Investment in the public good through conditional phenotypes
of large effect



This article is corrected by:

  1. Errata: Corrigendum Volume 25, Issue 3, 599–600, Article first published online: 19 January 2012

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    The results we present are based on approximately 14 million simulated populations, generated using eight Intel Xeon CPUs, over the course of approximately 1 week.

Geoff Wild, Department of Applied Mathematics, University of Western Ontario, London, ON, Canada N6A 5B7.
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We investigate the evolution of an individual's willingness to invest in a public good (what we call, helping) in a patch-structured population with limited natal dispersal. We assume that an individual's decision to invest is informed by its dispersal status: an individual makes one decision given it is native to the patch on which it breeds, and is free to make a different decision given that it is not native to the patch on which it breeds. Unlike previous work, we assume that investment in the public good, and the public good, itself, both have a large effect on individual fecundity. Kin selection analysis reveals that only extreme investment decisions (i.e. ‘always invest’ or ‘never invest’) can be evolutionarily stable. Numerical results suggest that the evolutionary instability of the ‘never invest’ phenotype (what we call, complete nonhelping) implies the evolutionary stability of ‘always invest’ (what we call, complete helping). In addition, numerical results show that bistability of extreme phenotypes is possible, indicating that the adaptive significance of altruism, in this context, is greater than has been previously recognized. Numerical results are supported by computer simulation, and results, themselves, are briefly discussed in a concluding section.