When did humans begin accumulating social knowledge?

A key aspect of humans' evolutionary success is the fact that we don't have to learn how to do things from scratch. Our societies have developed different ways – from formal education to YouTube videos – to transmit what others have learned. This makes learning how to do things much easier than learning by doing, and gives us more room to experiment; We can learn how to build new things or handle tasks more efficiently, and then pass on information about how to do it to others.

Some of our relatives, such as chimpanzees and bonobos, learn from their fellow species. They do not seem to engage in this iterative improvement process, as they do not, technically speaking, have an accumulative culture where new technologies are built on previous knowledge. So when did humans develop this ability?

Based on a new analysis of stone tool making, two researchers argue that this ability is relatively recent, dating back only 600,000 years. This is roughly the same time that our ancestors and Neanderthals went their separate ways.

Accumulation of culture

It's very clear that a lot of our technology builds on previous efforts. If you're reading this on a mobile platform, you're taking advantage of the fact that smartphones are derived from personal computers and that software requires working hardware to happen. But for millions of years, human technology has lacked the kind of clear building blocks that would help us determine when an artifact has been extracted from previous work. So, how do you go about studying the origin of cumulative culture?

Jonathan Page and Charles Perrault, the researchers behind the new study, took a very direct approach. Initially, they focused on stone tools because they were the only things that were well preserved throughout the history of our species. In many cases, tool patterns have remained constant for hundreds of thousands of years. This gives us enough examples that we have learned how to make these tools, and in many cases we have learned how to make them ourselves.

Their argument in the paper they have just published is that the complexity of these tools provides a measure of when cultural accumulation began. “As new knitting techniques are discovered, the boundaries of the potential design space expand,” they say. “These more complex technologies are also more difficult to discover, master and teach.”

The question then becomes when did humans make the major shift: from simply teaching the next generation how to make the same type of tools to using that knowledge as the basis for building something new. Page and Perrott argue that it has to do with the complexity of making the tool: “Generations of improvements, modifications and fortunate errors can generate techniques and knowledge far beyond what a naïve individual could independently invent during a lifetime.”