Datura quids at Pinwheel Cave, California, provide unambiguous confirmation of the ingestion of hallucinogens at a rock art site.

At a California rock art site called Pinwheel Cave, fibrous quids found in the ceiling alongside a painting possibly depicting Datura flowers were analyzed. Chemical tests detected hallucinogenic alkaloids scopolamine and atropine in the quids, and microscopic analysis identified most as Datura wrightii. Three-dimensional analysis showed the quids were chewed, indicating consumption of the plant in the cave beneath the paintings. Archaeological evidence and dating show the site was used from the Late Prehistoric through Colonial periods for various activities. The findings suggest the rock painting represents the plant and codified communal rituals involving this powerful entheogen, providing the first unambiguous evidence of hallucinogen consumption at a rock art site and challenging prior assumptions about trance and rock art imagery.

Study at a glance

Abstract

While debates have raged over the relationship between trance and rock art, unambiguous evidence of the consumption of hallucinogens has not been reported from any rock art site in the world. A painting possibly representing the flowers of Datura on the ceiling of a Californian rock art site called Pinwheel Cave was discovered alongside fibrous quids in the same ceiling. Even though Native Californians are historically documented to have used Datura to enter trance states, little evidence exists to associate it with rock art. A multianalytical approach to the rock art, the quids, and the archaeological context of this site was undertaken. Liquid chromatography-mass spectrometry (LC-MS) results found hallucinogenic alkaloids scopolamine and atropine in the quids, while scanning electron microscope analysis confirms most to be Datura wrightii Three-dimensional (3D) analyses of the quids indicate the quids were likely masticated and thus consumed in the cave under the paintings. Archaeological evidence and chronological dating shows the site was well utilized as a temporary residence for a range of activities from Late Prehistory through Colonial Periods. This indicates that Datura was ingested in the cave and that the rock painting represents the plant itself, serving to codify communal rituals involving this powerful entheogen. These results confirm the use of hallucinogens at a rock art site while calling into question previous assumptions concerning trance and rock art imagery.