Environmental effects on the expression of quantitative trait loci and implications for phenotypic evolution

Abstract

Organisms in natural populations experience environmental heterogeneity over a range of temporal and spatial scales, and this heterogeneity has significant evolutionary implications. By affecting patterns of selection and the expression of genetic variation, environmental heterogeneity can play an important role in determining the evolutionary dynamics of phenotypic traits and the maintenance of genetic variation. Although mapping quantitative trait loci (the loci that underlie continuously varying quantitative traits) has a long history in agricultural and applied studies, the technique has only recently been applied to evolutionary studies. This application has made it possible to identify the specific loci underlying trait variation in different environments, to measure environmental variation in natural selection on those loci, and to test assumptions of models regarding the maintenance of genetic variation under environmentally heterogeneous selection. Here we review recent studies that have examined interactions between quantitative trait loci and ecologically relevant environments to address evolutionary questions.