Subsistence patterns of prehistoric coastal California : investigating variations of early maritime adaptation

• Main Author: Porcasi, Judith F.
• Published: University of Leicester 2007
• Subjects: 930.1
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490852

An expansive spatio-temporal approach is used to pattern variations in exploitation of faunal resources at 14 mainland coastal, island, and pericoastal sites with occupations spanning nearly 10,000 years. These sites are arrayed along 500 miles (6 degrees of latitude) of the Central and Southern California coast. An allometric method for estimating faunal biomass is used along with chronological sequences of abundance indices to explore the nature ofthe initial maritime adaptation to the West Coast ofNorth America and changes to this economic strategy over time. Data reveal that throughout prehistorY, California's coastal hunter-gatherers obtained the majority oftheir animal protein from large quantities ofmarine shellfish while vertebrate taxa played a lesser role in the diet. Unexpectedly, however, consumption ofall types of animal flesh, especially the chiefresource (shellfish), declined severely over time. This suggests that: (1) non-trivial dietary changes were \videspread along the entire coast and persisted throughout the Holocene; and (2) major lifeway adaptations involving lesser use of animal protein became the norm throughout prehistory as coastal settlements grew and populations expanded. Although several causal theories are discussed, it appears that ecological changes marking the Late PleistoceneIHolocene transition are the likely root ofthe observed dietary changes. Based on these data, the Paleocoastal colonisers ofthe California coast subsisted on a diet rich in animal protein compatible with a Pleistocene environment and were more 'maritime' than later prehistoric groups based 0t:I their more intensive use ofmarine fauna. Post- Paleocoastal populations subsisted on less animal protein in a pattern consistent with the adoption ofa more carbohydrate-focused diet incorporating resources increasingly available in the emergent Holocene and the more southern latitudes. Scenarios presupposing increasingly intensive exploitation ofmarine mammals and fish over time fostered by technological or cultural elaboration are not supported by the dietary data.