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Stable isotopes of nitrogen (δ 15N) provide information that can be used to calculate, in a quasi-continuous manner, the trophic position (TP) of organisms within particular food webs. The estimation of the TP is fundamental to analyze cases in which some degree of omnivory is involved. Humans, as a species, are trophic omnivores that use plant and animal tissues as food sources, although in an intraspecific context they tend to significantly vary in their respective degree of omnivory. In archaeology, the use of stable isotopes to infer past diets is widespread; however, the formal assessment of TP is rare. In this paper we describe a method to simultaneously calculate and map the TP of past human populations across large spaces, involving wide environmental variation. This method uses, as inputs, δ 15N isoscapes corresponding to (i) primary producer/s, (ii) a taxon of primary consumers with wide spatial distribution and (iii) humans. The first two isoscapes function as the needed baselines for TP calculation. The approach is exemplified with data from central and southern Argentina and Chile (southern South America, 30°–56° S). [ABSTRACT FROM AUTHOR]

In this paper we present and assess human isotopic data (δ13C and δ15N) available for Southern Chile. We analyze 24 cases from six different geographical zones, dated 200-1850 AD. This new information allows us to characterize individuals who had different subsistence patterns, social organization and historical trajectories, vis-a-vis phenomena like the adoption of ceramics (150 BC), cultigens (750-1000 AD) and the arrival of Europeans (1550 AD). This is complemented by a regional baseline of 45 archaeological faunal and plant resources. Based on our results, three dietary patterns can be identified over time (from 1000 to 1850 AD): one oriented towards marine resources, another towards C 3 plants and terrestrial protein, and the last focused on a mixed consumption of C 3 and C 4 plants, complemented by intake of terrestrial and marine protein. These cases show significant intra-zone consistency over time, and high inter-zone variability. This heterogeneous situation is evident even in synchronous individuals ascribed to the same cultural-historical unit or inhabiting the same geographical macro-zone (valley, coast, islands). It also contrasts with results from adjacent areas to Southern Chile. This highlights the complex diet variability that existed in societies which otherwise appear to be extremely alike in their archaeological record (burials, pottery) and ethnographic features (language, rituals). [ABSTRACT FROM AUTHOR]

Research on the Late Intermediate Period (AD 900–1450) in northern Chile has been strongly influenced by two mobility models: John Murra's classic vertical ecological archipelago model, with highland colonies in the lowlands; and the gyratory mobility model, with pastoralists and their llama caravans controlling trade. The widespread application of these two models, however, suffers from a lack of supporting archaeological evidence. Stable isotope analysis provides a more direct approach for studying both diet and mobility patterns, complementing material culture studies. The aim of this paper is to evaluate the presence of colonies and/or specialised highland caravans in the lowlands of northern Chile through the application of δ13C, δ15N and δ18O to human tooth enamel, bone collagen and bone apatite. The results show strong local traditions in terms of diet and mobility associated with the Loa-San Pedro, Antofagasta and Pica-Tarapacá cultural groups. Our results suggest a non-local origin for some individuals in Pica-Tarapacá and Loa-San Pedro, but provide little evidence to support either the presence of 'colonies' or of specialised 'caravans'. Mobility patterns were, instead, diverse and flexible, including female and male individuals that moved at different moments of their lives. [ABSTRACT FROM AUTHOR]

Camelid caravans have played a key role in the complex systems of interregional social interaction that characterizes Andean history. In the northernmost region of Chile, the most frequent archaeological indicators of these caravan systems are trails and rock art images. Cruces de Molinos (LL-43), a rock art site in the Lluta valley, 1100 masl, 40 km from the Pacific littoral, expands the ceremonial role of rock art sites, materialized, not only as regards the iconography portrayed and alluding to these practices, but also in terms of articulated carcass remains and detached anatomical units of camelids, intentionally deposited in a cache beneath one of the engraved blocks. This paper analyzes the site considering the visual imagery, spatial location, archaeological deposits and features associated with rock art. Based on the predominance of camelid and caravan motifs in rock art images, the extraordinary setting and location of the site on the valley's upper slopes, which is far removed from local settlements, but closely connected with a llama caravan trade network linking the chaupiyunga ecozone with the highlands (sierra and Altiplano ecozones), we suggest that Cruces de Molinos was not a rest stop for caravanners, but a ceremonial place, and not for local farmers, but for highland herders. According to seven accelerator mass spectrometry (AMS) dates that place the occupation between cal. 1060–1190 CE in the Late Intermediate period. [ABSTRACT FROM AUTHOR]

