The landscape was very different. Although glaciers were retreating, much of the midwest was still under ice. Some areas had been only recently deglaciated and covered with bare sheets of till that were slowly being revegetated. Large lakes formed where morraines dammed water coming off melting glaciers. Lakes, marshes, and bogs were common.

The climate was quite different: summer temperatures were significantly cooler than today. Winter temperatures were colder than today but not dramatically so. Because of the cooler climate, many of the plants and animals were different than those today.

(Illinois State Museum)