Common ragweed (Ambrosia artemisiifolia), an annual weed native to North America, is a highly successful invader colonizing locations across Eurasia, Australia and South America. Being highly allergenic, ragweed is a substantial public health concern. In this study, researchers investigated the invasive success of ragweed in the French Alps, an area the plant reached about sixty years ago, and attempt to link the niche expansion with genetic evolution. Using GBIF-mediated occurrences of ragweed at global and regional scales, the researchers modelled climatic niches and related these to genetic structure and phenotypic architecture gathered through a large experiment, in which they analysed DNA and tracked the development of 3,000 plants. Their results identify 36 genetic markers potentially under selection, as they showed correlation with climate niche parameters, and eight of these also correlated with quantitative traits markers. The combined results point to a rapid adaptation of ragweed during its colonization of the French Alps.
Gallien L, Thuiller W, Fort N, Boleda M, Alberto FJ, Rioux D, Lainé J and Lavergne S (2016) Is There Any Evidence for Rapid, Genetically-Based, Climatic Niche Expansion in the Invasive Common Ragweed? PLOS ONE. Public Library of Science (PLoS) 11(4): e0152867. Available at doi:10.1371/journal.pone.0152867.