Humans have used bows and arrows for hunting for thousands of years, as shown in this cave painting from the La Saltadora rock shelter in Spain. Credit: Album/Alamy
Traces of toxic plant compounds have been found on a handful of 60,000-year-old African arrowheads, providing the oldest chemical evidence that Paleolithic hunter-gatherers used poison to bring down prey.
The result, published on January 7 at Advancement of science1It adds to the growing picture of how smart and technologically advanced people are in this era. Making poison darts is as difficult as following a “complicated cooking recipe,” says study co-author Marlyse Lombard, an archaeologist at the University of Johannesburg in South Africa. “You have to add to it the danger of the poison, and plan to work with it without poisoning yourself, then you have to hunt and track the prey animal in difficult and sometimes dangerous conditions for a day or two.”
Early humans in Europe hunted with bows and arrows
Archaeologist Justin Bradfield, also at the University of Johannesburg, who was not involved in the study, agrees: “It shows advanced planning, strategy and causal thinking – something that is very difficult to prove for people who lived a long time ago, but for which the evidence grows every year.”
Archaeologists have already suggested that early modern humans may have begun using poisons for hunting about 70,000 to 60,000 years ago, around the same time that projectile weapons such as bows and arrows were invented. Many of the sharp stones found in this time period are too small to cause lethal damage to prey on their own without the addition of poison.
However, direct chemical evidence for the presence of toxins has been scant, in part because many toxic chemicals break down over time. “The conditions would have to be quite extraordinary to maintain the integrity of any organic molecules for such a long period,” says Bradfield.
Poisonous bulb
Sven Isaksson, a biomolecular archaeologist at Stockholm University, and his colleagues examined a group of ten microliths—sharp stone flakes about a centimeter wide—found at the Umhlatuzana rockshelter in KwaZulu-Natal, South Africa. Chemical analysis revealed traces of a toxic compound called bubandrin on five of them.
Bubandren is found in a local plant called Boophone clips Sometimes known as com. gifbol or Poison bulb. A small amount of substances derived from the milky secretions of the root bulb of this plant can kill mice in half an hour; In humans the toxin can cause nausea, respiratory paralysis and lead to coma.
Poison bulb plant Boophone clips.Credit: Ariadne van Zandbergen/Alamy
The team also found bubandrin on a set of four arrowheads collected by an ethnographer in South Africa in the 18th century. Today, indigenous people sometimes hunt springbok, kudu, wildebeest, and even zebra and giraffes using similar small poisoned arrows, Lombard says. “There is no reason to believe that Umhlatozana hunters did not do the same.”
It’s possible there were originally other toxins in the mix, such as snake or spider venoms, which have long since decomposed, Isaacson says. Isaacson says his previous work studies 1,000-year-old arrowheads2 Help narrow down the types of plant compounds that may survive for thousands of years.