The fate of cooperation during range expansions

Abstract

Cooperation is beneficial for the species as a whole, but, at the level of an individual, defection pays off. Natural selection is then expected to favor defectors and eliminate cooperation. This prediction is in stark contrast with the abundance of cooperation at all levels of biological systems: from cells cooperating to form a biofilm or an organism to ecosystems and human societies. Several explanations have been proposed to resolve this paradox, including direct reciprocity, kin, and group selection. However, our work builds upon an observation that selection on cooperators might depend both on their relative frequency in the population and on the population density. We find that this feedback between the population and evolutionary dynamics can substantially increase the frequency of cooperators at the front of an expanding population, and can even lead to a splitting of cooperators from defectors. After splitting, only cooperators colonize new territories, while defectors slowly invade them from behind. Since range expansions are very common in nature, our work provides a new explanation of the maintenance of cooperation.

References in corpus (7)

• Front propagation into unstable states
• Gene surfing
• Genetic Demixing and Evolutionary Forces in the One-Dimensional Stepping Stone Model
• Effect of spatial structure on the evolution of cooperation
• Selective sweeps in growing microbial colonies
• Fisher waves in the strong noise limit
• Competition and cooperation in one-dimensional stepping stone models

Cited by in corpus (12)

• Genetic drift opposes mutualism during spatial population expansion
• Physical Basis of Large Microtubule Aster Growth
• Spatial dynamics of synthetic microbial hypercycles and their parasites
• Evolution arrests invasions of cooperative populations
• Slow expanders invade by forming dented fronts in microbial colonies
• A mathematical formalism for natural selection with arbitrary spatial and genetic structure
• Evolutionary Dynamics with Fluctuating Population Sizes and Strong Mutualism
• Range Expansion of Heterogeneous Populations
• Cooperation in Microbial Populations: Theory and Experimental Model Systems
• Frequency-Dependent Selection at Rough Expanding Fronts
• Pinned, locked, pushed, and pulled traveling waves in structured environments
• Bifurcation to locked fronts in two component reaction-diffusion systems