Bhat, D., J. Pinero, and S. Redner

We investigate the dynamics of the voter model in which the population itself changes endogenously via the birth-death process. There are two species of voters, labeled A and B, and the population of each species can grow or shrink by the birth-death process at equal rates b. Individuals of opposite species also undergo voter model dynamics in which an AB pair can equiprobably become AA or BB with rate v—neutral evolution. In the limit b/v → ∞, the distribution of consensus times varies as t−3 and the probability that the population size equals n at the moment of consensus varies as n−3. As the birth/death rate b is increased, fixation occurs more more quickly; that is, population fluctuations promote consensus.