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arXiv · 0807.0122

Instability of spatial patterns and its ambiguous impact on species diversity

Tobias Reichenbach·Erwin Frey
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Abstract

Self-arrangement of individuals into spatial patterns often accompanies and promotes species diversity in ecological systems. Here, we investigate pattern formation arising from cyclic dominance of three species, operating near a bifurcation point. In its vicinity, an Eckhaus instability occurs, leading to convectively unstable "blurred" patterns. At the bifurcation point, stochastic effects dominate and induce counterintuitive effects on diversity: Large patterns, emerging for medium values of individuals' mobility, lead to rapid species extinction, while small patterns (low mobility) promote diversity, and high mobilities render spatial structures irrelevant. We provide a quantitative analysis of these phenomena, employing a complex Ginzburg-Landau equation.

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Tobias Reichenbach, Erwin Frey. 2008-07-01. Instability of spatial patterns and its ambiguous impact on species diversity. https://doi.org/10.1103/physrevlett.101.058102

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