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The Salado and Verde streams constitute the two main seasonally available freshwater courses that flow into the Atlantic coast of the Río Negro province (continental Patagonia, Argentina, 42° South). This would have favored their use in the past as corridors for human circulation between the coast and the interior. This paper presents the results of the technomorphological and geochemical analyses of the obsidian artifacts recovered in the area to constrain mobility. The results allow us to propose the existence of toolkit reconditioning or replacement activities, and the identification of different sources of provenance of the obsidians (Sacanana, Telsen, and Portada Covunco, distant up to 800 km from the study area), reinforcing the hypothesis of a coast–inland circulation, with the possible existence of circuits of exchange of this raw material. [ABSTRACT FROM AUTHOR]

Focuses on the global developments in geology. Discovery of the largest dinosaur remains in Patagonia; Production of a living dinosaur embryo by scientists; Use of the Kosovan communities for the effects of high levels of natural radon.

Bioarchaeological research of bone growth patterns provides information on the health status and disease of past populations. Recent studies have pointed out the potential of metric analysis of nonadult vertebrae as indicators of stress during different stages of ontogeny, highlighting that most vertebral measurements present low sexual dimorphism, a stable and known pattern of growth and give useful information even in incomplete spines. The aims of this paper are first, to construct a vertebral growth profile for nonadults of a skeletal series of Patagonian Late Holocene hunter‐gatherers from Salitroso Lake (SAC); second, to compare it to the ones obtained in other archaeological and modern populations with different stress experiences; and third, building on this, to assess whether individuals with evidence of stress experienced in early development demonstrate different patterns in vertebral growth than those without. Two spinal dimensions are used: vertebral body height (VBH) and transverse diameter of the neural canal (TDNC) in a sample of 23 nonadult skeletons with ages previously estimated from dental and bone indicators. The vertebral dimensions of 20 adults between 18 and 35 years of age were also measured as reference information. Results show that the growth of the VBH is steady over the years and reaches adulthood size by approximately 16 years of age whereas TDNC dimensions do not experience marked fluctuations in size throughout life and adult dimensions are reached at approximately 4 years of age as expected. The vertebral growth pattern observed in SAC is similar to that obtained in other archaeological samples from very different settings but experiencing relatively high nutritional or pathological stress in early stages of life. However, it is markedly different, and systematically smaller, to the 20th century sample pattern, probably responding to a secular trend in the modern population with a more stable access to resources and medical treatment. Finally, SAC individuals with systemic stress markers do not tend to exhibit smaller vertebral dimensions than those without them. [ABSTRACT FROM AUTHOR]

This paper presents for the first time results on winds, tides, gradients of horizontal winds, and momentum fluxes at mesosphere and lower thermosphere altitudes over southern Patagonia, one of the most dynamically active regions in the world. For this purpose, measurements provided by SIMONe Argentina are investigated. SIMONe Argentina is a novel multistatic specular meteor radar system that implements a Spread‐spectrum Interferometric Multistatic meteor radar Observing Network (SIMONe) approach, and that has been operating since the end of September 2019. Average counts of more than 30,000 meteor detections per day result in tidal estimates with statistical uncertainties of less than 1 m/s. Thanks to the multistatic configuration, horizontal and vertical gradients of the horizontal winds are obtained, as well as vertical winds free from horizontal divergence contamination. The vertical gradients of both zonal and meridional winds exhibit strong tidal signatures. Mean momentum fluxes are estimated after removing the effects of mean winds using a 4‐h, 8‐km window in time and altitude, respectively. Reasonable statistical uncertainties of the momentum fluxes are obtained after applying a 28‐day averaging. Therefore, the momentum flux estimates presented in this paper represent monthly mean values of waves with periods of 4 h or less, vertical wavelengths shorter than 8 km, and horizontal scales less than 400 km. Key Points: First observations of mesosphere and lower thermosphere dynamics over one of the most dynamically active regions in the worldEstimates of mean horizontal winds and their gradients are possible, thanks to the multistatic configurationMean momentum fluxes are estimated with vertical velocity estimates free of horizontal divergence contamination [ABSTRACT FROM AUTHOR]

