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\newblock Coevolution of hosts and parasites.
\newblock {\em Parasitology}, 85:411--426, 1982.

\bibitem[\protect\citeauthoryear{Baveco and Lingeman}{1992}]{Baveco:1992}
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\newblock An object-oriented tool for individual-oriented simulation:
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\newblock {\em Ecological Modelling}, 61:267--286, 1992.

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\newblock {\em Ecology}.
\newblock Blackwell Scientific Publications, Oxford, UK, 1990.

\bibitem[\protect\citeauthoryear{Boerlijst and Hogeweg}{1992}]{Boerlijst:1992}
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\newblock Self-structuring and selection: Spiral waves as a substrate for
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\newblock In Christopher G.~Langton et~al., editor, {\em Artificial Life II},
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\bibitem[\protect\citeauthoryear{Caswell and John}{1992}]{Caswell:1992}
Hal Caswell and A.~M. John.
\newblock From the individual to the population in demographic models.
\newblock In D.~DeAngelis and L.~Gross, editors, {\em Individual-Based Models
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\bibitem[\protect\citeauthoryear{Caswell}{1989}]{Caswell:1989}
Hal Caswell.
\newblock {\em Matrix Population Models: Construction, Analysis, and
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\newblock Sinauer Associates, Sunderland, MA, 1989.

\bibitem[\protect\citeauthoryear{Collins and Jefferson}{1992}]{Collins:1992}
Robert~J. Collins and David~R. Jefferson.
\newblock The evolution of sexual selection and female choice.
\newblock In F.~J. Varela and P.~Bourgine, editors, {\em Toward a Practice of
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\bibitem[\protect\citeauthoryear{Dewdney}{1989}]{Dewdney:1989}
A.~K. Dewdney.
\newblock Simulated evolution: Wherein bugs learn to hunt bacteria.
\newblock {\em Scientific American}, pages 138--141, May 1989.

\bibitem[\protect\citeauthoryear{Ewald}{1983}]{Ewald:1983}
Paul~W. Ewald.
\newblock Host-parasite relations, vectors, and the evolution of disease
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\newblock {\em Annual Reviews of Ecological Systems}, 14:465--485, 1983.

\bibitem[\protect\citeauthoryear{Ewald}{1993}]{Ewald:1993}
Paul~W. Ewald.
\newblock The evolution of virulence.
\newblock {\em Scientific American}, 268:56--62, April 1993.

\bibitem[\protect\citeauthoryear{Fontana}{1992}]{Fontana:1992}
Walter Fontana.
\newblock Algorithmic chemistry.
\newblock In Christopher G.~Langton et~al., editor, {\em Artificial Life II},
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\bibitem[\protect\citeauthoryear{Hamilton \bgroup \em et al.\egroup
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William~D. Hamilton, R.~Axelrod, and R.~Tanese.
\newblock Sexual reproduction as an adaptation to resist parasites (a review).
\newblock {\em Proceedings of the National Acadamy of Science, USA},
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\bibitem[\protect\citeauthoryear{Hamilton}{1992}]{Hamilton:1992}
William~D. Hamilton, 1992.
\newblock Personal communication. Zoology Dept., South Park Rd., Oxford, OX1
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\bibitem[\protect\citeauthoryear{Herre}{1993}]{Herre:1993}
Edward~Allen Herre.
\newblock Population structure and the evolution of virulence in nematode
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\newblock {\em Science}, 259:1442--1445, March 5 1993.

\bibitem[\protect\citeauthoryear{Hurst}{1991}]{Hurst:1991}
Laurence~D. Hurst.
\newblock The incidences and evolution of cytoplasmic male killers.
\newblock {\em Proceedings of the Royal Society of London B}, 244:91--99, 1991.

\bibitem[\protect\citeauthoryear{Huston \bgroup \em et al.\egroup
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M.~Huston, D.~DeAngelis, and W.~Post.
\newblock New computer models unify ecological theory.
\newblock {\em Bioscience}, 38(10):682--691, 1988.

