Flake scar patterns of Clovis points analyzed with a new digital morphometrics approach: evidence for direct transmission of technological knowledge across early North America

Clovis points are the principal diagnostic artifacts of a Clovis complex that spread across North America between ca. 11,050–10,800 radiocarbon years before present. Clovis may be the best documented Paleoamerican culture in North America, but much remains to be learned about the movement and interactions of Clovis peoples. Similarities among Clovis points from geographically diverse locations have led some researchers to suggest that a uniform projectile point technology existed across North America during Clovis times. Others have rejected this idea, proposing local and independent technological adaptations to different regional environments. To investigate these ideas, we used digital morphometrics to analyze 50 Clovis points from nine different contexts. First, 3D surface models of the points were created with a portable laser scanner. Next, these models were digitally cross-sectioned through both faces, yielding two-dimensional isoheight contours of flake scar patterns that reflect the original reduction techniques used to shape the projectile points. In the final step, the contours were transformed with elliptic Fourier analysis into Fourier coefficient series, and patterns of variation and symmetry were explored with principal components analysis. When compared to modern Clovis point replicas made by an expert knapper, the flake scar contours of the ancient Clovis points showed little morphological variation and a large degree of bifacial symmetry. Our results support the existence of a widespread standardized “Clovis” knapping technique, most likely transmitted through direct interaction between knappers from different groups.     

The northern fluted point complex: technological and morphological evidence of adaptation and risk in the late Pleistocene-early Holocene Arctic

Analyses of fluted point technology and Paleoindian technological risk have contributed to our understanding of human adaptation across North America in the late Pleistocene and early Holocene. However, poor chronological control has dissuaded similar studies of fluted points found in Alaska and northern Yukon and our understanding of their adaptive role in early arctic adaptations remains unclear. Two new archeological sites have provided reliable radiocarbon data and for the first time, a comprehensive analysis of northern fluted points is possible. Here, technological and morphological analyses of northern fluted points are presented, including variables statistically evaluated and compared to a collection of fluted Folsom artifacts serving as a reference. Variation in tool shape was measured using geometric morphometrics, and a new approach to landmark placement designed to characterize basal morphology and allow the analysis to include tool fragments is presented. Results confirm that northern fluted points represent a cohesive technological strategy and are used to formulate hypotheses suggesting its service as a risk-management system promoting ease-of-replacement-after-failure to offset transport costs and reduce risk during long-distance travel.     

Why Are Clovis Fluted Points More Resilient than Non‐Fluted Lanceolate Points? A Quantitative Assessment of Breakage Patterns Between Experimental Models

For decades, archaeologists have wondered whether the Clovis Palaeoindian (c.11 600–10 800 radiocarbon years bp ) practice of ‘fluting’, a flake removal technique that creates a distinctive shallow channel extending from the base of the projectile point towards the tip, bestowed a functional advantage over non‐fluted projectile points. Using analytical modelling and static engineering experiments, Thomas et al. (2017) found that points that more effectively redistribute stress and relocate damage can absorb significantly more energy, last longer and remain intact relative to points that do not experience these phenomena. In general, stress redistribution and damage relocation is significantly more likely to occur in fluted points, as opposed to non‐fluted points, suggesting that fluting acts as a ‘shock absorber’. Here, we present a comparative quantitative assessment of breakage patterns between Thomas et al.’s (2017) experimental points that shows those experiencing stress redistribution and damage relocation were also able to significantly better resist breakage, and to incur non‐catastrophic breaks, than points that less effectively redistribute stress and relocate damage. This more beneficial breakage pattern explains the material advantages provided by stress redistribution and damage relocation, and hence the potential motivation for fluting. This does not preclude the possibility that the process of fluting was accorded significance beyond its possible utilitarian value. Additional tests will be necessary to further resolve the ‘shock‐absorbing’ capabilities of fluting.     

