Predicting Multivariate Responses of Sexual Dimorphism to Direct and Indirect Selection.
AbstractSexual dimorphism is often assumed to result from balancing the strength of antagonistic selection in favor of dimorphism against the degree of constraint imposed by the shared genome of the sexes, reflected in the B matrix of genetic intersexual covariances. To investigate the totality of forces shaping dimorphism, we reparameterized the Lande equation to predict changes in trait averages and trait differences between the sexes. As genetic constraints on the evolution of dimorphism in response to antagonistic selection become larger, dimorphism will tend to respond more rapidly to concordant selection (which favors the same direction of change in male and female traits) than to antagonistic selection. When we apply this theory to four empirical estimates of B in Drosophila melanogaster, the indirect responses of dimorphism to concordant selection are of comparable or larger magnitude than the direct responses of dimorphism to antagonistic selection in two suites of traits with typical levels of intersex correlation. Antagonistic selection is more important in two suites of traits where the intersex correlations are unusually low. This suggests that the evolution of sexual dimorphism may sometimes be dominated by concordant selection rather than antagonistic selection.
['Cheng 成常德|Changde|C|', 'Houle|David|D|']
D000818:Animals D005075:Biological Evolution D004331:Drosophila melanogaster D005260:Female D008297:Male D008957:Models, Genetic D012641:Selection, Genetic D012727:Sex Characteristics
sexual dimorphism B matrix G matrix sexual conflict