Nowadays, wildlife is one of the most important sources of zoonoses, and it is a major concern for public health. Nevertheless, little is known about the role of wildlife as a reservoir and source of infectious diseases in the past. South America presents a wide diversity of wildlife. In the south of the continent, Argentina shelters a large diversity of neotropical carnivores. Although the paleoparasitological studies on carnivores have been increasing in southern Argentina, most of the efforts have been focused in a handful of sites located in western Patagonia. In this paper, two coprolites of felid found in Cueva Galpón, an initial late Holocene mortuary site from northeast Patagonia (Argentina), were studied for paleoparasitological purposes. Samples were processed by rehydration and homogenization, filtered and processed by spontaneous sedimentation. The samples were assigned to Puma concolor (puma) or Panthera onca (jaguar). Microscopic observations revealed that both coprolites were positive for parasite remains. High parasite richness was observed. Six nematodes, one cestode, and one coccidian morphotypes were reported. This is the first time that Gnathostoma sp. and Spirocerca sp. were recovered from holocenic times from Patagonia. This finding implies that some diseases such as taeniasis, spirocercosis, gnathostomosis, ascariasis, and coccidiosis could be present in holocenic wildlife from Patagonia prior to the Spanish colonization and domestic animal introduction. The overall results suggest that felids could have played a role as reservoirs and source of some parasitic species, some of which are zoonotic. Therefore, this animal could have entailed a risk agent for human health in the site. [ABSTRACT FROM AUTHOR]

This paper presents the first petrographic study of pottery made by hunter–gatherer societies that inhabited the eastern Pampa–Patagonia transition regions (Buenos Aires province, Argentina), between c.1900 and 400 radiocarbon‐years bp. The data show that the potters maintained technical choices during this period as part of a technological tradition. With this common knowledge, local fabric recipes coexisted linked to the regularity of the use of raw materials in accordance with the geology of the research area. Furthermore, the finding of archaeological clay doughs would indicate the in situ production of vessels in the residential contexts of these pre‐Hispanic populations. [ABSTRACT FROM AUTHOR]

In a recently published paper, Oliva et al. concluded that domestic grazing pressure across Patagonian rangelands approached carrying capacity due to decades of stock adjustment, but that guanaco overpopulation may have altered that balance. The authors argued that unless guanaco numbers are controlled, they will reduce forage available for domestic stock and will negatively affect rangelands. We consider that the herbivore‐stock analysis presented is inaccurate and deserves revision, and that the stated conclusions lack empirical support.When the spatial distribution of herbivores is accounted for in the Oliva et al. analysis, domestic stock is far above carrying capacity, indicating that domestic overgrazing continues.Theoretical and empirical evidence on bottom‐up regulation and competitive exclusion challenges the supposed guanaco overpopulation and the hypothetical reduction of forage available for livestock.Even if guanaco numbers are reduced, grassland degradation and production losses will continue because their main drivers, domestic overstock and heterogeneous grazing, are still operating.Synthesis and applications. Oversimplified models with poor ecological insight can lead to erroneous conclusions and misguide management decisions. The incorrect inference that Patagonian domestic stock is adjusted to carrying capacity could help to consolidate current domestic overgrazing by reducing incentives to improve livestock management practices. Regarding guanacos, a controversial species in an unfavourable context, control‐oriented harvest without a clear justification threatens populations' viability and genuine attempts of productive diversification. Addressing relevant ecological processes, such as niche partitioning, competitive exclusion and population regulation, is essential to correctly assess joint carrying capacity in multi‐herbivore systems, as well as to identify the true factors driving degradation processes and to optimize rangeland use on a sustainable basis. [ABSTRACT FROM AUTHOR]

