To the settlers of central Illinois the mammals of the plains played an important role by providing meat for food and hides for shelter and clothing. Some of these animals such as the American Bison (Bison bison) became completely extinct while others, such as the White-tailed Deer (Odocoileus virginianus), have adapted to the changes in their environment and continue to thrive in the area.

When strolling through the historic neighborhood surrounding Abraham Lincoln's home, visitors will often observe Eastern Cottontails (Sylvilagus floridanus), Fox Squirrels (Sciurus niger), and Eastern Chipmunks (Tamias striatus). Occasional sightings have included White-tailed Deer (Odocoileus virginianus) and Virginia Oppossum (Didelphis virginiana). Several species of mice inhabit the park today and become occasional visitors inside the homes. The remains of three mice were found in the kitchen wall of the Lincoln Home during the 1987 restoration project.