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arXiv · 0903.1753

Non-neutral theory of biodiversity

Ginestra Bianconi·Luca Ferretti·Silvio Franz
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Abstract

We present a non-neutral stochastic model for the dynamics taking place in a meta-community ecosystems in presence of migration. The model provides a framework for describing the emergence of multiple ecological scenarios and behaves in two extreme limits either as the unified neutral theory of biodiversity or as the Bak-Sneppen model. Interestingly, the model shows a condensation phase transition where one species becomes the dominant one, the diversity in the ecosystems is strongly reduced and the ecosystem is non-stationary. This phase transition extend the principle of competitive exclusion to open ecosystems and might be relevant for the study of the impact of invasive species in native ecologies.

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Ginestra Bianconi, Luca Ferretti, Silvio Franz. 2009-03-10. Non-neutral theory of biodiversity. https://doi.org/10.1209/0295-5075/87/28001

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