Paisley Caves

Archeological Excavations Change Timberline of Earliest Human Occupation of North America

By Steve Lent, Crook County Historian

Paisley Caves are located along the old wave-cut terraces of ancient Lake Chewaucan near Paisley, Oregon in Oregon’s Great Basin. During past ice ages the basin was occupied by a huge inland lake with the only remnant now being Summer Lake. Multiple wildlife and plants were living along the shores and waterways.

The caves were first archaeologically excavated in 1938-39 by renowned University of Oregon archaeologist Luther S. Cressman. His findings determined that early human occupants had inhabited their environment at the same time as extinct Pleistocene species such as camel and mastodons. The manner of excavations and scientific archaeological tools available at the time were limited and proved inconclusive as of dates of occupation.

The caves were further excavated by Dr. Dennis Jenkins of the University of Oregon beginning in 2002. State-of-the-art stratigraphic excavation techniques and advanced laboratory analysis was utilized by Dr. Jenkins and a team of archeology students and researchers. Their focus was on spatially locating every item within the caves relative to the comprehension of events that marked the passage of time at the site. Discoveries included obsidian and bone tool fragments, cut animal bones, sage cordage and evidence of hearths intermingled with Pleistocene animal bones. Advanced methods of radio carbon dating allowed the team to link items to precise moments in time.

Researchers identified and collected numerous desiccated human feces that are called corpolites. DNA analysis determined that the human milchondrial DNA was identical to that of the peoples known to have first emigrated from Asia to the Americas. Analyses of the corpolites demonstrated that diets consisted of grasses, sage grouse and extinct giant bison. Multiple radio carbon dates were calibrated to over 14,000 years before the present predating the earliest Clovis sites (which were believed to be the oldest habitation of North America) by over a thousand years. Discoveries at the excavation site changed the time-line for human occupation of North America.

There was some controversy among archaeologists as to the validity of the corpolite analysis. However further fieldwork under Jenkins supervision strengthened the case. Researchers found a spectacular serrated bone tool that reaffirmed the pre-Clovis origins. The Western Stemmed Tradition tool groupings is much different that the Clovis technology and predated that technology.

Eventually it became accepted by many archaeologists that the Paisley Caves represented some of the earliest human occupation in North America. The Paisley Caves were added to the National Register of Historic Places in 2014.