Evolution of the additive genetic variance-covariance matrix under continuous directional selection on a complex behavioural phenotype
Evolution of the additive genetic variance-covariance matrix under continuous directional selection on a complex behavioural phenotype
复制标题
DOI：
10.1098/rspb.2015.1119
复制
发表时间：
2015-11-22
影响因子：
4.7
通讯作者：
Garland, Theodore, Jr.
中科院分区：
文献类型：
--
作者：
Careau, Vincent;Wolak, Matthew E.;Garland, Theodore, Jr.
考虑到人类引起的环境变化发生的速度，一个紧迫的挑战是确定选择可以驱动进化变化的速度。对多变量表型选择的适应性反应的一个关键决定因素是加性遗传方差协方差矩阵（G）。然而，在经历新的或改变的选择的群体中，G的知识不足以预测选择反应，因为G本身的进化方式知之甚少。我们实验评估G的变化时，密切相关的行为特征经历连续的定向选择。我们将遗传协方差张量方法应用于一个大型数据集（n = 17328人），该数据集来自一个重复的31代人工选择实验，该实验在为期6天的测试的第5天和第6天繁殖小鼠进行自愿轮跑。在前四代内，对G的这个子集的选择引起了整个矩阵中所有6天运行行为的成比例变化。选择引起的G的变化导致对选择的反应速度比预测的慢四倍。因此，选择加剧了G内的约束，限制了未来的适应性反应，这一现象可能对面临快速环境变化的种群产生深远的影响。
Given the pace at which human-induced environmental changes occur, a pressing challenge is to determine the speed with which selection can drive evolutionary change. A key determinant of adaptive response to multivariate phenotypic selection is the additive genetic variance covariance matrix (G). Yet knowledge of G in a population experiencing new or altered selection is not sufficient to predict selection response because G itself evolves in ways that are poorly understood. We experimentally evaluated changes in G when closely related behavioural traits experience continuous directional selection. We applied the genetic covariance tensor approach to a large dataset (n = 17 328 individuals) from a replicated, 31-generation artificial selection experiment that bred mice for voluntary wheel running on days 5 and 6 of a 6-day test. Selection on this subset of G induced proportional changes across the matrix for all 6 days of running behaviour within the first four generations. The changes in G induced by selection resulted in a fourfold slower-than-predicted rate of response to selection. Thus, selection exacerbated constraints within G and limited future adaptive response, a phenomenon that could have profound consequences for populations facing rapid environmental change.