Phenetics,cladistics, and the search for the Alaskan ancestors of the Paleoindians: a reassessment of relationships among the Clovis,Nenana, and Denali archaeological complexes

Clovis, Nenana, and Denali are the earliest well-documented archaeological complexes in the New World. Clovis has been found at sites throughout the lower 48 states of the USA and in parts of Canada but not in Alaska, whereas Nenana and Denali have been found in Alaska but not elsewhere in North America. In 1991, Goebel and colleagues reported phenetic analyses of tool types from Clovis, Nenana, and Denali. They found that Nenana clustered more closely with Clovis than with Denali, and concluded from this that Nenana was likely ancestral to Clovis. Goebel et al.'s study has been cited frequently since it was published, and their conclusions have been widely accepted. Here we explain why analyses of the type performed by Goebel et al. are problematic and also demonstrate empirically that their results are dependent on the algorithm and distance measure used. We then reanalyze their dataset with a technique from biology called cladistics. Cladistics has replaced phenetics as the method of choice for reconstructing evolutionary relationships in biology, because it is more objective. The results of this analysis differ from those obtained by Goebel and colleagues. The results strongly suggest that Denali and Clovis are in fact more closely related to each other than either is to Nenana.     

Clovis Lithic Technology: The Devil Is in the Details

Clovis is the best known early development in North America buts its lithic technology is poorly documented and often from animal kill sites. This evidence has been used to picture Clovis peoples as mobile, colonizing, big-game hunters and explanations of lithic technological practices have been framed largely in materialist terms. Increasing documentation suggests views about how the complex Clovis biface and blade production strategies relate to subsistence, land use, and specific kinds of mobility patterns are questionable and often difficult to test with archaeological data. We need to seriously consider the role of Clovis people's worldview in structuring their thought and technical actions.     

Refuting the technological cornerstone of the Ice-Age Atlantic crossing hypothesis

The “North Atlantic Ice-Edge Corridor” hypothesis proposes that sometime during the Last Glacial Maximum, roughly 26,500–19,000 years ago, human populations from southern France and the Iberian Peninsula made their way across the North Atlantic and colonized North America. A key element of that hypothesis is the apparent similarity between stone-tool-production techniques of Solutrean peoples of Western Europe and Clovis and purportedly pre-Clovis peoples of eastern North America, most especially the supposed intentional use of “controlled overshot flaking,” a technique for thinning a bifacial stone tool during manufacture. Overshot flakes, struck from prepared edges of the tool, travel across the face and remove part of the opposite margin. Experimental and archaeological data demonstrate, however, that the most parsimonious explanation for the production of overshot flakes is that they are accidental products created incidentally and inconsistently as knappers attempt to thin bifaces. Thus, instead of representing historical divergence, overshot flakes in Clovis and Solutrean assemblages mark convergence in the use of the same simple solution for thinning bifaces that produced analogous detritus.     

Clovis Hunting and Large Mammal Extinction: A Critical Review of the Evidence

The North American archaeological phenomenon known as Clovis is famous for the fact that a number of sites that contain diagnostic Clovis artifacts also contain the remains of mammoth and perhaps other extinct genera. In the past, this has led many to assume that Clovis subsistence adaptations were organized around large, now-extinct mammals. It has also seemed to support the argument that the colonization of the Americas by hunters about 11,500 years ago caused the extinction, either directly or indirectly, of some 35 genera of primarily large mammals. Here, we review all sites known to us that have been suggested to provide evidence for the association of Clovis-age archaeological material with the remains of now-extinct Pleistocene mammals. Of the 76 sites reviewed, only 14 provide strong evidence that Clovis-aged people hunted such mammals. Of these sites, 12 contain the remains of mammoth, while two contain the remains of mastodon. Although the prime focus of the analysis we present is on Clovis-age archaeological associations with now-extinct mammals, we conclude that there is no evidence provided by the North American archaeological record to support the argument that people played a significant role in causing Pleistocene extinctions here.     

Quantification of Fracture Propagation Velocity Employing a Sample of Clovis Channel Flakes

Velocity-dependant lithic fracture surface features are employed to determine precursory loading rate. The methodology is applied to a sample of Clovis channel-flake scars revealing that some Clovis points were fluted using pressure-flaking techniques.     

