School of Biological Earth and Environmental Sciences, Ecology and Evolution Research Centre, University of New South Wales, Sydney, NSW, Australia.
Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia.
Heredity (Edinb). 2024 Feb;132(2):67-76. doi: 10.1038/s41437-023-00660-3. Epub 2023 Nov 15.
Selective processes act on phenotypic variation although the evolutionary potential of a trait relies on the underlying heritable variation. Developmental plasticity is an important source of phenotypic variation, but it can also promote changes in genetic variation, yet we have a limited understanding of how they are both impacted. Here, we quantified the influence of developmental temperature on growth in delicate skinks (Lampropholis delicata) and partitioned total phenotypic variance using an animal model fitted with a genomic relatedness matrix. We measured mass for 261 individuals (n = 125, n = 136) over 16 months (n = 3002) and estimated heritability and maternal effects over time. Our results show that lizards reared in cold developmental temperatures had consistently higher mass across development compared to lizards that were reared in hot developmental temperatures. However, developmental temperature did not impact the rate of growth. On average, additive genetic variance, maternal effects and heritability were higher in the hot developmental temperature treatment; however, these differences were not statistically significant. Heritability increased with age, whereas maternal effects decreased upon hatching but increased again at a later age, which could be driven by social competition or intrinsic changes in the expression of variation as an individual's growth. Our work suggests that the evolutionary potential of growth is complex, age-dependent and not overtly affected by extremes in natural nest temperatures.
选择过程作用于表型变异，尽管一个特征的进化潜力取决于潜在的可遗传变异。发育可塑性是表型变异的一个重要来源，但它也可以促进遗传变异的改变，然而我们对它们如何同时受到影响的了解有限。在这里，我们量化了发育温度对脆弱石龙子（Lampropholis delicata）生长的影响，并使用带有基因组亲缘关系矩阵的动物模型来划分总表型方差。我们在 16 个月（n = 3002）内测量了 261 只个体（n = 125，n = 136）的体重，并随时间估计了遗传力和母性效应。我们的结果表明，在发育过程中，在寒冷发育温度下饲养的蜥蜴的体重始终高于在炎热发育温度下饲养的蜥蜴。然而，发育温度并没有影响生长速度。平均而言，在炎热的发育温度处理中，加性遗传方差、母性效应和遗传力更高；然而，这些差异并不具有统计学意义。遗传力随年龄增加而增加，而母性效应在孵化后下降，但在稍后的年龄再次增加，这可能是由社会竞争或个体生长过程中变异表达的内在变化驱动的。我们的工作表明，生长的进化潜力是复杂的，依赖于年龄，并且不会受到自然巢温极端变化的明显影响。
