Ancient teeth reveal clues to the environment humans’ early ancestors evolved in millions of years ago

Scientists analyze chemical traces in fossil teeth to uncover ancient diets and ecosystems. Fossilized teeth contain enamel that forms when an animal is young and remains chemically stable for its life, preserving chemical signals from food and water consumed during youth. These signals enable scientists to reconstruct pictures of entire ecosystems, including forests, wetlands, and grasslands that existed millions of years ago.