Physiology: Lang and Pa Terson

This theory of mutation would account for differences in the rate of evolution of different organisms, differences in the rate of evolution at different periods in phylogenetic development, the genetic stability of certain genera and species over long periods of time, and the rare occurrence of mutations in most of the existing species of plants and animals. Evolution would depend, to a considerable extent, on the emergent evolution of the gene-duplication and deficiency of gene material in different quantities and in different structural combinations.