Diversification history and morphological evolution of larks

Larks (Alaudidae) constitute one of the avian families best adapted to xeric environments, having colonized a wide suite of open habitats including deserts. Although their highest diversity is in Africa, larks occur on all nonpolar continents. We tested whether larks exhibit exceptional and/or corre...

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Detalles Bibliográficos
Autores: García-Navas, Vicente, Stervander, Martin, Alström, Per
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/394255
Acceso en línea:http://hdl.handle.net/10261/394255
Access Level:acceso abierto
Palabra clave:Africa
Alaudidae
Avian radiation
Biogeography
Ecomorphology
Lineage diversification
Open habitats
Tempo and mode
Descripción
Sumario:Larks (Alaudidae) constitute one of the avian families best adapted to xeric environments, having colonized a wide suite of open habitats including deserts. Although their highest diversity is in Africa, larks occur on all nonpolar continents. We tested whether larks exhibit exceptional and/or correlated shifts in the tempos of speciation and ecological trait diversification in the face of open ecological space. We employed a near-complete phylogeny and a morphological dataset including several recently recognized species. We found homogeneity in diversification dynamics across the family and evidence for a diversity‐dependent slowdown in cladogenesis, which indicates that Alaudidae may approach their ‘ecological limit’. We did not observe an early burst in phenotypic diversification, as would be expected in a ‘classic’ adaptive radiation. Our findings suggest that the morphology of larks shows a high level of evolutionary conservatism and overall lack of ecomorphological convergence: ecological variables (diet and habitat)—which by contrast display a higher lability—explain little of shape/size variation except beak shape. Both adaptation to aridity and dietary transitions have evolved independently in multiple lineages across subfamilies. This study supports the idea that continental radiations in open habitats may reach an equilibrium faster than those in tropical forests, due to differences in ecological opportunities.