LACK OF STRONG LOCAL ADAPTATION IN THE ALPINE FORB CRASPEDIA LAMICOLA IN SOUTHEASTERN AUSTRALIA

Climate change will test the evolutionary potential of many narrowly distributed plants, especially in alpine environments. We test for adaptation to elevation of an alpine forb, Craspedia lamicola, across three narrow replicated elevation transects and compare findings with a recent study in the grass Poa hiemata across the same range. Low-elevation plants exhibited larger (yet fewer in number) leaves per plant compared with high-elevation plants. Reciprocal transplant and common garden experiments indicated that differences due to elevation were predominantly environmentally determined, with only a small heritable component for leaf number. Plants did not exhibit a native-site advantage in terms of survival, and selection analyses showed no association between trait variation and fitness. Patterns contrast to recent findings in the grass P. hiemata, highlighting that levels of plastic and genetic variation and responses to climate change may vary markedly between species inhabiting the same environment. Differences in adaptive potential may lead to reduced ecosystem stability and compositional changes in plant communities under continued climate change.