Jabuticabeira II Sambaqui: Coastal Ancestors

Along the rocky southern shores of what is today Santa Catarina state, the shellmound—sambaqui—at Jabuticabeira II preserves the layered traces of generations who lived from roughly 742 BCE to the turn of the Common Era. Archaeological data indicates successive midden-building episodes: accumulated shell, bone, pottery, and hearths that form a visible palimpsest of coastal occupation. These mounds are not simply refuse heaps but cultural landscapes: elevated living platforms, ritual loci, and cemeteries. The material assemblage—fish and shellfish remains, stone tools, and decorated ceramics—points to a lifeway intensely adapted to the marine littoral.

Regional comparisons tie Jabuticabeira II to the broader Sambaqui tradition that arose centuries earlier along Brazil’s Atlantic coast. Limited evidence suggests mobility and exchange along the shoreline, with stylistic links in pottery and shared midden construction techniques. While the archaeological sequence provides rich ecological and cultural context, it is inherently local: Jabuticabeira II offers a window into one community within a mosaic of coastal groups, and careful stratigraphic and radiocarbon work anchors this site within the 742–1 BCE interval without implying uniform behavior across all sambaquis.

Ancient-DNA analysis from 14 individuals recovered at Jabuticabeira II provides a rare genetic portrait directly tied to a sambaqui context. Mitochondrial genomes are uniform: all 14 samples carry mtDNA haplogroup C1c, one of the founding maternal lineages recognized across the Americas. This ubiquity suggests strong matrilineal continuity within the sampled burial population, consistent with local kinship or endogamous practices, though preservation and sampling choices can bias results.

On the paternal side, Y-chromosome data show haplogroup Q in 9 of the male-assigned individuals—again matching common patterns observed in pre-contact Indigenous American populations. The prevalence of Q aligns genetically with deep founding ancestries that spread across the continents. Taken together, the genetic profile from Jabuticabeira II reinforces archaeological interpretations of long-standing Indigenous occupation of the Atlantic coast and shows direct genetic continuity with broader Native American lineages.

Caveats: the dataset is geographically concentrated to a single site and temporally constrained to 742–1 BCE. While 14 samples offer a substantive sample relative to many coastal sites, regional diversity among sambaquis and later demographic shifts mean these findings should be integrated cautiously into larger models of population history. Future sampling from adjacent sites and time periods will refine patterns of kinship, mobility, and gene flow.