Individual variation in plasticity dulls transgenerational responses to stress
Individual variation in plasticity dulls transgenerational responses to stress
复制标题
DOI：
10.1111/1365-2435.13409
复制
发表时间：
2019-08-07
影响因子：
5.2
通讯作者：
Walsh, Matthew R.
中科院分区：
文献类型：
--
作者：
Gillis, Michael K.;Walsh, Matthew R.
许多研究表明，环境胁迫可以诱导生物体发生持续多代的适应性和适应不良表型变化。这种跨代的表型可塑性增强了我们对持续人为压力的长期后果的理解。在这里，我们评估内和代际表型反应的食物压力的淡水甲壳动物，水蚤。我们饲养了45个克隆的蚤状蚤，每一个高品质的栅藻和低品质（但也无毒）蓝藻（第1代）。第1代成年人产生的后代，然后饲养栅藻（第2代），生活史特征进行了测量，跨越两代。结果显示，第1代水蚤表现出降低的适合度（即，成熟延迟，繁殖输出降低，增加离合器间隔），当饲养在蓝藻的存在，而不是高品质的食物。然而，母亲的压力对后代的适应性没有明显的影响。也就是说，第二代实验水蚤具有相似的平均性状值，无论它们的母亲是否以蓝藻或高质量食物饲养。跨代生活史效应的信号被掩盖，部分原因是水蚤在对蓝藻的跨代反应方向上的广泛克隆变异（即，适应性和适应不良的可塑性）。进一步的分析表明，这种可塑性的个体差异可能是开放的选择，并可能提供一种当代适应蓝藻的手段。总之，我们的研究结果表明，跨代对环境的反应的整体实力和人口的快速进化的潜力之间的联系。可以在本文的支持信息中找到免费的简明语言摘要。
Much research has shown that environmental stress can induce adaptive and maladaptive phenotypic changes in organisms that persist for multiple generations. Such transgenerational phenotypic plasticity shrouds our understanding of the long-term consequences of ongoing anthropogenic pressures. Here, we evaluated within- and transgenerational phenotypic responses to food stress in the freshwater crustacean, Daphnia. We reared 45 clones of Daphnia pulicaria each on high-quality Scenedesmus and low-quality (but also non-toxic) cyanobacteria (generation 1). Offspring produced by generation 1 adults were then reared on Scenedesmus (generation 2), and life-history traits were measured across both generations. The results show that Daphnia in generation 1 exhibited reduced fitness (i.e., delayed maturation, lower reproductive output, increased clutch interval) when reared in the presence of cyanobacteria as opposed to high-quality food. However, maternal stress had no clear influence on the fitness of offspring. That is, Daphnia in the second experimental generation had similar mean trait values, irrespective of whether their mothers were reared on cyanobacteria or high-quality food. Signals of transgenerational life-history effects were obscured, in part, by extensive clonal variation among Daphnia in the direction of transgenerational responses to cyanobacteria (i.e., adaptive and maladaptive plasticity). Further analyses demonstrated that such individual variance in plasticity might be open to selection and potentially offer a means of contemporary adaptation to cyanobacteria. Taken together, our results denote a link between the overall strength of transgenerational responses to the environment and the potential for rapid evolution in populations. A free Plain Language Summary can be found within the Supporting Information of this article.