To explain how new variants originate, de Vries developed a mutation theory that led to a temporary rift between those who accepted Darwinian evolution and biometricians who allied with de Vries.
Afissar n almaɣna wa s id axlakan inmizlayan , de Vries ijja efes n mirda n amutti ewayan s aafuqqi jir addinat wi ardaɣ en fal Darwinian evolution d biometricians ijjanen eɣaf id de Vries.