Evolution and Ecology Research Centre, School of Biological and Environmental Sciences , University of New South Wales, Sydney, NSW 2052, Australia.
School of Biological and Environmental Sciences , Liverpool John Moores University, Liverpool L3 3AF, UK.
J Exp Biol. 2021 Jun 1;224(11). doi: 10.1242/jeb.240846. Epub 2021 Jun 4.
Aversive learning - avoiding certain situations based on negative experiences - can profoundly increase fitness in animal species, yet no studies have systematically quantified its repeatability. Therefore, we assessed the repeatability of aversive learning by conditioning approximately 100 zebrafish (Danio rerio) to avoid a colour cue associated with a mild electric shock. Across eight different colour conditions, zebrafish did not show consistent individual differences in aversive learning (R=0.04). Within conditions, when zebrafish were conditioned to the same colour, blue conditioning was more repeatable than green conditioning (R=0.15 and R=0.02). Overall, aversive learning responses of zebrafish were weak and variable. We speculate that the effect of aversive learning might have been too weak to quantify consistent individual differences, or directional selection might have eroded additive genetic variance. We also discuss how confounded repeatability assays and publication bias could have inflated estimates of repeatability in the literature.
回避学习——基于负面经验避免某些情境——可极大地提高动物物种的适应性，但目前尚无研究系统地量化回避学习的可重复性。因此，我们通过对大约 100 条斑马鱼（Danio rerio）进行条件训练，以避免与轻度电击相关的颜色线索，评估了回避学习的可重复性。在八种不同的颜色条件下，斑马鱼在回避学习方面没有表现出一致的个体差异（R=0.04）。在条件内，当斑马鱼被训练到相同的颜色时，蓝色的条件反射比绿色的条件反射更具有可重复性（R=0.15 和 R=0.02）。总体而言，斑马鱼的回避学习反应较弱且多变。我们推测，回避学习的效果可能太弱，无法量化一致的个体差异，或者定向选择可能已经侵蚀了加性遗传方差。我们还讨论了混淆的可重复性测定和发表偏倚如何在文献中夸大了可重复性的估计。
