Since instruction is often perceived as an essential means of learning, traditional education seems more of a requirement than an option in today’s society. However, instruction as a way of teaching may not be necessary for individuals learning to make tools.
In a study released Thursday, Alex Thornton, a lecturer at the University of Exeter in the United Kingdom, and Elena Zwirner, a doctoral student at University College London, observed that tools and technologies developed by humans have consistently improved over time. In efforts to point to an explanation for such quick advancement, the researchers recruited participants to build rice baskets from ordinary materials, either alone or performed via a “transmission chain.”
“We ran transmission chain experiments in which the first person in the chain was asked to make a tool from everyday materials,” Thornton said in an email. “The next person in the chain could learn from the previous person either through imitation … teaching … or emulation.”
Thornton stated that across chains of six people, the baskets improved in efficacy regardless of whether or not people followed the three methods of learning. And as the two researchers stated early on, this phenomenon was present in the past as well.
David Carballo, a professor in the College of Arts and Sciences at Boston University, said in an email that early human ancestors were making stone tools 3.3 million years ago.
“The tools were pretty basic — chip that we call flakes, hit off a larger stone we call a core,” he said. “They would have been useful for skinning animals and cutting off bits of meat from animals that had been killed by larger predators … or [that] died by natural causes. They could not have been used for hunting or butchering large animals.”
Carballo said this changed 1.8 million years ago, when species such as the Homo erectus began to hunt large animals.
“Tools continue[d] to get more and more sophisticated, including the use of projectiles, the invention of fine blades and the making of composite tools where stone blades were put into ivory or bone to make knives, harpoons and other more elaborate tools,” he said.
Curtis Runnels, a professor of archaeology in CAS, teachesa class called “Ancient Technology,” in which he has previously taught undergraduate students how to make primitive flaked stone tools.
“In my experience over 42 years, students need initial training, both visual and verbal, in the method,” he said in an email. “After that, experience and emulation will allow students to make rapid progress on their own.”
Thornton, however, said his study revealed that emulation was just as effective given the fact that people are good at reverse engineering when it comes to constructing tools.
“People seem to be able to reason about the causal structure of artifacts and the intentions of the designer even if they did not get the chance to learn directly through observation or teaching,” he said.
He then suggested that causal reasoning is a crucial aspect of human intelligence.
“In the past, research on cultural evolution has tended to focus on the social intelligence and social learning,” Thornton said. “This work suggests that individual cognitive abilities are also critical.”
Runnels added that after 3 million years of co-evolution, humans possess the intelligence to create. However, he said he still believes instruction is of crucial importance.
“The eye, brain and hand are hardwired to make things, everything from stone tools to atom bombs,” he said. “…[The study] seriously underestimates the role of verbal instruction in the making of stone tools, and that teaching is in all cases an essential first step in learning anything.”
Carballo observed a difference between making stone tools, as our predecessors did, and making rice baskets, as the subjects of the study did.
“One major difference between making stone tools and making rice baskets is the first is what we would call a reductive process, meaning you start with something larger and end up with something smaller,” he said, “whereas the second is an additive process, where you gradually build pieces into something larger.”
Flintknapping, or the making of stone tools, for instance, is a reductive process with a learning curve that is steeper. If a stone is hit a certain way, it will shatter. Carballo noted that while weaving baskets, one can keep positioning strands incrementally and will not have the same sort of “total” failure.
“It will be obvious by looking at the baskets of an expert and a novice what the skill level is, but the learning curve is less steep,” he said.
From Thornton’s point of view, it is clear that the majority of animal species have simple forms of culture that spread as a result of individuals learning from one another.
“Only humans seem to exhibit cumulative culture, whereby the products of culture … build in efficacy and complexity over time,” he said. “This study was an attempt to understand the cognitive processes that make human culture possible.”
In the future, Thornton said he would like to run this sort of study with people from a variety of countries.
He added, “There is a lot of work suggesting that learning styles vary across the globe.”