Thousands of years ago the San tribe put their keen observations of plants and insects to use by making lethal poison arrows that brought down huge game.
There’s more to discover from this interaction between ancient cultures and the environment, said Andrea Weeks, a George Mason University botanist and co-author of a new study of this tribe. Researchers are working against cultural changes that are cutting that connection as these hunter-gatherers transition to a more modern lifestyle, she added.
The multidisciplinary study combines anthropology, botany, entomology and chemistry, and could impact the public policy that’s driving the cultural change of the San tribe.
“What else are we losing besides this knowledge as indigenous groups lose their cultural heritage?” she asked.
The San tribe includes several groups in southern Africa who use the “click language” and are more commonly known as “Bushmen.”
Some tribe members use ground-up beetle larvae mixed with saliva and apply the poisonous mixture to arrows. Other tribes use the milky plant sap of Adenium bohemianum, which belongs to the milkweed family. The milkweed plants that grow in Virginia are typically not as toxic, said Weeks, who specializes in the plant family that also includes frankincense and myrrh, and contributed the plant information to the research paper.
But the real twist comes when the plants and beetles are combined, Weeks said. By digging down near the roots of myrrh trees and harvesting beetle larvae eating the roots, Bushmen are able to concoct a poison powerful enough to bring down large animals such as elephants and wildebeests with their arrows, she said.
Very little is known about how some insects boost their inherent toxicity by dining on certain plants, said Weeks, adding she hopes to continue the research.
What is clear is that humans took advantage of a war between the plant and insect worlds. Plants use toxins to defend themselves from hungry insects and other animals while insects develop resistance so they can eat the plants, Weeks said.
“It’s like an arms race between herbivores and plants,” she said. “It’s been going on for hundreds of millions of years. How the San tribe uses it to make poison arrows shows that humans have been aware of the connection for a very long time.”