MOLLUSC SHELL SIZES IN ARCHAEOLOGICAL CONTEXTS IN NORTHERN SPAIN (13 200 TO 2600 CAL BC): NEW DATA FROM LA GARMA A AND LOS GITANOS (CANTABRIA)

Shellfish metrical data are a source of information about the exploitation of marine resources in the past. In this study, we propose a methodological approach based on the size structures of different rocky intertidal gastropod species. Three limpet species (Patella vulgata, Patella intermedia and Patella ulyssiponensis) and the toothed topshell Osilinus lineatus are studied from two sites in Cantabrian Spain: La Garma A and Los Gitanos caves over a period of 10 000 years, covering the Pleistocene-Holocene transition. Data are also supplied about a further sea snail species, the periwinkle Littorina littorea (Upper Magdalenian). A reduction in size can be seen, between the upper Magdalenian and the late Neolithic, in the case of the first four species. The explanation for this decline is probably related to the climate change that occurred in the transition between the Late Pleistocene and the Holocene, but it is possible that human impact might also have influenced shell sizes in the Mesolithic and Neolithic.