The three lives of a uniface
Graphical abstract
Introduction
The transition from Clovis to later-Paleoindian cultures is an important phase in the broader Peopling of North America. While valid and important debates remain about the existence and nature of a “pre-Clovis” or “earlier-than-Clovis” presence in North America (e.g. Haynes et al., 2007, Waguespack and Kelly, 2014, Morrow et al., 2012, Redmond et al., 2012, Waters and Stafford, 2007, Waters et al., 2011), current evidence suggests the rapid and widespread geographic expansion of Clovis populations is reasonably interpreted to be a colonizing movement into unfamiliar territory (Anderson, 1995, Ellis, 2008, Hamilton and Buchanan, 2007, Haynes, 2002, Meltzer, 2002, Meltzer, 2004, Meltzer, 2009, Kelly, 1999, Kelly, 2003). Even if pre-Clovis populations are shown to be present in North America, there is no evidence to suggest that their populations were anything but sparse. Therefore, in the event that Clovis was a “subsequent” group spreading throughout the continent, it appears that their access to large areas of North America was essentially unrestricted (Meltzer, 2002:31). As such, on a continental scale Clovis (ca. 13,500 calendar years before present [calBP] to 12,800 calBP [Holliday, 2000, Waters and Stafford, 2007]) can certainly be considered “more closely tied to the colonization process” (Ellis, 2011:387) than post-Clovis cultures. By definition, this means that colonizing Clovis groups were still in the process of exploring the North American Pleistocene landscape, and learning about its habitats and resources. Alternatively, temporally later post-Clovis Paleoindians, while in specific instances perhaps still colonizing new landscapes (e.g. the newly opened Ice-Free corridor, Meltzer, 2009:303–306), on the whole appear to have been “settling-in” and “filling-in” particular regions (Meltzer, 2009:286; Walthall, 1998; see also papers in Bousman and Vierra, 2012). Relative to Clovis Paleoindians, post-Clovis Paleoindians possessed a higher degree of landscape familiarity (Rockman and Steele, 2003) – a characteristic that had archaeologically visible effects on mobility, subsistence, social structure, and lithic technology.
These broad characterizations of Clovis and post-Clovis cultural adaptations arise from several converging and interrelated lines of evidence. In general, the transition to immediate post-Clovis Paleoindian ways of life marks the beginning of the behavioral changes documented in the larger pan-continental Paleoindian to Archaic transition (e.g. Bousman and Vierra, 2012, Anderson and Sassaman, 1996). A good deal of attention has been paid to this process in many of the major regions of North America (e.g., Eastern North America [Anderson, 1996, Ellis et al., 1998, Driskell et al., 2012, Carr and Adovasio, 2012], the Great Plains and Rocky Mountains [Bousman and Oksanen, 2012, Kornfeld and Larson, 2008, Larson, 2012], and the Great Basin [Madsen, 2007, Jones and Beck, 2012]). The broad consensus in most places is that there is a shift toward a more generalized subsistence pattern, though the degree to which this occurred varied by habitat (Amick, 1994; Hill, 2007, Hill, 2008, Hill and Knell, 2013, Knell and Hill, 2012). This shift is also associated with changes in mobility and settlement, which is reduced and more bounded in some habitats (see Amick, 1994, Hill and Knell, 2013, Knell, 2013, Knell and Hill, 2012), and in technology the shift is toward more expedient production and organization. This transition is thought to be driven by both environmental changes at the beginning of the Holocene and demographic changes resulting from increased “packing” of regionally restricted populations (Bamforth, 1997, Binford, 2001:442–443), which ultimately facilitated increased landscape familiarity. Though often viewed as a large-scale general transition, the timing, sequence, and nature of these changes are of course region and habitat specific (Bousman et al., 2002; papers in Bousman and Vierra, 2012).
One of the most well-known and archaeologically visible outcomes of these changes was the veritable explosion of regional projectile point styles. This process was already underway during the Clovis period (Buchanan et al., 2014, Smallwood, 2012, Smith et al., 2014), but becomes more apparent in the immediate post-Clovis record with the appearance of variants like Folsom, Parkhill, Dalton, Great Basin Stemmed, and a variety of other “middle” Paleoindian point styles (e.g. Bousman and Vierra, 2012, O'Brien et al., 2014, Thulman, 2006). The pattern is even more pronounced by the late Paleoindian period when dozens (if not hundreds) of regional styles are recognized. This growth in cultural diversity, as evidenced by point “style”, has been explained by invoking two non-mutually exclusive factors tied to increased landscape familiarity (e.g. Meltzer, 2009:286; O'Brien et al., 2014). First, there were perhaps function- or environment-specific adaptive changes to stone point technology as hunter–gatherer groups grew more familiar with their landscape in terms of the subsistence base and location of dependable stone raw materials. Second, technological drift occurred as post-Clovis Paleoindians faced less pressure to “maintain contact with distant kin” during “a steady settling-in and filling-in of the landscape” (Meltzer, 2009:286).
