© 1991 by The Society for Integrative and Comparative Biology
Evolutionary Genetics of Animal Migration1
Department of Entomology, University of California Davis, California 95616
Three primary approaches have been used to study the genetics of migration: the analyses of population differences, of single locus effects, and of polygenic influences. Studies of populations reared under similar conditions in "common garden" experiments frequently reveal gene effects contributing to differences in migratory tendency. Single locus effects are known, but are not common, a result to be expected given that migration is complex. Quantitative genetic studies reveal that heritabilities for migration related traits are often high (approximately 0.5 or more) suggesting significant amounts of genetic variation on which natural selection can act. Analyses of genetic correlations demonstrate that migratory behavior is part of a syndrome that includes aspects of both physiology and life history traits. The latter are characteristically those which contribute to colonizing ability. Migratory behavior thus does not evolve in isolation. New migration patterns are still evolving, as would be predicted from observed environmental changes and the genetic variation present in migratory species.