Young chimpanzees are remarkably innovative, inventing tools and improving on ones that adults use - and this technical know-how could hold the key to better appreciating the role of children in the evolution of all cultures, including ours.
That's what scientists led by an anthropologist at Université de Montréal conclude in a new study.
Published in the Nature journal Scientific Reports, the paper explores the tool-making skills of three dozen immature chimps at the Ngogo research site in Kibale National Park, a heavily forested area in southwestern Uganda where a large population of chimps live in the wild.
"This paper is about evolution of culture in humans, using chimps as a model of comparison, and the take-home message is that children could be more important figures in cultural evolution than previously thought," said Bădescu, an associate professor of anthropology at UdeM.
"At their stage of development kids are allowed to be creative and to explore. They can experiment with tools and objects and this leads to new and innovative ways of using them. It introduces variation into the repertoire of skills that adults can pick up on, and that's how culture evolves."
In Uganda, where she spent much her time studying chimps, Bădescu has observed that kids intelligently used moss as a sponge tool to soak up and drink water, for instance.
"We don't often think of kids as being the innovators of technology, but they can indeed be important," Bădescu said. "For anyone interested in how culture is created, regardless of their academic disciplines, these observations and results should be quite interesting."
Origins of innovation explored
In her study, done with scientists at Arrhus University in Denmark as well as the University of Toronto and Yale University, Bădescu notes that innovation drives cultural evolution yet little is known about its developmental origins or the role of immature individuals generating novel behaviors.
Over 15 months in 2013-2014 and 2018, Bădescu examined 67 different uses of objects by 36 infant and juvenile chimpanzees (Pan troglodytes schweinfurthii) at the Ngogo field site. Nearly half of those uses were atypical, deviating from adult norms, she found.
Of those, almost all - 94 per cent - were new uses or modifications of adult forms or uses in new contexts, including three innovations: playing with a "doll" (a tree stump carried as if it were an infant), sponging up water with a tuft of moss, and clipping leaves to signal wanting to be carried.
Others used stick tools to probe for and eat honey from honeycombs, as well as to fish for and eat termites. They also used tools in social contexts, for instance 'leaf grooming' of each other, much like the adults do, but in their own way.
An 'exploration index'
To assess individual differences, Bădescu and her team developed an "exploration index" integrating frequency, diversity and atypicality of object use. Nine individual chimpanzee children had notably higher scores.
Females and offspring of mothers of several children scored higher, indicating the positive effects of sex and social support from experienced mothers and siblings.
"These findings suggest that immatures generate novelty at the margins of species-typical behaviour yet vary in their propensity to innovate," the co-authors conclude in their study.
"A permissive social environment for object play may be key to the developmental pathways of innovation, providing a generative context for behavioural variation on which social learning and selection can act," they write.
"If retained and transmitted, even rare innovations by immatures could contribute to the accumulation of cultural complexity."
