The Application of Elliptic Fourier Analysis in Understanding Biface Shape and Symmetry Through the British Acheulean

Acheulean biface shape and symmetry have fuelled many discussions on past hominin behaviour in regards to the ‘meaning’ of biface technology. However, few studies have attempted to quantify and investigate their diachronic relationship using a substantial dataset of Acheulean bifaces. Using the British archaeological record as a case study, we first perform elliptic Fourier analysis on biface outlines to quantify and better understand the relationship between biface shape and individual interglacial periods. Using the extracted Fourier coefficients, we then detail the nature of symmetry throughout this period, before investigating both shape and symmetry in parallel. The importance of size (through biface length) as a factor in biface shape and symmetry is also considered. Results highlight high levels of symmetry from Marine Isotope Stage (MIS) 13, followed by increasing asymmetry through the British Acheulean. Other observations include a general shift to ‘pointed’ forms during MIS 9 and 7 and the importance of size in high biface symmetry levels. This article concludes by discussing the potential importance of secondary deposition and palimpsest sites in skewering the observed relationships throughout the Palaeolithic.