The Paisley Caves complex is a system of four caves in an arid, desolate region of south-central Oregon, United States. One of the caves may contain archaeological of the oldest definitively-dated human presence in North. The site was first studied by archeologists in the 1930s. Scientific excavations since 2002 have uncovered substantial new discoveries.
A field school from the University of Oregon has been examining the site since 2002 and analyzing its pre-Clovis artifacts. In the summer of 2007, they identified the oldest human DNA yet discovered in the American continents. This assertion is based on several samples of coprolite (fossilized excrement) found in the Paisley Caves complex, between Lakeview and Bend, Oregon, on the eastern side of the Cascade mountain range.Since then, other authors have questioned the authenticity of these findings by arguing about the relevance of the evidence gathered from ancient DNA and stratigraphy on the one hand, and from the morphological assignment of the coprolites to humans on the other.
The fossils were found in Paisley Five Mile Point Cave at the same level as a small rock-lined hearth some 7 feet (2 m) below the modern surface. At that level was also discovered a large number of bones from waterfowl, fish, and large mammals including extinct camel and horse. Radiocarbon dating places these coprolites between 12,750 and 14,290 calendar years before the present, probably representing a pre-Clovis occupation. DNA analysis provides apparent genetic ties to Siberia or Asia.
Evidence at other archaeological sites — as well as 1930s work at Paisley Caves — had also been thought to provide such evidence, but questionable excavation techniques clouded the issue. Knowing this, the U of O team worked carefully to avoid the mistakes of the past. The theory that pre-Clovis immigrants traveled to North America down the Pacific Coast suggests that the travelers would have passed through the hinterlands of what is Oregon today. The Paisley Caves, up-river from the Pacific Ocean along the Klamath River, are therefore an ideal spot to search for the evidence of such people. The fossils provide evidence of the groups possibly having lived there. DNA from coyote, fox, and dog (or wolf) were also found.