Early humans appear to have experienced a sudden and rapid technological advance around 600,000 years ago, according to new findings from a team of anthropologists exploring the use of ancient stone tools.
The researchers behind the findings say this likely represents a key inflection point in ancient human development, where the transfer of ancient knowledge from generation to generation, known as cumulative culture, led to increasing progress in society that have propelled the biological, cultural and technological development of humanity.
“Our species, Homo sapiens, has managed to adapt to ecological conditions – from tropical forests to the Arctic tundra – that require solving different types of problems,” said Associate Professor Charles Perreault, an anthropologist from the school of Human Evolution from Arizona State University. and social change. and research scientist at the Institute of Human Origins. “Cumulative culture is essential because it allows human populations to build on and recombine the solutions of previous generations and develop complex new solutions to problems very quickly. »
Toolmaking Suddenly Experienced Rapid Technological Advancement
In their published study, “3.3 million years of stone tool complexity suggests that cumulative culture began during the Middle Pleistocene,” appearing in the journal PNAS, Perreault and his colleague Jonathan Paige, an anthropologist at the University of Missouri, explain how their analysis of stone tools from 3.3 million years ago revealed this sudden and unexpected technological leap.
The researchers analyzed tools collected from 57 distinct ancient hominid sites. The oldest tool, dating back more than 3 million years, came from an African site. However, researchers have also studied ancient stone tools found at ancient hominid sites in Eurasia, Greenland, Sahul, Oceania and the Americas.
Next, the team ranked the complexity of the tools. This involved analyzing the number of steps required to create the tool in question. Researchers characterized and classified 62 distinct toolmaking sequences.
After analyzing the complexity of the tools, the team noticed unexpected trends. Tools made between 3.3 and 1.8 million years ago required between two and four procedural units to make. The complexity of stone tools continued to increase over the next 1.2 million years, with the best samples requiring an impressive seven steps. Although significantly more complex than tools made more than a million years earlier, researchers say it’s still within the range of complexity for a single craftsman. This means that the knowledge of previous generations of toolmakers was probably not passed down during this period.
However, the researchers found that when they looked at tools made around 600,000 years ago, in the Middle Pleistocene, they began to see a sudden and unexpected increase in complexity. The tools of this period were not only more complex, but also more complex manufacturing processes were required to make these tools.
“We analyzed stone tools made over 3.3 million years,” the researchers explain. “We found that these stone tools remained simple until around 600,000 BP. After this date, stone tools rapidly increased in complexity.”
While making previous tools required only a few procedural steps, tools from this era often required up to 18 steps. According to Paige and Perreault, this represents far too many steps for a single generation of artisans to complete without the knowledge passed down from previous generations.
This evidence, the researchers write, is consistent with the findings of other research teams, suggesting that such a rapid transition “signals the development of cumulative culture in the human lineage.”
“About 600,000 years ago, hominid populations began to rely on unusually complex technologies, and we only see a rapid increase in complexity after that time as well,” Paige said. “Both of these results are consistent with what we expect to see in hominids that rely on cumulative culture.”
The dawn of cumulative culture and the evolution of modern man
Although the evolution of stone tool making provides evidence of the dawn of a cumulative culture, the researchers behind these discoveries say such a leap likely affected every aspect of early humans . This likely included changes in human culture, biology, and even the ability to adapt to a range of environments and habitats found across the world.
“Human dependence on cumulative culture may have shaped the evolution of biological and behavioral traits in the hominid lineage,” explain Paige and Perreault, “including brain size, body size, life history, sociality, subsistence and ecological niche expansion”.
Such changes may become more complex as genetic and cultural evolution occur simultaneously. According to the researchers, this “process of gene-culture coevolution” could explain increased relative brain size, a prolonged life history “and other fundamental traits that underlie the uniqueness of the human being.” .
The researchers particularly point out that the Middle Pleistocene presents many other examples of technological evolution. For example, studies from this era reveal consistent evidence of controlled use of fire, hearths, and other domestic spaces. This era also shows the evolution of wooden structures built with logs hewn using hafted tools which, the researchers explain, “are stone blades attached to wooden or bone handles.”
In their conclusion, Paige and Perreault note that toolmaking is only one measure of cumulative culture and that further study could uncover other increases in this behavior that may have occurred in the past but which are not immediately evident in the archaeological record. “It is possible that early hominids relied on cumulative culture to develop complex social, foraging, and technological behaviors that are archaeologically invisible,” they write.
Ultimately, the research team believes their results show how knowledge can be passed down from generation to generation without each successive generation having to rediscover knowledge from the past. When enough knowledge comes into expression, as appears to have happened 600,000 years ago, this process can result in an ever-growing and adaptive pool of knowledge that allows for steady upward progression. cultural and technological evolution.
“Generations of improvements, modifications, and lucky mistakes can generate technologies and know-how far beyond what a single naive individual could independently invent in their lifetime,” the researchers conclude. . “When a child inherits the culture of his parents’ generation, he inherits the result of thousands of years of mistakes and lucky experiments.”
“The result is that our cultures – from technological problems and solutions to the way we organize our institutions – are too complex for individuals to invent on their own,” Perreault adds.
Christopher Plain is a science fiction and fantasy novelist and senior science editor at The Debrief. Follow and connect with him on X, check out his books at plainfiction.com or email him directly at christopher@thedebrief.org.