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Sex estimation of skeletons is fundamental to many archaeological studies. Currently, three approaches are available to estimate sex-osteology, genomics, or proteomics, but little is known about the relative reliability of these methods in applied settings. We present matching osteological, shotgun-genomic, and proteomic data to estimate the sex of 55 individuals, each with an independent radiocarbon date between 2,440 and 100 cal BP, from two ancestral Ohlone sites in Central California. Sex estimation was possible in 100% of this burial sample using proteomics, in 91% using genomics, and in 51% using osteology. Agreement between the methods was high, however conflicts did occur. Genomic sex estimates were 100% consistent with proteomic and osteological estimates when DNA reads were above 100,000 total sequences. However, more than half the samples had DNA read numbers below this threshold, producing high rates of conflict with osteological and proteomic data where nine out of twenty conditional DNA sex estimates conflicted with proteomics. While the DNA signal decreased by an order of magnitude in the older burial samples, there was no decrease in proteomic signal. We conclude that proteomics provides an important complement to osteological and shotgun-genomic sex estimation.

Sex estimation of skeletons is fundamental to many archaeological studies. Currently, three approaches are available to estimate sex-osteology, genomics, or proteomics, but little is known about the relative reliability of these methods in applied settings. We present matching osteological, shotgun-genomic, and proteomic data to estimate the sex of 55 individuals, each with an independent radiocarbon date between 2,440 and 100 cal BP, from two ancestral Ohlone sites in Central California. Sex estimation was possible in 100% of this burial sample using proteomics, in 91% using genomics, and in 51% using osteology. Agreement between the methods was high, however conflicts did occur. Genomic sex estimates were 100% consistent with proteomic and osteological estimates when DNA reads were above 100,000 total sequences. However, more than half the samples had DNA read numbers below this threshold, producing high rates of conflict with osteological and proteomic data where nine out of twenty conditional DNA sex estimates conflicted with proteomics. While the DNA signal decreased by an order of magnitude in the older burial samples, there was no decrease in proteomic signal. We conclude that proteomics provides an important complement to osteological and shotgun-genomic sex estimation.

This paper takes a geoarchaeological contextual approach in arguing that pavement quarries—those assay and reduction events directed at cobbles that often litter expansive desert alluvial landforms—can provide a powerful index of changing trans-Holocene settlement organization. Focusing on multiple lines of evidence—age estimates of alluvial fan surfaces, quarry technology, patination pro les, and regional toolstone consumption trends at residential sites—we explore the temporal and technological development of quarry pavement use at the National Training Center at Fort Irwin, Mojave Desert. The analysis reveals that chert pavement quarrying was in ascendance during the early portion of the Late Holocene and had a strong biface production component. This landform-based model of Holocene pavement quarry development provides support for reconstructions that envision Gypsum period hunter-gatherers as residentially stable, and as undertaking increased logistical forays during which pavement quarry procurement took place.

For some time, an interpretation of coastal occupation in the San Diego area of southern California, herein termed the Coastal Decline Model, has held center stage despite limited and patchy empirical data. This reconstruction, based largely on the Batiquitos Lagoon fieldwork of the 1960s to 1980s, posits a major depopulation of the coast during the Late Holocene as estuarine subsistence productivity declined under the impact of rapid siltation. Recent investigations at nine shell midden sites along the coast of Camp Pendleton Marine Corps Base in the northern portion of this region challenge prior inferences. In this area, emerging trends in settlement and subsistence strategies suggest critical shifts took place during the Middle to Late Holocene. Specifically, three new results contradict key test implications of the Coastal Decline Model: (1) numerous coastal sites are now dated to the Late Holocene when marine transgression is thought to have "shut down" extensive coastal occupation; (2) Late Holocene sites are not typically smaller and/or more reflective of short-term or single season occupation than earlier sites; and (3) shellfish remain important to the coastal economy throughout the Holocene. It is argued that resource intensification played a major role in the continued occupation of this portion of coastal southern California.