Fossil dental-wear evidence has revived a dispute over why grazing mammals on the Great Plains evolved such abrasion-resistant teeth: the traditional account credits grass itself, while a competing hypothesis points to windblown grit and dust instead.
What would resolve this Comparative dental microwear and phytolith analysis distinguishing tooth wear caused by grass silica from wear caused by ingested mineral grit.
OpenPaleontologyGreat Plains (Wikipedia)