Dispersal Capacity Rather Than Shared Environmental Constraints Determines Taxon-Specific Demographic Dynamics in an...

Area of Science:

• Ecology
• Evolutionary Biology
• Genetics

Background:

• Alpine lakes offer unique settings to study population fragmentation.
• Diving beetles (Dytiscidae) are key macroinvertebrates in these ecosystems.
• Understanding population connectivity is crucial for conservation in fragmented habitats.

Purpose of the Study:

• Investigate genetic connectivity, demographic history, and eco-evolutionary dynamics in four diving beetle species.
• Assess how dispersal capacity influences population responses to fragmented alpine lake systems.
• Examine the relationship between intra-specific genetic diversity and community structure.

Main Methods:

• Integrated genomic, morphological, and community data.
• Comparative multi-taxon approach using four diving beetle species.
• Demographic reconstructions and paleoclimatic inferences.

Main Results:

• Substantial heterogeneity in demographic responses to lake fragmentation observed.
• Higher wing loading correlated with increased genetic differentiation.
• Peripheral populations showed lower genetic diversity; populations experienced declines since the Last Glacial Maximum.
• Some populations underwent bottlenecks during warmer, drier periods.
• Community diversity (alpha and beta) was decoupled from intra-specific genetic diversity.

Conclusions:

• Interspecific differences in dispersal capacity are key drivers of demographic trajectories in alpine lakes.
• Wing loading influences genetic connectivity and population diversity.
• Species' demographic histories are decoupled from community-level dynamics.
• Multi-taxon studies are vital for understanding alpine ecosystem dynamics under climate change.