Une baleine grise dans le Périgord magdalénien : identification taxinomique d’une pointe de projectile en os de La Madeleine (Dordogne, France) par empreinte peptidique de masse du collagène

Abstract

The Cetacean bone artifact described in this paper is the result of excavations carried out in La Madeleine (Tursac, Dordogne) under the direction of D. Peyrony, between 1910-1913. It was discovered in the middle layer (“couche moyenne”) of the stratigraphy described by Capitan and Peyrony and subsequently attributed to the “Magdalenian V” by H. Breuil (i.e the beginning of the Upper Magdalenian). This layer corresponds to layers C25 to C20 of the stratigraphy established later by J.-M. Bouvier. Two radiocarbon dates are currently available (C21: 12750 ± 240 BP, Ly 920; and C25: 13070 ± 190 BP, Ly 921). The artifact was recently identified as Cetacean bone during an integrated study of the bones and reindeer antlers kept at the Musee National de Prehistoire (Peyrony and Bouvier collections). It is a fully worked object, elongated in shape (129 X 13.2 X 12.8 mm; 18.6 g) with straight outline and profile, a circular cross-section and parallel sides. It is interpreted as a mesio-proximal fragment of projectile point. Collagen peptide mass fingerprinting (PMF) was applied to taxonomically identify the bone artefact, as a part of the PaleoCet project. Also known as ZooMS, collagen PMF discriminates taxonomic groups based on differences in the collagen protein sequence observed through Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The bone subsamples from the exterior and interior of the artifact produced similar MALDI-TOF spectra, both of which could be confidently identified as gray whale (Eschrichtius robustus). The artifact from La Madeleine is the first evidence of the presence of this species in Atlantic waters at the end of MIS2, suggesting continuity between the Pleistocene and Holocene populations of this species. Moreover, to our knowledge, this gray whale bone artifact represents the oldest identified gray whale in an archaeological context, thus first witness of the millennia-old interactions between humans and this highly coastal whale species. The manufacturing of the La Madeleine artifact on the Basque coast, followed by its circulation through the western Pyrenees and then towards the north at the east of Landes and Gironde up to Perigord (a travel distance of roughly 350 km), might be the most plausible route taken by this artifact to reach La Madeleine.