Videlier Mathieu, Sztepanacz Jacqueline L
Am Nat. 2025 Oct;206(4):362-374. doi: 10.1086/737019. Epub 2025 Aug 18.
AbstractThe evolution of sexual dimorphism is predicted to resolve conflict that can arise from divergent evolutionary interests between sexes, enabling each sex to reach its fitness optimum. However, most of the genome is shared between sexes, which can lead to a genetic constraint for dimorphism evolution. Most studies of intersexual genetic constraints have focused on the effect of genetic correlations, , for single traits. However, multivariate studies of the matrix of intersexual genetic covariances suggest that sexual dimorphism may be more evolvable than inferred from because of the potential for indirect responses to selection from correlated traits. To comprehensively address this question, we collected and reanalyzed published estimates of using a recently developed approach to quantify the evolvability of sexual monomorphism and dimorphism. We find that across the traits and species we study, the evolvability of dimorphism is lower than that of monomorphism, but also that sexually concordant and antagonistic selection are almost equally capable of producing dimorphism. We also find that asymmetry in would affect the response to selection more in females than in males. Our results show that sexual dimorphism is more evolvable than studies of suggest and underscore that sexually antagonistic selection is not required for the evolution of sexual dimorphism.
性二态性的进化预计会解决因两性不同的进化利益而产生的冲突，使两性各自达到其适合度最优值。然而，大部分基因组在两性之间是共享的，这可能会对二态性进化形成遗传限制。大多数关于两性间遗传限制的研究都集中在单一性状的遗传相关性的影响上。然而，对两性间遗传协方差矩阵的多变量研究表明，由于相关性状对选择的间接响应潜力，性二态性可能比从单一性状遗传相关性推断的更具进化潜力。为了全面解决这个问题，我们采用一种最近开发的方法来量化性单态性和二态性的进化潜力，收集并重新分析了已发表的遗传相关性估计值。我们发现，在所研究的性状和物种中，二态性的进化潜力低于单态性，但同时性协同选择和性对抗选择产生二态性的能力几乎相当。我们还发现，遗传协方差的不对称性对雌性选择响应的影响比对雄性的影响更大。我们的结果表明，性二态性比基于遗传相关性的研究所表明的更具进化潜力，并强调性二态性的进化并不需要性对抗选择。
