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Mutation Theory of Evolution by Hugo De Vries

Hugo de Vries (1901) put forward a theory of evolution, called mutation theory. The theory states that evolution is a jerky process where new varieties and species are formed by mutations (discontinuous variations) that function as raw material of evolution. The salient features of mutation theory are: 1. Mutations or discontinuous variations are the raw material of evolution. 2. Mutations appear all of a sudden. They become operational immediately. 3. Unlike Darwin’s continuous variations or fluctuations, mutations do not revolve around the mean or normal character of the species. 4. The same type of mutations can appear in a number of individuals of a species. All mutations are inheritable. 6. Mutations appear in all conceivable directions. 7. Useful mutations are selected by nature. Lethal mutations are eliminated. However, useless and less harmful ones can persist in the progeny. 8. Accumulation of variations produce new species. Sometimes a new species is pro­duced from a single mutation. 9 Evolution is a jerky and discontinuous process.