Neuroscience Institute, Princeton University, Princeton, NJ 08540, USA; Department of Psychology, Princeton University, Princeton, NJ 08540, USA.
Curr Biol. 2013 Nov 4;23(21):2162-8. doi: 10.1016/j.cub.2013.09.005. Epub 2013 Oct 17.
Cooperation is central to human communication. The foundation of cooperative verbal communication is taking turns to speak. Given the universality of turn-taking, it is natural to ask how it evolved. We used marmoset monkeys to explore whether another primate species exhibits cooperative vocal communication by taking turns. Marmosets share with humans a cooperative breeding strategy and volubility. Cooperative care behaviors are thought to scaffold prosocial cognitive processes. Moreover, marmosets and other callitrichid primates are very vocal and readily exchange vocalizations with conspecifics. By measuring the natural statistics of marmoset vocal exchanges, we observed that they take turns in extended sequences and show that this vocal turn-taking has as its foundation dynamics characteristic of coupled oscillators--one that is similar to the dynamics proposed for human conversational turn-taking. As marmoset monkeys are on a different branch of the evolutionary tree that led to humans, our data demonstrate convergent evolution of vocal cooperation. Perhaps more importantly, our data offer a plausible alternative scenario to "gestural origin" hypotheses for how human cooperative vocal communication could have evolved.
合作是人类交流的核心。合作言语交流的基础是轮流发言。鉴于轮流发言的普遍性，很自然会问它是如何进化的。我们使用狨猴来探索另一种灵长类动物是否通过轮流来表现出合作的声音交流。狨猴与人类共享合作繁殖策略和健谈。合作的照顾行为被认为是支撑亲社会认知过程的基础。此外，狨猴和其他卷尾猴科的灵长类动物非常善于发声，并且很容易与同类交换叫声。通过测量狨猴叫声交换的自然统计数据，我们观察到它们在扩展序列中轮流进行，并且表明这种声音轮流以类似于为人类对话轮流提出的动态为基础——一种类似于为人类对话轮流提出的动态。由于狨猴与导致人类的进化树的不同分支，我们的数据表明声音合作的趋同进化。也许更重要的是，我们的数据为“手势起源”假说提供了一个合理的替代方案，说明人类合作的声音交流是如何进化的。
