Search

Background: The Gran Chaco ecoregion is a well-known hotspot of several neglected tropical diseases (NTDs) including Chagas disease, soil-transmitted helminthiasis and multiparasitic infections. Interspecific interactions between parasite species can modify host susceptibility, pathogenesis and transmissibility through immunomodulation. Our objective was to test the association between human co-infection with intestinal parasites and host parasitaemia, infectiousness to the vector and immunological profiles in Trypanosoma cruzi-seropositive individuals residing in an endemic region of the Argentine Chaco. Methods: We conducted a cross-sectional serological survey for T. cruzi infection along with an intestinal parasite survey in two adjacent rural villages. Each participant was tested for T. cruzi and Strongyloides stercoralis infection by serodiagnosis, and by coprological tests for intestinal parasite detection. Trypanosoma cruzi bloodstream parasite load was determined by quantitative PCR (qPCR), host infectiousness by artificial xenodiagnosis and serum human cytokine levels by flow cytometry. Results: The seroprevalence for T. cruzi was 16.1% and for S. stercoralis 11.5% (n = 87). We found 25.3% of patients with Enterobius vermicularis. The most frequent protozoan parasites were Blastocystis spp. (39.1%), Giardia lamblia (6.9%) and Cryptosporidium spp. (3.4%). Multiparasitism occurred in 36.8% of the examined patients. Co-infection ranged from 6.9% to 8.1% for T. cruzi-seropositive humans simultaneously infected with at least one protozoan or helminth species, respectively. The relative odds of being positive by qPCR or xenodiagnosis (i.e. infectious) of 28 T. cruzi-seropositive patients was eight times higher in people co-infected with at least one helminth species than in patients with no such co-infection. Trypanosoma cruzi parasite load and host infectiousness were positively associated with helminth co-infection in a multiple regression analysis. Interferon-gamma (IFN-γ) response, measured in relation to interleukin (IL)-4 among humans infected with T. cruzi only, was 1.5-fold higher than for T. cruzi-seropositive patients co-infected with helminths. The median concentration of IL-4 was significantly higher in T. cruzi-seropositive patients with a positive qPCR test than in qPCR-negative patients. Conclusions: Our results show a high level of multiparasitism and suggest that co-infection with intestinal helminths increased T. cruzi parasitaemia and upregulated the Th2-type response in the study patients. [ABSTRACT FROM AUTHOR]

With its proclamation of universal suffrage in 1952, Bolivia fits into Samuel Huntington's "second short wave of democratization" (1943–1963). In 1952, all women and men gained the right to vote, marking a significant step towards democratization by including previously excluded groups. Literate women had already obtained municipal voting rights in 1945 under a populist government aiming for broader political participation. However, women first voted in 1947, after the oligarchy overthrew this government in 1946 and sought to regain power by repressing the opposition parties and previously marginalized sectors. Unexpectedly, it supported women's suffrage for national elections by the late 1940s. What prompted various political parties to support women's suffrage in the late 1940s? This paper explores how women in Bolivia gained the right to vote and what role the feminist movement and power struggles played in obtaining women's suffrage. Beginning in the 1920s with a study of the emergence of the feminist movement and its evolution during the decades of the 1930s (the Chaco War) and 1940s, the paper culminates with an assessment of feminism's impact on public opinion as well as the importance of the growing politicization of women in the 1940s. [ABSTRACT FROM AUTHOR]

Communicating climate change projections to diverse stakeholders and addressing their concerns is crucial for fostering effective climate adaptation. This paper explores the use of storyline projections as an intermediate technology that bridges the gap between climate science and local knowledge in the Pilcomayo basin. Through fieldwork and interviews with different stakeholders, key environmental concerns influenced by climate change were identified. Traditional approaches to produce regional climate information based on projections often lack relevance to local communities and fail to address their concerns explicitly. By means of storylines approach to evaluate climate projections and by differentiating between upper and middle-lower basin regions and focusing on dry (winter) and rainy (summer) seasons, three qualitatively different storylines of plausible precipitation and temperature changes were identified and related to the main potential risks. By integrating these climate results with local knowledge, a summary of the social and environmental impacts related to each storyline was produced, resulting in three narrated plausible scenarios for future environmental change. The analysis revealed that climate change significantly influences existing issues and activities in the region. Projected trends indicate a shift towards warmer and drier conditions, with uncertainties mainly surrounding summer rainfall, which impacts the probability of increased flooding and river course changes, two of the most concerning issues in the region. These findings serve as a foundation for problem-specific investigations and contribute to informed decision-making for regional climate adaptation. Finally, we highlight the importance of considering local concerns when developing climate change projections and adaptation strategies. [ABSTRACT FROM AUTHOR]

Prof. Norma Klahn (Literature, UCSC) and Prof. Guillermo Delgado-P., transcribed, annotated, and edited an interview with the late Bolivian fiction writer, poet and journalist, Jesús Urzagasti (1941-2013), when he visited the CLRC and the Latin American Studies program at UCSC in April of 2003.