A Model for Paleoamerican Coastal Zone Preference for the Atlantic Slope of Eastern North America Since the Last Glacial Maximum

Paleoamerican colonization models have emphasized the importance of coastal zones for provisioning hunter gatherers with a diverse range of subsistence resources. This article expands on recent research by Lowery et al. 2012, and presents a model to explain the distribution of Clovis points across the Atlantic slope of Eastern North America. Marine transgression since the last glaciation has submerged large tracts of the Atlantic continental shelf. Global bathymetric data was used to estimate the Clovis age shoreline from Delaware to Florida. Clovis biface data for modern coastal areas, obtained from the Paleoindian database of the Americas, was compared to the slope of the paleo-shoreline to predict coastal zone preference. Results indicate a relationship between point distribution and coastal zone type. Areas where major rivers with high-quality tool-stone intersect broad coastal zones served important roles to Clovis subsistence adaptations. The potential exists for early Paleoamerican sites along the continental shelf submerged beneath 55–75 m of the Atlantic Ocean. Modern coastal regions with high densities of Clovis points may serve as analogues for identifying earlier sites that have been submerged as a result of marine transgression.     

Anticipated mobility and its archaeological signature: A case study of Folsom retooling strategies

This essay highlights the value of anticipated mobility for untangling variability in prehistoric stone tool manufacture. To do so, it explores the organization of weaponry production at a series of Folsom campsites via the highly visible archaeological signature of Folsom fluting. A model of weaponry replacement based on deep planning and anticipation of needs is proposed, according to which Folsom hunters commonly replace their projectile points as they wear down, break or are lost, but on fewer occasions engage in the mass production of fluted points. This technological organization is consistent with a highly mobile way of life in which advanced planning buffers the risk associated with limited or stochastic access to good quality lithic raw materials. The model is then put to the test at the Lindenmeier site in northern Colorado. The spatial patterning of fluting activities in two discrete areas of the site demonstrates contrasting strategies of point manufacture: conservation versus gearing up (creation of a surplus). It is argued that these patterns represent distinct facets of a single technological organization.     

The accumulation of stochastic copying errors causes drift in culturally transmitted technologies: Quantifying Clovis evolutionary dynamics

The archaeological record is the empirical record of human cultural evolution. By measuring rates of change in archaeological data through time and space it is possible to estimate both the various evolutionary mechanisms that contribute to the generation of archaeological variation, and the social learning rules involved in the transmission of cultural information. Here we show that the recently proposed accumulated copying error model [Eerkens, J.W., Lipo, C.P., 2005. Cultural transmission, copying errors, and the generation of variation in material culture and the archaeological record. Journal of Anthropology archaeology 24, 316–334.] provides a rich, quantitative framework with which to model the cultural transmission of quantitative data. Using analytical arguments, we find that the accumulated copying error model predicts negative drift in quantitative data due to the proportional nature of compounded copying errors (i.e., neutral mutations), and the multiplicative process of cultural transmission. Further, we find that the theoretically predicted rate of drift in long-lived technologies is remarkably close to the observed reduction of Clovis projectile point size through time and space across North America.     

AMS C dating of early human occupation of southern South America

The time of appearance of a persistent and demographically-viable hunter-gatherer population in late Pleistocene southern South America must be determined by evaluating evidence from as large as possible a sample of candidate archaeological sites in the region. We co-ordinated the AMS dating of multiple bone and charcoal samples from previously-excavated strata at the following sites: Arroyo Seco 2, Paso Otero 5, Piedra Museo, and Cueva Tres Tetas (all in Argentina), and Cueva del Lago Sofia 1 and Tres Arroyos (both in Chile). With one possible exception, we did not obtain new results to confirm earlier observations of pre-Clovis-age cultural activity at any of the sites considered in this study. The possible exception, Arroyo Seco 2, is considered in detail elsewhere [Politis G., Gutierrez M.A., Scabuzzo, C. (Eds), in press. Estado actual de las Investigaciones en el sitio 2 de Arroyo Seco (región pampeana, Argentina). Serie Monográfica INCUAPA 5. Olavarría]. However, our results for the samples which were the most preferred indicators of cultural events (hearth charcoal and cut-marked bone) confirm that people were in the southern cone of South America at or soon after 11,000 BP (13,000 cal BP). Considered alongside recent age estimates for the Clovis culture in North America, these results imply the contemporaneous emergence of a consistent and archaeologically-robust human occupation signal at widely-separated locations across the Western Hemisphere. Such findings suggest that Palaeoindian demic expansion may have involved more than one terminal Pleistocene dispersal episode.     

