Tribology involves the science of friction and wear, and MAE Prof. Greg Sawyer has tackled problems ranging from space materials to contact lenses. In a recent Science paper (Erickson et al., 338, p.98, 2012), Sawyer and his colleagues used a combination of wear and hardness measurements on fossilized teeth to create three-dimensional tribological wear models, which reveal how the hadrosaurid’s unique six-tissue dental structure evolved for grinding and ecological specialization.