Limited Range-Filling Among Endemic Forest Herbs of Eastern North America and Its Implications for Conservation With Climate Change

Biodiversity hotspots host a high diversity of narrowly distributed endemic species, which are increasingly threatened by climate change. In eastern North America, the highest concentration plant and endemism occurs in Southern Appalachian Mountains (SAM). It has been hypothesized that this region served as refugium during Pleistocene glacial cycles postglacial migration northward was dispersal limited. We tested hypothesis using species distribution models for eight forest herb species. also quantified extent to geography suitable habitat shifted away from current range with developed four SAM co-occur same habitats but have broader ranges. For widespread we built (1) all occurrences (2) only those overlap hotspot order evaluate Hutchinsonian shortfalls potential predict beyond SAM. evaluated predicted climatically areas projected shift their ranges under future detected unoccupied regions up 1,100 km north species’ Endemic disjunct northern due ?100–150 gap unsuitable habitat. Under change, severe reductions within non-endemic found similar overall patterns unsuitability geographic location. Our results suggest history limitation following last maximum along an environmental barrier migration. Conservation would likely require intervention assisted New England Canada.