Trace element and Pb isotope provenance analyses of native copper in northwestern North America: results of a recent pilot study using INAA,ICP-MS,and LA-MC-ICP-MS

Several indigenous groups in northwestern North America used native copper prior to EuroAmerican contact. The Arctic, Subarctic, and Northwest Coast culture areas all have archaeological finds and geological sources of native copper. The copper-rich region of south-central Alaska and southwestern Yukon has often been credited as the source of archaeological native copper found on the Northwest Coast despite the presence of native copper sources further south. This paper presents the results of a pilot study using INAA, ICP-MS, and LA-MC-ICP-MS to assess the potential for native copper provenance research in Alaska and the Yukon Territory. Discrete native copper sources could be distinguished from one another intra-regionally. Difficulties associated with future native copper provenance research in northwestern North America are discussed.     

Pattern or bias? A critical evaluation of Midwestern fluted point distributions using raster based GIS

Because the abundance and distribution of fluted points has long played a critical role in interpreting various colonization and settlement scenarios of North America, correlations made between fluted point distribution and patterns of Early Paleoindian land use need to be critically evaluated. Gauging not just the source, but also nature of bias within distributional data of this sort is important if we are to improve the accuracy and reliability of our inferences concerning the timing, source, and mode of the radiation of human populations throughout the western Hemisphere. In this study, I employ a raster based GIS approach using a continuous non-site distribution of fluted biface distributions across a twenty-nine county (46,000 km²) study area of northern Illinois. The results suggest that when sources of bias are revealed and controlled for, significant settlement patterning can not only be identified, but more accurately interpreted.     

Wintering at Little Island Rock: A Fur Trade Site on Grand Island

Abstract

Research conducted by Hiawatha National Forest personnel in 2000–2002 investigated the well-preserved archaeological remains of a circa 1820s fur trader’s wintering post located on Grand Island, near the south shore of Lake Superior. The most likely occupant of this post was Henry A. Levake, a trader from Sault Sainte Marie (St. Mary’s Falls) who was accompanied by his Native American wife. Both archaeological and historical information show that the Little Island Rock Post is an example of a specialized cold-climate adaptation developed in the boreal forests of North America and in the northern portion of the temperate forests to the south. Key elements of this adaptation include: location near a late fall or winter fishery, use of large amounts of clay for chimney construction, and the presence of ample storage facilities, especially pits. Features associated with this adaptation at the Little Island Rock Post also reflect the multiethnic occupational subculture of the fur trade. This site fills a large gap in the known distribution of wintering post archaeological sites across North America.     

A geometric morphometrics-based assessment of blade shape differences among Paleoindian projectile point types from western North America

Blade shape features in the type definitions of Clovis, Folsom, and Plainview projectile points. However, the accuracy of these assessments has never been evaluated. Here we report a study in which geometric morphometrics and multivariate statistics were used to compare the shapes of the blades of Clovis, Folsom and Plainview points from the Southern Plains of North America. In the course of the analyses, we controlled for the impact of three potential confounding factors: allometry, differences in raw material quality, and resharpening. The analyses show that blade shape distinguishes Clovis points from both Folsom points and Plainview points, but does not distinguish Folsom points from Plainview points. The analyses also show that the similarities and differences in blade shape among the types are independent of allometry, raw material quality, and resharpening. These findings suggest that the type definitions for Clovis, Folsom and Plainview need to be altered. They also have implications for typing specimens that lack other defining characters (e.g. channel flakes, flutes). Lastly, the absence of resharpening effects raises questions about the validity of the reduction thesis.     

