title: Evolutionary lessons from California plant phylogeography.
abstract: Phylogeography documents the spatial distribution of genetic lineages that result from demographic processes, such as population expansion, population contraction, and gene movement, shaped by climate fluctuations and the physical landscape. Because most phylogeographic studies have used neutral markers, the role of selection may have been undervalued. In this paper, we contend that plants provide a useful evolutionary lesson about the impact of selection on spatial patterns of neutral genetic variation, when the environment affects which individuals can colonize new sites, and on adaptive genetic variation, when environmental heterogeneity creates divergence at specific loci underlying local adaptation. Specifically, we discuss five characteristics found in plants that intensify the impact of selection: sessile growth form, high reproductive output, leptokurtic dispersal, isolation by environment, and the potential to evolve longevity. Collectively, these traits exacerbate the impact of environment on movement between populations and local selection pressures-both of which influence phylogeographic structure. We illustrate how these unique traits shape these processes with case studies of the California endemic oak, Quercus lobata, and the western North American lichen, Ramalina menziesii Obviously, the lessons we learn from plant traits are not unique to plants, but they highlight the need for future animal, plant, and microbe studies to incorporate its impact. Modern tools that generate genome-wide sequence data are now allowing us to decipher how evolutionary processes affect the spatial distribution of different kinds of genes and also to better model future spatial distribution of species in response to climate change.
authors.affiliation: Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095-7239; Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095-1496; vlsork@ucla.edu.
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Sork
authors.affiliation: Appalachian Laboratory, University of Maryland Center for Environmental Science, Frostburg, MD 21532;
authors.forename: Paul F
authors.identifier: 0000-0002-4464-8453
authors.initials: PF
authors.lastname: Gugger
authors.affiliation: Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei 430074, China;
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Chen
authors.affiliation: Institute of Plant Sciences, University of Graz, 8010 Graz, Austria.
authors.forename: Silke
authors.identifier: 0000-0002-4981-7850
authors.initials: S
authors.lastname: Werth
mesh_terms: D002140:California; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D008011:Lichens / Q000235:genetics*; D058974:Phylogeography; D029963:Quercus / Q000235:genetics*
chemical_list: D018744:DNA, Plant
keywords: California Floristic Province; comparative phylogeogeography; comparative phylogeography; glaciation; local adaptation; migration