Group dance, social cohesion, and social identity in the Yali society from Papua

Group dance to music is a ubiquitous activity performed all around the world. Considering that even our distant ancestors engaged in ritual dancing, joint dances seem to be deeply rooted in human nature. Thus many scholars have hypothesized that group dancing might serve important adaptive roles. Here, we tested this premise by exploring whether group dancing to music does indeed entail social benefits, which could explain the pervasive nature of group dancing. We conducted a non-laboratory experiment among members of the Yali, an indigenous people living in Highland Papua, an Indonesian province. In total, 180 Yali participated in the study (80 in the dance condition and 100 in the control condition), among whom 93 (52%) were women (age M = 30.36, SD = 10.36). The results showed that joint dancing led to greater prosociality, demonstrated by the sharing of a larger sum of money in the Dictator Game, and stronger social identity, shown by a higher level of in-group favoritism. So far as we know, our study is the first to provide ecologically valid and naturalistic evidence, from an experiment in which members of a traditional society participated, that supports the adaptive role of group dancing. We conclude by discussing the potential beneficial effects of group dance, including greater prosociality and a higher level of in-group favoritism.