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arXiv · 2112.05098

Intraspecific predator interference promotes biodiversity in ecosystems

Ju Kang·Shijie Zhang·Yiyuan Niu·Fan Zhong·Xin Wang
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Abstract

Explaining biodiversity is a fundamental issue in ecology. A long-standing puzzle lies in the paradox of the plankton: many species of plankton feeding on a limited variety of resources coexist, apparently flouting the competitive exclusion principle (CEP), which holds that the number of predator (consumer) species cannot exceed that of the resources at a steady state. Here, we present a mechanistic model and demonstrate that intraspecific interference among the consumers enables a plethora of consumer species to coexist at constant population densities with only one or a handful of resource species. This facilitated biodiversity is resistant to stochasticity, either with the stochastic simulation algorithm or individual-based modeling. Our model naturally explains the classical experiments that invalidate the CEP, quantitatively illustrates the universal S-shaped pattern of the rank-abundance curves across a wide range of ecological communities, and can be broadly used to resolve the mystery of biodiversity in many natural ecosystems.

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Ju Kang, Shijie Zhang, Yiyuan Niu, Fan Zhong, Xin Wang. 2021-12-09. Intraspecific predator interference promotes biodiversity in ecosystems. https://doi.org/10.7554/elife.93115.2

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