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Evolutionary ecology in-silico:evolving foodwebs, migrating population and speciation

Dietrich Stauffer·Ambarish Kunwar·Debashish Chowdhury
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Abstract

We have generalized our ``unified'' model of evolutionary ecology by taking into account the possible movements of the organisms from one ``patch'' to another within the same eco-system. We model the spatial extension of the eco-system (i.e., the geography) by a square lattice where each site corresponds to a distinct ``patch''. A self-organizing hierarchical food web describes the prey-predator relations in the eco-system. The same species at different patches have identical food habits but differ from each other in their reproductive characteristic features. By carrying out computer simulations up to $10^9$ time steps, we found that, depending on the values of the set of parameters, the distribution of the lifetimes of the species can be either exponential or a combination of power laws. Some of the other features of our ``unified'' model turn out to be robust against migration of the organisms.

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Dietrich Stauffer, Ambarish Kunwar, Debashish Chowdhury. 2004-03-27. Evolutionary ecology in-silico:evolving foodwebs, migrating population and speciation. https://doi.org/10.1016/j.physa.2004.12.036

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