Here we examine whether the broadly defined class of items known as “unifacial stone tools” was also influenced substantially by the differential landscape familiarity of colonizing versus non-colonizing foragers. Much of the Paleoindian unifacial stone tool class is comprised of what archaeologists usually refer to as “endscrapers”, but it also includes artifacts archaeologists would label as “sidescrapers”, “retouched flakes”, “gravers”, among others (e.g. “spokeshaves”). Despite the inference that unifacial stone tools, such as endscrapers, were likely “style-free” (Meltzer, 1981), there are good reasons to suspect a link between landscape familiarity and unifacial tool technological organization. Colonizers would at first be unfamiliar with a new landscape's stone raw material sources, and the presumed lower population density make it less likely that this information could be immediately learned through social interaction (Shennan, 2000, Shennan, 2001, Henrich, 2004). Alternatively, non-colonizing populations, having been on the landscape for centuries were not faced with the same degree of uncertainty with respect to stone raw material source locations. Thus, unifacial tool design, production, transport, and maintenance costs and benefits were likely assessed differently between colonizers and non-colonizers, especially given that a broad class such as unifacial tools was often the majority component of Paleoindian assemblages and very likely important to technological considerations (Bamforth, 2009, Surovell, 2009).
From a colonizer's perspective, unifacial stone tools (on the population level) should possess the design property of longevity, such that they can be “carefully maintained, resharpened, and recycled”, because as “groups looped around the landscape […] and their stone supply dwindled” (Meltzer, 2002:37) colonizers could not be certain of encountering new stone outcrops to replenish their stock. From a non-colonizer's perspective, however, the design property of longevity would be less important. Why design tools (again, on the population level) for longevity – or, for that matter, carry unifacial stone tools at all – when one knows where stone outcrops are located and can easily schedule trips to them during seasonal rounds? It would make more sense to design task-specific tools (Bleed, 1986), or, given that unifacial stone tools are relatively easy to knap, quickly make them from the local stone outcrop nearby the band's next stop on the landscape. Of course, none of this is to say that all colonizers are “lost” on the landscape and all non-colonizers have perfect knowledge of their surroundings. But on the population level it seems reasonable to hypothesize that, in spite of population variability, colonizers and non-colonizers would approach and exploit the tool design property of longevity differently.
Toward this end, Eren (2013) recently showed that a statistically significant allometric relationship exists between the size and shape of Clovis unifacial stone tools that was consistent with the hypothesis that Clovis colonizing foragers in the North American Lower Great Lakes region selected unifacial stone tool blanks for the design property of longevity and then exploited that property (Fig. 1, Fig. 2, red trendline). Larger, and presumably less resharpened,1 tools possessed flatter, less spherical shapes than the smaller, and presumably more resharpened, tools which possessed more globular, spherical shapes, suggesting Clovis foragers exploited the retouch potential afforded by the larger, flatter blanks (Eren, 2013:2107; see Turq, 1992, Kuhn, 1994, Eren and Lycett, 2012, Surovell, 2009). Geometrically, this allometric pattern arises because unifacial stone tool thickness would have been minimally effected by resharpening (Blades, 2003, Goodyear, 1979, Morrow, 1997, Patten, 2005, Shott and Seeman, 2014, Shott and Weedman, 2007, Surovell, 2009) relative to plan-view surface area (i.e. length × width). Therefore, as unifacial resharpening proceeds, thickness plays an increasingly significant role in a tool's shape as the length and width variables approach the thickness value.
While the Clovis “longevity pattern” depicted in Fig. 1 suggests that on the population level longevity was a design property Clovis foragers selected for in their unifacial tools, it remains unclear whether this pattern is unique to foragers tied closely to the colonization process, or whether all foragers' unifacial tools would exhibit this pattern. In other words, in order to avoid approaching the concepts of “longevity” and “retouch potential” as merely unspecified measurements or non-specific generalizations, it is important to assess the Clovis pattern against a comparative standard (Clarke, 1968:28). Therefore, our goal here is to compare the Great Lakes colonizing Clovis unifacial tool dataset and its allometric pattern (Eren, 2013, Fig. 1) against that of non-colonizing, post-Clovis foragers. Following our discussion from above, we hypothesized that the design property of longevity would not have been as important to post-Clovis non-colonizing foragers as it was to their Clovis colonizing ancestors. This is because post-Clovis foragers would have been more familiar with their relatively smaller environments and thus would have known where local stone outcrops were located, and were able to better tailor their unifacial tools to habitat-specific functional and scheduling requirements.
