Qu Jiapeng, Réale Denis, Fletcher Quinn E, Zhang Yanming
1Key laboratory of adaptation and evolution of plateau biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Qinghai, 810008 China.
4State Key Laboratory of Grassland Agro-ecosystems SKLGAE, Lanzhou University, Lanzhou, 730000 China.
Front Zool. 2019 Jul 8;16:26. doi: 10.1186/s12983-019-0329-6. eCollection 2019.
Animals inhabiting high altitudes consistently show slow life-histories. The pace-of-life syndrome (POLS) hypothesis posits behavioural, physiological and/or morphological traits that mediate the trade-off between current and future reproduction or survival, which have coevolved along a slow-fast life history continuum. Previous studies have shown that the life histories of plateau pikas varied across altitude, high-altitude individuals showed slow pace of life which were characterized by few litters per year with small litter sizes. Thus, we hypothesized that pikas populations at higher altitudes would also express personalities characteristic associated with slow life history, such as high sociability, low activity or aggressiveness. We tested this hypothesis by comparing the activity and docility of three plateau pika () populations distributed along an altitudinal gradient of the Tibetan Plateau. We predicted that high-altitude pika would be more docile and less active.
The behaviour of 556 pikas, from which 120 individuals were measured at least twice, was quantified. We observed that plateau pikas at high altitudes were less active and more docile than pika at lower altitudes. Activity and docility were significantly and negatively correlated in populations from high altitudes but not in populations from low altitudes.
Our results support the POLS hypothesis, highlight the existence of personality variation among populations distributed along an altitudinal gradient and emphasise the importance of environmental selection on personality divergence.
栖息在高海拔地区的动物一直表现出缓慢的生活史。生活节奏综合征（POLS）假说提出了行为、生理和/或形态特征，这些特征介导了当前与未来繁殖或生存之间的权衡，它们沿着慢-快生活史连续体共同进化。先前的研究表明，高原鼠兔的生活史随海拔高度而变化，高海拔地区的个体生活节奏缓慢，其特征是每年产仔数少且窝仔数小。因此，我们假设高海拔地区的鼠兔种群也会表现出与缓慢生活史相关的个性特征，如高社交性、低活跃度或攻击性。我们通过比较分布在青藏高原海拔梯度上的三个高原鼠兔（）种群的活动度和温顺程度来检验这一假设。我们预测高海拔地区的鼠兔会更温顺、活跃度更低。
对556只鼠兔的行为进行了量化，其中有120只个体至少被测量了两次。我们观察到，高海拔地区的高原鼠兔比低海拔地区的鼠兔活跃度更低、更温顺。在高海拔地区的种群中，活动度和温顺程度显著负相关，而在低海拔地区的种群中则不然。
我们的结果支持了POLS假说，突出了沿海拔梯度分布的种群之间个性差异的存在，并强调了环境选择对个性分化的重要性。