Continent-wide or region-specific? A geometric morphometrics-based assessment of variation in Clovis point shape

Researchers have debated the existence of regional variation in Clovis points for over 60 years. Here, we report an attempt to resolve this argument using a large sample of Clovis points from dated assemblages and a suite of shape analysis methods known as geometric morphometrics. The study tested the two main hypotheses that have been put forward in the debate: the continent-wide adaptation hypothesis, which holds that Clovis points do not vary regionally, and the regional environmental adaptation hypothesis, which holds that there is regional variation as a consequence of Clovis groups adjusting their food-getting toolkits to local conditions. We used discriminant function analysis and a multivariate extension of the t test to assess whether differences in shape exist at two scales. The first set of analyses compared points from the most obvious environmental regions in North America, the East and the West. The second set of analyses investigated differences among points from subregions within the East and West. The analyses revealed significant differences between points from the East and the West and among points from some subregions. Follow-up analyses demonstrated that these differences are not the result of the most common confounding factors, raw material quality and resharpening. As such, the analyses support the regional environmental adaptation hypothesis rather than the continent-wide adaptation hypothesis. We conclude from this that Clovis people modified their points to suit the characteristics of local prey and/or the habitats in which they hunted.     

Clovis,Folsom, and Midland components at the Debra L. Friedkin site,Texas: context,chronology, and assemblages

The archaeological transition from Clovis to Folsom and Midland in the North American Great Plains coincides with the end of the Pleistocene and onset of the Younger Dryas. Comparisons exploring the adaptive changes that took place during this period frequently employ regional-scale approaches. The focus on regional-scale analyses largely results from the dearth of sites repeatedly visited by multiple early Paleoindian groups. However, regional-scale comparisons have the potential to overlook smaller-scale differences. The Debra L. Friedkin site, Texas offers an opportunity to study Midland, Folsom, and Clovis technology and site-use at a single site. This paper presents the context and chronology of the Midland, Folsom, and Clovis assemblages and a site-scale analysis of lithics from the Friedkin site. It is argued that point production and late-stage reduction were primary activities, and the use of bifacial cores for flake tools was important throughout these occupation periods. Site use at Friedkin differs from early Paleoindian occupation at the nearby Gault site and expands our understanding of settlement and technological organization in the region.     

Context and spatial organization of the Clovis assemblage from the Topper site,South Carolina

Abstract

This paper reports results of a 40 sq m block excavation of the Clovis assemblage from the Topper site, South Carolina. Topper is one of only three buried, extensively excavated Clovis quarry-related sites in North America. The Clovis assemblage was recovered in a buried component distinct from overlying Archaic and Woodland components. The site geomorphology and formation processes and the horizontal distribution of the assemblage are used to identify a workshop floor with discrete knapping loci created by unique production and use goals. The excavated assemblage from Topper provides useful and important information in order to reinterpret the Clovis occupation of the Southeast. Moreover, spatial patterning from Topper shows Clovis people organized and structured onsite activities at quarry-related sites.     

Earliest hunters and gatherers of South America

Traditional syntheses of the archaeology of the late Pleistocene period in South America have focused primarily on the peopling of the continent by North American cultural groups and on identifying associations among regional sites. This focus has tended to ignore the widespread culture diversity of the period and the possible effects of different paleolandscapes on human migration and colonization, such as the presence of unglaciated tropical and temperate environments in the northern lowlands, the gateway to the interior. The earliest known cultural assemblages are characterized by various unifacial and bifacial lithic industries that may represent regional processes reminiscent of an Archaic lifeway. The major archaeological sites and associated artifact assemblages are examined in terms of regional and continental patterns of environmental and cultural change. Results suggest that the Pleistocene archaeological record of South America must be explained in its own terms and that the events and processes producing this record either occurred earlier than previously thought or are very different from those in North America.