Abstract:
Climate is a potent selective force in natural populations, yet the importance of adaptation in the response of plant species to past climate change has been questioned. As many species are unlikely to migrate fast enough to track the rapidly changing climate of the future, adaptation must play an increasingly important role in their response. In this paper we review recent work that has documented climate-related genetic diversity within populations or on the micro geographical scale. We then describe studies that have
looked at the potential evolutionary responses of plant populations to future climate
change. We argue that in fragmented landscapes, rapid climate change has the potential
to overwhelm the capacity for adaptation in many plant populations and dramatically
alter their genetic composition. The consequences are likely to include unpredictable
changes in the presence and abundance of species within communities and a reduction in
their ability to resist and recover from further environmental perturbations, such as pest
and disease outbreaks and extreme climatic events. Overall, a range-wide increase in
extinction risk is likely to result. We call for further research into understanding the
causes and consequences of the maintenance and loss of climate-related genetic diversity
within populations.
