New data about lithic raw materials indicates hominin behavioral flexibility more than one million years ago at the Oldowan sites of Barranco León and Fuente Nueva 3 (Orce, Spain)
A new article just published in the prominent scientific journal Frontiers in Earth Science sheds light on the behavior of the oldest hominins present in Europe at the Barranco León (BL) and Fuente Nueva 3 (FN 3) sites (Orce, Andalusia) more than one million years ago.
Focusing on the two raw materials used by the Orce hominins to make their stone tools, limestone and flint, the authors combine lithic studies with a unique geo-archeological and paleoecological approach to reveal fascinating information about differential hominin activities at these and other European Oldowan sites.
The results are the fruit of years of collaborative research by the authors, led by lithic specialist and Fuente Nueva 3 excavations director Deborah Barsky (IPHES-CERCA) in the framework of the OrceProject directed by Juan Manuel Jiménez-Arenas (UGR). The Orce lithics team benefits from the expertise from the IPHES and URV: Stefania Titton (Margarita Salas Contract-URV), Amèlia Bargalló (Juan de la Cierva-Incorporation), Robert Sala Ramos (Director of the IPHES-CERCA) and recently re-incorporates experienced researchers in petrography and geology from the EPCC-CERPT (France): Sophie Grégoire and Thibaud Saos. The research also includes OrceProject site technician Alexia Serrano-Ramos and director of the Barranco León excavations Jose Antonio Solano García (UGR); as well as benefiting from collaborations with geologist Oriol Oms (UAB) and Isidro Toro-Moyano (AEMG).
After years of systematic excavations and multidisciplinary research, the BL and FN 3 sites, dated respectively to 1.4 and 1.2 Ma, have yielded abundant lithic and faunal records that offer a wealth of information about the oldest human groups to have existed outside of Africa during the late Early Pleistocene. These open-air sites were located on the shores of an ancient saline lake in a setting with abundant fresh water sources. This water and vegetation-rich environment supported a profusion of animals, including mega herbivores like elephants and hippos, as well as a range of carnivorous animals, like giant hyenas and saber-toothed tigers.
This landscape was also favorable to hominins, who evidently found the area to their liking for its abundance of readily available mineral resources with which they made their tools. The hominins gathered and used local limestone and flint, preferring the latter mainly (but not exclusively) for heavy-duty percussive tasks, and the former to knap small-sized flakes that were apparently used for cutting meat and viscera from animal carcasses.
Results from this study stress that, even though these two sites are situated very close to one another, their geological and chrono-climatic situations differed in ways that subtly - but significantly – affected how hominins took advantage of the lithic resources obtainable from their milieu. Combining data from the lithic assemblages with geological surveys and petrographic analyses, the authors reveal remarkable techno-economic features that allow to more accurately profile each site’s unique context in accordance to the kinds of activities hominins were carrying out.
At BL, limestone cobbles of various shapes sizes and detrital flint nodules were obtained directly from within a unique high-energy depositional context and exploited in situ. Meanwhile at FN 3, silicified limestone blocks were exploited, complimented by some cobbles originating from a yet to be identified source, while relatively good quality flint was brought to the site from nearby secondary sources and sometimes re-knapped in situ to produce the desired small flakes.
The team’s extensive surveys have allowed to geo-localize numerous flint outcrops in the Orce environs and to catalogue lithic formal variability in the zone. In addition, samples were collected from each outcrop to create a referential that will be made available at the Centro de Interpretación Primeros Pobladores de Europa ‘Josep Gibert’ in Orce and constitutes an important addition to future research on the lithic assemblages.
Petrographic analyses buttressing this study include microfaciological characterization of the flint in the archeological and environmental samples to identify potential sources in relation to the local lithological cartography and propose a minimum and maximum supply distance for each type. Geochemical characterization of the flints, as well as surface analyses using the EDX microprobe coupled with SEM observations to distinguish the limestone and flint from both assemblages, allows to associate each type with one or more outcrop points all situated within a radius of ten kilometers from the deposits. Additional macroscopic observations were useful to facilitate the search for refitting lithics sets and evaluate possible hominin selective processes.
Data from archeometry and typo-technological analyses provides coherent reconstructions of the operational schemes used during the knapping and (occasionally) shaping processes, defining specific chains of action applied to each raw material and highlighting differential behavioral patterns between the sites. Size-range variance and differential tool category frequencies are explained in terms of site-specific techno-economic factors, as well as intra-site geo-depositional specificities.
While both assemblages fit within an Oldowan-type profile, dominated by non-standardized tools and simple but systematic knapping strategies, this study shows that the hominins were capable of adapting their technologies to the morphology and mechanical properties of the available raw materials, selecting them in relation to their adequacy to perform a range of tasks.
The behavioral patterns identified from this holistic study at BL and FN 3 are compared and contrasted with other well-documented European Oldowan sites (1.6 to 0.78 Ma), helping to refine our knowledge about the hominins responsible for these accumulations. This research pinpoints a number of variables conditioning the kinds of data available to archeologists from these contexts, such as: site formation processes, lithological context, preservation conditions, taphonomy, site type and extension and hominin activities.
While complications exist in the interpretation of such ancient human contexts, this research reveals the significant role played by studying raw materials to determine hominin behavioral patterning. The specific types, qualities and even shapes and sizes of the rocks available in each context played a key role in dictating the types and morphology of the tools that were made, while cultural and cognitive stages of the hominins determined the range of formal possibilities of anthropic intervention on stone.
Like in Africa, European Oldowan hominins settled in water-rich environments that assured their sustenance and guaranteed access to plant, meant and mineral resources. Results from the lithic studies of BL and FN 3 supports recently published paleoecological data suggesting adaptive flexibility of the Orce hominins that maintained their populations in the same area even in the face of climatic change.
European Oldowan toolkits are characterized by small flakes and cores, while their ubiquitous percussive tools indicate a considerably wide range of actions signaling behavioral variability in spite of cultural uniformity. They used hard hammer direct percussion and bipolar-on-anvil stone reduction strategies dominated by unifacial and orthogonal strategies and occasionally created multipolar and centripetal core forms. The hominins thus chose from this fixed range of knapping techniques, adjusting their strategies in accordance to the quality, sizes and shapes of the rocks available to them in each territorial context.
This new study shows how raw material variability played a role in shaping hominin behaviors, providing a means to gain new interpretations and revealing multiple facets of the European Oldowan, confirming once again the foundational role played by the Orce sites in building our understanding of ancient human lifeways.
Barsky D, Titton S, Sala-Ramos R, Bargalló A, Grégoire S, Saos T, Serrano-Ramos A, Oms O, Solano García J-A, Toro-Moyano I and Jiménez-Arenas JM (2022) The Significance of Subtlety: Contrasting Lithic Raw Materials Procurement and Use Patterns at the Oldowan Sites of Barranco León and Fuente Nueva 3 (Orce, Andalusia, Spain). Front. Earth Sci. 10:893776. doi: 10.3389/feart.2022.893776