Fluctuations and correlations in lattice models for predator-prey interaction.
Including spatial structure and stochastic noise invalidates the classical Lotka-Volterra picture of stable regular population cycles emerging in models for predator-prey interactions. Growth-limiting terms for the prey induce a continuous extinction threshold for the predator population whose critical properties are in the directed percolation universality class. We discuss the robustness of this scenario by considering an ecologically inspired stochastic lattice predator-prey model variant where the predation process includes next-nearest-neighbor interactions. We find that the corresponding stochastic model reproduces the above scenario in dimensions 1< d < or =4, in contrast with the mean-field theory, which predicts a first-order phase transition. However, the mean-field features are recovered upon allowing for nearest-neighbor particle exchange processes, provided these are sufficiently fast.
Mobilia
Mauro
M
Arnold Sommerfeld Center for Theoretical Physics and CeNS, Department of Physics, Ludwig-Maximilians-Universität München, D-80333 Munich, Germany. mauro.mobilia@physik.lmu.de
Georgiev
Ivan T
IT
Täuber
Uwe C
UC
D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D003198:Computer Simulation; D017753:Ecosystem; D020387:Food Chain; D005716:Game Theory; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D011157:Population Dynamics; D011235:Predatory Behavior / Q000502:physiology*; D013223:Statistics as Topic; D013269:Stochastic Processes; D015996:Survival Rate