Data from: Environmental effects on the detection of adaptation

Detecting adaptation involves comparing the performance of populations evolving in different environments. This detection may be confounded by effects due to the environment experienced by organisms prior to the test. We tested whether such confounding effects occur, using spider-mite selection lines on two novel hosts and one ancestral host, after 15 generations of selection. Mites were either sampled directly from the selection lines, or subjected to a common juvenile or to a common maternal environment, mimicking the most frequent environmental manipulations. These environments strongly affected all life-history traits. Moreover, the detection of adaptation and of correlated responses on the ancestral host was inconsistent among environments in almost 20% of the cases. Indeed, we did not detect responses unambiguously for any life-history trait. This inconsistency was due to differential environmental effects on lines from different selection regimes. Therefore the detection of adaptation requires a careful control of these environmental effects.适应性检测需通过比较不同演化环境下种群的表现性能来实现。但此类检测结果可能会因受试生物在实验前所处的环境效应而出现混淆。本研究以在两种新宿主（novel hosts）与一种祖先宿主（ancestral host）上经过15代选择培育的叶螨（spider-mite）选择系（selection lines）为材料，旨在检测此类混淆效应是否存在。实验中，我们要么直接从选择系中取样叶螨，要么将其置于统一的幼期环境或统一的母代环境中培育，以模拟最常见的环境操控手段。上述环境对所有生活史性状（life-history traits）均造成了显著影响。此外，在近20%的实验案例中，针对祖先宿主的适应性检测与相关响应检测的结果在不同环境间表现出不一致性。事实上，我们未在任何生活史性状中检测到明确的响应结果。该不一致性源于不同环境对不同选择方案（selection regimes）下各选择系的差异化作用。因此，开展适应性检测需对这类环境效应进行严格管控。