Evidencia glacial y paleoecologica de ambientes tardiglaciales y del Holoceno temprano. Implicaciones para el poblamiento temprano de Tierra del Fuego

Citation

McCulloch R & Morello F (2009) Evidencia glacial y paleoecologica de ambientes tardiglaciales y del Holoceno temprano. Implicaciones para el poblamiento temprano de Tierra del Fuego. In: Salemme M, Santiago F, Alvarez M, Piana E, Vasquez M & Mansur E (eds.) Arqueologia de la Patagonia: un mirada desde el ultimo confin. Ushuaia, Argentina: Editorial Utopias, pp. 119-134.

Abstract
Human migration across Fuego-Patagonia during the late-glacial and early Holocene takes place against a backdrop of rapid climate change.  To understand the nature and timing of human activity at this time it is essential to reconstruct the sequence of environmental changes as the global ocean-atmosphere system switched from glacial to inter-glacial mode.  Against this backdrop we assess the nature and timing of pathways of opportunity for the southward migration of early people into Fuego-Patagonia.  A synthesis of high resolution glacial and vegetation records suggests that the Fuego-Patagonian glaciers persisted and even re-advanced between c. 12,600 and 10,300 14C yrs BP.  This phase conincides with the Antarctic Cold Reversal but is in contrast to the early deglaciation of northern Patagonia after c. 14,500 14C yrs BP.  The early Holocene (c. 10,300 to 8,200 14C yrs BP) is dominated by an extreme arid phase followed by the return of more humid conditions at c. 8,200 14C yrs BP, as the westerlies returned to their present location.  It is hypothesised that substantial glacio-fluvial barriers limited the early movement of people onto Tierra del Fuego until a window of opportunity existed during the late-glacial / Holocene transition.  However, the subsequent early Holocene aridity may have then become the limiting factor.  The return of more humid conditions during the mid- to late-Holocene likely enabled the increase and dispersal of people as identified in the archaeological record.