Dataset Information

Contrasting plant diversification histories within the Andean biodiversity hotspot.

ABSTRACT: The Andes are the most species-rich global biodiversity hotspot. Most research and conservation attention in the Andes has focused on biomes such as rain forest, cloud forest, and páramo, where much plant species diversity is the hypothesized result of rapid speciation associated with the recent Andean orogeny. In contrast to these mesic biomes, we present evidence for a different, older diversification history in seasonally dry tropical forests (SDTF) occupying rain-shadowed inter-Andean valleys. High DNA sequence divergence in Cyathostegia mathewsii, a shrub endemic to inter-Andean SDTF, indicates isolation for at least 5 million years of populations separated by only ca. 600 km of high cordillera in Peru. In conjunction with fossil evidence indicating the presence of SDTF in the Andes in the late Miocene, our data suggest that the disjunct small valley pockets of inter-Andean SDTF have persisted over millions of years. These forests are rich in endemic species but massively impacted, and merit better representation in future plans for science and conservation in Andean countries.

SUBMITTER: Pennington RT

PROVIDER: S-EPMC2922214 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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Contrasting plant diversification histories within the Andean biodiversity hotspot.

Pennington R Toby RT Lavin Matt M Särkinen Tiina T Lewis Gwilym P GP Klitgaard Bente B BB Hughes Colin E CE

Proceedings of the National Academy of Sciences of the United States of America 20100719 31

The Andes are the most species-rich global biodiversity hotspot. Most research and conservation attention in the Andes has focused on biomes such as rain forest, cloud forest, and páramo, where much plant species diversity is the hypothesized result of rapid speciation associated with the recent Andean orogeny. In contrast to these mesic biomes, we present evidence for a different, older diversification history in seasonally dry tropical forests (SDTF) occupying rain-shadowed inter-Andean valley ...[more]

PMID: 20643954

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Dataset Information

Contrasting plant diversification histories within the Andean biodiversity hotspot.

Publications

Contrasting plant diversification histories within the Andean biodiversity hotspot.

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