Negative genetic correlation between male sexual attractiveness and survival

Indirect selection of female mating preferences may result from a genetic a ssociation between male attractiveness and offspring fitness(1,2). The offs pring of attractive males may have enhanced growth(3-5), fecundity(3,4), vi ability(5-8) or attractiveness(4,9-11). However, the extent to which attrac tive males bear genes that reduce other fitness components has remained une xplored. Here I show that sexual attractiveness in male guppies (Poecilia r eticulata) is heritable and genetically correlated with ornamentation. Like ornamentation(12-14), attractiveness may be substantially Y-linked. The be nefit of mating with attractive males, and thus having attractive sons, is opposed by strong negative genetic correlation between attractiveness and b oth offspring survival and the number of sons maturing. Such correlations s uggest either antagonistic pleiotropy between attractiveness and survival o r linkage disequilibrium between attractive and deleterious alleles. The pr esence of many colour pattern genes on or near the nonrecombining section o f the Y chromosome may facilitate the accumulation of deleterious mutations by genetic hitchhiking(15,16). These findings show that genes enhancing se xual attractiveness may be associated with pleiotropic costs or heavy mutat ional loads.