Mastodon State Park is the site where the Mastodon above was found in the Kimmswick bone bed; the first evidence that humans and the American Mastodon co existed. The theory is that the area was swampy and the mastodons as well as the giant ground sloth might have gotten stuck in the mud and died.The early American Indians arrive in Missouri about the same time. Early Indians in the background The Clovis culture is document as the earliest Native American Indian that occupied North America and may have contributed to the extinction of many of the Pleistocene animalsGiant ground sloth. Think how this baby would have fed a family for a long time! The museum also has several hiking trails, but the bone beds are no longer active.