DISSERTATION RESEARCH: Scaling of work in insect societies

Arizona State University, Scottsdale AZ

Investigators

Abstract

One of the most significant traits of an animal is its body size, which has profound consequences for its structure, function, and ecology. Likewise, when animals form social groups, individual and group properties may change, or scale, in response to changes in group size. In highly social insects such as ants and bees, colony size varies tremendously, from just a few individuals up to thousands or even millions. Moreover, their colonies are so tightly integrated that they function like organisms, and may thus be subject to similar scaling relationships. This project will investigate how the organization and output of work performed by ant colonies scales with colony size. Ant colonies exhibit a division of labor in which different workers specialize on different tasks such as foraging and brood care. By manipulating colony size and measuring task performance, the researchers will test how colony size affects division of labor and other patterns of activity in the seed-harvester ant Pogonomyrmex californicus. Preliminary evidence suggests that as colony size increases, division of labor increases. The project will also analyze the scaling of brood production, the major form of work output in an ant colony and a key parameter in models of social insect life history and evolution. The results will provide insights into the organization, development, and evolution of insect societies and other social groups. Social insects are among the most abundant and ecologically successful animals on earth; they also serve economically important roles (e.g., as pollinators and pests) and are leading models for the study of social behavior and complexity. In addition, the project will provide training opportunities for a graduate student and undergraduate research assistants. The investigators will also engage in public outreach based on their research, including demonstrations to K-12 students and contributions to online educational resources.