Centre for Biodiversity Dynamics, Department of Biology, NTNU, Trondheim, Norway.
UK Centre for Ecology and Hydrology, Bush Estate, Penicuik, United Kingdom.
Evolution. 2023 Oct 3;77(10):2128-2143. doi: 10.1093/evolut/qpad111.
Dissecting joint micro-evolutionary and plastic responses to environmental perturbations requires quantifying interacting components of genetic and environmental variation underlying expression of key traits. This ambition is particularly challenging for phenotypically discrete traits where multiscale decompositions are required to reveal nonlinear transformations of underlying genetic and environmental variation into phenotypic variation, and when effects must be estimated from incomplete field observations. We devised a joint multistate capture-recapture and quantitative genetic animal model, and fitted this model to full-annual-cycle resighting data from partially-migratory European shags (${Gulosus~{}aristotelis}$) to estimate key components of genetic, environmental and phenotypic variance in the ecologically critical discrete trait of seasonal migration versus residence. We demonstrate non-negligible additive genetic variance in latent liability for migration, resulting in detectable micro-evolutionary responses following two episodes of strong survival selection. Further, liability-scale additive genetic effects interacted with substantial permanent individual and temporary environmental effects to generate complex nonadditive effects on expressed phenotypes, causing substantial intrinsic gene-by-environment interaction variance on the phenotypic scale. Our analyses therefore reveal how temporal dynamics of partial seasonal migration arise from combinations of instantaneous micro-evolution and within-individual phenotypic consistency, and highlight how intrinsic phenotypic plasticity could expose genetic variation underlying discrete traits to complex forms of selection.
剖析关节微进化和对环境干扰的可塑性反应需要量化关键特征表达的遗传和环境变异的相互作用成分。对于表型离散特征，这一目标尤其具有挑战性，因为需要进行多尺度分解，以揭示潜在遗传和环境变异到表型变异的非线性转换，并且必须从不完全的现场观测中估计效应。我们设计了一种联合多状态捕获-再捕获和定量遗传动物模型，并将该模型拟合到部分迁徙的欧洲海鸦（${Gulosus~{}aristotelis}$）的全年重见数据中，以估计季节性迁徙与居留这一生态关键离散特征中遗传、环境和表型方差的关键成分。我们证明了潜在迁徙倾向的加性遗传方差不可忽视，这导致在两次强烈生存选择后出现可检测的微进化反应。此外， Liability-scale 加性遗传效应与大量个体永久性和临时环境效应相互作用，对表现型产生复杂的非加性效应，导致表型尺度上存在大量内在基因-环境互作方差。因此，我们的分析揭示了部分季节性迁徙的时间动态如何源自瞬时微进化和个体内表型一致性的组合，并强调了内在表型可塑性如何使离散特征下的遗传变异容易受到复杂形式的选择。
