Local environmental conditions associated with different geographic areas may elicit variations in behavioural responses in animals, leading to concomitant differences in functional brain region volumes. We investigated the behavioural correlates of hippocampus and amygdala volumes in three sister taxa of the murid rodent genus , occurring in different environments. We used a Barnes maze to test spatial memory, dyadic encounters to test social behaviour, and histological brain sections to calculate hippocampus and amygdala volumes. Arid-occurring made fewer errors and had shorter latencies in locating the escape tunnel compared to moist grassland-occurring and in two probe trials, 48 and 96 h after the last learning trial. was more amicable than the subspecies in intra-specific dyadic encounters. had larger hippocampus and amygdala volumes than the other species. Smaller amygdala volumes were correlated with longer latencies in females for probe trial 1, but males showed similar latencies regardless of taxon. Higher amicability scores were correlated with larger amygdala volumes in all taxa. Higher amicability scores were correlated with larger hippocampus volumes in and but smaller hippocampus volumes in . Correlative relationships between spatial memory and amygdala volume appeared 48 h, but not 96 h, after the last learning trial. Local environmental conditions may influence spatial navigation, but social correlates drive regional brain size within cryptic striped mouse taxa.

中文翻译：

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条纹小鼠横纹鼠的社交能力（而非空间记忆）与区域脑容量变化相关。


与不同地理区域相关的当地环境条件可能会引起动物行为反应的变化，从而导致大脑功能区域体积的相应差异。我们研究了在不同环境中发生的鼠科啮齿动物属的三个姐妹类群中海马体和杏仁核体积的行为相关性。我们使用巴恩斯迷宫来测试空间记忆，使用二元遭遇来测试社会行为，并使用组织学大脑切片来计算海马体和杏仁核体积。与潮湿草地发生的情况相比，干旱发生的错误更少，定位逃生隧道的延迟更短，在两次探测试验中，最后一次学习试验后的 48 小时和 96 小时。在种内二元相遇中比亚种更友好。比其他物种有更大的海马体和杏仁核体积。在探索试验 1 中，较小的杏仁核体积与雌性较长的潜伏期相关，但无论分类单元如何，雄性都表现出相似的潜伏期。较高的友善度得分与所有类群中较大的杏仁核体积相关。较高的友善度分数与较大的海马体体积相关，但与较小的海马体体积相关。空间记忆和杏仁核体积之间的相关关系在最后一次学习试验后 48 小时出现，但不是 96 小时。当地环境条件可能会影响空间导航，但社会相关因素会影响神秘条纹小鼠类群中的区域大脑大小。