As soon as you put starch in your mouth — whether in the form of a dumpling, a forkful of mashed potatoes or a saltine — you start breaking it down with an enzyme in your saliva. That enzyme, known as amylase, was critically important for the evolution of our species as we adapted to a changing food supply. Two new studies revealed that our ancestors began carrying more amylase genes in two major waves: the first one several hundred thousand years ago, possibly as a result of humans starting to cook with fire, and the second after the agricultural revolution 12,000 years ago.
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