Which of the following animals is NOT part of Michigan's prehistoric fauna?

The American Bison is not part of Michigan's prehistoric fauna because it is a species that thrived in the region during the more recent periods of human history, specifically after the last Ice Age. They are known to have existed in North America as the last Ice Age glaciers receded, and their presence persisted well into the 19th century.

On the other hand, the giant beaver, mastodon, and saber-toothed tiger were all present in Michigan during prehistoric times. The giant beaver, known for its extensive size, lived in the wetlands and lakes of North America during the Pleistocene era. The mastodon, a relative of modern elephants, roamed the landscape during the same period and is closely associated with the last Ice Age. The saber-toothed tiger, known for its distinctive elongated canine teeth, was also part of the pre-Ice Age megafauna in North America. Collectively, these prehistoric animals depict the diverse ecosystems that existed in Michigan long before the arrival of humans.