Abstract
Human-induced and natural range expansion of species are expected to lead to different patterns of genetic diversity, which might themselves be trait dependent. Recent studies examined the molecular and quantitative genetic variation following the range expansion of three plant species. The results suggest that contrasting diversity patterns among species reflect how range expansion has occurred and the level of fragmentation of the original habitat. Unexpectedly, even introductions from a homogeneous environment do not preclude a species from adapting to a new environment and becoming invasive.