Andean anthropologist reviews Mario Blaser's Storytelling Globlization from the Chaco and Beyond. (2010)

Abstract Background The Gran Chaco ecoregion is a well-known hotspot of several neglected tropical diseases (NTDs) including Chagas disease, soil-transmitted helminthiasis and multiparasitic infections. Interspecific interactions between parasite species can modify host susceptibility, pathogenesis and transmissibility through immunomodulation. Our objective was to test the association between human co-infection with intestinal parasites and host parasitaemia, infectiousness to the vector and immunological profiles in Trypanosoma cruzi-seropositive individuals residing in an endemic region of the Argentine Chaco. Methods We conducted a cross-sectional serological survey for T. cruzi infection along with an intestinal parasite survey in two adjacent rural villages. Each participant was tested for T. cruzi and Strongyloides stercoralis infection by serodiagnosis, and by coprological tests for intestinal parasite detection. Trypanosoma cruzi bloodstream parasite load was determined by quantitative PCR (qPCR), host infectiousness by artificial xenodiagnosis and serum human cytokine levels by flow cytometry. Results The seroprevalence for T. cruzi was 16.1% and for S. stercoralis 11.5% (n = 87). We found 25.3% of patients with Enterobius vermicularis. The most frequent protozoan parasites were Blastocystis spp. (39.1%), Giardia lamblia (6.9%) and Cryptosporidium spp. (3.4%). Multiparasitism occurred in 36.8% of the examined patients. Co-infection ranged from 6.9% to 8.1% for T. cruzi-seropositive humans simultaneously infected with at least one protozoan or helminth species, respectively. The relative odds of being positive by qPCR or xenodiagnosis (i.e. infectious) of 28 T. cruzi-seropositive patients was eight times higher in people co-infected with at least one helminth species than in patients with no such co-infection. Trypanosoma cruzi parasite load and host infectiousness were positively associated with helminth co-infection in a multiple regression analysis. Interferon-gamma (IFN-γ) response, measured in relation to interleukin (IL)-4 among humans infected with T. cruzi only, was 1.5-fold higher than for T. cruzi-seropositive patients co-infected with helminths. The median concentration of IL-4 was significantly higher in T. cruzi-seropositive patients with a positive qPCR test than in qPCR-negative patients. Conclusions Our results show a high level of multiparasitism and suggest that co-infection with intestinal helminths increased T. cruzi parasitaemia and upregulated the Th2-type response in the study patients. Graphical Abstract

Abstract Background The emergence of pyrethroid resistance has threatened the elimination of Triatoma infestans from the Gran Chaco ecoregion. We investigated the status and spatial distribution of house infestation with T. infestans and its main determinants in Castelli, a municipality of the Argentine Chaco with record levels of triatomine pyrethroid resistance, persistent infestation over 2005–2014, and limited or no control actions over 2015–2020. Methods We conducted a 2-year longitudinal survey to assess triatomine infestation by timed manual searches in a well-defined rural section of Castelli including 14 villages and 234 inhabited houses in 2018 (baseline) and 2020, collected housing and sociodemographic data by on-site inspection and a tailored questionnaire, and synthetized these data into three indices generated by multiple correspondence analysis. Results The overall prevalence of house infestation in 2018 (33.8%) and 2020 (31.6%) virtually matched the historical estimates for the period 2005–2014 (33.7%) under recurrent pyrethroid sprays. While mean peridomestic infestation remained the same (26.4–26.7%) between 2018 and 2020, domestic infestation slightly decreased from 12.2 to 8.3%. Key triatomine habitats were storerooms, domiciles, kitchens, and structures occupied by chickens. Local spatial analysis showed significant aggregation of infestation and bug abundance in five villages, four of which had very high pyrethroid resistance approximately over 2010–2013, suggesting persistent infestations over space-time. House bug abundance within the hotspots consistently exceeded the estimates recorded in other villages. Multiple regression analysis revealed that the presence and relative abundance of T. infestans in domiciles were strongly and negatively associated with indices for household preventive practices (pesticide use) and housing quality. Questionnaire-derived information showed extensive use of pyrethroids associated with livestock raising and concomitant spillover treatment of dogs and (peri) domestic premises. Conclusions Triatoma infestans populations in an area with high pyrethroid resistance showed slow recovery and propagation rates despite limited or marginal control actions over a 5-year period. Consistent with these patterns, independent experiments confirmed the lower fitness of pyrethroid-resistant triatomines in Castelli compared with susceptible conspecifics. Targeting hotspots and pyrethroid-resistant foci with appropriate house modification measures and judicious application of alternative insecticides with adequate toxicity profiles are needed to suppress resistant triatomine populations and prevent their eventual regional spread. Graphical Abstract

