Botanical Journal of the Linnean Society, 2013,
171 (1), p. 120-139 ISSN 0024-4074
With 788 species in 67 genera in the Neotropics, Arecaceae are an important ecological and economic component of the region. We review the influence of geological events such as the Pebas system, the Andean uplift and the land connections between South and Central/North America, on the historical assembly of Neotropical palms. We present a case study of the palm genus Astrocaryum (40 species) as a model for evaluating colonization and diversification patterns of lowland Neotropical taxa. We conducted a Bayesian dated phylogenetic analysis based on four low-copy nuclear DNA regions and a biogeographical analysis using the dispersal, extinction and cladogenesis model. Cladogenesis of Western Amazonian Astrocaryum spp. (c. 6 Mya) post-dated the drainage of the aquatic Pebas system, supporting the constraining role of Pebas on in situ diversification and colonization. The ancestral distribution of Astrocaryum spp. in the Guiana Shield supported the hypothesis of an old formation that acted as a source area from which species colonized adjacent regions, but an earliest branching position for Guianan species was not confidently recovered. A twofold increase in diversification rate was found in a clade, the ancestor of which occupied the Guiana Shield (c 13 Mya, a time of climatic change and Andean uplift).
Plan de classement
Sciences du monde végétal [076]
;
Etudes, transformation, conservation du milieu naturel [082]
