Thunström Maria, Kuchenbuch Paul, Young Christopher
School of Biological Sciences, Monash University, Bld 17, Wellington Rd, Clayton, VIC, 3800, Australia,
Primates. 2014 Jul;55(3):369-75. doi: 10.1007/s10329-014-0423-5. Epub 2014 Apr 27.
Behavioural research on non-vocal communication among non-human primates and its possible links to the origin of human language is a long-standing research topic. Because human language is under voluntary control, it is of interest whether this is also true for any communicative signals of other species. It has been argued that the behaviour of hiding a facial expression with one's hand supports the idea that gestures might be under more voluntary control than facial expressions among non-human primates, and it has also been interpreted as a sign of intentionality. So far, the behaviour has only been reported twice, for single gorilla and chimpanzee individuals, both in captivity. Here, we report the first observation of concealing of facial expressions by a monkey, a Barbary macaque (Macaca sylvanus), living in the wild. On eight separate occasions between 2009 and 2011 an adult male was filmed concealing two different facial expressions associated with play and aggression ("play face" and "scream face"), 22 times in total. The videos were analysed in detail, including gaze direction, hand usage, duration, and individuals present. This male was the only individual in his group to manifest this behaviour, which always occurred in the presence of a dominant male. Several possible interpretations of the function of the behaviour are discussed. The observations in this study indicate that the gestural communication and cognitive abilities of monkeys warrant more research attention.
关于非人类灵长类动物之间非语言交流的行为研究及其与人类语言起源的可能联系，是一个长期存在的研究课题。由于人类语言受自主控制，其他物种的任何交流信号是否也是如此就成为了一个有趣的问题。有人认为，用手隐藏面部表情的行为支持了这样一种观点，即对于非人类灵长类动物来说，手势可能比面部表情更受自主控制，并且这也被解释为一种意向性的标志。到目前为止，这种行为仅在圈养的单个大猩猩和黑猩猩个体中被报道过两次。在这里，我们报告了对一只生活在野外的巴巴里猕猴（猕猴属）隐藏面部表情的首次观察。在2009年至2011年期间的八个不同场合，拍摄到一只成年雄性隐藏与玩耍和攻击相关的两种不同面部表情（“玩耍脸”和“尖叫脸”），总共22次。对视频进行了详细分析，包括注视方向、手部动作、持续时间和在场个体。这只雄性是其群体中唯一表现出这种行为的个体，且这种行为总是在一只占主导地位的雄性在场时发生。讨论了该行为功能的几种可能解释。本研究中的观察结果表明，猴子的手势交流和认知能力值得更多的研究关注。
