人类不只在高兴时笑，还会在社交场合发出附和他人的笑声。英国一项最新研究显示，黑猩猩也有这个本领，它们能够模拟同伴的笑声并将此作为促进社交关系的手段。
英国朴次茅斯大学等机构研究人员在新一期美国心理学会主办的学术刊物《情感》上报告说，他们对非洲赞比亚一个野生动物保护中心数十只黑猩猩展开的研究显示，黑猩猩不仅在高兴时发出自然的笑声，在同伴发笑时还会主动模仿同伴的笑声。与人类谈话中起辅助作用的笑声一样，这种模仿同伴的笑声与自然的笑声相比较为短暂。
研究人员收集了约500个黑猩猩之间玩耍的视频片段，结果发现，如果在玩耍时有黑猩猩主动模仿同伴的笑声，那么玩耍持续的时间明显更长。此外，这些黑猩猩各自所属的群组还可分为两大类，有的组已经在一起10多年，有的组最近刚成立，结果在那些新成立的组中，黑猩猩明显有更多模仿同伴笑声的举动。
领导研究的玛丽娜·达维拉－罗斯博士说，上述事实说明，黑猩猩已经掌握了用笑声来促进社交关系的本领。在进化史上，人类和黑猩猩的共同祖先首先发展出自然发笑的能力，现在人类可以将笑声用于各种社交场合，而黑猩猩也具备这个本领，对它们的观察有助于探索这种现象的出现过程，以及与此相关的语言起源等问题。（生物谷Bioon.com）
生物谷推荐原文出处：
Emotion, Feb 28, 2011
Aping expressions? Chimpanzees produce distinct laugh types when responding to laughter of others
Davila-Ross, Marina; Allcock, Bethan; Thomas, Chris; Bard, Kim A.
Abstract
Humans have the ability to replicate the emotional expressions of others even when they undergo different emotions. Such distinct responses of expressions, especially positive expressions, play a central role in everyday social communication of humans and may give the responding individuals important advantages in cooperation and communication. The present work examined laughter in chimpanzees to test whether nonhuman primates also use their expressions in such distinct ways. The approach was first to examine the form and occurrence of laugh replications (laughter after the laughter of others) and spontaneous laughter of chimpanzees during social play and then to test whether their laugh replications represented laugh-elicited laugh responses (laughter triggered by the laughter of others) by using a quantitative method designed to measure responses in natural social settings. The results of this study indicated that chimpanzees produce laugh-elicited laughter that is distinct in form and occurrence from their spontaneous laughter. These findings provide the first empirical evidence that nonhuman primates have the ability to replicate the expressions of others by producing expressions that differ in their underlying emotions and social implications. The data further showed that the laugh-elicited laugh responses of the subjects were closely linked to play maintenance, suggesting that chimpanzees might gain important cooperative and communicative advantages by responding with laughter to the laughter of their social partners. Notably, some chimpanzee groups of this study responded more with laughter than others, an outcome that provides empirical support of a socialization of expressions in great apes similar to that of humans
