No abstract

A reference inventory of prehistoric marine mollusks from the Rio das Ostras region was created based on an excavation carried out at the Sambaqui da Tarioba shellmound. Patterns of richness and biogeography were studied, and the representativeness of bivalve and gastropod diversities found at this archaeological site were inferred. A total of 47 taxa belonging to 28 families, most of which from unconsolidated substrates, was identified. The shellmound species composition does not differ from the present-day composition. All recorded species are characteristic of a wide transition zone between the south of the states of Espírito Santo (21°S) and Rio Grande do Sul (32°S). Thus, the data show little evidence of evolution in the composition, richness,and biodiversity distribution patterns of mollusks in the Rio das Ostras region. Likewise, a reconstitution of the paleoenvironment from the functional characteristics of the shellmound species indicates that the locality's geomorphology and climate remained largely unchanged in the last 4,000 years BP

Since the beginning of the Holocene, hunter-gatherers have occupied the central-south Brazilian coast, as it was a very productive estuarine environment. Living as fishers and mollusk gatherers, they built prehistoric shellmounds, known as sambaqui, up to 30 m high, which can still be found today from the Espírito Santo (21°S) to Rio Grande do Sul (32°S) states, constituting an important testimony of paleodiversity and Brazilian prehistory. The chronology of the Sambaqui da Tarioba, situated in Rio das Ostras, Rio de Janeiro, is discussed herein. Selected well-preserved shells of Iphigenia brasiliana and charcoal from fireplaces in sequential layers were used for radiocarbon dating analysis. Based on a statistical model developed using OxCal software, the results indicate that the settlement occupation begun most probably around 3800 cal BP and lasted for up to 5 centuries.

Since the beginning of the Holocene, hunter-gatherers have occupied the central-south Brazilian coast, as it was a very productive estuarine environment. Living as fishers and mollusk gatherers, they built prehistoric shellmounds, known as sambaqui, up to 30 m high, which can still be found today from the Espírito Santo (21°S) to Rio Grande do Sul (32°S) states, constituting an important testimony of paleodiversity and Brazilian prehistory. The chronology of the Sambaqui da Tarioba, situated in Rio das Ostras, Rio de Janeiro, is discussed herein. Selected well-preserved shells of Iphigenia brasiliana and charcoal from fireplaces in sequential layers were used for radiocarbon dating analysis. Based on a statistical model developed using OxCal software, the results indicate that the settlement occupation begun most probably around 3800 cal BP and lasted for up to 5 centuries.