Data from: Selection for associative learning of colour stimuli reveals correlated evolution of this learning ability across multiple stimuli and rewards.

We are only starting to understand how variation in cognitive ability can result from local adaptations to environmental conditions. A major question in this regard is to what extent selection on cognitive ability in a specific context affects that ability in general through correlated evolution. To address this question we performed artificial selection on visual associative learning in female Nasonia vitripennis wasps. Using appetitive conditioning in which a visual stimulus was offered in association with a host reward, the ability to learn visual associations was enhanced within 10 generations of selection. To test for correlated evolution affecting this form of learning, the ability to readily form learned associations in females was also tested using an olfactory instead of a visual stimulus in the appetitive conditioning. Additionally, we assessed whether the improved associative learning ability was expressed across sexes by colour-conditioning males with a mating reward. Both females and males from the selected lines consistently demonstrated an increased associative learning ability compared to the control lines, independent of learning context or conditioned stimulus. No difference in relative volume of brain neuropils was detected between the selected and control lines.

目前学界才刚刚开始阐明，认知能力的差异如何源于对环境条件的局部适应。就此而言，一项核心科学问题是：特定情境下对认知能力的定向选择，会在多大程度上通过协同进化，从全局层面影响该认知能力的整体水平。为解答这一问题，我们以雌性丽蝇蛹集金小蜂（Nasonia vitripennis）为实验对象，对其视觉联合学习能力开展了人工定向选择实验。我们采用以宿主为奖赏的奖赏性条件反射范式：将视觉刺激与宿主奖赏进行关联配对，经过10代定向选择后，受试雌性的视觉联合学习能力得到显著提升。为验证该类型学习是否存在协同进化效应，我们还在奖赏性条件反射实验中以嗅觉刺激替代视觉刺激，测试雌性个体快速形成习得性联合的能力。此外，我们通过将雄性个体的色彩刺激与交配奖赏进行条件绑定，评估这种提升的联合学习能力是否在两性中均有体现。相较于对照组，选择系的雌雄个体均持续表现出更优异的联合学习能力，且该效应不受学习情境或条件刺激类型的制约。选择系与对照组的大脑神经纤维丛相对体积未检测到显著差异。