Did you know that tusks are enormous teeth? Many animals have them, but the biggest ones belong to elephants and their relatives, including mastodons. Mastodons are now extinct, but paleontologists can use fossil tusks to study the lives of these ancient giants. For our study, we analyzed the right tusk of a male mastodon found in 1998. We also analyzed two chemical elements preserved in the tusks: oxygen and strontium. Using different forms of these elements (called isotopes), we tracked the season when a particular layer of tusk was grown, as well as where he grew it. We learned that he traveled long distances to mate with females. He also had fights with other mastodons and even died during his final battle!