Question

Write a short note on the theory of mutations.

Answer 1

Hugo de Vries studied the inheritance of flower colour in evening primrose and proposed mutation theory. The theory says that mutations are sudden, random, and inheritable and discontinuous variations which serve as raw material for evolution. The mutations are irreversible and are passed on to the next generations.

Hudo De Vries conducted his experiments on Oenothera Lamarckian, (Evening Primrose) and found several aberrant types. When O. Lamarckian was self-pollinated and its seeds were allowed to grow, majority of F${}_1$ plants were similar to the parents, but a few were different plants. The different plants were also self-pollinated and when their seeds were sown, the majority of the plants were similar to the parents while a few were still more different plants and this continued generation after generation. These plants appeared to be new species, Hugo de Vries suggested from his experiments that new types of inherited characteristics may appear suddenly without any previous indication of their presence in the race.