Researchers have identified traces of plant toxins on Stone Age arrowheads – making it the oldest known arrow poison in the world to date.
A team analysing 60,000–year–old quartz arrowheads from Umhlatuzana Rock Shelter in KwaZulu–Natal, South Africa, found chemical residues of poison that still have ‘active components’.
This toxic substance is from a plant called gifbol (Boophone disticha), a poisonous species still used by traditional hunters in the region today.
The discovery pushes back the earliest direct evidence of poison arrow use by tens of thousands of years.
In humans the poison can induce symptoms of nausea, visual impairment, respiratory paralysis and a coma.
Even in small quantities, it can be lethal to rodents in just 20 minutes – leading the researchers to believe it was used to slow prey animals down while they hunted them.
‘The compounds we have detected…are active components and they are poisonous,’ Professor Sven Isaksson, from Stockholm University, told the Daily Mail.
‘However, they are today only present as minute traces on these Stone Age artifacts in way too low concentrations to be deadly.’
Both sides of one of the arrowheads analysed. The left–hand image shows the organic remains in which the poisonous arrowhead residues were identified, appearing as a reddish colour
Analysis of the arrowheads, which bear microscopic impact scars (highlighted by the white arrows)
The toxic substance is from a plant called gifbol (Boophone disticha), a poisonous species still used by traditional hunters in the region today (file image)
‘This is the oldest direct evidence that humans used arrow poison,’ Professor Marlize Lombard, from the University of Johannesburg, said.
‘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.’
The researchers said similar poisonous substances have also been found on 250–year–old arrowheads in Swedish collections, which were gathered by travellers during the 18th century.
The fact that the same plant poison was used in both historical and prehistoric times indicates a long continuity of knowledge and tradition, they explained.
‘Finding traces of the same poison on both prehistoric and historical arrowheads was crucial,’ says Professor Sven Isaksson, from Stockholm University.
‘By carefully studying the chemical structure of the substances and thus drawing conclusions about their properties, we were able to determine that these particular substances are stable enough to survive this long in the ground.
‘It’s also fascinating that people had such a deep and long–standing understanding of the use of plants.’
Previously, indirect traces of poison have been used to interpret hunting practices, but the new findings constitute the first direct evidence of hunting with poisoned arrows.
A close–up of the arrowheads unearthed from the from Umhlatuzana Rock Shelter in KwaZulu–Natal, South Africa
A previous study revealed teardrop–shaped tools (pictured) were hurled through the air as weapons 77,000 years ago in South Africa
The study shows that these early hunters not only had technical skills but also advanced planning abilities and an understanding of how poisons work over time – characteristics that reflect modern human cognition.
‘Using arrow poison requires planning, patience and an understanding of cause and effect. It is a clear sign of advanced thinking in early humans,’ Professor Anders Högberg, from Linnaeus University, said.
Before now, the earliest poisoned arrows from Africa date back roughly 7,000 years.
The researchers published their findings in the journal Science Advances.
WHAT DO WE KNOW ABOUT THE HISTORY OF THE STONE AGE?
The Stone Age is a period in human prehistory distinguished by the original development of stone tools that covers more than 95 per cent of human technological prehistory.
It begins with the earliest known use of stone tools by hominins, ancient ancestors to humans, during the Old Stone Age – beginning around 3.3million years ago.
Between roughly 400,000 and 200,000 years ago, the pace of innovation in stone technology began to accelerate very slightly, a period known as the Middle Stone Age.
By the beginning of this time, handaxes were made with exquisite craftsmanship. This eventually gave way to smaller, more diverse toolkits, with an emphasis on flake tools rather than larger core tools.
The Stone Age is a period in human prehistory distinguished by the original development of stone tools that covers more than 95 per cent of human technological prehistory. This image shows neolithic jadeitite axes from the Museum of Toulouse
These toolkits were established by at least 285,000 years in some parts of Africa, and by 250,000 to 200,000 years in Europe and parts of western Asia. These toolkits last until at least 50,000 to 28,000 years ago.
During the Later Stone Age the pace of innovations rose and the level of craftsmanship increased.
Groups of Homo sapiens experimented with diverse raw materials, including bone, ivory, and antler, as well as stone.
The period, between 50,000 and 39,000 years ago, is also associated with the advent of modern human behaviour in Africa.
Different groups sought their own distinct cultural identity and adopted their own ways of making things.
Later Stone Age peoples and their technologies spread out of Africa over the next several thousand years.
