Historical biogeography and speciation in the Creole wrasses (Labridae, Clepticus )
- PDF / 404,505 Bytes
- 9 Pages / 595 x 791 pts Page_size
- 97 Downloads / 183 Views
ORIGINAL PAPER
Historical biogeography and speciation in the Creole wrasses (Labridae, Clepticus) Ricardo Beldade · J. B. Heiser · D. R. Robertson · J. L. Gasparini · S. R. Floeter · G. Bernardi
Received: 10 April 2008 / Accepted: 16 December 2008 / Published online: 1 January 2009 © The Author(s) 2008. This article is published with open access at Springerlink.com
Abstract We tested whether vicariance or dispersal was the likely source of speciation in the genus Clepticus by evaluating the evolutionary timing of the eVect of the mid-Atlantic barrier, which separates C. brasiliensis and C. africanus, and the Amazon barrier, which separates C. parrae and C brasiliensis. Genetic data from three mitochondrial genes and one nuclear gene were used. Mitochondrial genes separated Clepticus into three well supported clades corresponding to the three recognized allopatric morpho-species. All analyses provided consistent support for an initial separation (»9.68 to 1.86 mya; 4.84% sequence divergence) of the Caribbean and South Atlantic lineages, followed by a much more recent divergence
Communicated by M.I. Taylor. R. Beldade (&) · G. Bernardi Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA e-mail: [email protected] J. B. Heiser Department of Ecology and Evolutionary Biology, Stimson Hall, Cornell University, Ithaca, NY 14853, USA D. R. Robertson Smithsonian Tropical Research Institute, Panama, Unit 0948, APO AA 34002, USA J. L. Gasparini Departamento de Ecologia e Recursos Naturais, Universidade Federal do Espírito Santo, Vitória, ES 29060-900, Brazil S. R. Floeter Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina, Florianopolis, SC 88010-970, Brazil
(» 0.60 to 0.12 mya; 0.3% sequence divergence) of the Brazilian and African sister morpho-species. Both these phylogenetic events occurred well after the formation of the two barriers that currently separate those three allopatric populations. The planktonic larval duration of these species (35–49 days) and coastal pelagic habits may have facilitated dispersal by this genus across those dispersal barriers after they formed.
Introduction Allopatric speciation is thought to result from two possible mechanisms: dispersal into separate regions, or the formation of a barrier that isolates populations as a vicariant event. In both cases, gene Xow is eliminated and genetic diVerences accumulate over time, leading ultimately to speciation (Brown and Lomolino 1998; Coyne and Orr 2004). In the marine environment, many organisms, including nearly all bony reef Wshes, have life histories that include a pelagic larval stage (Leis and McCormick 2002). During this phase, larvae are subjected to transport by ocean currents and are, thus, potentially widely dispersed. However, many barriers that eliminate or restrict gene Xow have been identiWed in the marine environment. In the Atlantic ocean, those include two major breaks in adult habitat: the broad zone of Amazon–Orinoco discharge, and the deep expanse
Data Loading...
