Fishing intensification as response to Late Holocene socio-ecological instability in southeastern South America

Abstract

The emergence of plant-based economies have dominated evolutionary models of Middle and Late Holocene pre-Columbian societies. Comparatively, the use of aquatic resources and the circumstances for intensifying their exploitation, have received little attention. Here we reviewed the stable carbon and nitrogen isotope composition of 390 human individuals from Middle and Late Holocene coastal sambaquis, a long-lasting shell mound culture that flourished for nearly 7000 years along the Atlantic Forest coast of Brazil. Using a newly generated faunal isotopic baseline and Bayesian Isotope Mixing Models we quantified the relative contribution of marine resources to the diet of some of these groups. Through the analysis of more than 400 radiocarbon dates we show that fishing sustained large and resilient populations during most of the Late Holocene. A sharp decline was observed in the chronology of non-ceramic sites from ca. 2200 years ago, possibly reflecting the dissolution of several nucleated groups into smaller social units, coinciding with substantial changes in coastal environments. The adoption of ceramics from ca. 1200 years ago is marked by innovation and intensification of fishing practices, in a context of increasing social and ecological instability in the Late Holocene.

Duas décadas depois das “Novas perspectivas na reconstituição do modo de vida dos sambaquieiros: uma abordagem multidisciplinar”

“…Análises isotópicas também avançaram muito nesse período. Associadas a dados da zooarqueologia, essas pesquisas confirmaram a pesca como principal forma de aquisição de proteína animal (BASTOS et al, 2014;COLONESE et al, 2014;DIGIUSTO, 2023a;KLOKLER et al, 2018;PEZO-LANFRANCO et al, 2018a;TOSO et al, 2021). Análises de isótopos estáveis de carbono e nitrogênio, mesmo realizadas sobre colágeno 9 , atestam também uma forte contribuição das plantas à dieta total, demonstrando que estas respondiam por cerca de 10% ou mais do consumo de proteínas, além de representarem a maior parte do consumo de calorias dessas pessoas (TOSO et al, 2021).…”

“…A abordagem arqueofaunística tem reforçado a importância dos moluscos como material de construção dos montículos (e.g. KLOKLER et al, 2018), e estudos isotópicos confirmam seu papel secundário na dieta (BASTOS et al, 2014), ainda que não desprezível (TOSO et al, 2021).…”