Costs and benefits in technological decision making under variable conditions: examples from the late Pleistocene in southern Africa

The issue of technological time costs as applied to the manufacture of flaked stone artefacts is considered. Assuming a positive correlation exists between technological cost and improvements in resource capture, it is shown that the viability of costly technologies is constrained by the abundance of resources in a landscape such that more costly technologies would be likely to be pursued in resource-poor landscapes. This outcome mirrors the results of past assessments of ethnographic data concerning the relationship between subsistence risk and technological complexity. These hypothetical and ethnographic models are then compared to archaeological changes in technological costs at three sites occupied through the late Pleistocene in southern Africa. It is shown that while there is agreement in some respects, there are also times where archaeological outcomes differ dramatically from expectations. The results are taken to suggest that while costly technologies are generally pursued under conditions of increasing global cold, peak cold conditions at the height of Marine Isotope Stages 4 and 2 encouraged a reversion to least-cost technological systems. This may reflect a switch in the focus of optimisation from resource return rates to maximisation of early resource acquisition and/or maximisation of number of subsistence encounters