structure while B. bifarius, which occupies a relatively narrow higher
elevation niche across most latitudes, exhibits much stronger population
differentiation, although gene flow in both species is best explained by
isolation with environmental niche resistance. A relationship between
elevational habitat breadth and genetic diversity is also apparent, with
B. vosnesenskii exhibiting relatively consistent levels of genetic
diversity across its range, while B. bifarius has reduced genetic
diversity at low latitudes, where it is restricted to high elevation
habitat. The results of this study highlight the importance of the
intersect between elevational range and habitat suitability in influencing
population connectivity and suggest that future climate warming will have
a fragmenting effect even on populations that are presently well
connected, as they track their thermal niches upward in montane systems.