This study focuses on Patagonia, where Foehn events observed in the lee of the Andes mountains are not yet well simulated by state‐of‐the‐art climate models. It has been agreed that one source of this shortcoming is related to the poor relief representation in models. To resolve this need, a common method used is to enhance the spatial resolution of the model to retrieve a more complex surface elevation, at the expense of calculation time or surface area covered. This paper tackles the problem from a different angle by addressing the Digital Elevation Model (DEM) generalization, that is, the altitudes generalization from a high‐resolution DEM to a coarser resolution grid model. Most current climate models use DEM generalization methods that smooth the relief, a key controlling factor in Foehn events modelling. The aim of this study is to compare three original methods of DEM generalization (percentile 90 [P90], envelope maximum [EM], and thalweg and crests [TC]) and to evaluate their impact on simulated precipitation and temperature fields on the eastern part of Patagonia, where warm and dry air masses are expected. Thanks to MAR, a Regional Climate Model, we validate the models at 10 and 5 km resolutions against the Climate Research Unit and perform three sensitivity experiments involving a change in the DEM generalization. Our results show that (a) a finer spatial resolution can slightly improve the temperature biases, however, it cannot resolve the precipitation biases and (b) a more appropriate use of DEM generalization induces a significant decrease in precipitation for the P90 and EM methods and an increase in mean temperature for all three methods in the study area. This study serves as a recommendation for a better use of DEM generalization in climate models performing in Patagonia, but also regions sharing the same orographic features as the Patagonian relief. [ABSTRACT FROM AUTHOR]

In 1995, an almost complete human skeleton was found in Punta Cuevas, in the southern coast of Puerto Madryn, Chubut, Argentina. The burial traits and the associated objects suggested the skeleton might belong to Mrs. Catherine Roberts‐Davies, a middle‐aged woman who was the first dead person among the first group of 163 Welsh settlers that set sail on May 28, 1865, from Liverpool to Bahía Nueva, in Argentinian Patagonia. The aim of this paper is to present the interdisciplinary studies conducted between 1995 and 2016 in order to identify these remains and to explore the possible causes of death. The age at death of the skeleton was estimated between 25 and 40 years old and sexed as female. The analyses of mtDNA haplogroup resulted in K2a, which is highly frequent in European populations. An ascendant maternal genealogy of Mrs. Roberts‐Davies was reconstructed, based on documentary sources. After this genealogical research, a living descendant, who currently lives in Wales, was found. An mtDNA analysis of control region 16024‐576 was compared among samples taken from the unknown skeleton and the descendant. The results confirmed that the skeleton found in Punta Cuevas belongs to Mrs. Catherine Roberts‐Davies. With respect to the cause of death, according to two historical medical reports, Mrs. Roberts‐Davies died from "black fever" (i.e., visceral leishmaniasis) or scurvy. Skeletal evidence suggests that she could have suffered from scurvy as a consequence of the harsh conditions of living during the trip from Liverpool and the first days after the arrival to Patagonia. [ABSTRACT FROM AUTHOR]

Across the extreme south of Patagonia, the Magallanes‐Fagnano Fault (MFF) accommodates the left‐lateral relative motion between South America and Scotia plates. In this paper, we present an updated view of the geometry of the eastern portion of the MFF outcropping in Tierra del Fuego. We subdivide the MFF in eight segments on the basis of their deformation styles, using field mapping and interpretation of high‐resolution imagery. We quantify coseismic ruptures of the strongest recorded 1949, Mw7.5 earthquake, and determine its eastern termination. We recognize several co‐seismic offsets in man‐made features showing a sinistral shift up to 6.5 m, greater than previously estimated. Using 10Be cosmogenic nuclides depth profiles, we date a cumulated offset in post‐glacial morphologies and estimate the long‐term slip rate of the eastern MFF. We quantify a 6.4 ± 0.9 mm/a left‐lateral fault slip rate, which overlaps geodetic velocity and suggests stable fault behaviour since Pleistocene. [ABSTRACT FROM AUTHOR]

