EVOLUTION BY LUCK. “Goldschmidt proposed that a novel phenotype (such as insect wings, a character associated with higher level taxonomy) must first arise as an instantaneous product of a single “macromutation” or “systemic mutation”. Individuals bearing such macromutations were characterized as “hopeful monsters” by Goldschmidt to emphasize that their appearance is neither purposeful nor gradual, and their prospects for success are a matter of luck.”
http://link.springer.com/article/10.1007/s11692-012-9209-0