Evolution of Swarming Behavior Is Shaped by How Predators Attack

Authored by Christoph Adami, Randal S Olson, David B Knoester

Date Published: 2016

DOI: 10.1162/artl_a_00206

Sponsors: United States National Science Foundation (NSF)

Platforms: C++

Model Documentation: Other Narrative Mathematical description

Model Code URLs: https://github.com/adamilab/eos-selfish-herd

Abstract

Animal grouping behaviors have been widely studied due to their implications for understanding social intelligence, collective cognition, and potential applications in engineering, artificial intelligence, and robotics. An important biological aspect of these studies is discerning which selection pressures favor the evolution of grouping behavior. In the past decade, researchers have begun using evolutionary computation to study the evolutionary effects of these selection pressures in predator-prey models. The selfish herd hypothesis states that concentrated groups arise because prey selfishly attempt to place their conspecifics between themselves and the predator, thus causing an endless cycle of movement toward the center of the group. Using an evolutionary model of a predatorprey system, we show that how predators attack is critical to the evolution of the selfish herd. Following this discovery, we show that density-dependent predation provides an abstraction of Hamilton ` s original formulation of domains of danger. Finally, we verify that density-dependent predation provides a sufficient selective advantage for prey to evolve the selfish herd in response to predation by coevolving predators. Thus, our work corroborates Hamilton ` s selfish herd hypothesis in a digital evolutionary model, refines the assumptions of the selfish herd hypothesis, and generalizes the domain of danger concept to density-dependent predation.

Tags

Individual-based model selection selfish herd Prey Density Fish schools Marine insect Body-size Collective behavior Mating success