|PDF PRINT||Books and publications on the interaction of systems in real time by A. C. Sturt
Economics, politics, science, archaeology. Page uploaded 20 Oct 01, minor edit 30 June 04.
Print version added 1 June 2007.
|A Terrifying Creativity - from Hunter/Gatherer to Farmer|
|The Neolithic Transition|
|by A. C. Sturt|
Summary. Why humankind evolved to dominate the world is a problem for evolutionary biologists, but the processes by which it occurred are becoming clearer with advances in scientific techniques and the growth of systematic archaeology worldwide. The analysis presented here uses the methodology of goal-seeking learning systems to understand the interaction of humans with an environment which was ever changing, not least because of their own activity. The whole process is consistent with a system driven by hunger and the instinct for survival, just as with any other animal.
Hominids first appeared about 6 million years ago as a result of the stochastic processes of evolution. Modern Man, the supreme hunter/gatherer, evolved about a hundred thousand years ago, and is now the sole survivor of the different hominid species. His gradual rise to pre-eminence was the result both of greater ability to learn than other animals, and to accumulate and communicate what had been learned. But the decisive factor was the creativity that produced innovations, which were incorporated in the accumulated body of knowledge.
In effect, he continually moved the goalposts in the competition to survive in the face of other animals. However, the more successful he was, the more the population grew, and the more he needed to do to avoid starvation which limits the number of all other living things. The stage was reached when it was no longer possible to survive by hunting and gathering alone. He was forced progressively to take the innovative and revolutionary step of settling to grow his own food: the neolithic transition to farming.
This was the greatest, most fundamental change in the development of the modern world. Almost everything we associate with humankind stems from this transition: family, property, buildings, institutions, ceremony, law, hierarchy, farm drudgery, protecting crops and animals, protection of social status, in fact all the things with which we are now familiar. The surpluses accumulated from farming also made possible the development of metal smelting and working i.e. the Bronze and Iron Ages. A truly terrifying creativity, both theirs then, and now ours!
2. Modern Scientific Techniques
Everything we know about the past is coloured by the assumptions, institutions and facilities of modern life. Many activities which are now considered normal, even essential, were unknown a generation ago, because for instance the materials which make them possible either did not exist in sufficient quantity, or did not exist at all.
Even two generations ago it was a very different world; many of the technological advances which have changed ours were only just beginning to emerge from the wreckage of world wars. Go back a century and the dominant vehicle of our time, the car, was only just becoming relatively widely available, though soldiers were still riding into battle on horseback. No one yet flew anywhere. Go back a century and a half, and you find, surprisingly, transatlantic telegraph cables, but mainly wooden sail-powered ships of war and commerce plus railways and steam engines. And so on.
Thinking ourselves back into the past requires us to erase from our considerations all these and many more accretions to modern life, plus all their interactions with every aspect of our existence, many of which go unperceived until they become unavailable. For instance, the greatest hardship suffered by a family recently trying to reproduce the life of a century ago was not the absence of television or mobile telephones, but, unexpectedly, the lack of detergents. Even the smells were different in these relatively recent times; in Elizabethan times they would have been a stench. Would-be Iron Age dwellers in another experiment had to be rescued, because failure to observe simple principles of hygiene which are built into our everyday systems was endangering health.
How much more difficult then to think ourselves back to the earliest beginnings of mankind when he was still a hunter/gatherer. It is all too easy to fall into one of two broad views which may be caricatured as follows. The first is that hunter/gatherers had a rather idyllic way of life of roaming and living off wild fowl and (definitely organic!) fruits, nuts and berries. They left some wonderful paintings and beautiful stone tools, but it could not last, and they finally had to settle down to a more responsible way of life i.e. one with which we could feel more comfortable. The other extreme is the view that that life was just nasty, brutish and short. And lurking in the background is another caricature, this time from evolution: that man started off on all fours, but after years of trying, managed to walk increasingly more upright until he became the upstanding biped which is ourselves. It all leads to the rather smug conclusion that we are so much more 'advanced' than they were, which probably means cleverer
None of this bears even the most superficial scrutiny in the light of today's knowledge. There is no evidence at all that we are 'cleverer' than early modern man, though we are certainly later. A short life he may have had, but whether it was nasty depends on our tastes in hindsight. Brutish it most certainly was not; no brute or its descendants ever came to dominate life on earth. Nor was it idyllic, though there may well have been blissful, carefree interludes for many.
