Incomparáveis taxas de diversificação de espécies na Europa

quinta-feira, janeiro 28, 2010

Unparalleled rates of species diversification in Europe

Luis M. Valente1,2,3,*,  Vincent Savolainen2,3 and Pablo Vargas1

-Author Affiliations

1Real Jardín Botánico de Madrid, CSIC, Plaza Murillo 2, 28014 Madrid, Spain

2Imperial College London, Silwood Park Campus, Ascot, Berkshire SL5 7PY, UK

3Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK

*Author for correspondence (lvalente@rjb.csic.es).

Abstract

The most rapid species radiations have been reported from ‘evolutionary laboratories’, such as the Andes and the Cape of South Africa, leading to the prevailing view that diversification elsewhere has not been as dramatic. However, few studies have explicitly assessed rates of diversification in northern regions such as Europe. Here, we show that carnations (Dianthus, Caryophyllaceae), a well-known group of plants from temperate Eurasia, have diversified at the most rapid rate ever reported in plants or terrestrial vertebrates. Using phylogenetic methods, we found that the majority of species of carnations belong to a lineage that is remarkably species-rich in Europe, and arose at the rate of 2.2–7.6 species per million years. Unlike most previous studies that have inferred rates of diversification in young diverse groups, we use a conservative approach throughout that explicitly incorporates the uncertainties associated with phylogenetic inference, molecular dating and incomplete taxon sampling. We detected a shift in diversification rates of carnations coinciding with a period of increase in climatic aridity in the Pleistocene, suggesting a link between climate and biodiversity. This explosive radiation suggests that Europe, the continent with the world's best-studied flora, has been underestimated as a cradle of recent and rapid speciation.

diversification rate    species radiation   Europe   Dianthus   phylogeny

Footnotes

Received November 27, 2009.
Accepted January 6, 2010.
© 2010 The Royal Society

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