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Updated: Aug 30, 2026

Monitoring Spatial Segregation in Surface Colonizing Microbial Populations
Published on: October 29, 2016
Viscous populations and their support for reciprocal cooperation
James A R Marshall1, Jonathan E Rowe
1Department of Earth Science and Engineering, Imperial College London, London, SW7 2AZ, UK. James.A.Marshall@imperial.ac.uk
Abstract:
Viscous populations (those whose members are spatially distributed and have limited mobility and locality of interaction and mating) have been proposed to support the evolution of reciprocal cooperation among self-interested individuals. Here we present a model of such a population and describe how its examination yielded the realization that different classes of viscous populations exist with differing levels of support for reciprocal cooperation. Specifically we find from our model that, in a spatially distributed population with increased viscosity, the reciprocally cooperative tit-for-tat strategy may not be globally stable due to a corresponding increase in local population density.
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