Predation risk is important in influencing animal behaviour. We investigated how the choice of nocturnal sleeping and diurnal resting sites by two species of primates was influenced by the most likely forms of attack (diurnal raptors and nocturnal felids). We recorded vertical and horizontal patterns of occupancy for 47 sleeping and 31 resting sites, as well as the presence of lianas or vines on trees. We compared the heights of trees used as resting or sleeping sites by the monkeys with those of 200 forest trees that the monkeys did not use. Trees used as nocturnal sleeping sites were taller than those used as diurnal resting sites, and taller than trees that the monkeys did not use. However, while trees used as diurnal resting sites were not significantly taller than non-used trees, diurnal resting sites were located on branches closer to the ground, closer to the main trunk of the tree and in trees with more lianas/vines than nocturnal sleeping sites. The differences in site location can be explained by the type of predator most likely to attack at a particular time: raptors in the day and felids at night.

中文翻译：

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被高低追捕：do叫者的夜间睡眠和昼夜休息位的差异（Alouatta nigerrima和Alouatta变色）是否反映出不同类型捕食者攻击的安全性？

捕食风险对影响动物行为很重要。我们调查了两种灵长类动物对夜间睡眠和昼夜休息位的选择如何受到最可能的攻击方式（昼夜猛禽和夜间猫科动物）的影响。我们记录了47个睡眠和31个休息点的垂直和水平占用模式，以及树木上存在藤本植物或藤本植物。我们将猴子用作休息或睡觉的树木的高度与猴子不使用的200棵森林树木的高度进行了比较。用作夜间睡眠场所的树木比用作日间休息场所的树木高，并且比猴子不使用的树木更高。但是，虽然用作日间休憩场所的树木比未使用的树木高得多，日间休息点位于离地面更近，更靠近树的主要树干的树枝上，以及比夜间睡眠点更多的藤本植物/藤本植物的树木中。地点位置的差异可以用在特定时间最有可能袭击的捕食者类型来解释：白天是猛禽，晚上是fe。