A key aspect of human evolutionary success is the fact that we don’t have to learn how to do things from scratch. Our society has developed a variety of ways, from formal education to YouTube videos, to communicate what we’ve learned to others. This makes learning how to do things much easier than learning by doing, and it gives us more room to experiment. We can learn how to make new things or handle tasks more efficiently, and then pass on information about how to do it to others.
Some species close to humans, such as chimpanzees and bonobos, learn from their peers. They do not seem to engage in this iterative improvement process; that is, technologically speaking, they do not have a cumulative culture in which new technologies build on past knowledge. So when did humans develop this ability?
Based on a new analysis of stone tool making, the two researchers argue that this ability dates back relatively recently, to just 600,000 years ago – roughly the same time that our ancestors and Neanderthals went their separate ways.
Cultural Accumulation
It’s clear that much of our technology builds on past efforts. If you’re reading this article on a mobile platform, you’re benefiting from the fact that smartphones are derived from personal computers, and software needed hardware to function. But for millions of years, human technology has lacked clear components that could help us identify whether archaeological remains are derived from earlier work. So how do we study the origins of cumulative culture?
The researchers behind this new study, Jonathan Page and Charles Perrault, took a fairly straightforward approach. First, they focused on stone tools, the only things that have been well-preserved throughout human history. In many cases, tool styles have remained constant for hundreds of thousands of years. This gave us enough examples to understand how these tools were manufactured, and in many cases, to learn how to make them ourselves.
In their just-published paper, they argue that the sophistication of these tools is an indicator of when cultural accumulation began. “As new stone tool making techniques are discovered, the design space of possibilities expands,” they argue. “These more complex techniques are also more difficult to discover, master, and teach.”
This raises the question of when humanity made a critical transition: from simply teaching the next generation how to make the same kinds of tools to building on that knowledge to making new ones. Page and Perrault argue that it’s all about how complex the tool is to make: “Generations of refinement, modification, and happy mistakes produce skills and know-how far beyond anything any single naive human could have independently invented in a lifetime.”
