Optimal Linear Estimation (OLE) Modeling Supports Early Holocene (9000–8000 RCYBP) Copper Tool Production in North America

The discovery and development of metal as a tool medium is a topic of global interest. A fundamental research goal involves establishing the timing of human experimentation with naturally occurring copper ore, which is commonly associated with sedentary, agrarian-based societies. However, in North America, there is well-documented millennia-scale exploitation of copper as tool media by small, seasonally mobile hunter-gatherer groups in the western Great Lakes. Archaeologists have suggested that Late Paleoindian groups may have begun using copper as a tool medium almost immediately after they entered the Lake Superior basin. However, only a few radiocarbon dates support such early use of copper. Here, we use optimal linear estimation modeling to infer the origin date for copper tool production in North America. Our results show that the invention of copper as a tool media likely occurred shortly after the first pioneering populations encountered copper ore during the Pleistocene-Holocene transition. The origin dates modeled here (ca. 8100 RCYBP) reveal several important features about the behavior of pioneering hunter-gatherer populations. Moreover, our results suggest that this phenomenon represents the earliest known use of metal for utilitarian copper tool production.

New Record of Terminal Pleistocene Elk/Wapiti (Cervus canadensis) from Ohio, USA

The earliest appearance of elk/wapiti (Cervus canadensis) in eastern North America is not thoroughly documented due to the small number of directly dated remains. Until recently, no absolute dates on elk bone older than 10,000 14C yr BP (11,621 to 11,306 calibrated years (cal yr) BP) were known from this region. The partial skeleton of the Tope Elk was discovered in 2017 during commercial excavation of peat deposits from a small bog in southeastern Medina County, Ohio, United States. Subsequent examination of the remains revealed the individual to be a robust male approximately 8.5 years old at death. The large size of this individual is compared with late Holocene specimens and suggests diminution of elk since the late Pleistocene. Two accelerator mass spectrometry (AMS) radiocarbon assays on bone collagen samples taken from the scapula and metacarpal of this individual returned ages of 10,270 ± 30 14C yr BP (Beta-477478) (12,154 to 11,835 cal yr BP) and 10,260 ± 30 14C yr BP (Beta-521748) (12,144 to 11,830 cal yr BP), respectively. These results place Cervus canadensis in the terminal Pleistocene of the eastern woodlands and near the establishment of the mixed deciduous forest biome over much of the region. This early temporal placement also situates this early elk as closely following the last representatives of now-extinct megafauna such as the American mastodon (Mammut americanum) and contemporary with the Late Paleoindian inhabitants of the region.

Lawn Lake, a high montane hunting camp in the Colorado (USA) rocky mountains: Insights into early Holocene Late Paleoindian hunter-gatherer adaptations and paleo-landscapes

The Lawn Lake site is a stratified hunting camp situated on a glacial lake outlet river terrace in Rocky Mountain National Park’s upper subalpine forest zone. Its archaeological assemblage represents 9,000 years of hunter-gatherer use as a summer game and plant processing camp for subalpine forest and nearby alpine tundra resource areas. This article’s focus is on the site’s earliest camp levels which contain artifacts and AMS radiocarbon dated hearth charcoal between 8,900 and 7,900 cal yr BP, placing them among the region’s earliest high montane (3,353 m ASL) Paleoindian hunting camps, once part of a network of such sites designed to support systematic high altitude procurement of summer migratory game animals and plant foods in Southern Rocky Mountain subalpine forest and tundra ecosystems. Lawn Lake paleoclimate and paleoecology studies produced long-term pollen records and climate-proxy sediment data for modeling the site’s prehistoric climate and ecology history, useful for interpreting its high-altitude Late Paleoindian hunter-gatherer adaptations.

Cody Complex foragers and their use of grooved abraders in Great Plains and Rocky Mountains of North America

Comparison of Late Paleoindian sites of the Great Plains and Rocky Mountains reveals 36 site components from 28 sites containing ground stone tools, including nine Cody Complex examples. Much of the ground stone use appears related to generalized activity, as few items have functionally specific forms. However, the Cody components have an unexpectedly higher number of grooved abraders as compared to other complexes. We note that Paleoindian examples contain wider u-shaped grooves compared to Late Prehistoric/Protohistoric abraders related to arrow production. We argue that Paleoindian abraders represent shaft abraders, used in the production of dart shafts within weaponry systems. We propose several hypotheses for the emergence of this technology during Cody times. The most parsimonious explanation is that the specific sites containing these abraders represent large camps, occupied for long periods and containing diverse chipped and ground stone assemblages.