2. Modern Scientific Techniques
Modern scientific techniques are enabling us to delve ever deeper and in a more informed way into the nature of things, not least the changing environments which have obtained in the past on the earth. Archaeology is increasingly bringing the same techniques to bear on the past of man himself, a glimpse of developing biological, social and technological systems through those of their artefacts which happen to have survived. The dates of artefacts and events can often be established with astonishing degrees of precision through techniques such as carbon dating and dendrochronology, where it is sometimes even possible to say whether a tree was cut down in the spring or the autumn of a particular year thousands of years ago, and whether it was a warm year with reasonable rainfall or exceptionally cold and waterlogged. The species of tree can be unambiguously identified. Pollen analysis can show what was growing in the locality at the time, with microscopic remains of insects as confirmation. Chemical analysis shows the provenance of stone used for making artefacts and clay used for making pots. Other techniques may show the temperature at which pots were fired, that is the state of kiln technology at the time.
Even further back into the past, oxygen isotope analysis of Greenland ice cores can tell us annual temperatures going back many thousands of years, as well as the composition of air trapped as bubbles at the time: carbon dioxide content, sulphur dioxide content and so on. They may also contain ash from identifiable volcanoes deposited from eruptions which occurred thousands of years ago, so that their date can be precisely established. Calculations from the various cycles of the earth's orbit around the sun show the basis of the broad oscillations of global temperatures which have occurred during man's time on earth. Plate tectonics, a much derided theory until only a few decades ago, shows the pattern of volcanic activity. And so on.
Genetic analysis is also revealing the biological derivation of man himself. Two features stand out above all others: first, the astonishingly small variation of DNA between one person and another, of whatever origin; secondly, the surprisingly small average variation of DNA between peoples who have always appeared to others, and have certainly always considered themselves, as genetically distinct. Such variations turn out to be of the order of a small fraction of 1%. Nevertheless there exist identifiable groups of genes, albeit difficult to detect, and they suggest that ancient peoples do not just cease to exist; they melt away into the locality which their civilisation once dominated. Many descendants, though undoubtedly much homogenised through intermarriage, are likely to be alive and well and living in the same region as their forebears. This is visibly true of peoples in Southern and Central America. The same sort of analysis shows the patterns of migration across the globe. Reconstruction using forensic techniques of faces from bone structures of the long since dead, suggests that they looked, surprise, surprise, just like us. Not till we reach back to Neandertal times do we see faces which look markedly different from anything we can see around us today.
Armed with these new perspectives on the world, we can begin to construct the sort of process by which man came to his present dominance, and particularly the transition from hunter/gatherer to farmer. He was subject, of course, to the environmental pressures and fluctuations which influence all creatures, most visibly large predators such as ourselves. There is no way in which he could have been immune. But uniquely for man there is the social, cultural and technological development which interacted with and eventually changed the environment in which the process was taking place: a purposeful and determined response to the vicissitudes of changing environments.
accuracy of dating
Greenland ice cores
oxygen isotope analysis
minuscule variation of DNA
interaction with environment
3. The Methodology of Learning Systems
The clearest way of describing the process is as a goal-seeking learning system driven by hunger. A system consists of parts which interact, so that they are all essential to its survival. It takes inputs from the environment and transforms them into outputs. For an animal 'system' these might be food and water taken in and excreted after processing to extract nutrients. A goal-seeking system is one which is not simply operating, but which is trying to reach a certain state or goal. For our animal this would be the survival of the species, not only itself but its offspring, or it would be the last of its line. A learning system learns how better to achieve its goal by assessing the outcome of its present performance, so our animal will know better what to do next time the occasion arises.
A successful living system reproduces itself faster than it dies, or chance events, which always occur, will progressively wipe it out. It will produce more systems which will also be successful, and so on. A simple example is bacteria, which multiply in geometrical proportion. The process reaches a point when growth is limited by the availability of inputs for all the systems which have been produced i.e. food and water. So bacteria stop reproducing when they run out of nutrients. But there is another factor which is predation. At some stage predators destroy systems as fast as they can be formed.
Predation and availability of inputs set the limit on the spread of the living systems concerned, and so a balance with the environment is reached. That does not mean a limit on other types of system living in the same locality. They may take different inputs from the same environment, like different wading birds feeding at different depths, and they may have different predators, which affect their overall success differently. The availability of inputs for them is different.
Applying this principle to animals, say bears, you might expect the species to spread over the whole earth. Each bear would occupy an area sufficient sustainably to provide it with inputs, allow reproduction, refuge from predators, and so on. Each bear would be in competition with every other bear, so that there would be a restriction on its success quite apart from the above, but the species as a whole would eventually cover all the available area as we have defined it.
interaction of parts
fill all available area
|Copyright A. C. Sturt 4 September 2001||continued on page 2|