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Accueil du site → Doctorat → États-Unis → 2011 → If the Desert Blooms : A Technological Perspective on Paleoindian Ecology in the Great Basin from the Old River Bed, Utah

University of Nevada, Reno (2011)

If the Desert Blooms : A Technological Perspective on Paleoindian Ecology in the Great Basin from the Old River Bed, Utah

Duke, Daron

Titre : If the Desert Blooms : A Technological Perspective on Paleoindian Ecology in the Great Basin from the Old River Bed, Utah

Auteur  : Duke, Daron

Université de soutenance : University of Nevada, Reno

Grade : Doctor of Philosophy (PhD) 2011

The earliest inhabitants of the Great Basin adapted to a well-watered environment that was already set to disappear. This much seems clear from paleoenvironmental data, but a good understanding of how the declining ecosystem affected Paleoindian peoples still eludes us. In the now-barren expanse of the Great Salt Lake Desert, the Old River Bed (ORB) delta existed as a sprawling distributary wetland at the Pleistocene-Holocene transition. At its peak, the system would have been one of the largest marshlands in the Great Basin. Paleoindians visited the distal reaches of the wetlands between about 12,100 and 9900 cal BP, when it finally dried up. My study tracks spatial and temporal variability in lithic technology across the distal ORB to address issues of how people coped with the regionally deteriorating environment. Patterns are compared between the west and east sides of the study area, which roughly date to sequential time frames of 12,100–11,200 cal BP and 11,300–9900 cal BP, respectively, based on dating of buried wetland organics. These subareas correspond with spatially distinct groups of distributary paleochannels. Using a formal technological model, lithic data are examined in terms of reduction strategies, toolstone selection, and morphology as they relate to emphasis on transport efficiency. The results of the analysis show that people were more transport-efficiency conscious earlier in time than they were later. According to the model, this directly relates to occupation length—viewed here as time spent in the basin, not necessarily at a single site—whereby increasing mobility necessitates the need for transport efficiency in order to reduce the risks of not having enough stone on-hand and the costs of having to procure more. When the study subareas are compared, west-subarea assemblages indicate greater emphasis on transport efficiency with streamlined toolkits made more often from obsidian than seen in the east subarea, where fine-grained volcanic (FGV) stone is more common. This strategy placed a buffer of toolstone into relatively large tools that were reduced bifacially through an extended sequence. Parman, Lake Mojave, and Cougar Mountain projectile points tend to be associated with the west subarea and this technological pattern. The technology of the east subarea is "flakier," with smaller tools being made from transported flake blanks following a more local toolstone profile. This strategy shifts costs from the production and maintenance investments of transport efficiency to the transport of stone directly to its location of use. Bonneville and Pinto projectile points tend to be associated with the east subarea and this technological pattern. A second pattern found predominately in east-subarea sites is the extreme economization of obsidian. Various small biface fragments and irregular tools are seen, and the extensively reworked Stubby stemmed type is also more common in this subarea. This reduction pattern signals higher predictability in tool-use requirements and raw material acquisition. These data are interpreted to represent shorter basin occupations earlier and longer basin occupations later in time. Assuming the total ORB delta was more or less always capable of sustaining people for long periods of time while it existed, any shift in settlement mobility should be driven by conditions in the other regional wetlands they visited. Being in such a large drainage basin, the ORB likely persisted while smaller basin wetlands succumbed to Early Holocene drying more rapidly. Thus, I argue that the shift in lithic technology seen on the distal ORB provides a dynamic model for how people responded to regional environmental decline that is currently missing from Paleoindian studies.

Mots Clés : Old River Bed, Utah, Ecology, Great Basin, Hunter-gatherers, Lithic technology, Obsidian hydration dating, Paleoindian

Présentation (PQDT Open)

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Page publiée le 10 mai 2012, mise à jour le 25 septembre 2017