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Paleo-Indian Archaic Woodland Mississippian European Contact

Archaic Environment

Early and Mid-Holocene Environments

The retreat of the Laurentide Ice Sheet at about 10,000 years ago signaled the onset of warmer climate in the Midwest. At this time expansive deciduous forests with new varieties of plants and small mammals replaced those adapted to colder environments. Shallow marshes, streams, and deep backwater lakes covered much of the valley floor. Higher parts of the valley drained and streams became quiet flat-water sloughs and lakes much shallower as climatic onditions became gradually drier starting about 8000 years ago. By about 4000 years ago more moist conditions like today returned after this Mid-Holocene drying, but the valley landscape had achieved much of its modern character.

Over many generations, humans adapted to the changing climate and shifts in the natural environment by changing their culture: hunting and gathering strategies, foods, tools, society, settlement, and ritual.


Paleo-Indian Archaic Woodland Mississippian European Contact