A simulation model of a population having internal (genetic) structure is presented. The population is subject to selection pressure coming from the environment which is the same in the whole system but changes in time. Reproduction has a sexual character with recombination and mutation. Two...

Using a Monte Carlo approach we study a simple lattice model of populations living in a habitat where the external conditions are changing in space and in time. We show that above a certain value of the climatic gradient, the population gathers at a restricted part of the lattice. The average...

The influence of habitat destruction on a population of predators and prey is studied. We show, via Monte Carlo simulations of a lattice model, that with growing devastation the oscillations in the densities of both species, as well as cross-correlations between the two densities diminish. As...