Aureli F, de Waal F B
Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA.
Am J Primatol. 1997;41(3):213-28. doi: 10.1002/(SICI)1098-2345(1997)41:3<213::AID-AJP4>3.0.CO;2-#.
This is the first study to investigate the short-term effects of high population density on captive chimpanzees (Pan troglodytes). Subjects of the study were 45 chimpanzees living in five different groups at the Yerkes Regional Primate Research Center. The groups were observed under two conditions: 1) when they had access to both the indoor and outdoor sections of their enclosures; 2) during cold days when they were locked into the indoor runs, which reduced the available space by more than half. Under the high-density condition, allogrooming and submissive greetings decreased, but juvenile play increased. Remarkably, the rate of various forms of agonistic behavior, such as aggression, bluff charge, bluff display, and hooting, occurred less frequently under the high-density condition. This general decrease in adult social activity, including agonistic behavior, can be interpreted as an inhibition strategy to reduce opportunities for conflict when interindividual distances are reduced. This strategy is probably effective only in the short run, however. Behavioral indicators of anxiety, such as rough scratching and yawning, showed elevated rates, suggesting increased social tension under the high-density condition.
这是第一项研究高种群密度对圈养黑猩猩（黑猩猩属）短期影响的研究。该研究的对象是生活在耶基斯地区灵长类动物研究中心五个不同群体中的45只黑猩猩。这些群体在两种条件下接受观察：1）当它们可以进入其围栏的室内和室外区域时；2）在寒冷的日子里，它们被关在室内跑道，这使得可用空间减少了一半以上。在高密度条件下，相互梳理毛发和顺从问候减少，但幼崽玩耍增加。值得注意的是，各种形式的攻击行为，如攻击、虚张声势的冲锋、虚张声势的展示和鸣叫，在高密度条件下发生的频率较低。包括攻击行为在内的成年社交活动的普遍减少，可以被解释为一种抑制策略，以减少个体间距离缩小时冲突的机会。然而，这种策略可能只在短期内有效。焦虑的行为指标，如用力抓挠和打哈欠，显示出发生率升高，表明在高密度条件下社会紧张程度增加。
