Figure 2. The modules of the control structures shown in Figure 1 are arranged sequentially in arbitrary order; this order is part of the genome however and is kept from generation to generation. Chromosomal crossover is simulated by combining these arrays. In this case, the genome is read by starting at the beginning of the chromosome of the first organism. After the yellow module, the reading frame is shifted to the other chromosome by a pseudorandom trigger. The resulting chromosome is shown in Figure 3.