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The shape of ecological networks

Michael Lassig·Ugo Bastolla·Susanna C. Manrubia·Angelo Valleriani
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Abstract

We study the statistics of ecosystems with a variable number of co-evolving species. The species interact in two ways: by prey-predator relationships and by direct competition with similar kinds. The interaction coefficients change slowly through successful adaptations and speciations. We treat them as quenched random variables. These interactions determine long-term topological features of the species network, which are found to agree with those of biological systems.

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Michael Lassig, Ugo Bastolla, Susanna C. Manrubia, Angelo Valleriani. 2001-01-16. The shape of ecological networks. https://doi.org/10.1103/physrevlett.86.4418

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