Researchers from South Africa and Sweden have found traces of poison on 60,000-year-old arrowheads in South Africa. Their discovery, reported by Stockholm University in the journal Science Advances, is the earliest direct evidence of the use of poisoned hunting weapons in the world so far. The oldest poisoned arrowheads known prior to the present study date to approximately 6,700 years ago.The quartz arrowheads were collected from sediment at Umhlatuzana Rock Shelter in KwaZulu-Natal, South Africa dated to the Pleistocene age. By analyzing the chemical structure of residue on the arrowheads, researchers identified a poison made from gifbol (Boophone disticha), a plant still used by traditional hunters in the region.“[The find] shows that our ancestors in southern Africa not only invented the bow and arrow much earlier than previously thought, but also understood how to use nature’s chemistry to increase hunting efficiency,” says study co-author Marlize Lombard, a researcher at the Palaeo-Research Institute at the University of Johannesburg.Similar poisons have been found arrowheads collected in South Africa in the late 1700s, offering evidence of a continuity of knowledge between prehistoric and historical times. Furthermore, plant poisons like the ones used on these arrowheads were not immediately lethal, meaning that ancient hunters were cognitively quite sophisticated, according to lead researcher Sven Isaksson, a professor of archaeological science at Stockholm University.“It takes a developed working memory to be able to predict that if I put this arrowhead into that plant, it will shorten the delay before I get my hands on this meat,” he told the New York Times.