https://doi.org/10.1140/epjb/e2017-80220-7
Regular Article
Extinction phase transitions in a model of ecological and evolutionary dynamics
1 Department of Physics, Missouri University of Science and Technology, Rolla, 65409 Missouri, USA
2 Department of Physics, University of Vermont, Burlington, 05405 Vermont, USA
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e-mail: vojtat@mst.edu
Received: 13 April 2017
Received in final form: 19 May 2017
Published online: 5 July 2017
We study the non-equilibrium phase transition between survival and extinction of spatially extended biological populations using an agent-based model. We especially focus on the effects of global temporal fluctuations of the environmental conditions, i.e., temporal disorder. Using large-scale Monte-Carlo simulations of up to 3 × 107 organisms and 105 generations, we find the extinction transition in time-independent environments to be in the well-known directed percolation universality class. In contrast, temporal disorder leads to a highly unusual extinction transition characterized by logarithmically slow population decay and enormous fluctuations even for large populations. The simulations provide strong evidence for this transition to be of exotic infinite-noise type, as recently predicted by a renormalization group theory. The transition is accompanied by temporal Griffiths phases featuring a power-law dependence of the life time on the population size.
Key words: Statistical and Nonlinear Physics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2017