The biological requirements for an ecosystem to develop and maintain species diversity are in general unknown. Here we consider a model ecosystem of sessile and mutually excluding organisms competing for space [Mathiesen et al. Phys. Rev. Lett. 107, 188101 (2011)]. The competition is controlled by an interaction network with fixed links chosen by a Bernoulli process. New species are introduced in the system at a predefined rate. In the limit of small introduction rates, the system becomes bistable and can undergo a phase transition from a state of low diversity to high diversity. We suggest that patches of isolated meta-populations formed by the collapse of cyclic relations are essential for the transition to the state of high diversity.
@article{arxiv.1204.3398,
title = {Emergence of diversity in a model ecosystem},
author = {Namiko Mitarai and Joachim Mathiesen and Kim Sneppen},
journal= {arXiv preprint arXiv:1204.3398},
year = {2012}
}
Comments
7 pages, 6 figures. Accepted for publication in PRE. Typos corrected, Fig.3A and Fig.6 updated