The pattern of emergence of a Middle Stone Age tradition at Gademotta and Kulkuletti (Ethiopia) through convergent tool and point technologies

Longstanding behavioural stability in West Africa extends to the Middle Pleistocene at Bargny, coastal Senegal

Middle Stone Age (MSA) technologies first appear in the archaeological records of northern, eastern and southern Africa during the Middle Pleistocene epoch. The absence of MSA sites from West Africa limits evaluation of shared behaviours across the continent during the late Middle Pleistocene and the diversity of subsequent regionalized trajectories. Here we present evidence for the late Middle Pleistocene MSA occupation of the West African littoral at Bargny, Senegal, dating to 150 thousand years ago. Palaeoecological evidence suggests that Bargny was a hydrological refugium during the MSA occupation, supporting estuarine conditions during Middle Pleistocene arid phases. The stone tool technology at Bargny presents characteristics widely shared across Africa in the late Middle Pleistocene but which remain uniquely stable in West Africa to the onset of the Holocene. We explore how the persistent habitability of West African environments, including mangroves, contributes to distinctly West African trajectories of behavioural stability.

The revolution that still isn't: The origins of behavioral complexity in Homo sapiens

The behavioral origins of Homo sapiens can be traced back to the first material culture produced by our species in Africa, the Middle Stone Age (MSA). Beyond this broad consensus, the origins, patterns, and causes of behavioral complexity in modern humans remain debated. Here, we consider whether recent findings continue to support popular scenarios of: (1) a modern human 'package,' (2) a gradual and 'pan-African' emergence of behavioral complexity, and (3) a direct connection to changes in the human brain. Our geographically structured review shows that decades of scientific research have continuously failed to find a discrete threshold for a complete 'modernity package' and that the concept is theoretically obsolete. Instead of a continent-wide, gradual accumulation of complex material culture, the record exhibits a predominantly asynchronous presence and duration of many innovations across different regions of Africa. The emerging pattern of behavioral complexity from the MSA conforms to an intricate mosaic characterized by spatially discrete, temporally variable, and historically contingent trajectories. This archaeological record bears no direct relation to a simplistic shift in the human brain but rather reflects similar cognitive capacities that are variably manifested. The interaction of multiple causal factors constitutes the most parsimonious explanation driving the variable expression of complex behaviors, with demographic processes such as population structure, size, and connectivity playing a key role. While much emphasis has been given to innovation and variability in the MSA record, long periods of stasis and a lack of cumulative developments argue further against a strictly gradualistic nature in the record. Instead, we are confronted with humanity's deep, variegated roots in Africa, and a dynamic metapopulation that took many millennia to reach the critical mass capable of producing the ratchet effect commonly used to define contemporary human culture. Finally, we note a weakening link between 'modern' human biology and behavior from around 300 ka ago.

Why did hunting weapon design change at Abri Pataud? Lithic use-wear data on armature use and hafting around 24,000-22,000 BP

Projectile technology is commonly viewed as a significant contributor to past human subsistence and, consequently, to our evolution. Due to the allegedly central role of projectile weapons in the food-getting strategies of Upper Palaeolithic people, typo-technological changes in the European lithic record have often been linked to supposed developments in hunting weaponry. Yet, relatively little reliable functional data is currently available that would aid the detailed reconstruction of past weapon designs. In this paper, we take a use-wear approach to the backed tool assemblages from the Recent and Final Gravettian layers (Levels 3 and 2) of Abri Pataud (Dordogne, France). Our use of strict projectile identification criteria relying on combinations of low and high magnification features and our critical view of the overlap between production and use-related fractures permitted us to confidently identify a large number of used armatures in both collections. By isolating lithic projectiles with the strongest evidence of impact and by recording wear attributes on them in detail, we could establish that the hunting equipment used during the Level 3 occupations involved both lithic weapon tips and composite points armed with lithic inserts. By contrast, the Level 2 assemblage reflects a heavy reliance on composite points in hunting reindeer and other game. Instead of an entirely new weapon design, the Level 2 collection therefore marks a shift in weapon preferences. Using recent faunal data, we discuss the significance of the observed diachronic change from the point of view of prey choice, seasonality, and social organisation of hunting activities. Our analysis shows that to understand their behavioural significance, typo-technological changes in the lithic record must be viewed in the light of functional data and detailed contextual information.