Carrying capacity is the maximum animal density an area can sustain without deterioration of its resources. Overgrazing has degraded Patagonia, but sheep stocks decreased and gave way to mixed systems with cattle, goats and guanacos (native wild camelids).The objective of this paper was to develop a method to estimate the carrying capacity based on the remotely sensed data, and to assess wild and domestic herbivore numbers in order to establish if grazing stocks have evolved to balance with carrying capacity.Net Primary Productivity (NPP) MOD17/A3 images and field Aerial Net Primary Productivity (ANPP) data of 66 sites were linearly regressed (R2 = 0.83, p < 0.01), and the slope 0.236 used to convert MOD17/A3 NPP to ANPP. Harvest index (proportion of ANPP that may be sustainably consumed) was estimated as a function of ANPP and carrying capacity as a consumable forage/estimated annual consumption, set at 500 (sheep and goats), 3,200 (cattle) and 750 kg Dry Matter head−1 year−1 (guanacos).Regional ANPP ± SD (2000–2015) was 758 ± 52 kg Dry Matter ha−1 year−1 and Harvest index was 13.7 ± 0.6%. Regional carrying capacity was 14.8 ± 1.6 M sheep or goats, 2.3 ± 0.3 M cattle or 9.9 ± 1.2 M guanacos.Domestic stock was high from 1920 to 1980, but declined thereafter and remained mostly within 1 SD of mean 2000–2015 carrying capacity. In this century, annual provincial stocks and carrying capacity correlated well (R2 = 0.94, p < 0.01) with a slope close to 1.Guanacos increased from 0.5 to 2 M between 2000 and 2015, driving linearly combined grazing pressures 36% and 62% above carrying capacity in southern Patagonia provinces in 2015.Synthesis and applications. From the year 2000, after decades of sheep overstocking, domestic stock has shown a regional trend towards a grazing equilibrium, but growth of guanacos might have upset that trend. Participation of guanacos as a critical excess in total grazing pressure is debatable, but management of these populations is necessary and may be increasingly attractive if combined production systems are developed to incorporate wild meat and fibre. Our method, MOD17/A3 enables a carrying capacity evaluation and stock adjustment in these unique mixed grazing systems, preventing further rangeland degradation and loss of ecosystem services. From the year 2000, after decades of sheep overstocking, domestic stock has shown a regional trend towards a grazing equilibrium, but growth of guanacos might have upset that trend. Participation of guanacos as a critical excess in total grazing pressure is debatable, but management of these populations is necessary and may be increasingly attractive if combined production systems are developed to incorporate wild meat and fibre. Our method, MOD17/A3 enables a carrying capacity evaluation and stock adjustment in these unique mixed grazing systems, preventing further rangeland degradation and loss of ecosystem services. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the results of the analysis of a gunflints sample from two Colonial archaeological sites located in Patagonia (Argentina). The questions that guided the investigation were related primarily to determination of their origin and the context of their use, as well as the possibility of recycling and reclamation after they were discarded. We perform techno-morphological, raw materials and use-wear analyses. The results indicate that, given their form, the raw materials, an important amount of edge scarring and evidence of contact with metal, all of the pieces were used as gunflints and are of European origin. [ABSTRACT FROM AUTHOR]

