Clustering of loci controlling species differences in male chemical bouquets of sympatric Heliconius butterflies

Kelsey Byers, Kathy Darragh, Sylvia Fernanda Garza, Diana Abondano Almeida, Ian Warren, Pasi Rastas, Richard Merrill, Stefan Schulz, W. Owen McMillan & Chris Jiggins
The degree to which loci promoting reproductive isolation cluster in the genome – i.e. the genetic architecture of reproductive isolation - can influence the tempo and mode of speciation. Tight linkage between these loci can facilitate speciation in the face of gene flow. Pheromones play a role in reproductive isolation in many Lepidoptera species, and the role of endogenously-produced compounds as secondary metabolites decreases the likelihood of pleiotropy associated with many barrier loci. Heliconius butterflies...
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