A phylogenetic perspective on the distribution of plant diversity
Abstract
Phylogenetic studies are revealing that major ecological niches are more conserved through evolutionary history than expected, implying that adaptations to major climate changes have not readily been accomplished in all lineages. Phylogenetic niche conservatism has important consequences for the assembly of both local communities and the regional species pools from which these are drawn. If corridors for movement are available, newly emerging environments will tend to be filled by species that filter in from areas in which the relevant adaptations have already evolved, as opposed to being filled by in situ evolution of these adaptations. Examples include intercontinental disjunctions of tropical plants, the spread of plant lineages around the Northern Hemisphere after the evolution of cold tolerance, and the radiation of northern alpine plants into the Andes. These observations highlight the role of phylogenetic knowledge and historical biogeography in explanations of global biodiversity patterns. They also have implications for the future of biodiversity.
Footnotes
- *E-mail: michael.donoghue{at}yale.edu
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Author contributions: M.J.D. wrote the paper.
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This paper results from the Arthur M. Sackler Colloquium of the National Academy of Sciences, “In the Light of Evolution II: Biodiversity and Extinction,” held December 6–8, 2007, at the Arnold and Mabel Beckman Center of the National Academies of Sciences and Engineering in Irvine, CA. The complete program and audio files of most presentations are available on the NAS web site at www.nasonline.org/Sackler_biodiversity.
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The author declares no conflict of interest.
- © 2008 by The National Academy of Sciences of the USA
