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Competitive environments sustain costly altruism with negligible assortment of interactions

Doncaster, C. Patrick, Jackson, Adam and Watson, Richard A. (2013) Competitive environments sustain costly altruism with negligible assortment of interactions Scientific Reports, 3, (2836), pp. 1-6.

Record type: Article


Competition hinders the evolution of altruism amongst kin when beneficiaries gain at the expense of competing relatives. Altruism is consequently deemed to require stronger kin selection, or trait-selected synergies, or elastic population regulation, to counter this effect. Here we contest the view that competition puts any such demands on altruism. In ecologically realistic scenarios, competition influences both altruism and defection. We show how environments that pit defectors against each other allow strong altruism to evolve even in populations with negligible kin structure and no synergies. Competition amongst defectors presents relative advantages to altruism in the simplest games between altruists and defectors, and the most generic models of altruistic phenotypes or genotypes invading non-altruistic populations under inelastic density regulation. Given the widespread inevitability of competition, selection will often favour altruism because its alternatives provide lower fitness. Strong competition amongst defectors nevertheless undermines altruism, by facilitating invasion of unrelated beneficiaries as parasites.

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Published date: 3 October 2013
Keywords: population dynamics, evolutionary ecology, evolutionary theory, social evolution
Organisations: Electronics & Computer Science, Human Development & Health, Centre for Biological Sciences


Local EPrints ID: 358307
PURE UUID: c4df89c0-fe3c-4501-a6ce-c0d33f2e47b5
ORCID for C. Patrick Doncaster: ORCID iD

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Date deposited: 09 Oct 2013 13:41
Last modified: 11 Aug 2017 08:19

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