 It was popular with early geneticists such as Hugo de Vries, who along with Carl Correns helped rediscover Gregor Mendel's laws of inheritance in 1900, William Bateson, a British zoologist who switched to genetics, and early in his career Thomas Hunt Morgan.Some of these geneticists developed it into the mutation theory of evolution.There was also a debate over accounts of the evolution of mimicry and if they could be explained by gradualism or saltation.