title: Reconstructing the origins of high-alpine niches and cushion life form in the genus Androsace S.L. (Primulaceae).
abstract: Relatively, few species have been able to colonize extremely cold alpine environments. We investigate the role played by the cushion life form in the evolution of climatic niches in the plant genus Androsace s.l., which spreads across the mountain ranges of the Northern Hemisphere. Using robust methods that account for phylogenetic uncertainty, intraspecific variability of climatic requirements and different life-history evolution scenarios, we show that climatic niches of Androsace s.l. exhibit low phylogenetic signal and that they evolved relatively recently and punctually. Models of niche evolution fitted onto phylogenies show that the cushion life form has been a key innovation providing the opportunity to occupy extremely cold environments, thus contributing to rapid climatic niche diversification in the genus Androsace s.l. We then propose a plausible scenario for the adaptation of plants to alpine habitats.
authors.affiliation: Université Joseph Fourier, Grenoble Cedex 9, France. flofloboucher@gmail.com
authors.forename: Florian C
authors.initials: FC
authors.lastname: Boucher
authors.forename: Wilfried
authors.initials: W
authors.lastname: Thuiller
authors.forename: Cristina
authors.initials: C
authors.lastname: Roquet
authors.forename: Rolland
authors.initials: R
authors.lastname: Douzet
authors.forename: Serge
authors.initials: S
authors.lastname: Aubert
authors.forename: Nadir
authors.initials: N
authors.lastname: Alvarez
authors.forename: Sébastien
authors.initials: S
authors.lastname: Lavergne
mesh_terms: D000222:Adaptation, Physiological; D000531:Altitude; D005075:Biological Evolution; D060365:Chloroplast Proteins / Q000235:genetics; D002980:Climate; D021901:DNA, Intergenic / Q000235:genetics; D017753:Ecosystem; D017343:Genes, Plant; D010802:Phylogeny; D029623:Primulaceae / Q000033:anatomy & histology* / Q000145:classification / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D060365:Chloroplast Proteins; D021901:DNA, Intergenic