title: Modes of competition and the fitness of evolved populations.
abstract: Competition between individuals drives the evolution of whole species. Although the fittest individuals survive the longest and produce the most offspring, in some circumstances the resulting species may not be optimally fit. Here, using theoretical analysis and stochastic simulations of a simple model ecology, we show how the mode of competition can profoundly affect the fitness of evolved species. When individuals compete directly with one another, the adaptive dynamics framework provides accurate predictions for the number and distribution of species, which occupy positions of maximal fitness. By contrast, if competition is mediated by the consumption of a common resource, then demographic noise leads to the stabilization of species with near minimal fitness.
authors.affiliation: Centre for Networks and Collective Behaviour, Department of Mathematical Sciences, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom.
authors.forename: Tim
authors.initials: T
authors.lastname: Rogers
authors.affiliation: Theoretical Physics Division, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: Alan J
authors.initials: AJ
authors.lastname: McKane
mesh_terms: D005075:Biological Evolution; D003163:Competitive Behavior; D003198:Computer Simulation; D004463:Ecology; D056084:Genetic Fitness; D008954:Models, Biological; D013269:Stochastic Processes