Evolutionarily stable strategies of migration in heterogeneous environments

By means of a simulation model we are showing that the rates of migration c an be related to avoidance of competition between relatives, especially in clonal organisms. This could result in a strong selective pressure for migr ation, even at a high cost. In addition, if the habitat is fragmented, migr ation can strongly affect local dynamics and result in a dramatic decrease of the densities in some places. In parthenogenetically reproducing organis ms like aphids, the level of relatedness in local populations is expected t o be very high and therefore they can serve as a good model group for testi ng these hypotheses.