After the problems with the sensory system were fixed, completely different results were obtained. The sensory system remained intact indefinitely, while many features of the overall algorithm changed through evolution.
Evolution has caused changes in the relative and absolute sizes of the two tissues (reproductive and sensory). While the undifferentiated reproductive-cell-only organisms tended to increase the size of their reproductive tissue to our imposed limit of 256 cells, the differentiated organisms have maintained a delicate balance between the sizes of the two tissues which have remained small (both in the 4-32 cell range).
On several occasions, one or more genes have been duplicated, with both copies of the gene being expressed. One copy is expressed by the reproductive tissue, and one copy is expressed by the sensory tissue. While the two copies are initially identical, gradually, the two copies diverge in their structure and function.
This is significant, because biologists believe that gene duplication, followed by divergence of the two copies, is a key feature of the evolution of complex genomes, and particularly of differentiated multi-cellularity.
Evolution also led to a wide variety of decision making algorithms used by the sensory system to select the node to migrate to or to send daughters to. Evolution of the differentiated multi-threaded organisms is explored further by .