Fig. 1

A map depicting two Pinus contorta native-introduced region pairs (NIRPs, panel a). The northern NIRP is represented in blue, indicating native range locations in northern British Columbia, Canada (b), and corresponding introduced populations in Sweden (c). The southern NIRP is depicted in red, indicating native range populations in the Pacific Northwest, USA (d), and corresponding introduced populations in Patagonia (e). In Patagonia, two paired stand types (i.e., plantations and invasion fronts) were sampled and represented in red and pink, respectively.