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This paper describes a petrified trunk collected from a conglomerate bed of the Springhill Formation (Berriasian-Valanginian) in the Estancia El Álamo locality, Santa Cruz Province, Argentina. The fossil trunk is classified within the ubiquitous genus Agathoxylon and the wood anatomy shows a close affinity to that of Araucariaceae. This Patagonian wood has a distinct combination of anatomical characteristics unique among all known species from the Jurassic and Cretaceous of Western Gondwana allowing to diagnose a new fossil taxon Agathoxylon mendezii sp. nov. Sedimentological and megafloristic proxies of the Springhill Formation suggest that Agathoxylon mendezii sp. nov. grew under a warm and wet climate, which indicates a subtropical to temperate palaeoenvironment. However, the large number of frost rings in the earlywood of this araucarian tree suggests that the palaeoenvironment at Estancia El Álamo was subjected to recurrent disturbances, most likely caused by regional continuous volcanic activity originating from volcanoes located far away to the west. This activity would have produced periodic stratospheric veils that promoted rapid decreases in surface air temperature; the wood response to such stressful conditions would have been the formation of numerous (at least five) frost rings. Although recurrent eruptions in Patagonia during the Early Cretaceous are well recorded, this study is the first to register eruptions recorded in a coniferous wood. [ABSTRACT FROM AUTHOR]

This paper describes a petrified trunk collected from a conglomerate bed of the Springhill Formation (Berriasian-Valanginian) in the Estancia El Álamo locality, Santa Cruz Province, Argentina. The fossil trunk is classified within the ubiquitous genus Agathoxylon and the wood anatomy shows a close affinity to that of Araucariaceae. This Patagonian wood has a distinct combination of anatomical characteristics unique among all known species from the Jurassic and Cretaceous of Western Gondwana allowing to diagnose a new fossil taxon Agathoxylon mendezii sp. nov. Sedimentological and megafloristic proxies of the Springhill Formation suggest that Agathoxylon mendezii sp. nov. grew under a warm and wet climate, which indicates a subtropical to temperate palaeoenvironment. However, the large number of frost rings in the earlywood of this araucarian tree suggests that the palaeoenvironment at Estancia El Álamo was subjected to recurrent disturbances, most likely caused by regional continuous volcanic activity originating from volcanoes located far away to the west. This activity would have produced periodic stratospheric veils that promoted rapid decreases in surface air temperature; the wood response to such stressful conditions would have been the formation of numerous (at least five) frost rings. Although recurrent eruptions in Patagonia during the Early Cretaceous are well recorded, this study is the first to register eruptions recorded in a coniferous wood. [ABSTRACT FROM AUTHOR]

Well-preserved and diverse Early Cretaceous palynological assemblages were studied from an outcrop section of the Springhill Formation at the Río Correntoso locality (PRC), close to Ghío Lake, in Santa Cruz Province, Patagonia, Argentina. The studied log corresponds to the northernmost outcrops known for the Springhill Formation in the Austral Basin. Most of the palynomorphs algae (Botryococcus, Sphaeroplea, Lecaniella, Zygnema, Pseudoschizaea, Schizosporis, Ovoidites), and some angiosperm pollen grains (Proxapertites , Longapertites, Arecipites) are distinctive and characterize the palaeoenvironment and palaeoclimate of PRC, which was dominated by estuarine coastal margin sedimentites deposited under warm and humid conditions. These angiosperm pollen grains correspond to the earliest record of these group in Patagonia, represented by diverse monosulcates and one rare tricolpate type. This new record of angiosperm pollen in the Springhill Formation provides further evidence that one of the earliest diversifications of angiosperms started at least during the early Cretaceous in Patagonia. Sergio Archangelsky provided an invaluable expertise in the field of paleobotany in multiple ways. His knowledge transcended not only through his papers but also through his exceptional oratory skills. His talks were always enriching in every aspect, combining an engaging historical account with a vision towards the future. "...La paleobotánica un placer, debe ser algo agradable, es decir uno cuando trabaja en paleobotánica le gusta lo que hace, y cuando uno está describiendo, uno se va, y es lo mismo que componer una pieza musical, te perdés, te perdés en todo y lo hacés con gusto, con pasión..." "...The paleobotany is a pleasure, it should be something enjoyable, meaning that when you work in paleobotany, you love what you do. And when you're describing, you get lost, just like composing a musical piece. You lose yourself, in everything, and you do it with pleasure, with passion...". The file with the voice of Sergio Archangelsky is in Supplementary file under Sergio_Archangelsky.mp3. • The palynoflora of the Springhill Formation includes algae and land plants. • Pollen records show features of early members of some taxa (monocots and eudicots). • Angiosperm pollen grains provides evidence for early radiation of some basal taxa in Patagonia. • Palynoflora studied indicates freshwater palaeoenvironment, warm and humid climate. [ABSTRACT FROM AUTHOR]

