Huang Chengming, Li Youbang
Laboratory of Ecology, College of Life Science, Guangxi Normal University, Guilin, Guangxi, People's Republic of China.
Primates. 2005 Oct;46(4):261-7. doi: 10.1007/s10329-005-0130-3. Epub 2005 May 25.
Limestone hill habitats pose unique challenges to langurs. One of the characteristics of this habitat is its cliffs, which account for about 10-20% of the total area. We have never observed langurs falling from the cliffs during our 10-year field study. Five patterns of locomotion were exhibited by the white-headed langur: (1) arboreal ascent and descent, (2) arboreal quadupedalism, (3) terrestrial quadrupadelism, (4) moving on cliffs and (5) leaping on cliffs. Locomotor patterns varied according to the substrate, but terrestrial quadrupedalism accounted for more than 50% of locomotion time. Moving on cliffs and leaping on cliffs may be modes of locomotion unique to the white-headed langur, at least in terms of frequency. White-headed langurs have an intermembral index of 76 and, compared to langurs with a similar intermembral index, are more terrestrial. Further analysis indicates that greater terrestrialism may be the result of adaptation to their limestone habitat. Interestingly, white-headed langurs select caves on the cliff as their sleeping sites, and they exhibit special behaviors for exiting and entering the cave very early in the morning and late in the evening.
石山栖息地给叶猴带来了独特的挑战。这种栖息地的一个特点是其悬崖，悬崖占总面积的约10 - 20%。在我们为期10年的野外研究中，从未观察到叶猴从悬崖上掉落。白头叶猴展示出五种运动模式：(1) 树上攀爬和下降，(2) 树上四足行走，(3) 地面四足行走，(4) 在悬崖上移动，以及(5) 在悬崖上跳跃。运动模式因基质而异，但地面四足行走占运动时间的50%以上。至少就频率而言，在悬崖上移动和在悬崖上跳跃可能是白头叶猴独有的运动方式。白头叶猴的肢间指数为76，与具有相似肢间指数的叶猴相比，它们更倾向于在地面活动。进一步分析表明，更强的地面活动能力可能是对其石山栖息地适应的结果。有趣的是，白头叶猴选择悬崖上的洞穴作为它们的睡眠地点，并且它们在清晨和傍晚表现出进出洞穴的特殊行为。
