This mastodon tooth is still attached to a broken piece of jaw bone. Remains of American Mastodon and Woolly Mammoth have been found all over southern Ontario, from Barrie to Sarnia. These findings are often an accidental result of farming activities. Both animals would have roamed the Great Lakes region of southern Ontario during the last Ice Age, following the retreat of the glaciers c. 15,000 to c. 11,700 years ago. These animals can be identified by the shape of their teeth. Mastodons had brachydont teeth, like pigs or humans, with cusped molars. Whereas mammoths had hypsodont teeth, like cows, deer and modern elephants, which would continue to grow throughout the animal’s lifetime.