In this paper, the analysis of a radiocarbon database of the North Coast of Santa Cruz (central Patagonia, Argentina), is presented. Dated archaeological samples were obtained from 56 different types of archaeological sites (open-air -residential sites and burials-, and also rock shelters). The objective of this paper is assessing the continuities and discontinuities in the chronological signal of the area and identifying tendencies along the Holocene. The database currently contains 75 radiocarbon dates falling between ca. 8000 and 300 BP. The radiocarbon data base provides information on the chronological, spatial and contextual variability of the archaeological record of North Coast of Santa Cruz. By means of different analysis of sum of probabilities, we present three different chronological moments of human use of the coast and intermediate zone can be identified. A first moment is represented by early evidence of settlement during Middle Holocene. A second moment corresponds to a hiatus between ca. 5800 and ca. 3900 BP without archaeological evidence. Finally, a third moment is where an increasing of chronological signal occurred, related to greater artifactual variability and an increase in the intensity of human settlement in the Patagonian region. The causes that could have influenced in the discontinuity of the chronological signal of the study area, and the characteristics of the different moments identified are discussed. [ABSTRACT FROM AUTHOR]

Abstract: This paper compares two zooarchaeological sub-samples, each of which comes from a different area (North chamber and South chamber) of Maripe Cave Site (Santa Cruz, Argentina). In previous papers, each chamber was interpreted as a particular microenvironment based on their specific environmental and geoarchaeological features. In both areas, hunting–gatherer society occupations were recorded since the Pleistocene–Holocene transition to late Holocene. This paper investigated and discussed the different agents and processes involved in the formation of each assemblage, with the aim of assessing the taphonomic variability between the two areas and discussing their integrity. Bone specimens of Lama guanicoe (guanaco), the most common species on the site, were analyzed. The bone surfaces of specimens were studied by naked eye observations and binocular magnifying to 10×, which allowed recognition of different patterns of modification. The representation of guanaco anatomical units was also discussed at each chamber according to economic utility and BMD values. The results indicate that while there was involvement of different natural agents and processes acted differently in each sector, the main accumulating agent in both sets was human. Differences between both chambers are observed in the representation of anatomical units, in processing marks, in the conservation of specimens, and in the number and intensity performed by each natural agents and process in each sector. Each chamber indicates a different taphonomic history: the North Chamber records greater conservation and archaeological integrity, while the South Chamber shows a more complex taphonomy. [Copyright &y& Elsevier]

Abstract: In the Deseado Massif there are many stratified archaeological sites located in caves and rockshelters. The cultural sequences, proposed in the past century, include an occupational hiatus and cultural changes that were developed on the basis of large tools from archaeological sites, without debitage analysis. The aim of this paper is to review the current debate on lithic technology and human occupations of this area during the Mid-Holocene, integrating new data, as well as the latest environmental interpretations. The contribution of new information from blade and bifacial technologies is central to discussion of the models proposed by other authors. The new baseline information generated in the last decade, allow original interpretations. The evidence of coexistence between blade and bifacial technologies during the Mid-Holocene constitutes the main contribution of this paper. [Copyright &y& Elsevier]

