The structure of human tooth enamel has changed at the nanoscale throughout the course of human history to adapt to changes in our diet, according to international researchers. The team analysed samples of teeth from ancient primates to modern humans, spanning almost 18 million years of evolution. In the past 1.76 million years, the researchers say their samples show an increase in nanocrystal misorientation in the tooth enamel, coinciding with a shift toward more meat and grains in our diets. L