Archeologists from the Hebrew University of Jerusalem and several institutes abroad have discovered stone tools in South Africa that are the "oldest" evidence that ancient cave dwellers existed about two million years ago, it was announced on Tuesday. Prof. Hagai Ron and Dr. Ari Matmon from the Hebrew University's earth sciences institute, along with Dr. Liora Kolska Horwitz and the Israel Geological Institute's Dr. Naomi Porat, were part of an international team at the Wonderwerk caves and worked with other researchers and archeologists from South Africa and Canada. There have been digs at the site since the 1940s, but the renewed digs were in the lower level, where they recently found small stone tools of the Oldowan society dated to two millennia ago. Horwitz said the scene made it clear that the cave-dwellers had worked there and that the tools had not just reached the cave via a flood or collapse. This is the first evidence that people lived in caves so early in human history. Ron and Matmon used advanced methods at their university labs to date 50 soil samples at the cave level where the tools were found. They confirmed the results as being highly accurate using known magnetic field data. The most likely human species to live in the caves were the homo habilis, ("handy man" or "skillful person"), who lived from about 2.5 million to 1.6 million years ago at the beginning of the Pleistocene era. Famous archeologists Mary and Louis Leakey first defined the species after finding fossils in Tanzania in the early 1960s.