Zoology - Evolution Question with Solution | TestHub

Hugo de Vries based on his work on evening primrose brought forth the idea of mutations - large difference arising suddenly in a population. He believed that it is a mutation that causes evolution and not the minor variations (heritable) that Darwin talked about. Mutations are random and directionless while Darwinian variations are small and directional. Hugo deVries believed saltation (single-step large mutation) caused the formation of species. Saltation is a single step large mutation.