Effects of intraspecific cooperative interactions in large ecosystems

TL;DR

This paper investigates how intraspecific cooperative interactions, modeled via the Allee effect, influence large ecosystems' dynamics using a generalized Lotka-Volterra framework, revealing significant differences from logistic growth models.

Contribution

It introduces the analysis of the Allee effect in large, multi-species ecosystems within a generalized Lotka-Volterra model, highlighting the impact of functional responses on ecosystem behavior.

Findings

Distinct phase diagram for Allee effect versus logistic growth

Multiple equilibria phase characterized by complex dynamics

Functional response significantly influences ecosystem stability

Abstract

We analyze the role of the Allee effect, a positive correlation between population density and mean individual fitness, for ecological communities formed by a large number of species. Our study is performed using the generalized Lotka-Volterra model with random interactions between species. We obtain the phase diagram and analyze the nature of the multiple equilibria phase. Remarkable differences emerge with respect to the case of the logistic growth case, thus revealing the major role played by the functional response in determining aggregate behaviours of ecosystems.