Résumé
The origins of viticulture and the domestication of the grapevine have been, for decades, the subject of much research and works, notably on the basis of archaeobotanical remains. Size and shape differences of grape pips have been used to identify wild and domesticated grapevines. Analyses have been performed on archaeological material using several measurements: length and breadth of the pip, length of the stalk, placement of the chalaza and indices involving these measurements (e.g., Mangafa & Kotsakis 1996). First investigations suggested that the performances of traditional methods based on size parameters can vary largely when applied to modern cultivars (Bouby & Marinval 2001). Recent studies using size measurements and ratios highlighted the importance of comparing archaeological material to a representative reference collection of mordern cultivars and wild populations (Bouby et al. 2013). The shape of the grape pip offers features allowing not only the distinction between wild and domesticated grapevines, but also the identification of cultivars. This approach is based on pip outline analysis using Elliptic Fourier transform (Terral et al. 2010, Pagnoux et al. 2015). However, reproducibility and measurement errors has not been extensively tested, especially for traditional methods based on size features. Yet well founded, both traditional and geometric morphometric methods need rock-solid methodological foundations.This paper aims to propose a reproducible and reliable method that combines the best discrimination between wild and domesticated grapevine. The analyses were performed on a set of modern reference consisting of 34 cultivated varieties and 13 wild individuals. Then we benchmarked predicted identification of grape pips using various combinations of measurements, provided by the above-cited works, and using state-of-the-art statistical approaches.Finally, archaeological grape pips were compared to the set of modern reference using the same measurements. We used, as a case study, grape pips from three sites located in Northern and Southern Greece and dated from the Final Neolithic (ca. 4500-4000 BC) to the Late Bronze Age (1500-1200 BC): of Dikili Tash, Tsoungiza and P.O.T.A. Romanou.