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 Evolution of ethnocentrism on undirected and directed Barab√^√¬°si√Ę
‚^¬¨‚^ņ^‹Albert networks , Physica A

Abstract: Using Monte Carlo simulations, we study the evolution of
contingent cooperation and ethnocentrism in the one-shot game.
Interactions and reproduction among computational agents are simulated on
undirected and directed Barab√^√¬°si√Ę‚^¬¨‚^ņ^‹Albert (BA) networks. We
first replicate the Hammond√Ę‚^¬¨‚^ņ^‹Axelrod model of in-group favoritism
on a square lattice and then generalize this model on undirected and
directed BA networks for both asexual and sexual reproduction cases. Our
simulations demonstrate that irrespective of the mode of reproduction, the
ethnocentric strategy becomes common even though cooperation is
individually costly and mechanisms such as reciprocity or conformity are
absent. Moreover, our results indicate that the spread of favoritism
towards similar others highly depends on the network topology and the
associated heterogeneity of the studied population.

* [18] Evolution of ethnocentrism on undirected and directed
Barab√^√¬°si√Ę‚^¬¨‚^ņ^‹Albert networks, F.W.S. Lima, Tarik Hadzibeganovic,
Dietrich Stauffer, 2009/12/15, DOI: 10.1016/j.physa.2009.08.029, Physica
A: Statistical Mechanics and its Applications Volume 388, Issue 24, 15
December 2009, Pages 4999-5004


Effects of multiple gene control on the spread of altruism by group
selection , arXiv

Excerpt: It was suggested recently that chances for altruistic behavior to
spread highly increase when it is controlled not by a single gene but by
multiple independent genes substitutable in their effects on the phenotype
of the individual. Here we confirm the original verbal model published as
part of the frozen plasticity theory by numerical modeling of the spread
of altruistic/selfish alleles in a metapopulation consisting of partly
isolated groups of organisms (demes) interconnected by migration. We have
shown that altruistic behavior coded by multiple substitutable genes can
stably coexist with selfish behavior, even under relatively high mutation
and migration rates, i.e. under such conditions where altruistic behavior
coded by a single gene is quickly outcompeted in a metapopulation.

* [19] Effects of multiple gene control on the spread of altruism by group
selection, T. Kulich, J. Flegr, 2010/02/22, arXiv:1002.4204 [19]

 Barry Wellman

  S.D. Clark Professor of Sociology, FRSC               NetLab Director
  Department of Sociology                  725 Spadina Avenue, Room 388
  University of Toronto   Toronto Canada M5S 2J4   twitter:barrywellman             fax:+1-416-978-3963
  Updating history:

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