Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Parasites on parasites: coupled fluctuations in stacked contact
  processes   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.

32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph