Multilevel Particle Systems and the Study of Biological Evolution

#### P. Hogeweg

2005, v.11, Issue 2, 291-312

ABSTRACT

Biotic systems are preeminently multilevel systems in which processes at different space- and time-scales interact. In order to study such processes we use particle based systems in two ways. First we review results in which larger scale spatial patterns formed by local interaction between the model particles feed back, via Darwinian evolution, on the local interactions. The conclusion from this work is that multiple levels of selection occur, and that the basic properties of earlier recognized major transition in evolution'' are generically exhibited in such model systems. Secondly we examine particle' models which are defined as multilevel systems. The particles' here extend over many grid cells, and are flexible in shape. Shape changes take place at the grid-level, however these changes are co-determined by properties of the extended particles. We use this formalism to study two examples of major transitions in evolution in more detail. We demonstrate the power of this formulation for modeling multilevel evolution and development.

Keywords: multilevel particle systems,biomathematical modelling,stochastic processes,spatial self-organization,cellular automata