Every parent at some time, faced with an overtired child going feral, has been convinced of the links to the animal kingdom.
But scientists this week confirmed it. They found that young children use tools instinctively to solve a problem, in the way that the great apes do, a finding that runs contrary to what we previously thought – that humans learned innovative use of tools through teaching.
The study, published in Proceedings of the Royal Society B, is the first to use tasks modelled on the behaviour of great apes to stimulate children’s cognitive responses.
Researchers at the University of Birmingham wanted to test the cognitive behaviour of children aged between two and a half and three years old, to see if they used tools to solve a problem without being shown how.
To make sure the children had no prior teaching, the researchers recreated 12 tasks that are usually faced by apes in the wild.
For example, apes may use a twig to extract kernels from nuts or seeds. The researchers replicated this by asking children to remove pom-poms from a box, a task which required the use of a stick as a leveraging tool.
Psychologist Claudio Tennie says the idea was to provide children with the right tools to solve the task, without explicitly naming them.
Some of the cognitive abilities behind tool-use are shared by humans and their closest living relatives.
“We told children the goal of the task, for example to get the pom-poms out of the box, but we never mentioned using the tool to them. We would then investigate whether children spontaneously came up with the correct tool behaviour on their own."
In 11 of the 12 instances, children successfully used tools to complete the activity.
The finding strongly refutes previous theories, including those of Lev Vygotsky, an influential psychologist in the early 20th century who argued that children only learn to use tools after being taught by those around them.
The findings also suggest that some of the cognitive abilities behind tool-use are shared by humans and their closest living relatives, the great apes.
This could pave the way for further investigation into shared behaviours and responses between primates.
"While it is true that more sophisticated forms of human tool use indeed require social learning, we have identified a range of basic tool behaviours which seem not to,” says Eva Reindl, a PhD student at the University of Birmingham's School of Psychology.
“Using great ape tasks, we could show that these roots of human tool culture are shared by great apes, including humans, and potentially also their last common ancestor."
An important take-away from the finding, according to the researchers, is the knowledge that our physical cognition skills have not diminished due to years of being taught to use tools.