A Michigan boy exploring a creek finds what looks like a really big , really old tooth . He takes it home and shows his parents who are shocked to see that the tooth is actually an adult human skull! An expert determines it 's a tooth from a long-extinct mastodon . Mastodons were elephant-like beasts that roamed North America 10,000 years ago .
A Michigan boy exploring a creek finds what looks like a really big , really old tooth . The tooth is 8 inches in length , brown , and has six peaks . An expert determines it 's a tooth from a long-extinct mastodon . Mastodons were elephant-like beasts that roamed North America 10,000 years ago .