Data from: Selection for associative learning of color 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.

学界目前才刚刚开始厘清，认知能力的差异如何源于对环境条件的局部适应。此领域的核心问题之一是：特定情境下对认知能力的定向选择，在多大程度上会通过相关进化，对认知能力的整体水平产生影响。为解答该问题，我们以雌性丽蝇蛹集金小蜂（Nasonia vitripennis）为实验对象，针对其视觉联想学习能力开展人工定向选择实验。我们采用将视觉刺激与寄主奖赏绑定的奖赏型条件学习范式，经过10代定向选育后，受试个体的视觉联想学习能力得到显著提升。为检验该类联想学习是否存在相关进化效应，我们同样采用奖赏型条件学习范式，以嗅觉刺激替代视觉刺激，测试雌性个体快速形成习得联想的能力。此外，我们通过为雄性个体施加交配奖赏的色彩条件化训练，评估该提升后的联想学习能力是否在两性中均有体现。相较于对照系，选择选育系的雌雄个体均表现出显著提升的联想学习能力，且该效应不受学习情境或条件刺激（Conditioned Stimulus, CS）类型的制约。选择选育系与对照系之间，未检测到脑神经纤维网相对体积的显著差异。