New research from Oxford University has revealed that chimpanzees demonstrate limited engineering capabilities that aid them in retrieving insects as food sources, findings that offer a rare perspective on the evolution of tool use among human ancestors.
The new findings, reported by a multidisciplinary team led by Dr. Alejandra Pascual-Garrido, reveal how chimpanzees in Tanzania select certain plants that offer optimal materials for “termite fishing,” where long, thin portions of plants are used to extract insects from their nests for consumption.
The new findings help to shed light on how early tool use and pre-engineering capabilities developed among early human groups. This ultimately led to the creation of tools made from perishable materials such as wood that cannot be preserved over such long periods and studied today, unlike those crafted from stone.
Engineering Among Apes
A Research Affiliate at the School of Anthropology and Museum Ethnography at the University of Oxford, Pascual-Garrido and her team studied the behavior of chimpanzees living in Tanzania’s Gombe Stream National Park. Several of the primates were observed methodically selecting the plants they used for termite fishing.
Chimpanzees often seek out these insects as a food source because they provide ample fat, vitamins, and protein. However, extracting the insects from the meandering tunnels they dig requires flexible fishing tools.
The international team led by Pascual-Garrido used a mechanical testing device during field studies, allowing them to determine the force required to bend certain plant materials. Specifically, the team made comparisons between the tools the apes were observed using and measurements of varieties of plants that had never been seen in observations of chimpanzees engaged in termite fishing.
As the researchers expected, plant species that chimpanzees had never been observed using were as much as 175% more rigid than those that chimpanzees are seen using to extract the insects from their nests.
Additionally, plants growing near termite nests that bore signs of use by chimpanzees were among the most flexible available in the immediate area.
Dr. Pascual-Garrido called the team’s findings “the first comprehensive evidence that wild chimpanzees select tool materials for termite fishing based on specific mechanical properties,” building on more than a decade of observations she has conducted in the field.
Not All Plants Are Equal for Termite Fishing
Pascual-Garrido says that her team’s findings could point to a deeper culture of tool-making among chimpanzees throughout the immediate area and surrounding regions. Of particular interest in the team’s findings was that plants such as Grewia, a species in the Malvaceae family that grows in Tanzania, have also been shown to be a preferred material for tools by chimpanzees as far as 5,000 kilometers away.
Therefore, it is possible that chimpanzees may intuitively understand certain properties of materials, allowing them to select the ones that will perform the best for such food-gathering activities.
“This novel approach, which combines biomechanics with animal behavior, helps us better understand the cognitive processes behind chimpanzee tool construction and how they evaluate and select materials based on functional properties,” Pascual Garrido said in a statement.
The Origins and Transmission of Knowledge
The team’s findings raise a few significant questions, especially regarding how knowledge is learned and maintained by groups. Even more importantly, the new findings focus on how knowledge is transmitted and whether learning by younger generations primarily occurs through observations of parents and other elders.
Adam van Casteren, a researcher involved with the study and part of the Department of Human Origins at the Max Planck Institute for Evolutionary Anthropology, said the team’s findings have very important implications for understanding how early human ancestors would have evolved such engineering and toolmaking capabilities themselves hundreds of thousands of years ago.
“While perishable materials like wood rarely survive in the archaeological record, the mechanical principles behind effective tool construction and use remain constant across species and time,” Casteren said in a statement.
Ongoing studies of chimpanzees and their rudimentary engineering capabilities through the selection of materials will ultimately help researchers to untangle the many remaining questions about human evolution and the use of tools throughout time. Also of key importance is that chimpanzee material selection based on their properties can help anthropologists gain insights into the limitations early humans might have faced while engaging in similar activities.
Although such materials would not have survived in the paleoarchaeological record, studying such primate behaviors in modern times offers a unique window to the past and a potential glimpse at the behaviors of our early ancestors that ultimately sowed the seeds of modern technological progress.
The new study, “Engineering skills in the manufacture of tools by wild chimpanzees,” by Alejandra Pascual-Garrido et al., was published in iScience on March 24, 2025.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.