The average repair rate of the system drops as cells irreversibly accumulate mutations.

<p>Since cells with a low rate of repair are more likely to go apoptotic, a temporary steady state exists where the repair rate of the system fluctuates around an average value of The length of time, before the system leaves this temporary state increases drastically with the size <i>N</i> of the system. If is large, a high rate of repair may be maintained without renewal from the stem cell pool, and consequently the organism ages more slowly. The simulation is carried out with parameters The median of 20 simulation runs is showed.</p>