Portuguese Teeth and Skeletal Pathologies – the Agricultural Revolution and the Metaphysics of Decline

Studies of contemporary hunter-gatherers as they transition from traditional to modern lifestyles reveal a marked reduction in their health and in the nutritional adequacy of their newly acquired diets.  In addition to studies on extant populations, in the last few decades there is an increasingly sophisticated understanding of how environmental stressors and limited resources translates into pathologies detectable in ancient bones.  This has led to an especially interesting range of investigations by archeologists on populations before and after the Agricultural Revolution starting over 10,000 years ago.  Studies on the recently settled and on old bones may answer the perplexing question of why after the seeming ecological stability of the ancient human lifestyles (lasting, after all, from 200,000 to a mere 10,000 years ago) did the transition from hunter-gatherer modes of existence to an agricultural lifestyle occur at all?

Trugernanner (1812–1876)

The diet of Australian Aborigines has been reasonably well studied.  The modern self-selected diet of Australian aborigines reflects that of the cattle stations where many lived after the colonization of Australia by White pastoralists.[i]  Accompanying these dietary changes were disimprovements in Aborigine’s health – increased prevalence of hypertension, diabetes, and heart disease in adults was noted, as were low child birth weights, and increased childhood morbidity.  

The traditional diet for aboriginal Ngatatjara people, for instance, in the Western Desert was primarily vegetarian supplemented with small game; hunting was largely unsuccessful despite the effort.  Station diets consisted of flour, meat, sugar (usually consumed in tea) and powdered milk.  There was very little fresh fruit and vegetables, milk, cheese, and butter, though individuals supplemented their diets with “bush tucker” and with purchases from neighboring towns.  Ironically, the food at the stations may have reflected the food priorities of hunter-gathers with the ready availability of meat.  However, in the absence of other food items and the increasingly sedentary nature of their lifestyles and the “emotional stresses associated with dispossession” resulted in declining health.[ii] 

A contemporary model of social evolution: an ecological conception of change in the context of the political economy. Johnson and Earle (2000)

Human social arrangements run the gamut from those groups who live largely without the domestication of plants and animals, like the !Kung of the Kalihari Desert, to the global societies of today, heirs, for better or worse, to the consequences of the agricultural, urban and industrial revolutions.  In a previous post I outline an approach developed by Julian Steward to explaining factors driving social evolution and producing this variety of social arrangements.  Julian Steward’s approach to social evolution had the virtue, according to Johnson and Earle, of providing a bridge between social evolutionism and economic anthropology.[i]  The intention of Johnson and Earle's approach is to reconcile “the structural Marxist emphasis of power and the control of resources into a larger, more ecological conception of the political economy as a set of solutions to problems arising in the subsistence economy.”[ii]  Of course contradictions emerge for people between satisfying ecological needs and contribution to political economies.  From an evolutionary perspective social change occurs, say Johnson and Earle, if the benefits to individuals or families participating in new arrangements exceed the cost of participating (assuming, one must suppose, the absence of extreme forms of coercion).  As population density increases, cooperation and group action is inevitability required to solve problems associated with that increase.  Those groups that form “outliers” from the centre of power are those that are outside the “benefit structure” of the political economy.