Schön Ybarra M A
Am J Phys Anthropol. 1984 Jan;63(1):65-76. doi: 10.1002/ajpa.1330630109.
Positional (postural and locomotor) patterns and substrates used by the seven adults of a free-ranging troop of red howling monkeys (Alouatta seniculus) were identified and sampled during their feeding and resting. Traveling patterns and substrates were noted but not quantified. Arboreal locomotor behaviors were pronograde quadrupedalism, some leaping, bridging, lowering, and pull up. Sitting and reclining were the most frequent postures. Tail suspension and arboreal bipedal stance were used when feeding. Predominant locomotor behaviors were those in which limbs appeared to be compression stressed. There were no limbs suspensions. The monkeys used the entire tree canopy, that of the low shrubs, and did a good deal of travel on the ground. The lack of forelimb suspension is attributed to the inability of these howlers to hang beneath supports and look forward at the same time; the impediment is created by the size of the vocal organs in the neck. The locomotion of these monkeys is offered to depict that of Aegyptopithecus zeuxis.
对一群自由放养的红吼猴（Alouatta seniculus）中的七只成年个体在进食和休息时所采用的姿势（体位和运动姿势）及基质进行了识别和采样。记录了移动模式和基质，但未进行量化。树栖运动行为包括前肢前伸的四足行走、一些跳跃、跨越、下降和引体向上。坐着和躺着是最常见的姿势。进食时采用尾部悬挂和树栖双足站立姿势。主要的运动行为是那些四肢似乎承受压缩压力的行为。没有四肢悬挂行为。这些猴子利用了整个树冠层、低矮灌木的树冠层，并且在地面上进行大量移动。前肢缺乏悬挂行为归因于这些吼猴无法同时悬挂在支撑物下方并向前看；这种阻碍是由颈部发声器官的大小造成的。这些猴子的运动方式被用来描绘埃及古猿（Aegyptopithecus zeuxis）的运动方式。
