What's Here—What's not?
Giant ground sloths, giant beavers, short-faced bears, lions, sabre-tooth cats, mastodonts, mammoths, and stag-moose roamed the Illinois landscape. During warm interglacial periods, giant tortoises moved into the area.
The Great Lakes had not yet formed. Rivers drained the land, but they were not rivers we know today. Modern humans were evolving on other continents, but they didn't arrive in Illinois until the last part of the Pleistocene.
Were All Ice Age Animals Giants?
No. Although some of the now-extinct species were huge, most Ice Age animals
were the same size as today's. In fact, many of the same species are still
present in Illinois or in northern areas with cooler climates.