Blank predetermination in the Iberian Acheulean. Insight from the cleaver on flake assemblage of Casal do Azemel site (Leiria, Portugal) by a Geometric Morphometric approach

Abstract

Over the last decades, the increase of data available for the study of the archaeological topic in the Iberian Peninsula during the Middle Pleistocene has favoured the understanding of the technological trends of the Iberian Acheulean assemblages. These have features of a Large Flake Acheulean (LFA), displaying, among other traits, a significant presence of cleavers on flake, a specific tool type that is of great cultural and technological value. Particularly, these artefacts are privileged to discuss the importance of blank predetermination in the Acheulean techno-complex. Following this reason, in the present work we aimed to explore this topic through the 2D Geometric Morphometric Analysis of the cleaver on flake assemblage from Casal do Azemel (Leiria, Portugal), an example of a paradigmatic Iberian Acheulean site that has one of the largest collections of this type of tools in Western Europe. The results obtained revealed that no significant morphological differences were found according to the technological solutions applied to the acquisition of the blank and its secondary transformation. Considering that in most of the cases these tools display a low degree of secondary transformation, these data suggest that underlying the production of Casal do Azemel’s cleaver on flake assemblage was not only a technological and cognitive flexibility (given its typological composition), but also a conceptual, structural, and morphological standardisation. These observations allowed us to discuss the significance of blank predetermination in the Acheulean, implying the existence of greatly structured technical and cognitive prerequisites.