Lab alumnus Dr. Pierre Gaüzère just published our study on disequilibrium trait dynamics in Global Ecology and Biogeography. The study asks whether plant communities (via their functional traits) respond quickly when climate change. One of the classic idea is that rapid change leads to lagged or disequilibrium responses, as communities struggle to ‘catch up’. We showed that actually the opposite happens in North American plant communities – trait responses are faster when climate change is stronger.

The study uses our community response diagram framework, which builds on ideas for climate tracking we published a few years ago. In brief, we compare the state of the community to the state of the environment that would be expected under equilibrium, here using the mean trait value of the community as the state.

The study uses environmental data for the last 14,000 years from climate models, and trait and community proxy data by integrating pollen records with modern trait databases for several hundred sites. You can see that during periods of more rapid change (14 – 7 Ka) the traits respond quickly, whereas during slower change (7 – 0 Ka) the traits respond slowly. There are several intriguing interpretations, the most interesting of which (for us) is that non-climate factors like humans may have played a more important role in vegetation dynamics in recent millenia.

You can read the paper at the journal or download a PDF.

The study arose from a very nice ECORE3 workshop in snowy Finse, Norway that was organized by co-Author Alistair Seddon several years ago – an inspiring place to think about changing climates!