  We investigate the effects of local population structure in
reaction-diffusion processes representing a contact process (CP) on
metapopulations represented as complex networks. Considering a model in which
the nodes of a large scale network represent local populations defined in terms
of a homogeneous graph, we show by means of extensive numerical simulations
that the critical properties of the reaction-diffusion system are independent
of the local population structure, even when this one is given by a ordered
linear chain. This independence is confirmed by the perfect matching between
numerical critical exponents and the results from a heterogeneous mean field
theory suited, in principle, to describe situations of local homogeneous
mixing. The analysis of several variations of the reaction-diffusion process
allow to conclude the independence from population structure of the critical
properties of CP-like models on metapopulations, and thus of the universality
of the reaction-diffusion description of this kind of models.
