Premium
Replicated radiations of the alpine genus A ndrosace (Primulaceae) driven by range expansion and convergent key innovations
Author(s) -
Roquet Cristina,
Boucher Florian C.,
Thuiller Wilfried,
Lavergne Sébastien
Publication year - 2013
Publication title -
journal of biogeography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 158
eISSN - 1365-2699
pISSN - 0305-0270
DOI - 10.1111/jbi.12135
Subject(s) - biological dispersal , biology , biogeography , convergent evolution , origination , evolutionary biology , cladogenesis , ecology , genus , diversification (marketing strategy) , primulaceae , clade , semelparity and iteroparity , geography , phylogenetics , life history , demography , computer network , marketing , sociology , gene , computer science , business , population , biochemistry
Aim We still have limited understanding of the contingent and deterministic factors that have fostered the evolutionary success of some species lineages over others. We investigated how the interplay of intercontinental migration and key innovations promoted diversification of the genus A ndrosace . Location Mountain ranges and cold steppes of the N orthern H emisphere. Methods We reconstructed ancestral biogeographical ranges at regional and continental scales by means of a dispersal–extinction–cladogenesis analysis using dated B ayesian phylogenies and contrasting two migration scenarios. Based on diversification analyses under two frameworks, we tested the influence of life form on speciation rates and whether diversification has been diversity‐dependent. Results We found that three radiations occurred in this genus, at different periods and on different continents, and that life form played a critical role in the history of A ndrosace . Short‐lived ancestors first facilitated the expansion of the genus' range from A sia to E urope, while cushions, which appeared independently in A sia and E urope, enhanced species diversification in alpine regions. One long‐distance dispersal event from E urope to N orth A merica led to the diversification of the nested genus D ouglasia . We found support for a model in which speciation of the North A merican– E uropean clade is diversity‐dependent and close to its carrying capacity, and that the diversification dynamics of the North A merican subclade are uncoupled from this and follow a pure birth process. Main conclusions The contingency of past biogeographical connections combined with the evolutionary determinism of convergent key innovations may have led to replicated radiations of A ndrosace in three mountain regions of the world. The repeated emergence of the cushion life form was a convergent key innovation that fostered radiation into alpine habitats. Given the large ecological similarity of A ndrosace species, allopatry may have been the main mode of speciation.