On the Dynamic Persistence of Cooperation: How Lower Fitness Induces Higher Survivability

Guy Sella and Michael Lachmann

Working Papers from Santa Fe Institute

Abstract: Sub-populations of cooperators and defectors inhabit sites on a lattice. The interactions among the individuals at a site, in the form of a prisoners-dilemma (PD) game, determine their fitnesses. The PD pay-off parameters are chosen so that cooperators are able to maintain a homogeneous population, while defectors are not. Individuals mutate to become the other type and migrate to a neighboring site with low probabilities. Both density dependent and density independent versions of the model are studied. The dynamics of the model can be understood by considering the life-cycle of a population at a site. This life-cycle starts with one cooperator establishing a population. During this life-cycle new cooperator populations are founded by single cooperators that migrate out to empty neighboring sites. The system can reach a steady state where cooperation prevails if the global ``birth'' rate of populations is equal to the rate of their ``death.'' This steady state is dynamic in nature---cooperation persists although every single population of cooperators dies out. These dynamics enable the persistence of cooperation in a large section of the model's parameter space.

Submitted to Journal of Theoretical Biology

Keywords: Spatial Prisoner's Dilemma; cooperation; altruism; structured population; evolutionary transitions (search for similar items in EconPapers)
Date: 1999-03
New Economics Papers: this item is included in nep-cdm, nep-cmp, nep-gth and nep-ind
References: View complete reference list from CitEc
Citations:

There are no downloads for this item, see the EconPapers FAQ for hints about obtaining it.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:wop:safiwp:99-03-017

Access Statistics for this paper

More papers in Working Papers from Santa Fe Institute Contact information at EDIRC.
Bibliographic data for series maintained by Thomas Krichel ().