\bibitem[\protect\citeauthoryear{Koza}{1992}]{Koza:1992}
John~R. Koza.
\newblock Genetic evolution and co-evolution of computer programs.
\newblock In Christopher G.~Langton et~al., editor, {\em Artificial Life II},
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\bibitem[\protect\citeauthoryear{Koza}{1994}]{Koza:1994}
John~R. Koza.
\newblock Artificial life: Spontaneous emergence of self-replicating and
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\newblock In Christopher~G. Langton, editor, {\em Artificial Life III}, pages
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\bibitem[\protect\citeauthoryear{Langton}{1992}]{Langton:1992}
Christopher~G. Langton.
\newblock Life at the edge of chaos.
\newblock In Christopher G.~Langton et~al., editor, {\em Artificial Life II},
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\bibitem[\protect\citeauthoryear{Lindgren and Nordahl}{1994}]{Lindgren:1994}
K.~Lindgren and M.~G. Nordahl.
\newblock Artificial food webs.
\newblock In Christopher~G. Langton, editor, {\em Artificial Life III}, pages
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\bibitem[\protect\citeauthoryear{Maley and Caswell}{1993}]{Maley:1993}
Carlo~C. Maley and Hal Caswell.
\newblock Implementing i-state configuration models for population dynamics: An
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\newblock {\em Ecological Modelling}, 68:75--89, 1993.

\bibitem[\protect\citeauthoryear{May and Anderson}{1990}]{May:1990}
R.~M. May and R.~M. Anderson.
\newblock Parasite-host coevolution.
\newblock {\em Parasitology}, 100:S89--S101, 1990.

\bibitem[\protect\citeauthoryear{May}{1973}]{May:1973}
R.~M. May.
\newblock {\em Model Ecosystems}.
\newblock Princeton University Press, Princeton, NJ, 1973.

\bibitem[\protect\citeauthoryear{Nicholson and Bailey}{1935}]{Nicholson:1935}
A.~J. Nicholson and V.~A. Bailey.
\newblock The balance of animal populations. part i.
\newblock {\em Proceedings of the Zoological Society of London}, 3:551--598,
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\newblock Referenced in Baveco and Lingeman, 1992.

\bibitem[\protect\citeauthoryear{Nowak}{1991}]{Nowak:1991}
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\newblock The evolution of viruses. competition between horizontal and vertical
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\newblock {\em Journal of Theoretical Biology}, 150:339--347, 1991.

\bibitem[\protect\citeauthoryear{Reynolds}{1987}]{Reynolds:1987}
C.~W. Reynolds.
\newblock Flocks, herds, and schools: A distributed behavioral model.
\newblock {\em Computer Graphics}, 21(4):25--34, 1987.

\bibitem[\protect\citeauthoryear{Rizki and Conrad}{1986}]{Rizki:1986}
M.~M. Rizki and M.~Conrad.
\newblock Computing the theory of evolution.
\newblock {\em Physica D}, 22:83--99, 1986.

\bibitem[\protect\citeauthoryear{Taylor \bgroup \em et al.\egroup
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C.~E. Taylor, D.~R. Jefferson, S.~R. Turner, and S.~R. Goldman.
\newblock Ram: Artificial life for the exploration of complex biological
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\newblock In Christopher~G. Langton, editor, {\em Artificial Life}, pages
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\bibitem[\protect\citeauthoryear{Travers}{1989}]{Travers:1989}
M.~Travers.
\newblock Animal construction kits.
\newblock In Christopher~G. Langton, editor, {\em Artificial Life}, pages
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\bibitem[\protect\citeauthoryear{Williams and Nesse}{1991}]{Williams:1991}
George~C. Williams and Randolph~M. Nesse.
\newblock The dawn of darwinian medicine.
\newblock {\em The Quarterly Review of Biology}, 66(1):1--22, 1991.

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