Reappraisal of the chronology of Orgnac 3 Lower-to Lower to Middle Paleolithic site (Ardèche, France), a regional key sequence for the Middle Pleistocene of southern France

Previous studies have suggested that the Lower-to-Middle Paleolithic transition was associated with the earliest Neanderthals, but recent research has established that the oldest Neanderthal fossils and the first signs of their technologies and behavior appear from MIS 11 or possibly earlier. To understand these changes, re-evaluation of the evidence is necessary to determine if this transition corresponds to a progressive evolution rather than abrupt change. Orgnac 3 is a key and appropriate site to study this research context. Located in southern France, it yields a long stratigraphic sequence testifying the evolution of technical and subsistence behaviors of pre-Neanderthal human groups during a Middle Pleistocene interglacial-glacial cycle. In this article, a new chronological framework is provided for the sequence based on results of dating methods applied to various types of geological materials. Speleothems and volcanic minerals, dated in previous studies by U-series and ⁴⁰Ar/³⁹Ar, respectively, show periods of calcitic crystallization and regional volcanic activity. Other materials, such as heated flints and herbivore teeth, are directly related to evidence of anthropogenic activities and are analyzed in the present work by trapped-charge dating methods such as thermoluminescence and electron spin resonance combined with uranium series (ESR/U-series). The new thermoluminescence and ESR/U-series dates confirm the attribution of the Orgnac 3 stratigraphic sequence to the MIS 10-MIS 8 period and are discussed in relation to paleoenvironmental data derived from bioarchaeological studies. The paleoanthropological levels, including the emergence of Levallois technology, are dated to ca. 275 ka (early MIS 8) and appear coeval to a wet and temperate period recorded locally, the Amargiers interstadial, defined in the regional palynological records. The implications of this reassessed chronology for the archaeological assemblages are discussed in the wider context of behavioral innovations from MIS 11 onward and their establishment in subsequent periods.

Early human impacts and ecosystem reorganization in southern-central Africa

Modern Homo sapiens engage in substantial ecosystem modification, but it is difficult to detect the origins or early consequences of these behaviors. Archaeological, geochronological, geomorphological, and paleoenvironmental data from northern Malawi document a changing relationship between forager presence, ecosystem organization, and alluvial fan formation in the Late Pleistocene. Dense concentrations of Middle Stone Age artifacts and alluvial fan systems formed after ca. 92 thousand years ago, within a paleoecological context with no analog in the preceding half-million-year record. Archaeological data and principal coordinates analysis indicate that early anthropogenic fire relaxed seasonal constraints on ignitions, influencing vegetation composition and erosion. This operated in tandem with climate-driven changes in precipitation to culminate in an ecological transition to an early, pre-agricultural anthropogenic landscape.

The emergence of the Levallois technology in the Levant: A view from the Early Middle Paleolithic site of Misliya Cave, Israel

The Early Middle Paleolithic (EMP) lithic assemblage of Misliya Cave, dated to 240-150 ka, is associated with one of the earliest occurrences of Homo sapiens outside Africa. Our research provides a detailed technological study of the lithic assemblage of stratigraphic unit 5-6c of the site, using the chaîne opératoire approach, to characterize the technological behavior of the early H. sapiens. Our results indicate that both Levallois and laminar volumetric concepts were used. The Levallois reduction strategy involved preparing subtriangular cores with steep distal edges that allowed producing a series of triangular/subtriangular Levallois blanks using a unidirectional convergent method. Laminar débitage constitutes a semirotating/rotating method. The results of our study and comparisons with other Levantine sites indicate that the EMP represents a distinct entity within the Levantine Middle Pleistocene record that can be distinguished by the earliest occurrence of a full-fledged Levallois technology in the region, laminar technology, and a distinct tool kit dominated by elongated retouched points. The level of core management involved in producing convergent Levallois products and in preparing laminar cores points to a major conceptual change from the preceding Acheulian and Acheulo-Yabrudian. This suggests a break in knapping strategies between the Lower and the Middle Paleolithic. The finding of a H. sapiens maxilla at Misliya Cave in association with the EMP industry supports the hypothesis that the introduction of the Levallois technology in the Near East was associated with an early dispersal of H. sapiens from Africa. A comparison between the Levantine EMP and other regional records indicates that different Levallois methods were routinely used by hominins from the beginning of the Middle Paleolithic and the Middle Stone Age.

Trajectories of cultural innovation from the Middle to Later Stone Age in Eastern Africa: Personal ornaments, bone artifacts, and ocher from Panga ya Saidi, Kenya

African Middle Stone Age (MSA) populations used pigments, manufactured and wore personal ornaments, made abstract engravings, and produced fully shaped bone tools. However, ongoing research across Africa reveals variability in the emergence of cultural innovations in the MSA and their subsequent development through the Later Stone Age (LSA). When present, it appears that cultural innovations manifest regional variability, suggestive of distinct cultural traditions. In eastern Africa, several Late Pleistocene sites have produced evidence for novel activities, but the chronologies of key behavioral innovations remain unclear. The 3 m deep, well-dated, Panga ya Saidi sequence in eastern Kenya, encompassing 19 layers covering a time span of 78 kyr beginning in late Marine Isotope Stage 5, is the only known African site recording the interplay between cultural and ecological diversity in a coastal forested environment. Excavations have yielded worked and incised bones, ostrich eggshell beads (OES), beads made from seashells, worked and engraved ocher pieces, fragments of coral, and a belemnite fossil. Here, we provide, for the first time, a detailed analysis of this material. This includes a taphonomic, archeozoological, technological, and functional study of bone artifacts; a technological and morphometric analysis of personal ornaments; and a technological and geochemical analysis of ocher pieces. The interpretation of the results stemming from the analysis of OES beads is guided by an ethnoarcheological perspective and field observations. We demonstrate that key cultural innovations on the eastern African coast are evident by 67 ka and exhibit remarkable diversity through the LSA and Iron Age. We suggest the cultural trajectories evident at Panga ya Saidi were shaped by both regional traditions and cultural/demic diffusion.

