High handaxe symmetry at the beginning of the European Acheulian: The data from la Noira (France) in context

Abstract

In the last few decades, new discoveries have pushed the beginning of the biface-rich European Acheulian from 500 thousand years (ka) ago back to at least 700 ka, and possibly to 1 million years (Ma) ago. It remains, however, unclear to date if handaxes arrived in Europe as a fully developed technology or if they evolved locally from core-and-flake industries. This issue is also linked with another long-standing debate on the existence and behavioral, cognitive, and social meaning of a possibly chronological trend for increased handaxe symmetry throughout the Lower Paleolithic. The newly discovered sites can provide a link between the much older Acheulian in Africa and the Levant and the well-known assemblages from the later European Acheulian, enabling a rigorous testing of these hypotheses using modern morphometric methods. Here we use the Continuous Symmetry Measure (CSM) method to quantify handaxe symmetry at la Noira, a newly excavated site in central France, which features two archaeological levels, respectively ca. 700 ka and 500 ka old. In order to provide a context for the new data, we use a large aggregate from the well-known 500 ka old site of Boxgrove, England. We show that handaxes from the oldest layer at la Noira, although on average less symmetric than both those from the younger layers at the same site and than those from Boxgrove, are nevertheless much more symmetric than other early Acheulian specimens evaluated using the CSM method. We also correlate trends in symmetry to degree of reduction, demonstrating that raw material availability and discard patterns may affect observed symmetry values. We conclude that it is likely that, by the time the Acheulian arrived in Europe, its makers were, from a cognitive and motor-control point of view, already capable of producing the symmetric variant of this technology.

Were Acheulean Bifaces Deliberately Made Symmetrical? Archaeological and Experimental Evidence

“…Quantitative studies have found that, while there are several factors that can affect biface morphology, there are discernible improvements in symmetry over the course of the Acheulean in East Africa (Schick & Toth 2017;Shipton 2018), the Levant (Grosman et al 2011a;Saragusti et al 1998), northwestern Europe (Iovita et al 2017) and India (Shipton 2016).…”

From side to side: Symmetry in handaxes in the British Lower and Middle Palaeolithic

“…However, Iovita and colleagues (Iovita et al, 2017) have recently argued that symmetry is anything but passive, rather it is a deliberately imposed feature on handaxes from Brinay la Noire on the Cher river, in the middle reaches of the Loire basin. Those from the lower level, stratum B, are c. 700 kya and represent the earliest securely contextualised and dated Acheulean handaxes yet found in western Europe.…”

“…In which case symmetry may reflect the bauplan of earlier hominin migrants (Bridgland and White, 2015). One new and important factor is raised by Iovita et al (2017). Where and when in its life cycle, and at what kind of site a handaxe is discarded or lost influences the modern interpreter's view of symmetry, because it may vary with different locations in the landscape.…”

Manual restrictions on Palaeolithic technological behaviours

“…The latter strategy also employed specialist grinding stones during the preparation of flake platforms. The terms EAH and LAH used here refer to general increases in flaking extent, shaping, volume control, symmetry, the use of intentional ‘thinning’ flakes, soft-hammer percussion and prepared flake platforms in later Acheulean handaxes ( Saragusti et al, 1998 ; Schick & Clark, 2003 ; Grosman, Goldsmith & Smilansky, 2011 ; Diez-Martín et al, 2014 ; Stout et al, 2014 ; Gallotti & Mussi, 2017 ; Iovita et al, 2017 ; Shimelmitz et al, 2017 ). While these differences are often clearest when tools produced >1 Mya are compared to those produced after ∼0.5 Mya, we do not mean to imply uniform linear progression of forms across regional records ( Vaughan, 2001 ; Gowlett, 2013 ; Moncel et al, 2015 ; McNabb & Cole, 2015 ).…”

“…Bifaces go on to typify the next >1 million years of the archaeological record across the Old World ( Lycett & Gowlett, 2008 ; Gowlett, 2015 ; Moncel et al, 2015 ) until the onset of Middle Palaeolithic technologies ∼300 Kya ( Moncel et al, 2011 ; Tryon & Faith, 2013 ; Adler et al, 2014 ). The nature and extent of any chronological changes to stone technology during the Acheulean are debated (e.g., Vaughan, 2001 ; Chauhan, 2009 ; Gowlett, 2011 ; McNabb & Cole, 2015 ; Moncel et al, 2015 ; Gallotti, 2016 ), however, there are indications that later Acheulean bifacial tools (handaxes in particular) were at times produced using soft-hammer percussion, became thinner relative to their width (more ‘refined’), displayed greater evidence of intentional thinning, volume control (mass distribution), investment (e.g., time, skill), shaping and symmetry ( Gowlett, 1986 ; Saragusti et al, 1998 ; Schick & Clark, 2003 ; Grosman, Goldsmith & Smilansky, 2011 ; Beyene et al, 2012 ; García-Medrano et al, 2014 ; Li et al, 2018 ; Moncel et al, 2016 ; Gallotti & Mussi, 2017 ; Iovita et al, 2017 ; Shimelmitz et al, 2017 ), and at times displayed evidence of platform preparation prior to a flake’s removal ( Stout et al, 2014 ). Together, these technologies describe ∼3 million years of stone tool production and use during the Lower Palaeolithic.…”