This chapter examines long-term patterns of human mobility, interaction, and adaptation in the Fuegian Andes through an integrated analysis of archaeological, genetic, isotopic, and paleoenvironmental evidence. It explores shifting demographic and cultural dynamics across the Holocene, emphasizing spatial variability in coastal and inland occupation, resource use, and exchange networks among hunter-gatherer-fisher populations. The study highlights significant changes in interaction scales and cultural niche diversity between the Middle and Late Holocene. Evidence suggests that while early populations engaged in expansive networks, later groups experienced more localized interactions, shaped by environmental constraints and social factors. The chapter challenges static ethnographic projections and underscores the complexity of human responses to environmental and demographic shifts, advocating for a nuanced understanding of cultural diversity and resilience in southern Tierra del Fuego.