Evolution of sexual dimorphism in phenotypic covariance structure in Phymata

Sexual dimorphism is a consequence of both sex-specific selection and potential constraints imposed by a shared genetic architecture underlying sexually homologous traits. However, genetic architecture is expected to evolve to mitigate these constraints, allowing the sexes to approach their respective optimal mean phenotype. In additon, sex-specific selection is expected to generate sexual dimorphism of trait covariance structure (e.g. the phenotypic covariance matrix, P) but previous empirical work has not fully addressed this prediction. We compared patterns of phenotypic divergence, for three traits in 7 taxa in the insect genus Phymata (Reduviidae), to ask whether sexual dimorphism in P is common and whether its magnitude relates to the extent of sexual dimorphism in trait means. We found that sexual dimorphism in both mean and covariance structure was pervasive but also that the multivariate distance between sex-specific means was correlated with sex differences in the leading eige...

性二态性（Sexual dimorphism）是性别特异性选择以及由性同源性状共享的共同遗传结构所施加的潜在约束共同作用的结果。然而，遗传结构预计会进化以缓解这些约束，使得两性能够各自趋近其最优平均表型。此外，性别特异性选择预计会产生性状协方差结构（例如表型协方差矩阵P）的性二态性，但此前的实证研究尚未完全验证这一预测。我们对猎蝽属（Phymata，Reduviidae）7个类群的3个性状的表型分化模式进行了比较，以探究表型协方差矩阵P的性二态性是否普遍存在，以及其强度是否与性状均值的性二态程度相关。研究发现，均值与协方差结构的性二态性均广泛存在，且性别特异性均值间的多元距离与主要特征向量...