Robust ecological pattern formation induced by demographic noise.
We demonstrate that demographic noise can induce persistent spatial pattern formation and temporal oscillations in the Levin-Segel predator-prey model for plankton-herbivore population dynamics. Although the model exhibits a Turing instability in mean-field theory, demographic noise greatly enlarges the region of parameter space where pattern formation occurs. To distinguish between patterns generated by fluctuations and those present at the mean-field level in real ecosystems, we calculate the power spectrum in the noise-driven case and predict the presence of fat tails not present in the mean-field case. These results may account for the prevalence of large-scale ecological patterns, beyond that expected from traditional nonstochastic approaches.
Butler
Thomas
T
Department of Physics and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801, USA.
Goldenfeld
Nigel
N
D000818:Animals; D017753:Ecosystem; D005247:Feeding Behavior; D008954:Models, Biological; D010933:Plankton / Q000502:physiology; D011235:Predatory Behavior