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.

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.