Data from: Sexual fidelity trade-offs promote regulatory variation in the prairie vole brain

Individual variation in social behavior seems ubiquitous, but we know little about how it relates to brain diversity. Among monogamous prairie voles, levels of vasopressin receptor (encoded by the gene avpr1a) in brain regions related to spatial memory predict male space use and sexual fidelity in the field. We find that trade-offs between the benefits of male fidelity and infidelity are reflected in patterns of territorial intrusion, offspring paternity, avpr1a expression, and the evolutionary fitness of alternative avpr1a alleles. DNA variation at the avpr1a locus includes polymorphisms that reliably predict the epigenetic status and neural expression of avpr1a, and patterns of DNA diversity demonstrate that avpr1a regulatory variation has been favored by selection. In prairie voles, trade-offs in the fitness consequences of social behaviors seem to promote neuronal and molecular diversity.

社会行为的个体差异普遍存在，但目前学界对其与大脑多样性之间的关联仍知之甚少。在一夫一妻制的草原田鼠中，与空间记忆相关脑区的加压素受体（vasopressin receptor，由avpr1a基因编码）水平，可预测野外雄性个体的空间利用模式与性忠诚行为。本研究发现，雄性忠诚与不忠行为的收益权衡，体现在领地入侵模式、后代父权、avpr1a基因表达以及不同avpr1a等位基因的进化适合度等特征中。avpr1a基因位点的DNA变异包含可可靠预测该基因表观遗传状态与神经表达水平的多态性；DNA多样性模式则表明，avpr1a的调控变异受到了自然选择的青睐。在草原田鼠中，社会行为所带来的适合度后果的权衡，似乎推动了神经元与分子多样性的演化。