Cueva de las Manos (Spanish for Cave of the Hands or Cave of Hands) is a cave and complex of rock art sites in the province of Santa Cruz, Argentina, south of the town of Perito Moreno. It is named for the hundreds of paintings of hands stenciled, in multiple collages, on the rock walls. The art was created in several waves between 7,300 BC and 700 AD, during the Archaic period of pre-Columbian South America. The age of the paintings was calculated from the remains of bone pipes used for spraying the paint on the wall of the cave to create the artwork, radiocarbon dating of the artwork, and stratigraphic dating. The site is considered by some scholars to be the best material evidence of early South American hunter-gatherer groups. Argentine surveyor and archaeologist Carlos J. Gradin and his team conducted the most important research on the site in 1964, when they began excavating sites during a 30-year study of cave art in and around Cueva de las Manos. The site is a National Historic Monument in Argentina and a UNESCO World Heritage Site. Location Cueva de las Manos refers to both the main site of the cave and the surrounding complex of rock art sites that includes it. The cave lies at the base of a stepped cliff in the Pinturas River Canyon, in the upper part of the Deseado River basin, in an isolated part of Patagonia. It is about south of Perito Moreno, a town in northwest Santa Cruz Province, Argentina. It is part of both Perito Moreno National Park and Cueva de las Manos Provincial Park. Climate During the time of the Paleoindians, around the late Pleistocene to early Holocene geological periods, the areas between above sea level formed a microclimate in the canyon promoting a grassland ecosystem hospitable to many animals. This ecosystem included the Schinus molle plant, which was used to form resins and adhesives and as a source of firewood. It was also home to edible vegetables and plants that could be used for medicine; tubers, such as the rush root; and numerous fruits, such as that of the Berberis plant. The current climate of the cave area can be described as precordilleran steppe (or "grassy foothills"). The climate is cold and dry, with very low humidity. Ian N. M. Wainwright and colleagues state that the area receives a total annual precipitation