This paper discusses provisioning strategies of lithic raw materials at Maripe Cave site (province of Santa Cruz, Argentina). The archaeological sequence represents different moments of human occupation at the cave and in the study area, which show different lithic technologies. The morpho-typological analysis of the lithic cores recovered contributes to our knowledge about the strategies related to procurement and provisioning of the lithic raw materials used for artifacts production. We identified different raw materials from the analyses of lithic cores and other artifacts from the site. This allowed analyzing trends in selection and provisioning processes and interpreting the mobility strategies of the groups that inhabited the Deseado Massif since the Pleistocene–Holocene transition. Trends suggest that, during the Pleistocene–Holocene transition and early Holocene, abandoned cores from Maripe Cave mainly indicate people provisioning strategies. During middle Holocene, the cores shows blades extractions and raw material use from long distance, discarded with remaining potential utility. Finally, at late Holocene the cores were mainly prepared for blade extractions. Our results do not fully agree with Kuhn's proposal, probably due to both the theoretical polarization between the provisioning strategies and the palimpsest effect. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to begin to understand human mobility through rock transport at different times in two areas with different environmental characteristics: the Southern Deseado Massif and the basaltic canyons north of the Santa Cruz River. We focus on obsidian, which has a clear geochemical signature and an uneven distribution. Additionally, we use macroscopic information on siliceous rocks, which at present have only been identified in northern areas, although they may also be recovered randomly and in low frequencies in southern ones. During the initial peopling of the Southern Deseado Massif (ca. 10,800 BP), inhabitants were transporting black obsidian as well as translucent chalcedony, probably as part of the individual gear. During the Late Holocene, the number of obsidian artifacts decreased in the Southern Deseado Massif, related to a better knowledge of the high-quality local lithic resources and/or to the existence of higher population densities. Obsidian artifacts are more abundant in the northern Santa Cruz River basin than in the southern Deseado Massif, suggesting the existence of a relationship with areas located to the northwest, close to the obsidian source, as other lines of evidence suggest. In addition, the presence in the basaltic canyons of artifacts made from high-quality siliceous rocks, more abundant and predictable in northern areas, could also be the result of human movements following a north-south direction. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the reconstruction of the previously undocumented Meseta Cuadrada palaeo ice cap on south-west Meseta del Lago Buenos Aires, Santa Cruz Province, Patagonia. Based on theoretical surface profiles the reconstruction of the Meseta Cuadrada Palaeo Ice Cap indicates an ice mass covering at least 78km2 with a total ice volume around 9.2km3. The inferred equilibrium line altitude (ELA) of the palaeo ice cap (2031m asl) represents a drop of 286m compared to the ELA of the current Meseta Cuadrada glacier (~2317m asl). We explain this small change in ELA with reference to the flat hypsometry of the palaeo ice cap and an enhanced aridity to the west of the Patagonian Andes caused by the existence of the Last Glacial Maximum (LGM) Patagonian ice sheet. Calculated annual accumulation values of ca. 402 to 957mm/a at the ELA of the Meseta Cuadrada palaeo ice cap derived by a degree day model (DDM) during the last local glacial maximum extent are low compared with estimations of the current accumulation at the ELA of the remaining glacierized area of around 3789mm/a. This strongly supports the existence of increased aridity and seasonality east of the Patagonian Andes during the Last Glacial Maximum, provided both maximum extents were synchronous. [Copyright &y& Elsevier]

In Argentina, teachers have traditionally been characterized as part of the middle class or the petty bourgeoisie, depending on the theoretical perspective. This characterization is usually based on the predominantly female composition of teachers as a group and on their character of wives of that portion of the population that occupies "relatively important positions in the social structure". However, few studies have attempted to account for this hypothesis and most of them are based on unrepresentative samples. In this paper we present an exercise based on a comparison of census data for three jurisdictions which have different features both in the recruitment of teachers and in their specific social and economic structures: Ciudad de Buenos Aires, La Pampa and Santa Cruz. [ABSTRACT FROM AUTHOR]

This paper reports the pollen sources selected by Apis mellifera in the area northwest of Santa Cruz (Argentina). It evaluates the relative biomass contribution and the protein content of the collected taxa. During the apicultural period (September 2008-March 2009) pollen loads from three colonies were collected every fortnight using pollen traps. Forty-two pollen types were found in the samples, from which 15 taxa had a biomass contribution over 1% of the total pollen crop. The main pollen sources were Brassicaceae, Taraxacum officinale, Convolvulus arvensis, Rosaceae, Salix spp. and Schinus marchandii (Anacardiaceae). Of the total pollen sources identified, 15 are new records for the bee pollen flora of Argentina and 13 are native plants of South America. The contribution of native flora occurred mainly in spring. Schinus marchandii, Mulguraea-Junellia type (Verbenaceae), Adesmia spp. (Fabaceae), Sysirinchium spp. (Iridaceae), Acaena spp. (Rosaceae), Astereae and Senecio spp. (Asteraceae) were the indigenous pollen types with the highest biomass contribution. Protein content of most collected pollen types was variable (between 13.25% and 24.43%). [ABSTRACT FROM AUTHOR]

Based on a series of audiovisual experiences undergone in the city of Caleta Olivia in the Santa Cruz Province in Argentina (including the Chilean community), this paper analyzes how the discourse on crisis and its development contribute to the support of differing opinions among the citizenry, by constructing imaginary borders and conforming representations of the other. The reception of this discourse, from a video with fragments from a local television program from the Chilean community, answered the following questions: Which representations from the Caletense society are shared by Chileans when decoding these messages? How is the cultural heterogeneity of Caleta Olivia narrated? exactly how are these television discourses appropriated in order to sustain and challenge the national and regional identities, re-elaborating in this manner their own chilean identity. [ABSTRACT FROM AUTHOR]