Theory maintains that when future environment is predictable, parents should adjust the phenotype of their offspring to match the anticipated environment. The plausibility of positive anticipatory parental effects is hotly debated and the experimental evidence for the evolution of such effects is currently lacking. We experimentally investigated the evolution of anticipatory maternal effects in a range of environments that differ drastically in how predictable they are. Populations of the nematode Caenorhabditis remanei, adapted to 20°C, were exposed to a novel temperature (25°C) for 30 generations with either positive or zero correlation between parent and offspring environment. We found that populations evolving in novel environments that were predictable across generations evolved a positive anticipatory maternal effect, because they required maternal exposure to 25°C to achieve maximum reproduction in that temperature. In contrast, populations evolving under zero environmental correlation had lost this anticipatory maternal effect. Similar but weaker patterns were found if instead rate‐sensitive population growth was used as a fitness measure. These findings demonstrate that anticipatory parental effects evolve in response to environmental change so that ill‐fitting parental effects can be rapidly lost. Evolution of positive anticipatory parental effects can aid population viability in rapidly changing but predictable environments.

中文翻译：

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环境变化介导了预期的父母效应的演变。

理论认为，当未来的环境是可预测的时，父母应调整其后代的表型以匹配预期的环境。积极的预期父母效应的合理性引起了激烈的争论，目前尚缺乏这种效应演变的实验证据。我们通过实验研究了预期的母体效应在一系列环境中的演变，这些环境在可预测性上存在很大差异。雷曼线虫的种群适应20°C的温度，暴露于新温度（25°C）达30代，父母与后代环境之间呈正相关或零相关。我们发现，在新的环境中进化的种群可以世代相传，因此产生了积极的预期母体效应，因为他们需要母体暴露于25°C才能在该温度下获得最大繁殖。相反，在零环境相关性条件下进化的种群失去了这种预期的母体效应。如果将比率敏感型人口增长用作适应性指标，则会发现相似但较弱的模式。这些发现表明，预期的父母效应会随着环境变化而发展，因此不良的父母效应会迅速消失。