Archaeological records show us that humans apparently came to live here during the Altithermal
period, from 5,500 to 3,000 B.
Fossil bison and artifacts from an early altithermal
period arroyo trap in Wyoming.
This may refer to the severe Altithermal
drought of 7500-8000 B.
The site is near Lake Huron and likely experienced a lowered ground water table until about 6,000 years ago at the end of the dry Altithermal period, when lake and ground water levels were lower throughout the Midwest.
Desiccation and fracturing were probably heightened in the Till Plains of Ohio during the dry Altithermal period (about 6,000 to 9,000 years ago) when prairies and grasslands of the Plains expanded eastward to central Ohio.
timberline advance in western United States.
archeology and paleoecology at Mustang Springs, on the Southern High Plains of Texas.
During the middle Holocene of 7000-5000 years ago, referred to as the Altithermal
, temperatures were considerably warmer than today, paralleling climate now seen in the southeastern Atlantic States.
Apparently there was no warm-moist or dry Altithermal
interval in central Texas but rather a pronounced period of drier and possibly warmer conditions starting about 2000 years ago (Holloway et al.
1988) proposed that this climatic event was the Altithermal
as originally defined by Antevs (1955).