Archaeologists have identified traces of two toxic plant alkaloids — buphandrine and epibuphanisine — on artifacts from Umhlatuzana Rock Shelter in KwaZulu-Natal, South Africa. Known as backed microliths, the artifacts were excavated from deposits dated to about 60,000 years ago, placing the use of poisoned weapons deep into the Late Pleistocene.
The 60,000-year-old backed microlith from Umhlatuzana Rock Shelter in KwaZulu-Natal, South Africa: (A) buphanidrine and (B) epibuphanisine detected in a sample from the microlith; (C) the microlith showing the reddish poisonous adhesive residue still adhering to the dorsal backed portion of the tool. Image credit: Isaksson et al., doi: 10.1126/sciadv.adz3281.
“This is the oldest direct evidence that humans used arrow poison,” said University of Johannesburg’s Professor Marlize Lombard.
“It 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.”
Professor Lombard and colleagues analyzed residues on 10 quartz microliths using gas chromatography-mass spectrometry.
They identified two toxic plant alkaloids — buphanidrine and epibuphanisine — on five of them.
These compounds only originate from the plant family Amaryllidaceae indigenous to southern Africa.
The most likely source is a species called Boophone disticha, also associated with historically documented arrow poisons.
The residue patterns indicate that the Umhlatuzana microliths were hafted transversely and used as arrow tips.
On some artifacts, the poison residue was macroscopically visible along the dorsal backed portion, suggesting that toxic compounds were mixed into an adhesive to fix the stone point to the arrow shaft.
Microscopic impact scars and striations on the edges were consistent with its use as a transversely hafted arrow tip.
To confirm their findings, the researchers compared ancient residues with poisons extracted from arrowheads collected in South Africa during the 18th century.
“Finding traces of the same poison on both prehistoric and historical arrowheads was crucial,” said Stockholm University’s Professor Sven Isaksson.
“By carefully studying the chemical structure of the substances, we were able to determine that these particular substances are stable enough to survive this long in the ground.”
The discovery pushes direct evidence for poisoned weapons far deeper into the past.
Before this work, the earliest confirmed poison for arrows dated to the mid-Holocene — several thousand years ago — while Umhlatuzana Rock Shelter clearly documents such technology at least 60,000 years ago.
According to the authors, poisoned arrows were not designed to kill instantly, but instead relied on toxins that weakened animals over time, allowing hunters to track prey over long distances.
“Using arrow poison requires planning, patience and an understanding of cause and effect,” said Linnaeus University’s Professor Anders Högberg.
“It is a clear sign of advanced thinking in early humans.”
The discovery is described in a paper published January 7 in the journal Science Advances.
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Sven Isaksson et al. 2026. Direct evidence for poison use on microlithic arrowheads in Southern Africa at 60,000 years ago. Science Advances 12 (2); doi: 10.1126/sciadv.adz3281
