Intralocus tactical conflict: genetic correlations between fighters and sneakers of the dung beetle Onthophagus taurus

Males and females differ in their phenotypic optima for many traits, and since the majority of genes are expressed in both sexes, some alleles can be beneficial to one sex but harmful to the other (intralocus sexual conflict; ISC). ISC theory has recently been extended to intrasexual dimorphisms, where certain alleles may have opposite effects on the fitness of males of different morphs that employ alternative reproductive tactics (intralocus tactical conflict; ITC). Here we use a half-sib breeding design to investigate the genetic basis for ISC and ITC in the dung beetle Onthophagus taurus. We found positive heritabilities and intersexual genetic correlations for almost all traits investigated. Next, we calculated the intrasexual genetic correlation between males of different morphs for horn length, a sexually selected trait, and compared it to intrasexual correlations for naturally selected traits in both sexes. Intrasexual genetic correlations did not differ significantly between the...

诸多性状的表型最优值在雌雄个体间存在差异，且多数基因在两性中均有表达，因此部分等位基因可能对某一性别有益，却对另一性别有害（基因座内性冲突（intralocus sexual conflict, ISC））。近期，基因座内性冲突理论被拓展至种内性二态情形：某些等位基因对采用不同繁殖策略的不同形态雄性的适合度可能产生相反效应（基因座内战术冲突（intralocus tactical conflict, ITC））。本研究采用半同胞育种设计，探究蜣螂Onthophagus taurus中ISC与ITC的遗传基础。我们在所检测的几乎所有性状中均发现了正向遗传力与两性间遗传相关。随后，我们针对作为性选择性状的角长，计算了不同形态雄性间的同性遗传相关，并将其与两性中自然选择性状的同性遗传相关进行对比。种内遗传相关在……之间并未出现显著差异。