ABSTRACT

Behavioural laterality in nonhuman primates has been commonly studied in paired limb organs, and studies in unpaired organs such as tails are less common. The very limited investigations on tail laterality have focused on New World primates. We firstly investigated the lateral bias of tail wrapping in an Old World primate. From a wild group of one hundred of golden snub-nosed monkeys (Rhinopithecus roxellana), 14 adult monkeys, 7 males and 7 females, were chosen as focus animals. The data of tail wrapping in two different postures that were resting on the ground and climbing the tree trunk were collected and analyzed. The results demonstrated (1) that, when resting on the ground, the focus animals, 3 showed right-side tail-wrapping preference and 11 were ambipreferent; (2) that there was a population-level right tail-wrapping preference in climbing, and 9 of them showed right-side preference, 1 left-side preference and 4 were ambipreferent; (3) and that there were no significant sex differences on the direction and strength of tail wrapping laterality. These findings provide significant evidence for a difference of cerebral asymmetries in tail-wrapping control and would be valuable for further understanding the important function of tails in Old World primates.

摘要

非人类灵长类动物的行为偏侧性通常在成对的肢体器官中进行研究，而在不成对的器官（如尾巴）中进行的研究则较少见。关于尾巴偏侧性的非常有限的研究集中在新大陆灵长类动物上。我们首先研究了旧大陆灵长类动物尾巴包裹的横向偏向。来自野生群的一百只金丝雀猴（Rhinopithecus roxellana），选择14只成年猴子，雄性7只和雌性7只作为重点动物。收集并分析了在地面上搁置和爬树树干的两种不同姿势的绕尾数据。结果表明：（1）焦点动物在地面上休息时，有3个表现出右侧缠尾的偏好，有11个表现不佳；（2）在攀登过程中存在群体层次的右尾包裹偏好，其中有9种表现为右侧偏好，其中1种为左侧偏好，有4种为模糊偏好。（3）并且在尾部包裹侧向的方向和强度上没有明显的性别差异。