Parallel and convergent evolution in genes underlying seasonal migration.

Area of Science:

• Evolutionary Biology
• Genomics
• Ornithology

Background:

• Seasonal migration is a complex behavior with a poorly understood genetic basis.
• Previous studies show limited consensus on shared genomic regions underlying migration across species.
• The Common Yellowthroat (Geothlypis trichas) offers a model to study parallel evolution of migratory behavior due to distinct North American clades.

Purpose of the Study:

• To investigate the genetic basis of migratory phenotypes within the Common Yellowthroat.
• To identify genomic regions and genes associated with seasonal migration.
• To assess the extent of parallel or convergent evolution in migratory genes between eastern and western clades.

Main Methods:

• Genome-wide population genetic structure analysis of 196 Common Yellowthroats from 22 locations.
• Identification of selection signals by comparing resident and migratory phenotypes within and between clades.
• Analysis focused on identifying candidate genes involved in seasonal migration.

Main Results:

• Widespread support for parallel evolution at the genic level, especially in genes related to biological timekeeping.
• Limited evidence of parallelism at the individual single nucleotide polymorphism (SNP) level.
• Genetic structure analysis revealed population-level variations across the breeding range.

Conclusions:

• Parallel evolution plays a significant role in the genetic architecture of migration at the gene level.
• Multiple distinct genetic pathways likely contribute to the modulation of migratory behavior.
• Understanding the genetic basis of migration requires examining both shared and unique evolutionary trajectories.