32 Issues of cultural evolution for an Archaeologist

D. K. Bhattacharya

Ever since socio-biologists started addressing a large array of socio-cultural issues in trying to understand their evolution, both physical and social anthropologists generally started treating such discourses with disdain. This may be possibly because neither of these sub-disciplines could decide upon a methodology which combines the precepts of both these specialised branches. For Prehistorians, however, primate ethology and hunter-gatherer ethnography were the only channels through which he could negotiate his interpretational arguments. Consequently addressing issues of cultural evolution or social formation remain perfectly legitimate branches in what has come to be known as „Anthropological Archaeology‟. In fact Academic Press even brought out an international journal of this name some decades ago.

Archaeologists deal with antiquities and these do not speak. Consequently much of our culture interpretations remain not only tentative but also segmentary. It is through anthropological wisdom alone that we can construct a continuous story of the past. Issues of cultural evolution when sought through a study of the antiquities within the frame work anthropological knowledge starts giving a range of extremely important possibilistic features.

Emergence of man as a dominant species in the animal kingdom is viewed in different way by different specialists. Scientists, seers and philosophers have all tried to understand this process but a fuller comprehension of how mankind emerged has always eluded them. It is like chasing one‟s one shadow. However, almost all species agree that if this animal has successfully survived under numerous threats arising all through his existence, it is only because in addition to his biotic abilities he had developed an extra apparatus called „culture‟. It was argued that although man was a part of the environment his culture is not. Further, it is a non-tangible package of behaviour which is passed on from one generation to another by the process of enculturation. Since operative part of this is non-tangible it is transmitted as a narrative with significant codes which combine together to form the cognitive world of the group. The problem of identifying these codes is very succinctly delineated by Sperber (1996). He uses the example of a dog marking its smell as a code of information to other dogs. In archaeology most of us deal with the products of such an enigmatic, invisible and extra somatic feature of mankind and through these antiquities try to decode the cognitive mind of its creator. Trying to understand the process of evolution of this factor called culture, therefore, becomes of importance to study.

Experts working on human evolution and also archaeologists seeking to unravel human activity found many works of earlier explorers‟ account very useful for tracing analogies of the past. The heightened interest in such “primitive” societies in the subsequent century is reflected in the form of such publications as those of Marshal Shalins (1972) who floated the concept of “Original affluent society” for these hunter- gatherers. If fossil hunting became important for understanding biological evolution of man, hunter- gatherer studies became as important to understand cultural evolution of man.

Palaeoanthropologists were never sold out to any trite and populist way of understanding the past. They depended entirely on scientific factors to reconstruct the why and wherefore of the process of hominid change on more substantic hardcore evidences. Diverse evidences from diverse periods seldom yielding the same anatomical parts were painfully gathered to form a complete picture. The story of human evolution was therefore more of a collage and it soon got nicknamed as the “nut cracker model”. It proposed that during hominid evolution sometimes around 14 to 18 million years ago terrestrial adaptation was forced on an otherwise brachiating group of primates. Among other things this caused a reduction of the canines and the masticatory apparatus. It is argued that the nuts, edible roots and tubers available in the ground had hard shells. These required a grinding function of the jaws which was possible only when the jaws, teeth and the masticatory muscles were re-adapted to sideways or grinding motion. The first structural change that had emerged as a consequence was the reduction of the canines and with this a chain reaction was let loose.

The heavy jaw was slowly reduced and the muscles attached with it started pulling the sides of the skull. Thus, within a period of 6 to 8 million years an elongated nut shaped skull having an inner volume of only 450 c.c. becomes rounded with the inner volume increasing first to 600 c.c. around 4 million years ago and then to 1000 c.c. around 2 million years ago. Nature abhors empty space and hence the brain cells multiplied to fill up this additional space. Thus, extremely complex neo-cortical areas were developed during the path of evolution. These have demonstrated how the areas of association and recording of experiences steadily develops into a stage where knowledge of the actual could lead to the thought of the possible.

Thus, what started with a struggle to adapt to ground living eventually allowed man to have a better and larger brain capacity. This not only enabled him to store various experiences but also recall these experiences to develop better strategies of adaptation. For instance, our ancestors or early man must have cut his toes on sharp stones spread around natural water sources. He could recall this experience when he had to cut and cure a hunted animal. He now picks up or fabricates a stone to be used as a tool to do these functions which his sturdy canines used to do earlier. Construction of this extra somatic medium marks the beginning of culture.

The earliest ancestors of man emerged in a Savannah kind of ecology. He chose a far more open area than the chimpanzees were used to. Further all evidences known till date tend to indicate that their population density must have been less than the same in some of the contemporary chimpanzee groups. Osteological and archaeological evidences strongly suggest an increase in non-vegetarian diet in early man at this stage. The use of more comprehensive verbal language in order to integrate co-operative behaviour among the members of a group must have started around this time. We know that almost all species have a genetically coded call which ranges within a span of few responses and these do not have to be taught to them. Evolution of Brocca‟s center and multiplication of the neural sensory network enables our ancestors to increase the range of verbal codes, but these speech modules in man needs to be intentionally taught unlike in all other primates. As a consequence of this new ability man could now transmit experience to the filial generation. Experiences of all successive generations in this manner can get accumulated as knowledge. Soon man starts taking advantage of this knowledge in making choices for progressively successful adaptation.

