In the neutral theory of molecular evolution, genetic drift is seen as the most important element causing evolutionary change at the [[DNA]] sequence level: Since most changes at the molecular level are neither good (beneficial) nor bad (deleterious), but neutral, these changes must "drift" to fixation. | In the neutral theory of molecular evolution, genetic drift is seen as the most important element causing evolutionary change at the [[DNA]] sequence level: Since most changes at the molecular level are neither good (beneficial) nor bad (deleterious), but neutral, these changes must "drift" to fixation. |