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arXiv · 1204.3398

Emergence of diversity in a model ecosystem

Namiko Mitarai·Joachim Mathiesen·Kim Sneppen
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Abstract

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.

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Namiko Mitarai, Joachim Mathiesen, Kim Sneppen. 2012-07-25. Emergence of diversity in a model ecosystem. https://doi.org/10.1103/physreve.86.011929

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