Dispersal Capacity Rather Than Shared Environmental Constraints Determines Taxon-Specific Demographic Dynamics in an Alpine Lake Network

Networks of alpine lakes and ponds support unique assemblages of aquatic organisms and provide an ideal biogeographical setting for studying the evolutionary, ecological and demographic outcomes of population fragmentation. In this study, we integrate genomic, morphological and community-level data...

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Detalles Bibliográficos
Autores: Ortego, Joaquín, Franco Fuentes, Eduardo, Pallares Parraga, Susana, Carbonell Hernández, José Antonio, Caballero Fernández, Daniel, Abellán Ródenas, Pedro
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/179693
Acceso en línea:https://hdl.handle.net/11441/179693
https://doi.org/10.1111/mec.70173
Access Level:acceso abierto
Palabra clave:Alpine lakes
Demography
Diving beetles
Genetic diversity
Landscape genetics
Macroinvertebrate aquatic communities
Descripción
Sumario:Networks of alpine lakes and ponds support unique assemblages of aquatic organisms and provide an ideal biogeographical setting for studying the evolutionary, ecological and demographic outcomes of population fragmentation. In this study, we integrate genomic, morphological and community-level data within a comparative multi-taxon framework to investigate genetic connectivity, demographic trajectories and eco-evolutionary dynamics in four diving beetles (Coleoptera: Dytiscidae) representative of the macroinvertebrate assemblages inhabiting high altitude lakes in the Sierra Nevada massif, southeastern Iberia. Although the focal taxa share similar ecological requirements, primarily occupy lentic habitats and disperse by flight, our results reveal substantial heterogeneity in their demographic responses to the naturally fragmented distribution of alpine lakes. Taxa with higher wing loading exhibited stronger genetic differentiation among populations, probably due to their reduced capacity to disperse across the direct geographic distances separating lakes. Populations located at the range periphery tended to exhibit lower genetic diversity than central populations in all taxa. Demographic reconstructions showed a general decline in effective population size from the last glacial maximum (LGM) to the present. However, some populations of genetically more structured taxa went through brief bottlenecks that coincided with periods of warmer climate and lower lake levels, as inferred from local paleoclimatic reconstructions. Finally, the composition of macroinvertebrate assemblages (α-diversity and β-diversity) was not associated with intra-specific genetic diversity or differentiation, suggesting that species-level demographic trajectories and community-level dynamics are decoupled. Our findings indicate that interspecific differences in dispersal capacity outweigh shared environmental constraints in determining the contrasting demographic trajectories of the studied taxa. Collectively, these results emphasise the importance of multi-taxon approaches for understanding the dynamics of species assemblages in alpine ecosystems that are highly vulnerable to climate warming.