Reinvestigation of Buca della Iena and Grotta del Capriolo shed light onto late Neanderthals in northwestern Tuscany (Italy)

Buca della Iena and Grotta del Capriolo are two small karst caves in northwestern Tuscany (Italy). At both sites, the deposits were completely excavated between 1966 and 1972 and revealed Mousterian lithic assemblages associated with Pleistocene fauna (Pitti and Tozzi, 1971). The archaeological sequence at Buca della Iena rests upon a flowstone dividing spit 14 from spit 15. No artefact was reported from underneath the flowstone and spit 15 is considered a carnivore den. The flowstone’s TH230/U238 date from 1968 is <41 ka and <51 ka, therefore aligning with those obtained from a flowstone in the neighbouring Grotta all’Onda site (39.3 ± 3.2 ka - Fornaca-Rinaldi and Radmilli, 1968). This suggests the presence of Neanderthals in northern Tuscany at the very end of their history (41.1–39.3 ka cal - Higham et al., 2014). Unfortunately, the flowstones were destroyed, with no samples preserved, and subsequent investigations at Grotta all’Onda failed to replicate the original date (Berton et al., 2003). Consequently, together with a stratigraphical and artefact reassessment, a decision was made to conduct new radiocarbon dating on bones from Buca della Iena and Grotta del Capriolo. Bone samples, selected to represent the entirety of the archaeological sequence, underwent scrutiny for nitrogen content. Ten samples were processed for AMS radiocarbon dating: five Buca della Iena samples treated with ultrafiltration pretreatment, one Buca della Iena sample and four Grotta del Capriolo samples treated without ultrafiltration due to lower collagen yields. The resulting dates indicate that the associated lithic assemblages can be confidently attributed to the mid-MIS 3 period (54 – 40 ka cal BP at Grotta del Capriolo, 50 – 40 ka cal BP at Buca della Iena). These new results provide a reliable chronology for the late Mousterian sites in northwestern Tuscany and stimulate hypotheses concerning the fate of Neanderthal groups living along the western coast of the Italian peninsula.