[saalweachter]

The best way to prepare for future evolutionary challenges is to stockpile genetic diversity. More genetic diversity means both less of a chance of the entire population being vulnerable in the same way to a new threat, and better chances to reach new local maximas that are two or three hops through rough terrain in the evolutionary search space.

Continually applying harsh selection criteria just homogenizes a population to a local maxima and leaves them vulnerable to future change.