Patterns of animal dispersal, vicariance and diversification in the Holarctic

We analysed patterns of animal dispersal, vicariance and diversification in the Holarctic based on complete phylogenies of 57 extant non-marine taxa, together comprising 770 species, documenting biogeographic events from the Late Mesozoic to the present. Four major areas, each corresponding to a his...

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Detalles Bibliográficos
Autores: Sanmartín, Isabel, Enghoff, Henrik, Ronquist, Fredrik
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2001
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/166376
Acceso en línea:http://hdl.handle.net/10261/166376
Access Level:acceso abierto
Palabra clave:Historical biogeography
Trans-Atlantic
Trans-Beringian
Disjunct
Descripción
Sumario:We analysed patterns of animal dispersal, vicariance and diversification in the Holarctic based on complete phylogenies of 57 extant non-marine taxa, together comprising 770 species, documenting biogeographic events from the Late Mesozoic to the present. Four major areas, each corresponding to a historically persistent landmass, were used in the analyses: eastern Nearctic (EN), western Nearctic (WN), eastern Palaeoarctic (EP) and western Palaeoarctic (WP). Parsimony-based tree fitting showed that there is no significantly supported general area cladogram for the dataset. Yet, distributions are strongly phylogenetically conserved, as revealed by dispersalvicariance analysis (DIVA). DIVA-based permutation tests were used to pinpoint phylogenetically determined biogeographic patterns. Consistent with expectations, continental dispersals (WP-EP and WN-EN) are significantly more common than palaeocontinental dispersals (WN-EP and EN-WP), which in turn are more common than disjunct dispersals (EN-EP and WN-WP). There is significant dispersal asymmetry both within the Nearctic (WN+EN more common than EN+WN) and the Palaeoarctic (EP+WP more common than WP-tEP). Cross- Beringian faunal connections have traditionally been emphasized but are not more important than cross-Atlantic connections in our data set. To analyse changes over time, we sorted biogeographic events into four major time periods using fossil, biogeographic and molecular evidence combined with a 'branching clock. These analyses show that trans-Atlantic distributions (EN-WP) were common in the Early-Mid Tertiary (70-20 Myr), whereas trans- Beringian distributions (WN-EP) were rare in that period. Most EN-EP disjunctions date back to the Early Tertiary (7045 Myr), suggesting that they resulted from division of cross-Atlantic rather than cross-Beringian distributions. Diversification in WN and WP increased in the Quaternary (< 3 Myr), whereas in EP and EN it decreased from a maximum in the Early-Mid Tertiary.