Superorganisms represent a unique level of biological organization in which the phenotype of the reproductive unit, the colony, results from traits expressed at the level of individual workers. Because body size scaling has important consequences for cell diversity and system complexity in solitary organisms, colony size is a trait of particular interest in superorganism evolution. In some instances, division of labor and worker polymorphism scale with colony size, but in general little is known about how colony size drives differences in individual-level behavior or neural traits. Ants represent the greatest diversity of superorganisms and provide a manner of natural experiment to test trends in trait evolution across multiple instances of colony size expansion. In this study, we control for environmental differences and worker size polymorphism to test if colony size correlates with measures of foraging behavior and brain size in dolichoderine ants. We present data from 3 species ranked by colony size. Our results suggest colony size correlates with measures of exploratory behavior and brain investment, with small-colony ants showing higher exploratory drive and faster exploration rate than the larger colony species, and greater relative investment in the primary olfactory brain region, the antennal lobe, than the larger colony species.
Brain Behav Evol 2020;95:15–24

中文翻译：

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将群体大小与臭蚂蚁的觅食行为和大脑投资联系起来（Formicidae：Dolichoderinae）。

超级生物代表了生物组织的独特水平，其中生殖单位（菌落）的表型是由个体工人所表达的特征产生的。因为体型缩放对孤独生物的细胞多样性和系统复杂性具有重要影响，所以菌落的大小是超生物进化中特别令人关注的一个特征。在某些情况下，劳动和工人多态性的划分与菌落大小成正比，但总体上人们对菌落大小如何驱动个体水平行为或神经性状差异的了解甚少。蚂蚁代表了超级生物的最大多样性，并提供了一种自然实验的方式来测试跨菌落大小扩展的多个实例中性状进化的趋势。在这个研究中，我们控制环境差异和工人体型多态性，以测试菌落体的大小是否与多里奇德林蚂蚁的觅食行为和脑部大小相关。我们提供了按菌落大小排序的3个物种的数据。我们的研究结果表明，菌落的大小与探索行为和大脑投入的度量有关，小蚁群比更大的菌落具有更高的探索驱动力和更快的探索速度，而在主要嗅觉脑区域（触角叶）的相对投资则更大。较大的殖民地物种。
脑行为进化论2020; 95：15–24