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arXiv · 1104.2464

Competition and cooperation in one-dimensional stepping stone models

K. S. Korolev·David R. Nelson
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Abstract

Cooperative mutualism is a major force driving evolution and sustaining ecosystems. Although the importance of spatial degrees of freedom and number fluctuations is well-known, their effects on mutualism are not fully understood. With range expansions of microbes in mind, we show that, even when mutualism confers a distinct selective advantage, it persists only in populations with high density and frequent migrations. When these parameters are reduced, mutualism is generically lost via a directed percolation process, with a phase diagram strongly influenced by an exceptional DP2 transition.

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K. S. Korolev, David R. Nelson. 2011-04-17. Competition and cooperation in one-dimensional stepping stone models. https://doi.org/10.1103/physrevlett.107.088103

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