Answers

Rohit Malviya
Jul 25, 2020

Hugo de Vries worked on evening primrose and put forth an idea that large differences arise suddenly in population. He believed that it is mutation which causes evolution and not the minor variations that Darwin talked about. Mutations are random and directionless, while Darwinian variations are small and directional.

Evolution was gradual for Darwin, while de Vries believed mutation caused speciation and hence called it saltation (single step large mutation).