Starch granule analysis of bedrock metates in Warner Valley, Oregon

Starch-rich geophytes are a highly-valued food among many human societies. For example, Indigenous people in the northern Great Basin plan social activities around the seasonal foraging of bulbs, roots, and tubers. Despite such obvious dietary and cultural importance, the antiquity of geophyte use in the Great Basin remains difficult to establish. Herbaceous underground storage organs do not preserve well in the archaeological record. Therefore, most studies rely on indirect evidence to infer geophyte consumption by hunter-gatherers during the late Pleistocene/early Holocene.  It has been suggested that bedrock metates found among upland rock art sites in the northern Great Basin reflect seasonal geophyte exploitation over 14,000 years. Our study tests this hypothesis by analyzing starch residue extracted from bedrock metates at three archaeological sites in the uplands of Warner Valley, Oregon. Species of biscuit root (Lomatium) were collected in the field and sampled for starch. Syste...