A short-term, task-specific site: Epipalaeolithic settlement patterns inferred from marine shells found at Praileaitz I (Basque Country, Spain)

International audienceThe frequency of mollusks, shellfish, fish, seabirds, and marine mammal remains from archaeological sites in the Vasco-Cantabrian region of Northern Spain attests to the relatively intense exploitation of marine resources during the Upper Palaeolithic, Epipalaeolithic, and Mesolithic. These coastal resources were utilised for both technical and symbolic purposes, especially two gastropods (Littorina saxatilis/complexa/arcana and Littorina obtusata) that were almost continuously used for personal ornamentation. The shell accumulation at Praileaitz I, dated to c. 10,000 and 11,500 cal BP, provides new data concerning the interplay between Epipalaeolithic prehistoric hunter–gatherers and coastal environments. We developed a method based on identifying the accumulation's taxonomic diversity combined with a taphonomic, morphometric, and microscopic analysis of the shells in order to characterise the accumulation. The shell assemblage, composed almost exclusively of L. saxatilis/complexa/arcana and L. obtusata, provided no evidence for the shells being suspended as ornaments. Comparisons with modern and archaeological reference collections suggest the shells were collected by humans from a thanatocenosis and that the accumulation is composed only of the smallest shells with a high proportion showing breakage resulting from crab predation. Given the frequent use of these shell species as personal ornaments in the Vasco-Cantabrian region during prehistory, we propose that the accumulation represents discarded raw material considered unsuitable for the manufacture of personal ornaments. Finally, the lack of other archaeological remains of any kind leads us to conclude that the cave's brief occupation was connected to the specialised activity of bead manufacture