Sambaqui of Jabuticabeira II

The Jabuticabeira II assemblage sits within the wider Sambaqui tradition of the South American Atlantic coast — communities that built conspicuous mounded deposits of shells, bone and cultural material. Radiocarbon dates from the site cluster between 742 BCE and 1 BCE, placing these burials and deposits firmly in the late Holocene coastal record.

Archaeological data indicates a long history of coastal adaptation: repeated deposition of shellfish remains, episodic construction of mound features, and the interment of individuals within mound contexts. Such monumental deposits are archaeological signatures of sustained occupation and the aggregation of food, craft refuse and ritual activity over generations. Limited evidence suggests that Sambaqui communities at Jabuticabeira II emerged from local fisher-hunter-gatherer populations that intensified marine resource use rather than large-scale population replacement.

Genetic data from 14 individuals provides a parallel line of evidence. While genetics cannot by itself assign cultural practices, concordance between material continuity and a stable maternal lineage (see Genetics) supports the interpretation of long-term regional persistence. At the same time, stratigraphic complexity and regional interactions mean that origins are best seen as a tapestry of local continuity and periodic contact rather than a single founding event.

Daily life at Jabuticabeira II would have been shaped by the sea: shellfish, fish and coastal fauna dominate the midden deposits, and archaeological traces point to intensive use of marine resources punctuated by seasonality. The shell mounds themselves are material records of food processing, discard and possibly commemorative acts — burials interleaved with midden layers imply that the dead were deposited within places of daily subsistence and memory.

Material remains recovered from Sambaqui contexts elsewhere include stone tools, marine shell ornaments and worked bone; these suggest craft specialization and networks of exchange. The scale of some mounds implies social coordination beyond the nuclear family, possibly reflecting communal feasting, ritual gatherings or territorial markers. However, preservation bias and incomplete excavation mean that many social interpretations remain tentative. Stable-isotope studies in comparable coastal sites typically reveal high marine protein intake, but direct isotopic data from every Jabuticabeira II individual is limited or absent, so dietary reconstructions should be treated cautiously.

The genetic dataset from Jabuticabeira II comprises 14 ancient individuals dated between 742 BCE and 1 BCE. Mitochondrial DNA is uniformly C1c across all 14 samples, indicating a remarkable maternal homogeneity in this cemetery sample. On the paternal side, Y-chromosome haplogroup Q is the most frequent (observed in 9 identified male individuals), a lineage commonly found among Native American populations.

These genetic signals have several possible interpretations. Uniform mtDNA C1c could reflect maternal continuity — perhaps a stable local maternal pool, founder effects within a burial community, or sampling bias linked to preservation or burial practice. The prevalence of Y-haplogroup Q aligns with broad Pan-American paternal ancestry patterns but does not, by itself, identify specific regional origins or migrations. Comparative aDNA from other Sambaqui sites and inland groups is limited; therefore, while the Jabuticabeira II genomes provide clear markers of Indigenous ancestry and local continuity, broader population dynamics (gene flow, marriage networks, mobility) remain areas for further study.

Importantly, 14 samples offer moderate statistical power: conclusions about population structure are informative but not definitive. Future sampling, combined with isotopic and archaeological context, will refine interpretations about kinship, residence patterns (e.g., matrilocality vs. patrilocality) and connections to contemporary Indigenous groups.

The material and genetic traces from Jabuticabeira II connect past coastal lifeways to the living cultural landscapes of Atlantic Brazil. Sambaqui mounds are visible markers of deep-time coastal habitation and social complexity; their genetic signatures suggest persistent ancestral lines that may link to present-day Indigenous communities, though direct lineage claims require broader, ethically guided sampling and community collaboration.

Archaeogenetic research here contributes to understanding continuity and change: it can corroborate archaeological signals of long occupation, illuminate past mobility, and inform cultural heritage management. At the same time, ethical stewardship is essential — involving descendant communities in research design, interpretation and repatriation decisions ensures that scientific narratives respect living knowledge and rights.