Brooks R
School of Tropical Biology, James Cook University, Townsville, Queensland, Australia.
Nature. 2000 Jul 6;406(6791):67-70. doi: 10.1038/35017552.
Indirect selection of female mating preferences may result from a genetic association between male attractiveness and offspring fitness. The offspring of attractive males may have enhanced growth, fecundity, viability or attractiveness. However, the extent to which attractive males bear genes that reduce other fitness components has remained unexplored. Here I show that sexual attractiveness in male guppies (Poecilia reticulata) is heritable and genetically correlated with ornamentation. Like ornamentation, attractiveness may be substantially Y-linked. The benefit of mating with attractive males, and thus having attractive sons, is opposed by strong negative genetic correlation between attractiveness and both offspring survival and the number of sons maturing. Such correlations suggest either antagonistic pleiotropy between attractiveness and survival or linkage disequilibrium between attractive and deleterious alleles. The presence of many colour pattern genes on or near the non-recombining section of the Y chromosome may facilitate the accumulation of deleterious mutations by genetic hitchhiking. These findings show that genes enhancing sexual attractiveness may be associated with pleiotropic costs or heavy mutational loads.
雌性交配偏好的间接选择可能源于雄性吸引力与后代适合度之间的遗传关联。有吸引力的雄性的后代可能具有更强的生长、繁殖力、生存能力或吸引力。然而，有吸引力的雄性携带降低其他适合度成分的基因的程度仍未得到探索。在这里，我表明雄性孔雀鱼（孔雀花鳉）的性吸引力是可遗传的，并且与装饰性存在遗传相关性。与装饰性一样，吸引力可能在很大程度上与Y染色体有关。与有吸引力的雄性交配并因此拥有有吸引力的儿子的好处，被吸引力与后代存活率以及成熟儿子数量之间强烈的负遗传相关性所抵消。这种相关性表明吸引力与生存之间存在拮抗多效性，或者有吸引力的等位基因与有害等位基因之间存在连锁不平衡。Y染色体非重组区域上或附近存在许多颜色模式基因，可能通过遗传搭便车促进有害突变的积累。这些发现表明，增强性吸引力的基因可能与多效性成本或沉重的突变负荷有关。