Schematically, the Clovis unifacial stone tool “longevity pattern” is represented by the red inverse trendline in Fig. 2. If, as hypothesized, post-Clovis foragers were less concerned with the property of longevity in their unifacial stone tools than Clovis foragers, then we can predict that the allometric pattern of post-Clovis unifacial stone tools will yield a significantly less steep slope than the Clovis pattern, or perhaps even no relationship at all (Fig. 2, blue trendline). A third alternative is that the largest unifacial stone tools are rounder than the smallest stone tools. In the current analysis this pattern would result in a positive trendline (Fig. 2, green trendline). Given that it is mechanically and geometrically impossible for a unifacial stone tool to become relatively flatter via unifacial retouch (Fig. 3), this third alternative would suggest that post-Clovis Paleoindians were not concerned with the design property and exploitation of longevity with respect to their unifacial stone tool component. This pattern could arise, for example, because: (1) post-Clovis unifacial stone tools were more likely to be expediently retouched implements; and/or (2) specific post-Clovis functional activities were facilitated by large unifacial tools possessing rounder shapes and/or small unifacial tools possessing flatter shapes. Whatever the reason(s), given the mechanics and geometry of unifacial retouch, this third result would suggest that larger unifacial tools were not being resharpened or recycled into smaller unifacial tools.
Section snippets
Samples
Our analyses were on 435 unbroken unifacial stone tools from several post-Clovis Paleoindian sites. Specimens broadly conformed to the explicit definition of “unifacial stone tools” following Eren et al. (2012). Data on 146 unifacial stone tools were available from Ellis and Deller (2000) and Ellis (1984), respectively, from the Parkhill and Thedford II sites. These sites contribute to the Parkhill Paleoindian Phase of the Lower Great Lakes region, which is characterized by “Barnes” style
Results
Fig. 5 shows the post-Clovis unifacial stone tool size data plotted against the shape data. There is a statistically significant correlation (Spearman's Rho = 0.142, [2-Tailed] p = 0.003). This result is consistent with the green trendline of the allometric model presented in Fig. 5 and suggests that, on the population level, post-Clovis Paleoindians were not concerned with the design property of longevity with respect to their unifacial stone tools.3
Discussion
Binford and Qiumby (1972:454) asked, “Why is it that endscrapers as a class exhibit relatively little variability either spatially or temporally compared to projectile points or some other class of item?” If the reader will indulge us and allow for the replacement of the term “endscraper” with the broader and explicitly defined class of “unifacial stone tools”, then our results suggest that Binford's assumption is incorrect: unifacial stone tools exhibit tremendous variability both spatially
Acknowledgments
This manuscript's title was inspired by the 1988 article in American Antiquity “The Three Sides of a Biface” by Robert Kelly, who graciously allowed us to rip it off. The following institutions and people facilitated the data recording: the Cleveland Museum of Natural History, University of Michigan Museum of Anthropology in Ann Arbor, the New York State Museum in Albany, the Royal Ontario Museum in Toronto, Adrienne Desjardine, Ann DuFresne, Mike Gramly, Jon Lothrop, Karen O'Brien, Brian
References (118)
- et al.
Variability in bifacial technology at Elandsfontein, Western cape, South Africa: a geometric morphometric approach
J. Archaeol. Sci.
(2010) Projectile points, people, and plains Paleoindian perambulations
J. Anthropol. Archaeol.
(2009)- et al.
Neutron activation analysis of 12,900-year-old stone artifacts confirms 450–510+ km Clovis tool-stone acquisition at Paleo Crossing (33ME274), northeast Ohio, USA
J. Archaeol. Sci.
(2015) - et al.
A geometric morphometrics-based assessment of blade shape differences among Paleoindian projectile point types from western North America
J. Archaeol. Sci.
(2010) An index of invasiveness for the measurement of unifacial and bifacial retouch: a theoretical, experimental and archaeological verification
J. Archaeol. Sci.
(2002)- et al.
Estimating original flake mass from 3D scans of platform area
J. Archaeol. Sci.
(2011) - et al.
Spatiotemporal dynamics of the Clovis–Folsom transition
J. Archaeol. Sci.
(2010) - et al.
The effect of hammer mass and velocity on flake mass
J. Archaeol. Sci.
(1995) The fluted point tradition and the Arctic small tool tradition: what's the connection?
