Persistence and stability of Eastern Afromontane forests: evidence from brevicipitid frogs

• Autores: Loader, Simon P.; Ceccarelli, Fadia Sara; Menegon, Michele; Howell, Kim M.; Kassahun, Roman; Mengistu, Abebe A.; Saber, Samy A.; Gebresenbet, Fikirte; de Sa, Rafael; Davenport, Tim R. B.; Larson, Joanna G.; Müller, Hendrik; Wilkinson, Mark; Gower, David J.
• Año de publicación: 2014
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Africa; Biogeography; Brevicipitidae
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Aim: The persistence and stability of habitats through time are considered predictors of high levels of biodiversity in some environments. Long-term habitat persistence and stability may explain the species-rich, endemic forest fauna and flora of the Eastern Afromontane Biodiversity Region (EABR). Using complementary phylogenetic and biogeographical approaches, we examine evolutionary patterns in EABR brevicipitid frogs. Using these data, we test whether brevicipitid history reflects patterns of long-term forest persistence and/or stability across the EABR. Location: East Africa. Methods: A dated phylogeny for brevicipitids was constructed using two nuclear and three mitochondrial markers. Alternative diversification models were used to determine signal for constant or varying net diversification rates. Using our dated tree, we identified areas of high phylogenetic diversity (PD), and inferred ancestral areas using likelihood and Bayesian approaches. Results: Brevicipitids have a long history, with generic diversification among extant lineages pre-dating the Oligocene (> 33 Ma). Ancestral-area reconstructions indicate the presence of brevicipitids in the EABR since the Oligocene, and support a scenario of palaeoendemics surviving in EABR refugia. Ancestral-area reconstructions indicate that the central Eastern Arc Mountains (EAM) formed the initial centre of diversification of forest brevicipitids. Measures of PD show that diversity varies across the EABR but is highest in the EAM. Constant net diversification rate in brevicipitids is a significantly better fit than alternative, rate-variable models. Main conclusions: The degree of persistence of forest habitats appears to be a contributing factor to the varying levels of diversity across the EABR in brevicipitids (and other organisms). In contrast to the Southern Highlands and Ethiopian Bale Mountains, the EAM stands out as an area that enabled the constant accumulation of brevicipitid species over a long period of time.
Fil: Loader, Simon P.. Universidad de Basilea; Suiza
Fil: Ceccarelli, Fadia Sara. Universidad de Basilea; Suiza. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Menegon, Michele. Museo delle Scienze di Trento; Italia
Fil: Howell, Kim M.. University of Dar es Salaam; Tanzania
Fil: Kassahun, Roman. Ethiopian Wildlife Conservation Authority; Etiopía
Fil: Mengistu, Abebe A.. Adama Science and Technology University; Etiopía
Fil: Saber, Samy A.. Al-Azhar University; Egipto
Fil: Gebresenbet, Fikirte. Oklahoma State University; Estados Unidos
Fil: de Sa, Rafael. University of Richmond; Estados Unidos
Fil: Davenport, Tim R. B.. Wildlife Conservation Society; Tanzania
Fil: Larson, Joanna G.. Harvard University; Estados Unidos
Fil: Müller, Hendrik. Universitat Jena; Alemania
Fil: Wilkinson, Mark. Natural History Museum; Reino Unido
Fil: Gower, David J.. Natural History Museum; Reino Unido