Highlighted Young PPE Member of the Month
Dr. Billie Gould Goul, B, DA Moeller, VM Eckhart, P Tiffin, E Fabio, and MA Geber. 2014. Localadaptation and range boundary formation in response to complex environmental gradients across the geographical range of Clarkia xantiana ssp. Xantiana. Journal of Ecology 102:95-107. A long standing challenge in plant ecology and evolution is identifying the forces limiting species geographic distributions. For some species, geographic ranges are clearly limited by physical dispersal barriers, but in the absence of barriers adaptation may be limited by lack of adaptive trait variation. In this study we examined patterns of differentiation across the majority of the geographic range of a California endemic wildflowr, Clarkia xantiana ssp. xantiana. We found that edge populations are well differentiated from central ones, and despite evidence of locally adaptive selection, heritable variation is not reduced in edge populations. These results challenge the idea that lack of adaptation at species range edges is driven largely by patterns of selection and gene flow across a heterogeneous landscape. A link to the paper and more about Billie’s work can be found here.