Palaeoenvironmental conditions during the Middle Holocene at Isla de los Estados (Staaten Island, Tierra del Fuego, 54° S, Argentina) and their influence on the possibilities for human exploration

Abstract

The Middle Holocene is a particular time period in which there are uneven environmental dynamics all along the southern portion of the continent. Whereas in the Puna, extreme aridity and high temperatures (the so-called " Hypsithermal" period) have been recorded, a more humid and rainy phase dominated southern Tierra del Fuego. The present paper explores the palaeoenvironmental situation of Isla de los Estados (Staaten Island, 54°38'-54°55' S; 63°48'-64°46' W) and its relationship with the archaeological record left behind by ancient canoeing people. The considered period is characterized by exceptionally windy conditions. The palaeoenvironmental information could be used as an explanation for the absence of cultural remains and also for the scarce archaeological record for Península Mitre. At the beginning of the Middle Holocene, the diatom record shows a large amount of . Aulacoseira sp that could indicate either windy conditions or higher water levels at the site core. The more distinctive changes in the diatom assemblages occurred at ca. 5000 cal B.P., suggesting a shallower water level and more acidic conditions. By 3000 cal B.P., the diatom species are strongly linked to peat and swampy environments. However, during the late Holocene, milder conditions might have favored seasonal travelling to the outer islands of the Fuegian Archipelago, though no definitive or permanent settlements have been found.