The Pleistocene and Holocene times were characterized by frequent latitudinal and altitudinal changes in the vegetation distribution, as a response to recurrent climatic oscillations, fluctuations of sea level and ice extent and changing patterns of atmospheric circulation. Palynological records from the Early and Middle Pleistocene are, however, scarce and discontinuous and this makes the recognition of the boundaries between palaeophytogeographic provinces difficult. Only one pollen fossil record is available for the Middle Pleistocene, which comes from a location at 50°S (the Cañadón El Mosquito site) in the Patagonian semi-desertic area of the upper Río Santa Cruz valley (Schäbitz & Schellmann, 1999). The record probably belongs to an interglacial period (c. 430 ka B.P.; i.e. MIS 11) and suggests that the palaeovegetation was dominated by a dense forest of mainly Podocarpus accompanied by lesser amounts of Nothofagus, N. obliqua-type and Cupressaceae, developed under more humid and warmer climate than today (Mancini et al., 2008). In the eastern Fuegian Archipelago, the landscape was during the Middle–Late Pleistocene, probably MIS 4 or even perhaps reaching up to MIS 6 (39 560 to > 58 000 years B.P.), dominated by steppe/tundra environments. This landscape reflects drier and colder conditions than today (Bujalesky et al., 1997), probably corresponding to a stadial period. In extra-Andean Patagonia, at the Magallanes maar core (52°S), the vegetation pattern reflects a grass steppe under colder and more humid conditions than today during the MIS 3 interstadial (31 560 to > 51 700 years B.P.; Corbella, Borromei & Quattrocchio, 2000). Likewise, the fossil pollen record from western Patagonia at the Bajada de Rahue sequence (39°S) indicates the development of steppe–scrub vegetation that suggest precipitation and temperature similar to the modern one during the MIS 3 interstadial (27 900–32 600 years B.P.) (Markgraf et al., 1986). After the Last Glacial Maximum (LGM; c. 24 cal. ka B.P.; Rabassa, 2008c) the palynological data indicate variations in temperature and precipitation under global increasing temperature trend (McCulloch et al., 2000; Pendall et al., 2001). The pollen records from east of the Andes in Patagonia and from southern Tierra del Fuego show, with only minor local differences, a postglacial vegetation dominated by steppe/shrub/heath communities. The palaeoenvironments were drier and colder than present day conditions to the point of reduction of Nothofagus forest in the Andean areas. These climate conditions throughout the higher southern latitudes suggest that the southern limit of the westerly storm tracks was positioned equator-wards, and/or was substantially weaker than today (McCulloch & Davies, 2001; Markgraf & Huber, 2010). During the final Late Glacial period (after 12 800 cal. yr B.P.), the Nothofagus forest expanded gradually into the landscape from glacial refuges or niches located in the western regions. During the Early Holocene (11 500–8000 cal. yr B.P.), a Nothofagus forest more open than today spread regionally through the southern Andean Patagonia (Mancini et al., 2008) and southern Tierra del Fuego (Borromei & Quattrocchio, 2008) under conditions warmer and drier than today in an environmental setting subject to high fire incidence (Whitlock, Moreno & Bartlein, 2007) as a result of highly variable westerly precipitation regimes (Markgraf & Huber, 2010). In southern extra-Andean Patagonia, the pollen record from Laguna Potrok Aike (51°S) indicates that the grass steppe was replaced by shrub steppe, suggesting low available moisture in the steppe (Wille et al., 2007). Also, the spread of grass steppe vegetation in the central–north Fuegian region indicates drier conditions (Heusser, 2003). Meanwhile, in northern extra-Andean Patagonia (40–50°S), the pollen data show the development of grass steppe and Patagonian shrubs vegetation (Mancini et al., 2008). The sedimentological and pollen data from the Lago Cardiel record (49°S) also show high lake levels and steppe herbs and scrub vegetation (Markgraf et al., 2003), all as a signal of higher moisture conditions. This climate pattern probably reflects a highly variable position and/or intensity of the westerly winds focused from 46 to 49°S (Markgraf et al., 2003; Villa-Martínez & Moreno, 2007) or the weakening and southward shift of westerlies' storm tracks, probably south of 54°S, along with increased advection of humid Atlantic Ocean air masses to the eastern Andean slopes of central Patagonia (Villa-Martínez & Moreno, 2007; Whitlock et al., 2007). During the Middle Holocene (8000–4000 cal. yr B.P.) the vegetation scenario from the northern and southern Andean Patagonian region and southern extreme of extra-Andean Patagonia (51°S) reflect wetter conditions with the development of Nothofagus forest–steppe ecotone and grass steppe vegetation (Mancini et al., 2008). Also, in southern Tierra del Fuego and western Isla de los Estados, the pollen record indicates more humid and colder conditions than during the Early Holocene, with the development of open forests and Nothofagus forest/Empetrum heath communities, respectively (Borromei & Quattrocchio, 2008; Ponce et al., 2010). Meanwhile, in extra-Andean Patagonia and central–north-eastern Tierra del Fuego, grass–shrub and grass steppes developed, respectively, under semi-arid conditions (Heusser, 2003; Mancini et al., 2008). This palaeoclimate evidence points both to a northward latitudinal change and to the strengthening of the westerlies on the Andean region, leading to low moisture conditions east of the Andes in the area affected by the rain-shadow effect of the Andean Cordillera (Mancini et al., 2008; Borromei et al., 2010). The strengthening of the Southern Hemisphere Westerly Winds (SWWW) by approximately 8000 cal. yr B.P. correlates, within dating uncertainties, with the commencement of neoglacial advances as early as 8.5 ± 0.7 and 6.2 ± 0.8 ka in central Patagonia (46°S) (Moreno et al., 2010; Ponce et al., 2010). The Late Holocene (the last 4000 years) has been characterized as a cooler, wetter period, with renewed glacial activity in the Central Patagonian Andes during the so-called ‘Neoglaciations’ (Mercer, 1976; Moreno et al., 2009). Maximum precipitation levels are recorded in all pollen records from Andean Patagonia (Moreno et al., 2009; Tonello, Mancini & Seppä, 2009) and the Fuegian Archipelago (Heusser, 2003; Borromei et al., 2010), including western Isla de los Estados (Ponce et al., 2010). In the Andean Patagonia and Fuegian region, the vegetation was dominated by closed Nothofagus forests with a net eastward shift of the forest–steppe ecotone, whereas the Subantarctic Evergreen Forest expanded in western Isla de los Estados. This intensification of the westerlies may have been associated with a steepening of the pole-to-equator temperature gradient, caused by a cooling trend in the Southern Ocean and Antarctica (Divine et al., 2010). In extra-Andean Patagonia, arid–semi-arid conditions prevailed, with development of the Patagonian–Monte shrub steppe vegetation. During the last 2000 years, the palaeodata document multi-century variability, apparently reflecting drier conditions during the Medieval Warm Period (MWP) and cooler, moister conditions during the Little Ice Age (LIA) (Mauquoy et al., 2004; Moy et al., 2008; Fey et al., 2009; Moreno et al., 2009; Borromei et al., 2010; Waldmann et al., 2010).