How far back can we go?

This column prides itself on taking quite a long, steady view of things. But a recent presentation made me think the tortoise-like perspective of Slow Lane, which disdains the immediately topical, was pretty short-sighted.

Professor Chris Stringer, research leader in human origins at the Natural History Museum, London, was giving a talk about the discovery of a cache of razor-sharp flint-cutting tools in a bed of 900,000-year-old sediment near the village of Happisburgh in Norfolk. The significance, in case you missed it (it was reported in July, in the journal Nature) was to push the earliest dating of human occupation of Britain – that is occupation by Homo antecessor, ancestor of Homo sapiens – back by roughly 200,000 years.

Prof Stringer is an academic with a natural gift for communication. He began his talk by extending a tape measure to a length of 9m. If that represents the 900,000 years human beings have existed, on and off, in Britain, then the last 2,000 years, since the coming of the Romans, are represented by 2cm of tape. The period since the Industrial Revolution comes down to the paring of a thumbnail.

The time-frames of palaeontology are clearly very different from the ones we usually employ. They are also just a bit more graspable than the unimaginable slownesses of geological time. After all, we are talking about our human ancestors, beings from whom we are descended.

Everything seems very bunched up now, in terms of historical perspective. We can feel squeezed between a century of appalling wars and human genocides and a near future of global warming and ecological hecatombs. This perspective is not necessarily wrong but it could do, I began to feel as I listened to Prof Stringer, with a bit of unwinding. Almost one million years of human presence in Britain encompasses, for a start, changes in climate and geography beside which even the most pessimistic current forecasts seem quite tame.

Take the glacial periods within the Quaternary ice age, which started two and a half million years ago and is still continuing. We speak about these quite glibly but perhaps we do not grasp the devastating effect and reality of two-mile-thick sheets of ice blanketing our familiar landscapes, reconfiguring those blue remembered hills into unrecognisable new forms. Of course, humans could not survive these glacial periods and time and again the human communities that had established themselves in northern Eurasia and North America were wiped out. But each time our intrepid, hopeful ancestors came back.

In between the glacial periods there were warm interludes, warm enough for hippopotamuses to wallow in the Thames, and for lions and elephants to roam in the savannahs of Surrey. Through these dramatic changes and vast spans of time the human project continued. It started on a very small scale; Prof Stringer and his colleagues say there were only a few hundred or at most a thousand or two humans living in Britain at the time when the Happisburgh flint tools were chipped.

How “primitive” were these ancestors of ours? They were certainly adept with their hands; it takes a lot of skill to make a flint cutting tool with a finely honed edge. They were probably quite good at hunting mammoths and avoiding sabre-toothed cats. Environment, for them, did not mean something abstract, to do with government or EU directives, but overwhelmingly powerful forces of nature.

The main way in which they differed from us was that they were not so technologically innovative. The stone and flint tools that survive from the stone age are beautifully produced but they remain pretty much the same over great spans of time.

Palaeontology doesn’t offer any easy answers to our current predicament – to the fact that, as the social theorist Ulrich Beck glumly puts it, we seem to be rendering the earth uninhabitable. We have more knowledge (at least of certain kinds) than our ancestors, more of that god-like capability of looking before and after, deep into the past and far into the future, and more sophisticated technology, but all that knowledge and technics hasn’t brought wisdom.

You could say the parts of it that relate to the future are fatally hedged with uncertainty. We know pretty much for sure, as they presumably did not, that at some point the ice sheets will return to blanket London, Paris, Moscow, New York. But we are also pretty sure now (more than 90 per cent sure, according to the UN’s International Panel on Climate Change) that, in the shorter term, our own activities are causing a dangerous, potentially disastrous, warming of the climate.

The complexity of the different factors that influence climate, and their potential interactions, is so great that we will never have certain knowledge of them. But I think if we were as brave as our ancestors, we would take a bet on our limited knowledge, and wager that we knew enough to justify a precautionary approach.

harry.eyres@ft.com

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