Kawai Nobuyuki, Yasue Miyuki, Banno Taku, Ichinohe Noritaka
Graduate School of Information Science, Nagoya University, Nagoya, Japan Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
Graduate School of Information Science, Nagoya University, Nagoya, Japan Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.
Biol Lett. 2014 May;10(5):20140058. doi: 10.1098/rsbl.2014.0058.
Many non-human primates have been observed to reciprocate and to understand reciprocity in one-to-one social exchanges. A recent study demonstrated that capuchin monkeys are sensitive to both third-party reciprocity and violation of reciprocity; however, whether this sensitivity is a function of general intelligence, evidenced by their larger brain size relative to other primates, remains unclear. We hypothesized that highly pro-social primates, even with a relatively smaller brain, would be sensitive to others' reciprocity. Here, we show that common marmosets discriminated between human actors who reciprocated in social exchanges with others and those who did not. Monkeys accepted rewards less frequently from non-reciprocators than they did from reciprocators when the non-reciprocators had retained all food items, but they accepted rewards from both actors equally when they had observed reciprocal exchange between the actors. These results suggest that mechanisms to detect unfair reciprocity in third-party social exchanges do not require domain-general higher cognitive ability based on proportionally larger brains, but rather emerge from the cooperative and pro-social tendencies of species, and thereby suggest this ability evolved in multiple primate lineages.
许多非人类灵长类动物在一对一的社交互动中被观察到会进行互惠行为并理解互惠关系。最近的一项研究表明，卷尾猴对第三方互惠行为和违反互惠行为都很敏感；然而，这种敏感性是否是由其相对于其他灵长类动物更大的脑容量所证明的一般智力的作用，仍不清楚。我们假设，即使脑容量相对较小，高度亲社会的灵长类动物也会对他人的互惠行为敏感。在这里，我们表明普通狨猴能够区分在社交互动中与他人进行互惠的人类参与者和不进行互惠的参与者。当非互惠者保留了所有食物时，猴子从非互惠者那里接受奖励的频率低于从互惠者那里接受奖励的频率，但当它们观察到参与者之间的互惠交换时，它们从两个参与者那里接受奖励的频率是一样的。这些结果表明，在第三方社交互动中检测不公平互惠行为的机制并不需要基于相对较大脑容量的领域一般性更高认知能力，而是源于物种的合作和亲社会倾向，从而表明这种能力在多个灵长类谱系中进化而来。
