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The land snails from the Final Palaeolilhic and Early Neolithic archaeological layers ofthe cave Arma dello Stefanin in the Pennavaira Valley(Aquila d’Arroscia,Imperia,Northern Italy).Two limits affect the results of the palaeoecological studies of the land snails from the archaeologicallayers of the Arma dello Stefanin.First the abundance of big sized Molluscs,usually of less ecologicalinterest,bad indicators for environmental changes.Second the dominance throughout the whole stratigra-phy of two common elements,Helicigona cingulata,with a rupestral behaviour,and Discus rotundatuswhich inhabits sheltered and damp places.The absence of small species,good environmental indicators,and the continuous high percentage of the above mentioned species,give insufficient evidence of theslow and narrow changes inside the malacological structure.In the case of the Arma dello Stefanin,a palaeoecological profile based on the land snails should be impossible without the help of the anthraco-logical analyses.According to both these elements,six climatic periods have been recognised,since thefinal glacial cold oscillation of the Dryas Ⅱ,dated to 10750±300 bc(HAR-6915),to the Middle AtlanticImpressed Ware Culture dated to 4660±60 bc(Bin-3276).
The land snails from the Final Palaeolilhic and Early Neolithic archaeological layers of the cave Arma dello Stefanin in the Pennavaira Valley (Aquila d’Arroscia, Imperia, Northern Italy). Two limits affect the results of the paeoeoecological studies of the land snails from the archaeologicallayers of the Arma dello Stefanin. First the abundance of big sized Molluscs, usually of less ecologicalinterest, bad indicators for environmental changes. Secondary the dominance throughout the whole stratigra-phy of two common elements, Helicigona cingulata, with a rupestral behavior, and Discus rotundatus inhabits sheltered and damp places. the absence of small species, good environmental indicators, and the continuous high percentage of the above mentioned species, give insufficient evidence of the slumps and narrow changes inside the malacological structure. the case of the Arma dello Stefanin, a palaeoecological profile based on the land snails should be impossible without the help of the anthraco-logical a nalyses. Both claims to both these elements, six climatic periods have been recognized, since the final glacial cold oscillation of the Dryas II, dated to 10750 ± 300 bc (HAR-6915), to the Middle Atlantic Ware Ware Culture dated to 4660 ± 60 bc ( Bin-3276).