Noise Induced Phenomena in the Dynamics of Two Competing Species

TL;DR

This paper explores how noise influences the dynamics of two competing species, revealing phenomena like oscillations, resonance, and pattern formation, validated through models and real ecosystem data.

Contribution

It introduces new insights into noise-induced effects in ecological competition models and validates these findings with empirical marine and microbial ecosystem data.

Findings

Noise induces quasi-deterministic oscillations

Noise causes stochastic resonance and delayed extinction

Spatial patterns of species are reproduced by models

Abstract

Noise through its interaction with the nonlinearity of the living systems can give rise to counter-intuitive phenomena. In this paper we shortly review noise induced effects in different ecosystems, in which two populations compete for the same resources. We also present new results on spatial patterns of two populations, while modeling real distributions of anchovies and sardines. The transient dynamics of these ecosystems are analyzed through generalized Lotka-Volterra equations in the presence of multiplicative noise, which models the interaction between the species and the environment. We find noise induced phenomena such as quasi-deterministic oscillations, stochastic resonance, noise delayed extinction, and noise induced pattern formation. In addition, our theoretical results are validated with experimental findings. Specifically the results, obtained by a coupled map lattice model, well reproduce the spatial distributions of anchovies and sardines, observed in a marine ecosystem. Moreover, the experimental dynamical behavior of two competing bacterial populations in a meat product and the probability distribution at long times of one of them are well reproduced by a stochastic microbial predictive model.