Caldecott J O
Folia Primatol (Basel). 1980;33(4):291-309. doi: 10.1159/000155943.
Sympatric gibbon species Hylobates lar and H. syndactylus were censused on a mountain in Malaya (West Malaysia). Habitat quality was assessed between 380- and 1,525-m altitudes. H. syndactylus was found to occur up to altitudes higher than does H. lar, and this is discussed with reference to the two species' divergent foraging strategies indicated by previous research. It is suggested that gibbons are restricted in their altitudinal range by an increasingly unfavourable ratio of food consumed to energy expended in its location, caused by a reduced food-source density and more difficult terrain at higher elevations.
在马来亚（西马来西亚）的一座山上对同域分布的长臂猿物种白掌长臂猿（Hylobates lar）和合趾猿（H. syndactylus）进行了普查。在海拔380米至1525米之间评估了栖息地质量。发现合趾猿出现的海拔高度高于白掌长臂猿，并且结合先前研究所表明的这两个物种不同的觅食策略对此进行了讨论。有人提出，长臂猿的海拔分布范围受到限制，原因是在其所处位置，食物消耗与能量消耗的比例越来越不利，这是由较高海拔处食物源密度降低和地形更加崎岖造成的。
