Amici Federica, Aureli Filippo, Call Josep
Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Earth Sciences, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool L3 3AF, United Kingdom.
Curr Biol. 2008 Sep 23;18(18):1415-9. doi: 10.1016/j.cub.2008.08.020.
The Machiavellian Intelligence or Social Brain Hypothesis explains the evolution of increased brain size as mainly driven by living in complex organized social systems in which individuals represent "moving targets" who can adopt multiple strategies to respond to one another. Frequently splitting and merging in subgroups of variable composition (fission-fusion or FF dynamics) has been proposed as one aspect of social complexity ( compare with) that may be associated with an enhancement of cognitive skills like inhibition, which allows the suppression of prepotent but ineffective responses in a changing social environment. We compared the performance of primates experiencing high levels of FF dynamics (chimpanzees, bonobos, orangutans, and spider monkeys) to that of species living in more cohesive groups (gorillas, capuchin monkeys, and long-tailed macaques) on five inhibition tasks. Testing species differing in diet, phylogenetic relatedness, and levels of FF dynamics allowed us to contrast ecological, phylogenetic, and socioecological explanations for interspecific differences. Spider monkeys performed at levels comparable to chimpanzees, bonobos, and orangutans, and better than gorillas. A two-cluster analysis grouped all species with higher levels of FF dynamics together. These findings confirmed that enhanced inhibitory skills are positively associated with FF dynamics, more than to phylogenetic relations or feeding ecology.
马基雅维利式智能或社会大脑假说解释了大脑尺寸增加的进化主要是由生活在复杂有组织的社会系统驱动的，在这种系统中，个体代表“移动目标”，他们可以采用多种策略相互应对。频繁地在组成可变的亚群体中分裂和合并（裂变 - 融合或FF动态）被认为是社会复杂性的一个方面（与……相比），这可能与诸如抑制等认知技能的增强有关，抑制能在不断变化的社会环境中抑制优势但无效的反应。我们在五项抑制任务中比较了经历高水平FF动态的灵长类动物（黑猩猩、倭黑猩猩、猩猩和蜘蛛猴）与生活在更具凝聚力群体中的物种（大猩猩、卷尾猴和食蟹猴）的表现。测试饮食、系统发育关系和FF动态水平不同的物种，使我们能够对比种间差异的生态、系统发育和社会生态解释。蜘蛛猴的表现与黑猩猩、倭黑猩猩和猩猩相当，且优于大猩猩。双聚类分析将所有具有较高FF动态水平的物种归为一组。这些发现证实，增强的抑制技能与FF动态呈正相关，而与系统发育关系或觅食生态的相关性更强。