In this paper, we discriminate the contribution of the different sediment sources into a river situated in the semiarid region of northern Chile, differentiating the ones driven by the paraglacial response from the ones yielded to the tributary-junction alluvial fans or the ones coming from the hillslopes. The sedimentary infilling is accurately described in the main landforms such as alluvial fans, alluvial terraces and landslides in the current valley floor where twenty-six 14 C AMS samples were picked up. The 14 C age data indicate that the aggradation in the uppermost part of the valley immediately postdates the glacial retreat at ∼15,000 14 C years cal. B.P. and spans the whole Holocene starting at 11 ka. B.P. and finishing about 2 ka B.P. The main sources for lateral inputs are debris flows from tributary catchments in the portion where the river is embedded in between 1000 and 2000 m a.s.l as well as catastrophic landslides. Additionally, an extensive detailed geomorphological mapping is provided to discuss the meaning of the ages together with an assessment of where the samples came from. Finally, the dataset and field criteria provided in this work contribute to better perform paleoclimatological interpretations for the semiarid fluvial systems of northern Chile. These interpretations usually consider the increased influence of the westerlies during the Holocene and the span of time that the paraglacial response delivers glacigenic sediments into the system. [ABSTRACT FROM AUTHOR]

Ultima Esperanza is a region known worldwide, where some of the best preserved remains of late Pleistocene ground sloths were found. Cueva del Milodón produced a large piece of Mylodon darwini skin in 1895 as well as extensive deposits of ground sloth dung that were sampled several times during the 20th Century. These deposits are dated within 13,500 and 10,200 radiocarbon years. At Cueva del Medio, not far from Cueva del Milodón, evidence of human exploitation of extinct fauna was discovered. Also, at nearby Dos Herraduras rockshelter, several ground sloth elements were found within a tephra layer regionally dated ca. 12,600 BP. This paper presents new data derived from stratigraphic work at Cueva Chica, a site located near Cueva del Milodón, which in spite of its obvious potential was not studied previously. The work revealed more than one layer of Late Pleistocene fauna, where remains of ground sloth, a large felid and other species were preserved. Radiocarbon studies produced some of the oldest evidence for the presence of Mylodon sp. in the region. The integration of these results within the context of the paleoecology of Late Pleistocene Ultima Esperanza is presented. [ABSTRACT FROM AUTHOR]

Abstract: This paper is focused on the history of taphonomically relevant observations made on the deposits of the Cueva del Milodon, Ultima Esperanza, Chile. Taphonomic information was obtained in written accounts by travellers and explorers, as well as in published research reports. Observations made on carnivore marks, trampling marks and other taphonomic markers on ground sloth bone and dung collected at the site are also used. The large size of the cave makes it particularly useful to discuss variation in the distribution of stratigraphic deposits with different preservational properties. A pattern of decreasing preservation of bone and dung from the southern to the northern extremes of the cave was identified. [Copyright &y& Elsevier]

Abstract: Late Glacial and Holocene soils and sediments in southern Chile contain an important record of explosive volcanic activity since the end of the last glaciation, and have considerable potential for the development of a regional tephrostratigraphical framework. This paper reports the discovery of several new tephra deposits from the Hualaihue region (∼42° S) of southern Chile. Eruption sizes, constrained from field observations, and ages, constrained by 25 new radiocarbon dates, show that the volcanoes of the Hualaihue peninsula have had relatively few explosive, tephra-generating eruptions during the Holocene. An eruption of Apagado deposited ∼1 km3 of bedded basaltic scoria at ∼2.6 calibrated (cal) ka BP, and Hornopirén produced a similar, but volumetrically-smaller unit at ∼5.7 cal ka BP. Activity at Yate over the same time period has been predominantly characterised by lava production, although small explosive eruptions, the products of which span a range of compositions, have also occurred, including one at ∼0.9 cal ka BP. The northern part of the regional tephra sequence is dominated by andesitic pumice fall deposits derived from Calbuco volcano. These include deposits from several eruptions during a 3500-year-long period at the start of the Holocene, as well as two large explosive eruptions in the past 2000 years. A distinctive rhyolitic tephra layer that is interbedded with the locally derived tephra sequence is the Cha1 unit, from Chaitén volcano, 108 km south of Hornopirén. This rhyolitic pumice deposit, dated at ∼9.75 cal ka BP, is the largest volumetrically of those described here, with a volume of 3.5 km3. This new tephrostratigraphy covers a region whose volcanic history was previously very little known, and contributes to a regional record of large explosive eruptions that now spans a 500 km-long segment of the southern Andean arc, between Calbuco and Hudson volcanoes. [Copyright &y& Elsevier]

Abstract: While the Ensenadan Stage/Age (ca. 2.1 to 0.5Ma) was characterized by certain mammal associations in the Pampean plains, the Andean ranges of Patagonia and Tierra del Fuego, their piedmont areas and, in some cases, the adjacent lowlands were undergoing a well-defined alternating sequence of glacial and interglacial stages driven by the regional climate of Southernmost South America and Antarctica. This paper reviews the available geographical, geological and chronological evidence of glaciation during the Ensenadan stage/age, with perhaps more than 15 distinct glacial events, including the Great Patagonian Glaciation (GPG) and other cold episodes that took place before and after it. Finally, a tentative correlation of Patagonian glacial episodes and the Pampean biostratigraphic stages, based on radiometric dating and paleomagnetic studies, is herein presented. [Copyright &y& Elsevier]