Sharp thinking: Earlier human ancestor made stone spear tips 500,000 years ago, study says

This undated image provided by Jayne Wilkins shows different angles of an estimated 500,000-year-old stone point from Kathu Pan, South Africa. The scale bar at bottom is 1 centimeter long. In a study published in the journal Science on Thursday, Nov. 15, 2012, scientists say theyve found evidence that stone tips for spears were made much earlier than thought, maybe even created by an earlier ancestor than has been believed. Both Neanderthals and members of our own species Homo sapiens used stone tips - a significant development that made spears more effective, lethal hunting weapons. The new findings from South Africa suggest that maybe they didnt invent that technology, but inherited it from their last shared ancestor, Homo heidelbergensis. (AP Photo/Jayne Wilkins)

This undated image provided by Jayne Wilkins shows different angles of an estimated 500,000-year-old stone point from Kathu Pan, South Africa. The scale bar at bottom is 1 centimeter long. In a study published in the journal Science on Thursday, Nov. 15, 2012, scientists say theyve found evidence that stone tips for spears were made much earlier than thought, maybe even created by an earlier ancestor than has been believed. Both Neanderthals and members of our own species Homo sapiens used stone tips - a significant development that made spears more effective, lethal hunting weapons. The new findings from South Africa suggest that maybe they didnt invent that technology, but inherited it from their last shared ancestor, Homo heidelbergensis. (AP Photo/Jayne Wilkins)