Rosati Alexandra G, Stevens Jeffrey R, Hare Brian, Hauser Marc D
Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig D-04103, Germany.
Curr Biol. 2007 Oct 9;17(19):1663-8. doi: 10.1016/j.cub.2007.08.033. Epub 2007 Sep 27.
To make adaptive choices, individuals must sometimes exhibit patience, forgoing immediate benefits to acquire more valuable future rewards [1-3]. Although humans account for future consequences when making temporal decisions [4], many animal species wait only a few seconds for delayed benefits [5-10]. Current research thus suggests a phylogenetic gap between patient humans and impulsive, present-oriented animals [9, 11], a distinction with implications for our understanding of economic decision making [12] and the origins of human cooperation [13]. On the basis of a series of experimental results, we reject this conclusion. First, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes) exhibit a degree of patience not seen in other animals tested thus far. Second, humans are less willing to wait for food rewards than are chimpanzees. Third, humans are more willing to wait for monetary rewards than for food, and show the highest degree of patience only in response to decisions about money involving low opportunity costs. These findings suggest that core components of the capacity for future-oriented decisions evolved before the human lineage diverged from apes. Moreover, the different levels of patience that humans exhibit might be driven by fundamental differences in the mechanisms representing biological versus abstract rewards.
为了做出适应性选择,个体有时必须表现出耐心,放弃眼前的利益以获取更有价值的未来回报[1-3]。尽管人类在做出时间决策时会考虑未来的后果[4],但许多动物物种等待延迟奖励的时间仅为几秒[5-10]。因此,当前的研究表明,有耐心的人类与冲动的、注重当下的动物之间存在系统发育上的差距[9, 11],这种区别对我们理解经济决策[12]和人类合作的起源[13]具有重要意义。基于一系列实验结果,我们拒绝这一结论。首先,倭黑猩猩(Pan paniscus)和黑猩猩(Pan troglodytes)表现出的耐心程度是迄今为止在其他受试动物中未见的。其次,与黑猩猩相比,人类不太愿意等待食物奖励。第三,与食物相比,人类更愿意等待金钱奖励,并且只有在面对涉及低机会成本的金钱决策时才表现出最高程度的耐心。这些发现表明,面向未来决策能力的核心组成部分在人类谱系与猿类分化之前就已经进化出来了。此外,人类表现出的不同程度的耐心可能是由代表生物奖励与抽象奖励的机制的根本差异所驱动的。