Language in deep history

‘In the beginning was the word’.

Well, in an archaeological sense it wasn’t. That human story begins with a stone technology two and a half million years old. Brains were much smaller, about half the size of our own. And instead of being a single, global species of seven billion, our highly varied hominin [i] ancestors were clustered in tiny numbers in parts of Africa. Moreover, nobody suggests that any of these different species of hominin could speak. What anatomical evidence survives points to the lack of a serviceable vocal tract and the fine breathing control needed for speech.

Artefacts start the story. Large brains followed with global settlement, a very late flourish on the timeline of human evolution.

So where does language fit into this deep history?

This was one of the questions that I set out to answer with co-directors Robin Dunbar and John Gowlett through the British Academy Centenary Project (2003-2010); From Lucy to language: the archaeology of the social brain. The Lucy project was interdisciplinary, bringing together the two halves of the British Academy. We combined the insights of an experimental science (psychology) with the evidence of an historical one (archaeology).

At its heart was the idea that our physical and cultural evolution was driven by our social lives. We measured those social lives through the changing sizes of hominin brains. Previously Robin Dunbar and Leslie Aiello had pointed to the good fit which exists in non-human primates between brain size and group size. When extrapolated to ourselves we find a figure of 150; known as Dunbar’s Number and best explained as the number of social contacts each of us is comfortable with before cognitive limitations kick in. When we started the Lucy project, Facebook was just a bright idea in a Harvard dorm. By the time we finished, its vast database of social networks had confirmed Dunbar’s Number; the average user has 130 Facebook friends.

How does this brain/group pattern link to language and the archaeological evidence? Aiello and Dunbar suggested that as brain/group size increased, hominins would need another way to create social bonds. Spoken language provided a time-efficient solution to reach the outer parts of a larger social network. The finger-tip grooming of apes and monkeys is just too time-consuming.

The implication of this idea is far reaching. Language emerged as a means to construct a larger social order. And, if correct, spoken language was very old indeed. It also suggested that hominins other than humans (ourselves) spoke. Suddenly the red-sofa of deep human history had a new and unexpected guest. Neanderthals could have been talking heads just like us.

But when did this happen and why? This is where archaeological evidence proves indispensable. We set out to investigate two routes to language using fire and technology as proxies. John Gowlett excavated some of the earliest traces of managed fire. He stressed the importance fire plays in extending the social day. It’s the night-time where language adds an imaginative dimension to social bonding through story telling. The development of composite artefacts from different materials – stone, wood, fibre and mastic – created, in project member Larry Barham’s words, something that does not exist in nature. He argues that the hierarchical cognitive structures needed to make such tools, are comparable to those required in a spoken language.

The social technologies of fire and complex tools, pointed us to the period between 800,000 and 400,000 years ago as the critical period in human evolution. It was a time of rapid brain growth in hominins such as Homo erectus, Homo heidelbergensis and even the earliest Neanderthals; all well before the appearance of Homo sapiens.

During this 400,000 year-long slice of deep human history the Lucy project traced the co-evolution of social network size alongside technological and cultural change. We did this at local and regional scales of hominin activity; for example the analysis of numbers living at ancient camp sites, the geographical scale over which raw material was moved and the use of material culture to build networks of variable density and connectedness.

What we didn’t find was a light-bulb moment indicating when language appeared. Neither could we find that it immediately made a huge difference. For example art and cultural symbols did not appear at this time. That happened some 250,000 years later. Bigger brains, it seemed, didn’t necessarily result in significantly cleverer or more sophisticated things.

We could have taken this finding to refute the idea that language is so very old. However, we did the opposite. By combining archaeology and psychology the Lucy project points to a completely new direction for the study of human evolution. Instead of language being directed at being clever with things or finding fancy new ways to express the numinous through art, it puts the spotlight on the everyday business of social life. Language fed instead into the emotions, that most basic of ways to build relationships and strengthen bonds between the rings of a social network. We will never know what these hominins spoke about. But we can be sure that they used the affect of language to great effect when it came to building the social core which still structures our lives; something that all social networkers know. In the beginning was the silence of stones and now there is the babble of smart-phones. The link between the two is the emotional language of social interaction.

Clive Gamble FBA is Emeritus Professor of Archaeology at the Centre for the Archaeology of Human Origins at the University of Southampton.

[i] Hominin bundles up us with all our fossil ancestors. For example, Homo erectus or Homo neanderthalensis may carry the generic moniker of Homo but they are hominins. Homo sapiens is the only human.