Reproduction age and survival of a Verhulst-free 8-bit Penna population

<div>A Verhulst-free Penna model is shown to be equivalent to a Malthusian model. The population is driven to exponentially increase or decrease with time depending on the value of its minimum reproductive age. This demonstration justifies its identification as a critical parameter. Unlike the Malthusian model however, we are able to obtain a relatively persistent population by imposing a distribution for the critical minimum reproductive age values.</div>