Until recently, I did not fully appreciate fossil teeth. Their significance for identifying species and narrowing down the general diet of extinct animals was obvious, but I didn’t understand that teeth also hold intricate records of an individual animal’s life. Tiny pits and scratches on enamel can reveal what a creature was eating around the time it died; oxygen isotopes preserved inside teeth can be used to make inferences about climate, body temperature, and habitat; and the way teeth respond to stress and strain can allow paleontologists to identify the feeding habits of long-dead species.

Prehistoric teeth can also be confusing.