THE GREAT BASIN OF North America is a 200,000-square-mile depression that extends from the scorched soil of Death Valley in southern California to the shores of Utah’s Great Salt Lake. Its dry desert valleys are divided by more than 560 long, parallel mountain ranges that reach heights of more than 14,500 feet. The driest region on the continent, the Great Basin is unique in North America because it is a closed watershed—any precipitation or snowmelt that accumulates there flows into lakes rather than into the ocean.
At first glance, the Great Basin might appear inhospitable, but a closer examination reveals a landscape rich with plants and animals that supported foraging communities for millennia. The region has numerous rock shelters and caves that offered people comfortable homes. Large herds of bighorn sheep lived among the basin’s rocky crags and alpine ridges, and plants such as piñon pine and biscuit-root, or desert parsley, provided people with staples they could rely on year after year. Tribes including the Washoe, Western Shoshone, Ute, and Paiute established themselves in the region thousands of years ago and continue to live in the Great Basin today. During periods of stability, their ancestors thrived. But it is an eternal truth that nothing stays the same forever, and when the environment shifted and the water dried up, long-established ways of life needed to change as well.
New research conducted by a multidisciplinary team ledof Natural History has identified a previously unknown megadrought in the Great Basin that lasted from 3,100 to 1,800 years ago. This era, known as the Late Holocene Dry Period, was the most severe drought in North America in the last 6,000 years. It upended life for those who called the Great Basin their home. “By pairing ecology and archaeology, we discovered that there was a huge drought that we had been blind to,” says Thomas. “People living in the Great Basin during this time were forced to rethink how they approached their landscape.” By using a combination of precise environmental reconstructions and specialized dating methods, the team has attained an in-depth look at the ways the megadrought impacted the people of the Great Basin and how they adapted to a world that was changing drastically around them.
