They are small enough to rest on a fingertip, yet they carry a message from 60,000 years ago. Tiny stone arrow points unearthed at Umhlatuzana Rock Shelter in South Africa’s KwaZulu-Natal province appear to have been coated with poison, according to research published Jan. 7 in Science Advances. Scientists say the discovery is the oldest direct chemical evidence of poisoned weapons identified so far.
The finding pushes back confirmed use of poison weapons by hunter-gatherers by more than 50,000 years. Researchers chemically analyzed 10 arrow tips excavated decades ago at the site and detected traces of slow-acting toxins on five of them. The poisons, likely derived from plants, would have weakened prey and reduced the time and energy required for long hunts.
The toxins were identified as the alkaloids buphandrine and epibuphanisine. While these compounds occur in several southern African plants, researchers believe they most likely originated from Boophone disticha, a bulbous plant known locally as gifbol, or poison bulb, which has a long history of use as an arrow poison.
The discovery suggests prehistoric hunter-gatherers understood the pharmacological properties of plants and deliberately utilized their effects to improve hunting success. Lead author Sven Isaksson, a professor of laboratory archaeology at Stockholm University, said the poisoned arrow tips also reflect advanced planning. Because the toxins would not have acted immediately, hunters had to anticipate delayed effects and understand the principle of cause and effect.
Previously, the oldest undisputed evidence of poisoned weapons was a 7,000-year-old arrow poison found in the thigh bone of a hoofed animal in South Africa’s Kruger Cave. Older finds exist, including a 24,000-year-old wooden object believed to be a poison applicator from Border Cave, South Africa, but those claims remain contested.
Researchers believe the Umhlatuzana hunter-gatherers relied on a simple, single-ingredient poison, with more complex mixtures developing much later. The team plans to study younger layers at the site to determine whether poison-tipped arrows were used continuously or abandoned before being rediscovered.