La Arcillosa 2 — North Tierra del Fuego

La Arcillosa 2 sits on the northern shores of Tierra del Fuego, a wind‑scraped landscape where ocean and rock meet. Radiocarbon-calibrated dates place the human material between 4040 and 3710 BCE (roughly 5800 years before present), anchoring this individual in the Late Holocene coastal world of southern South America. Archaeological data from the broader Fuegian littoral indicate repeated use of shorelines for food and raw materials; shell middens, hearths, and small lithic scatters are characteristic of sites in this region, although preservation varies.

Limited evidence suggests that the people who occupied these coasts were highly mobile, moving seasonally to exploit fish, shellfish, seabirds, and marine mammals. The singular nature of the La Arcillosa 2 genetic sample means cultural attribution must be cautious: while the find aligns chronologically with other Late Holocene coastal foragers in the southern cone, specific material culture links to named archaeological traditions are provisional. Still, the presence of a human lineage here at ~5800 BP provides a powerful temporal anchor for understanding human persistence in extreme southern latitudes and frames questions about mobility, exchange, and environmental adaptation that archaeological fieldwork can further test.

Genetic analysis of the single La Arcillosa 2 individual recovered mtDNA from haplogroup C. Haplogroup C is one of the maternal lineages broadly present among Indigenous populations across the Americas and is known in ancient and modern contexts throughout South America. The mtDNA result indicates that the maternal ancestry of this individual falls within the deep genetic diversity that accompanied the initial peopling and subsequent regional differentiation of Native American populations.

However, the genetic picture is extremely limited: there is only one sample from La Arcillosa 2. When sample counts are below ten, inferences about population structure, migration routes, or continuity with later groups must be treated as preliminary. No Y‑chromosome (paternal) haplogroup is reported for this individual, so paternal lineages remain unknown. Integrating this mtDNA result with broader ancient DNA datasets from the southern cone can suggest hypotheses—such as maternal continuity or regional isolation—but confirmation requires more genomes. Future shotgun sequencing, higher coverage mitochondrial genomes, and additional individuals from La Arcillosa and nearby sites will be essential to resolve whether this mtDNA C instance reflects local continuity, a wider coastal maternal lineage, or population turnover events.