Michel Fontugne

New Data on a Pleistocene Archaeological Sequence in South America: Toca do Sítio do Meio, Piauí, Brazil

Sítio do Meio, discovered in the 1990s, showed a sedimentary sequence clearly composed of two sets of deposits separated by a zone of large rockfall from the massive collapse of the shelters overhang. The bottom set, slightly more than 60 cm thick, was trapped between the bedrock (upon which it rested) and the lower part of the roof fall (reaching more than 1 m in the excavation area), and yielded some charcoal without other archaeological material. New excavations, however, have revealed the presence of artifacts, additional charcoal, and an alignment of sandstone blocks providing clear boundaries for the artifact concentration. The typological and technological composition of the artifacts is classic, with tools made by shaping high-quality quartz pebbles and tools made on shaping chips or on chips obtained by bipolar percussion of quartz blocks. Quartzite was also used, but only in the manufacture of larger tools, of certain types. The toolkit is made of several convergent pieces, denticulates, rostres, scrapers, and end scrapers. Radiocarbon dating results indicate a Pleistocene age, corresponding to the end of the mid-Upper Pleistocene (MIS3). These dates confirm that Sítio do Meio is the seventh Pleistocene stratigraphic sequence known from a 20-km-radius zone, coming from different sedimentary horizons, testifying to a human presence that extends from MIS3 until the middle Holocene, in this region of Piauí. Particularly, we observed that this occupation still has periodic gaps, with phases of occupation occurring in either short or long periods. With the new data, we are able to consider the cultural specificities of each set in the context of climate data to better understand the diversity of occupation within a single territory, for example behavioral variation in the management of space, adaptive responses to environmental pressures, or potentially both at the same time.