This 08 October, 2006 picture shows a skull discovered by a French-Peruvian archaeological team of the University of Paris IV, Sorbonne, working in a cavern in Chaquil, Chachapoyas, more than 1000 kms northeast of Lima. The team of archaeologists discovered at least three human skulls inside the cavern, which would be a proof of human sacrifice practices during the Chachapoyas culture, 800-1470 (AD). Photo credit: HO/AFP/Getty Images