Jabuticabeira II — Sambaqui, 1300 BP

The Sambaqui phenomenon — vast shell mounds and concentrated coastal deposits — is one of South America's most striking Holocene landscapes. Jabuticabeira II sits on the southern Brazilian shore and represents a moment within this long coastal sequence. Archaeological data indicates sustained shellfish harvesting, episodic mound construction, and use of these deposits as living, ceremonial, and burial spaces.

The specimen dated here to between 553 and 646 CE falls well within the late prehistoric sequence of sambaqui builders. Limited evidence suggests the social and economic systems that created the mounds had deep roots: shell-mound formation and coastal specialization began centuries to millennia earlier in different parts of the Brazilian coast.

Material culture from Jabuticabeira II—shell, fish bone, occasional worked stone and bone—reflects intensive marine resource use combined with localized trade or exchange. These mounds were not simply refuse piles but cumulative records of habitation and memory, rising as silent monuments along lagoons and beaches. Archaeological interpretation emphasizes continuity and regional variability: the people who shaped these landscapes were expert coastal foragers whose practices changed through time in response to environment and social choices.

The genetic finding from this context is a single mitochondrial genome assigned to haplogroup B2. B2 is one of the founding maternal lineages widespread among Indigenous peoples across the Americas and is commonly observed in both ancient and modern Native American populations. This maternal signal aligns with expectations for long-standing Indigenous ancestry on the Brazilian coast.

However, it is essential to emphasize the preliminary nature of conclusions: this dataset is one individual (sample count = 1). With such limited sampling, population-level inferences — about continuity, migration, or demographic change — remain tentative. The absence of reported Y‑DNA prevents any assessment of paternal lineages at Jabuticabeira II.

Archaeogenetics complements archaeology here by anchoring one human life within broader continental maternal lineages. Future work with more radiocarbon-dated individuals, genome-wide data, and comparative sampling across sambaqui sites could resolve questions of regional continuity, kinship within mounds, and links between coastal and inland groups. For now, the mtDNA B2 result is a clear but solitary thread tying this sambaqui inhabitant to pan-American maternal ancestry.