J. Anthropol. Archaeol.
(2008)Measuring Paleoindian range mobility and land-use in the Great Lakes/Northeast
J. Anthropol. Archaeol.
(2011)
Archaeology of the Pleistocene–Holocene transition in Eastern North America
Quat. Int.
The Younger Dryas and Late Pleistocene peoples of the Great Lakes region
Quat. Int.
The technology of stone age colonization: an empirical, regional-scale examination of Clovis unifacial stone tool reduction, allometry, and edge angle from the North American Lower Great Lakes region
J. Archaeol. Sci.
Defining and measuring reduction in unifacial scrapers
J. Archaeol. Sci.
The role of raw material differences in stone tool shape variation: an experimental assessment
J. Archaeol. Sci.
Variation in Paleoindian fauna use on the Great Plains and Rocky Mountains of North America
Quat. Int.
Experimental evaluation of Kuhn's geometric index of reduction and the flat-flake problem
J. Archaeol. Sci.
The handaxe reloaded: a morphometric reassessment of Acheulian and Middle Paleolithic handaxes
J. Hum. Evol.
A biface and blade core efficiency experiment: implications for Early Paleoindian technological organization
J. Archaeol. Sci.
Maybe we do know people first came to North America; and what does it mean if we do?
Quat. Int.
Bonebeds and other myths: Paleoindian to Archaic transition on the North American Great Plains and Rocky Mountains
Quat. Int.
A geometric index of reduction for unifacial stone tools
J. Archaeol. Sci.
Paleoindians and the Younger Dryas in the New England-Maritimes region
Quat. Int.
A crossbeam co-ordinate caliper for the morphometric analysis of lithic nuclei: a description, text, and empirical examples of application
J. Archaeol. Sci.
Technological behaviors in Paleolithic foragers. Testing the role of resharpening in the assemblage organization
J. Archaeol. Sci.
Pre-Clovis in Texas? A critical assessment of the “Buttermilk Creek Complex”
J. Archaeol. Sci.
Innovation and cultural transmission in the American Paleolithic: phylogenetic analysis of eastern Paleoindian projectile-point classes
J. Anthropol. Archaeol.
Folsom Diet Breadth and Land Use in the American Southwest
Recent advances in Paleoindian and Archaic period research in the southeastern United States
Archaeol. East. N. Am.
Models of Paleoindian and Early Archaic settlement in the Lower Southeast
Folsom Adaptive Systems in the Upper Gunnison Basin, Colorado: an Analysis of the Mountaineer Site
Adaptive change on the Great Plains at the Paleoindian/Archaic transition
An Archaeological Perspective
Constructing Frames of Reference
End scraper reduction and hunter–gatherer mobility
Am. Antiq.
The optimal design of hunting weapons: maintainability or reliability
Am. Antiq.
The Protoarchaic in Central Texas and surrounding areas
The Palaeoindian-Archaic transition in North America: new evidence from Texas
Antiquity
Quantifying variation in landscape-scale behaviors: the Oldowan of Koobi Fora
Archaeological investigations at the Paleo Crossing Site, a Paleo-Indian occupation in Medina County, Ohio
An assessment of the impact of resharpening on Paleoindian projectile point blade shape using geometric morphometric techniques
A morphometric assessment of the intended function of cached Clovis points
PLoS One
Continent-wide or region-specific? A geometric morphometrics-based assessment of variation in Clovis point shape
Archaeol. Anthropol. Sci.
Shades of gray redux: the Paleoindian/Early Archaic “Transition” in the Northeast
Analytical Archaeology
Regional diversity within the core technology of the Howiesons Poort techno-complex
A geometric morphometric assessment of plan shape in bone and stone Acheulean bifaces from the Middle Pleistocene site of Castel di Guido, Latium, Italy
The transition from Paleoindian to Archaic in the Middle Tennessee Valley
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2019, Journal of Archaeological ScienceCitation Excerpt :Such a reduction in size related to such practices lead some authors to propose the concept of stone tool ageing or senescence (Lycett, 2010; Shott, 2010). Different types of stone tools, including scrapers (Andrews et al., 2015; Dibble, 1984), handaxes (Archer and Braun, 2010; Iovita and McPherron, 2011; McPherron and Dibble, 1999), and projectile points (Buchanan, 2006; Buchanan and Collard, 2010b; Charlin and González-José, 2012; de Azevedo et al., 2014; Flenniken and Raymond, 1986; González-José and Charlin, 2012; Okumura and Araujo, 2014; Shott et al., 2007) can be modified through resharpening and rejuvenation practices. In the case of lithic stemmed projectile points, the blade will be the region that presents the greater potential to be modified by resharpening or rejuvenation in comparison to the stem (Fig. 3, Charlin and González-José, 2012).
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