Evolutionary Implications of Natural Regulation

Many changes in abundance can be attributed to changes in extrinsic factors such as weather, disease or predation. But some changes in abundance are the result of changes in the genetic properties of the organisms in a population. Such evolutionary changes are produced by the genetic feedback mechanism. It is believed by the biologists that natural population regulation has its foundation in the process of evolution.

Illustrate the type of systematic changes by a simple model which could be involved in the genetic feedback mechanism. Consider a two-species system of one plant and one herbivore, and to make the model simple, let us focus on only one gene on one chromosome in the plant. The hypothetical gene has a major effect on

• The ability of the plant to survive in its environment and
• The palatability of the plant to the herbivore. Two different alleles (A and a) occur at the hypothetical gene