Research for evaluation of geologic hazards involving earthquakes and volcanic eruptions in southern Argentina seems to have historically received little attention. Nevertheless, the relatively small work done indicates a Neogene tectonic architecture in the area with capability of generating potential hazardous earthquakes in a growing population region. Seismicity and some morphotectonic evidences of Quaternary activity of the Magallanes-Fagnano left-lateral fault system in the transform boundary between South America and Scotia plates, are analysed in this paper. This fault system is considered to be an important seismogenic source, responsible for large earthquakes that have occurred in southern Argentina. Some examples from the South and Austral Andean Volcanic Zones are also examined in order to show recent volcanic activity which also generated crustal seismicity. Preliminary hazard estimation clearly shows the presence of both potentially active volcanic centres in southern Patagonia that may also trigger seismicity and the high probability for large crustal earthquake generation. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Successful North Americans, Douglas and Kristine Tompkins, have used their personal wealth and business know-how to become among the most powerful expatriate land owners in Chile and Argentina. In Chilean Patagonia's Aysén region, Kristine Tompkins' conservation foundation purchased the historical Chacabuco Valley Station, seeking to reverse the impacts of pastoralism and create a national park. Whilst in the United States and Europe the Tompkins' efforts have been applauded, many residents of the Chacabuco Valley area are concerned by the idea of outsiders holding decision making power on land use. The situation in Aysén speaks to a complex of broader anthropological debate regarding the neoliberalisation of conservation and, in particular, the role of ecophilanthropy in promoting capitalism. By examining the ways in which the Chacabuco Valley is undergoing transformation, this paper explores the relationship between ecophilanthropy, capitalism, and conservation. Of particular interest is how images are produced and then transformed into commodities as the strategies of business are incorporated into conservation policy and practice. [ABSTRACT FROM AUTHOR]

This paper describes the diversity, taphonomy and palaeoecology of angiosperm leaves that dominate a palaeoflora of Cretaceous (Cenomanian–Coniacian) age from the Mata Amarilla Formation in the Austral Basin, south-west Patagonia, Argentina. Twelve morphotypes of angiosperm leaves are recognized based on foliar morphotype analysis of more than 500 specimens. These were divided into six morphological groups based on major architectural patterns. The relative dominance of these morphotypes, mode of preservation and relationship with sedimentary facies were evaluated from two levels within the formation. This analysis identified two different plant palaeocommunities. The lower, María Elena, level (MEL) was deposited in a marine coastal area on a subaerial delta plain; the dominant angiosperm morphotypes preserved in it are group 1 (MA100) and group 2 (MA101, 102); morphotypes MA109 and 110 are scarce but exclusive to this level. The upper, Mata Amarilla, level (MAL), accumulated inland in flood-plain environments; the most abundant angiosperm morphotypes are groups 3 (MA103–105), 4 (MA106) and 1 (MA100); morphotypes MA103–105 and 108 are exclusive to this level. Comparisons with other floras of similar age from Antarctica, Australia and New Zealand indicate that the Mata Amarilla flora has a slightly higher morphological diversity of angiosperm leaves, providing the first evidence for an angiosperm-dominated early Late Cretaceous macroflora in south-west Gondwana. [ABSTRACT FROM AUTHOR]

Abstract The purpose of this paper was to synthesize observations of 21 cold temperate lakes from Patagonia, Argentina. To do this, objective limnological variables and the phytoplankton summer structure were analysed using multivariate statistical tools. The results suggest that the most important variables defined a trophic gradient based on nutrients, conductivity and phytoplanktonic attributes. Cluster analysis pointed to three groups of lakes. Steppe lakes (group III) were distinguished from mountain-Andean lakes (groups I and II) through their higher conductivity and ammonia concentration values, higher net phytoplankton density and lower species diversity. The two groups of Andean lakes differed with regard to the biomass of Bacillariophyceae and Prymnesiophyceae, water temperature and dissolved inorganic nitrogen concentration. The influence of the biomass (as biovolume) of each taxonomic group in lakes of different trophic status was examined. Although all Andean lakes appear to be similar, as shown by their similar salt and nutrient concentration values, the phytoplankton biomass split into different taxa and clearly distinguished subgroups. The work presents original information about the phytoplanktonic community structure from all the lakes and the first limnological data on 10 of them, from a region that is poorly known. [ABSTRACT FROM AUTHOR]