Environmental stress increases the magnitude of nonadditive genetic variation in offspring fitness in the frog Crinia georgiana

When organisms encounter heterogeneous environments, selection may favor the ability of individuals to tailor their phenotypes to suit the prevailing conditions. Understanding the genetic basis of plastic responses is therefore vital for predicting whether susceptible populations can adapt and persist under new selection pressures. Here, we investigated whether there is potential for adaptive plasticity in development time in the quacking frog Crinia georgiana, a species experiencing a drying climate. Using a North Carolina II breeding design, we exposed 90 family groups to two water depth treatments (baseline and low-water) late in larval development. We estimated the contribution of additive and non-additive sources of genetic variation to early offspring fitness under both environments. Our results revealed a marked decline in larval fitness under the stressful (low-water) rearing environment, but also that additive genetic variation was negligible for all traits. However, in most ca...当生物体面临异质环境时，自然选择可能会青睐个体调整表型以适应当前环境的能力。因此，阐明可塑性响应的遗传基础，对于预测易感种群能否在新的选择压力下适应并存续至关重要。本研究以正经历气候干旱化的乔治澳蟾（Crinia georgiana）为研究对象，探究其发育时长是否存在适应性可塑性潜力。本研究采用北卡罗来纳II号（North Carolina II）育种设计，将90个家系群体在幼体发育后期置于两种水深处理（基准组与低水组）环境中培育。我们分别估算了两种环境下，加性与非加性遗传变异来源对早期子代适合度的贡献程度。研究结果显示，在胁迫性低水培育环境中，幼体适合度显著下降，但所有性状的加性遗传变异均可忽略不计。然而，在多数（原文未完整呈现）