Understanding the demographic mechanisms setting geographical range limits may be key to predicting how species’ ranges will shift under climate change. Using data from a 20+ year demographic study of two tundra plants across their latitudinal ranges in North America, I show that different demographic rates change in opposite directions (“demographic compensation”) across latitudes, which may buffer populations across the range from environmental change. However, we have also found evidence that compensation may break down suddenly once a warming tipping point has been surpassed. Evidence for local adaptation suggests tipping points may paradoxically be reached sooner at the colder rather than the warmer end of the gradient, which may lead to counterintuitive range shifts under climate change.

View YouTube video of seminar: https://youtu.be/gyfwX8J6hgE