In many preliminary runs, the metazoans were pulled towards a quite uninteresting mechanism to generate cellular diversity. Non-adhering cells with very long cycles were developed. During development more and more cells disattached from the ``embryo''. Dependent on the phase of their cycle at which they disattached many different cell types were produced. Even more cell types were generated by a mechanism in which the cells ``tickled'' eachother during a few time step, in this way ``pushing'' them out of their cycle.
In order to prevent this behaviour a penalty was given to cells that didn't touch any other cell. Every time step a cell was ``lonely'', the the cell's target size was decreased by one site with a probabiliy that was dependent on the size of the cells. Large cells shrunk faster than small cells.