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Statistical mechanics of relative species abundance

Kei Tokita
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Abstract

Statistical mechanics of relative species abundance (RSA) patterns in biological networks is presented. The theory is based on multispecies replicator dynamics equivalent to the Lotka-Volterra equation, with diverse interspecies interactions. Various RSA patterns observed in nature are derived from a single parameter related to productivity or maturity of a community. The abundance distribution is formed like a widely observed left-skewed lognormal distribution. It is also found that the ``canonical hypothesis'' is supported in some parameter region where the typical RSA patterns are observed. As the model has a general form, the result can be applied to similar patterns in other complex biological networks, e.g. gene expression.

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Kei Tokita. 2006-07-07. Statistical mechanics of relative species abundance. https://arxiv.org/abs/q-bio/0607011

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