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arXiv · 1212.1673

Parasites on parasites: coupled fluctuations in stacked contact processes

Steven J. Court·Richard A. Blythe·Rosalind J. Allen
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Abstract

We present a model for host-parasite dynamics which incorporates both vertical and horizontal transmission as well as spatial structure. Our model consists of stacked contact processes (CP), where the dynamics of the host is a simple CP on a lattice while the dynamics of the parasite is a secondary CP which sits on top of the host-occupied sites. In the simplest case, where infection does not incur any cost, we uncover a novel effect: a nonmonotonic dependence of parasite prevalence on host turnover. Inspired by natural examples of hyperparasitism, we extend our model to multiple levels of parasites and identify a transition between the maintenance of a finite and infinite number of levels, which we conjecture is connected to a roughening transition in models of surface-growth.

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Steven J. Court, Richard A. Blythe, Rosalind J. Allen. 2013-11-14. Parasites on parasites: coupled fluctuations in stacked contact processes. https://doi.org/10.1209/0295-5075%2F101%2F50001

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