Should I stay or should I go? The Ectodysplasin locus is associated with behavioural differences in threespine stickleback.
Adaptive divergence may be facilitated if morphological and behavioural traits associated with local adaptation share the same genetic basis. It is therefore important to determine whether genes underlying adaptive morphological traits are associated with variation in behaviour in natural populations. Positive selection on low-armour alleles at the Ectodysplasin (Eda) locus in threespine stickleback has led to the repeated evolution of reduced armour, following freshwater colonization by fully armoured marine sticklebacks. This adaptive divergence in armour between marine and freshwater populations would be facilitated if the low allele conferred a behavioural preference for freshwater environments. We experimentally tested whether the low allele is associated with preference for freshwater by measuring the preference of each Eda genotype for freshwater versus saltwater after acclimation to either salinity. We found no association between the Eda low allele and preference for freshwater. Instead, the low allele was significantly associated with a reduced preference for the acclimation environment. This behaviour may facilitate the colonization of freshwater habitats from the sea, but could also hinder local adaptation by promoting migration of low alleles between marine and freshwater environments.
Barrett
Rowan D H
RD
Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada, V6T 1Z4. rbarrett@zoology.ubc.ca
Vines
Tim H
TH
Bystriansky
Jason S
JS
Schulte
Patricia M
PM
D000064:Acclimatization; D000818:Animals; D001522:Behavior, Animal; D053331:Ectodysplasins / Q000235:genetics*; D005618:Fresh Water; D005787:Gene Frequency; D005838:Genotype; D012623:Seawater; D023701:Smegmamorpha / Q000235:genetics
D053331:Ectodysplasins