100,000 years ago, North America was much different than it is today. The continent was covered in glaciers, and the climate was much colder. The land was mostly tundra and boreal forest, with some areas of grassland and deciduous forest. The Great Lakes were not yet formed, and the Mississippi River was much smaller. The land was home to a variety of large mammals, including mammoths, mastodons, giant sloths, and saber-toothed cats.