Early Levallois core technology between Marine Isotope Stage 12 and 9 in Western Europe

Early Levallois core technology is usually dated in Europe to the end of Marine Isotope Stage (MIS) 9 and particularly from the beginning of MIS 8 to MIS 6. This technology is considered as one of the markers of the transition from lower to Middle Paleolithic or from Mode 2 to Mode 3. Recent discoveries show that some lithic innovations actually appeared earlier in western Europe, from MIS 12 to MIS 9, contemporaneous with changes in subsistence strategies and the first appearance of early Neanderthal anatomical features. Among these discoveries, there is the iconic Levallois core technology. A selection of well-dated assemblages in the United Kingdom, France, and Italy dated from MIS 12 to 9, which include both cores and flakes with Levallois features, has been described and compared with the aim of characterizing this technology. The conclusion supports the interpretation that several technical features may be attributed to a Levallois technology similar to those observed in younger Middle Paleolithic sites, distinct from the main associated core technologies in each level. Some features in the sample of sites suggest a gradual transformation of existing core technologies. The small evidence of Levallois could indicate occasional local innovations from different technological backgrounds and would explain the diversity of Levallois methods that is observed from MIS 12. The technological roots of Levallois technology in the Middle Pleistocene would suggest a multiregional origin and diffusion in Europe and early evidence of regionalization of local traditions through Europe from MIS 12 to 9. The relationships of Levallois technology with new needs and behaviors are discussed, such as flake preference, functional reasons related to hunting and hafting, an increase in the use of mental templates in European populations, and changes in the structure of hominin groups adapting to climatic and environmental changes.

One size does not fit all: Group size and the late middle Pleistocene prehistoric archive

The role of demography is often suggested to be a key factor in both biological and cultural evolution. Recent research has shown that the linkage between population size and cultural evolution is not straightforward and emerges from the interplay of many demographic, economic, social and ecological variables. Formal modelling has yielded interesting insights into the complex relationship between population structure, intergroup connectedness, and magnitude and extent of population extinctions. Such studies have highlighted the importance of effective (as opposed to census) population size in transmission processes. At the same time, it remained unclear how such insights can be applied to material culture phenomena in the prehistoric record, especially for deeper prehistory. In this paper we approach the issue of population sizes during the time of the Lower to Middle Paleolithic transition through the proxy of regional trajectories of lithic technological change, identified in the archaeological records from Africa, the Levant, Southwestern and Northwestern Europe. Our discussion of the results takes into consideration the constraints inherent to the archaeological record of deep time - e.g., preservation bias, time-averaging and the incomplete nature of the archaeological record - and of extrapolation from discrete archaeological case studies to an evolutionary time scale. We suggest that technological trajectories of change over this transitional period reflect the robustness of transmission networks. Our results show differences in the pattern and rate of cultural transmission in these regions, from which we infer that information networks, and their underlying effective population sizes, also differed.

A reply to Douze and Delagnes's 'The pattern of emergence of a Middle Stone Age tradition at Gademotta and Kulkuletti (Ethiopia) through convergent tool and point technologies' [J. Hum. Evol. 91 (2016) 93-121]

Douze and Delagnes (2016) revisit Middle Stone Age (MSA) lithic assemblages from the Gademotta Formation (Fm.), Ethiopia. Their analysis of selected assemblages from three of the 1972 excavations expands the original typo-technological interpretations by Wendorf and Schild (1974). We particularly welcome their evaluation of our recent inferences about the function of pointed artifacts and technological patterns in the Gademotta Fm. (Sahle et al., 2013, 2014). However, we find several arguments and conclusions in Douze and Delagnes (2016) to be rather unconvincing and irreconcilable with results from analyses of whole assemblages (Wendorf and Schild, 1974; Sahle et al., 2013, 2014). Specifically, their summary attribution of all early MSA burin-like fractures on the distal tips of pointed artifacts to intentional resharpening blows, and their use of this pattern as a technological "chrono-marker" unique to the region are untenable. Here, we highlight these issues in the hopes of a clearer understanding of the evident technological patterns in the Gademotta Fm.