### ch05p149 enzymes for eating tubers helped human brains expand > Although it's often been argued that the advent of regular meat-eating provided the energy needed for our ancestors to evolve bigger brains, some researchers have recently suggested that plant foods -- and in particular, starchy plant foods, like tubers -- have been rather overlooked. Two key developments -- one cultural, and one genetic -- would have been hugely helped to unlock the energy bound up in starch. The cultural development was cooking; the genetic one was the multipication of a gene that produces an enzyme in saliva to break down starch. Salivary amylase works better on cooked starch than raw starch. - [[Tamed by Alice Roberts#ch05p149 enzymes for eating tubers helped human brains expand|View in Vault]]