Selectability of potentially coexisting attractors in a molecular network. Each dot corresponds to a compartment just prior to division. (Top) Due to its autocatalytic properties a viable loop enables a higher growth rate and therefore the network with the large viable loop (characterized by 26 reactions and dividing after approximately 20 000 time steps) constitutes the most frequent network type. Spontaneous reaction rate = 0.00001. Propagule size 800; no selection (S = 1). (Bottom) However, with a mere 1 percent fitness advantage (S = 1.01) attributed to the networks without the loop, it is possible to reduce its frequency. In this case the original network without any viable loops is the most frequent.