A similar cultural tool that played a fundamental role in laying down the foundation of culture was man‟s ability to domesticate fire. Since as a species he evolved within an east African ecological background his genetic mechanisms for adaptation is totally tuned to sub-tropical environment. If, therefore, he could survive in another eco-zone, it is primarily because he could draw on culture as an additional tool for adaptation. However, culture is not identical in description to all mankind. Somewhere around 400,000 years from today man changes the pattern of foraging practiced earlier. This changed pattern is called „Home based economy‟. Earlier bands used to continue foraging within a forest and also sleep there at night to continue foraging in the morning. It is argued that in order to keep the fire fed with dry leaves and also because of weaning mothers and extremely dependent offsprings man chose to come back to the home base every night. After exhausting edibles around a temporary home base they could always move to another base. The choice of a base was also decided by availability of water in the neighbourhood. This change brought about close interaction within the members of the band and helping in the creation of a group solidarity. To guarantee group life and to enable the continuity of the species nature brought about another important change. To ensure the reproduction of such a highly complex being as man a biological system of year round sexual receptivity had to be evolved. That is with the withdrawal of rut man and mind was put under the influence of a battery of entirely new hormones which started influencing all his interpersonal behaviour.

The emerging human kind was progressively getting larger brain because of their selective advantage. The hip bone was also being progressively modified by the same process to afford an efficient bipedalism. A stage comes in these dual changes when the large brain box becomes too big to come out of the narrowing birth canal. Nature decided to terminate gestation before the full development of the foetal brain box to solve these two opposing forces of evolution. Thus, more than sixty percent of a human baby‟s brain develops outside mother‟s body. Consequently a human child is the most helpless child at birth when compared to other animals. This extended duration of dependency of the child allows more time for learning basic emotions and their symbolic vocalisation.

Many experts believe that delayed maturation was one of nature‟s methods to allow adequate time for learning because much of human survival had to depend on learned behaviour. The extreme importance of this mother-child bonding for the survival of the species can also be demonstrated by the fact that bio-chemically it is also controlled that the mother does not ovulate and hence another child is not born until the first one is out of mother‟s milk. Increased bonding because of home based foraging in addition to the introduction of hormones which control a new range of emotions must have eventually led to a situation where one or two mother-child pairs got attached to one or more males in the band. This must have led to the formation of a prototype of family. Soon these units become definable in terms of economic production. To hold such units together within a larger group or band a stronger social system needs to be evolved and all specialists agree that such a social system was evolved from as early as the Neanderthals (about 100,000 years ago). The evidences from Shanidar cave in Iraq substantiates how both emotion and altruism had already developed in man at this stage.

It was the pressure to extend the effectiveness of family unit in organising the task of production and survival that led man to fashion rules of conduct and their institutionalisation within the members of a band and also between bands. Mate regulation must have evolved subsequently to diffuse sex competition or even to seek stability of a large group solidarity. But the most important of these was to prevent able bodied young males of one band being lured into another band on the strength of their eligible females. If this process is allowed then constant loosing of effective hunters of the band can bring it to the brink of starvation. Therefore, once again we see that even the birth of such social institutions as family and marriage can also be linked to survival strategy.

Finally we shall consider another complication that arose because of the liberation from rut in our early ancestors. Females develop sexual maturity 3 to 5 years before males. The entering of males into reproductive activity before they are physically strong enough to defend and also fend for subsistence needs of their unit can weaken the structure of the group. Initiation rites seem to have been developed to prevent such weak pairings. The ideological sanction of manhood to the male has to be imparted formally with initiation rites. Consequently more often than not such rites involved the performance of acts of valour or withstanding physical pain. Many of the rock paintings known from Franco-Cantabrian Europe during 18,000 to 10,000 B.C. demonstrate such possibles.

Man has emerged as a well accomplished hunter having a working social system by the time he enters Upper Palaeolithic period. We find changes have often been forced on them because of varieties of factors. It is suggested that such changes can also be viewed within a predictable structure. The prime mover of any change is taken to be population density. A successful adaptation of a population within a chosen ecology can cause rise in population. Technological or economic intensification alone can keep the population fed. It has been observed that mere increase in subsistence can create problem in social control. Thus, society has to increasingly become complex to organize distribution of additional food obtained through intensive technology. The relationship of these three factors can be best represented by the following triangle:

This triangular relationship breaks when population density exceeds the carrying capacity of the chosen ecology. At this point fission occurs in the population and the fissioned group moves to a new ecology. Here a fresh triangular relationship emerges again.