The CA is controlled by the following buttons:

Hide CA-1 Hide CA-2
Start:  CA are planted.
Output rate +: raise the rate
Output rate - : reduce the rate
Information:
Output rate,  resources, Illness indicator, Illness time: or duration.

This applet illustrates what  drives  aging. Let’s summarize first the characteristics of the present system:

1. Resource maximization  which is achieved by the cooperation of the two CA .
2. When the system loses resources it is Ill, and when replenishing them, it is healthy.

The outline of the system is depicted in the image below. Input, is proportional to CA size. On one hand input contributes to  structure, while on the other, structure determines how many resources are taken up. An elephant eats more than a mouse. The two CA  exchange and incorporate resources only when they meet, otherwise they lose resources. In other words input operates only when they cooperate.   Output is the independent driver of the system.  It withdraws from CA-1 one unit/step, and  the observer controls the CA-2 output.

When the applet is loaded two zygotes are planted. Since the  CA lack resources, they are regarded as ill. In the following experiments always set first the desired rate and then click on start. Illness time is the time it takes for the system to replenish its resources.  As you raise the  CA-2 output rate, the system will need more and more time to refill its resources: Above rate = 8 it will fail. When you observe  its response at rate = 6 you will notice that at times the system will refill completely, yet will not be  able to keep the resources since the two CA fly apart.  Cooperation is a prerequisite for system health.  If you want to make the system healthy, turn down the output rate.

Use it or lose it.

The aging organism needs more and more time to replenish its resources. This is why it takes for the elderly  longer  to recover from disease. The main reason for this is a continuous depletion of tissues and organs  due to disuse. The organism loses structure, which affects its input in the same way as illustrated by the applet. Nevertheless  it  is possible to slow down aging either   by lowering output, or by boosting input.  Output is the energy utilized by the organism. It can be lowered by putting the  elderly patient to bed which lets him to recover faster.  However this approach is recommended only during emergency, since it promotes tissue  depletion. Boosting input should be preferred. Since input is proportional to structure, it may be raised by boosting structure with exercise and other means which are discussed in the chapter on How to slow down aging.