The South American Dry Diagonal, also called the Diagonal of Open Formations, is a large region of seasonally dry vegetation extending from northeastern Brazil to northern Argentina, comprising the Caatinga, Cerrado, and Chaco subregions. A growing body of phylogeography literature has determined that a complex history of climatic changes coupled with more ancient geological events has produced a diverse and endemic‐rich Dry Diagonal biota. However, the exact drivers are still under investigation, and their relative strengths and effects are controversial. Pleistocene climatic fluctuations structured lineages via vegetation shifts, refugium formation, and corridors between the Amazon and Atlantic forests. In some taxa, older geological events, such as the reconfiguration of the São Francisco River, uplift of the Central Brazilian Plateau, or the Miocene inundation of the Chaco by marine incursions, were more important. Here, we review the Dry Diagonal phylogeography literature, discussing each hypothesized driver of diversification and assessing degree of support. Few studies statistically test these hypotheses, with most support drawn from associating encountered phylogeographic patterns such as population structure with the timing of ancient geoclimatic events. Across statistical studies, most hypotheses are well supported, with the exception of the Pleistocene Arc Hypothesis. However, taxonomic and regional biases persist, such as a proportional overabundance of herpetofauna studies, and the under‐representation of Chaco studies. Overall, both Pleistocene climate change and Neogene geological events shaped the evolution of the Dry Diagonal biota, though the precise effects are regionally and taxonomically varied. We encourage further use of model‐based analyses to test evolutionary scenarios, as well as interdisciplinary collaborations to progress the field beyond its current focus on the traditional set of geoclimatic hypotheses. [ABSTRACT FROM AUTHOR]

Indigenous Peoples are gaining renewed attention within both policy and academia, as examples of “resilience” and of non‐humanist, non‐modern ways of relating to nature, which might, it is hoped, provide tools to withstand the socio‐ecological crises associated with “the Anthropocene”. This paper argues that such representations obscure both their own colonial foundations and the ongoing forms of racialised dispossession and ecocide faced by Indigenous Peoples today. Instead, we conceptualise indigeneity and nature as deeply entangled categories that are co‐produced with capitalist modernity. Engaging anti‐colonial and Marxist scholarship, and drawing on our long‐term research with Indigenous movements in Bolivia and Colombia, we highlight how discursive and material assemblages of indigeneity and nature are dialectically linked to capitalist processes of dispossession and subaltern efforts to contest these. We further highlight how romanticised accounts of non‐modern nature‐cultures are unsettled by the violent world‐making of colonial capitalism and the unequal burdens placed on Indigenous territories and bodies. We use an ethnographic vignette from the Bolivian Chaco to illustrate the messy everyday ways in which real Indigenous people navigate, contest, endure, and make do amidst the contradictory processes of racialisation, dispossession, and conditional recognition that characterise their positioning within colonial capitalism. In doing so, we show how thinking from the sacrifice zones of extractive capitalism unsettles contemporary debates on decolonising nature in the Anthropocene. [ABSTRACT FROM AUTHOR]

Background: The emergence of pyrethroid resistance has threatened the elimination of Triatoma infestans from the Gran Chaco ecoregion. We investigated the status and spatial distribution of house infestation with T. infestans and its main determinants in Castelli, a municipality of the Argentine Chaco with record levels of triatomine pyrethroid resistance, persistent infestation over 2005–2014, and limited or no control actions over 2015–2020. Methods: We conducted a 2-year longitudinal survey to assess triatomine infestation by timed manual searches in a well-defined rural section of Castelli including 14 villages and 234 inhabited houses in 2018 (baseline) and 2020, collected housing and sociodemographic data by on-site inspection and a tailored questionnaire, and synthetized these data into three indices generated by multiple correspondence analysis. Results: The overall prevalence of house infestation in 2018 (33.8%) and 2020 (31.6%) virtually matched the historical estimates for the period 2005–2014 (33.7%) under recurrent pyrethroid sprays. While mean peridomestic infestation remained the same (26.4–26.7%) between 2018 and 2020, domestic infestation slightly decreased from 12.2 to 8.3%. Key triatomine habitats were storerooms, domiciles, kitchens, and structures occupied by chickens. Local spatial analysis showed significant aggregation of infestation and bug abundance in five villages, four of which had very high pyrethroid resistance approximately over 2010–2013, suggesting persistent infestations over space-time. House bug abundance within the hotspots consistently exceeded the estimates recorded in other villages. Multiple regression analysis revealed that the presence and relative abundance of T. infestans in domiciles were strongly and negatively associated with indices for household preventive practices (pesticide use) and housing quality. Questionnaire-derived information showed extensive use of pyrethroids associated with livestock raising and concomitant spillover treatment of dogs and (peri) domestic premises. Conclusions: Triatoma infestans populations in an area with high pyrethroid resistance showed slow recovery and propagation rates despite limited or marginal control actions over a 5-year period. Consistent with these patterns, independent experiments confirmed the lower fitness of pyrethroid-resistant triatomines in Castelli compared with susceptible conspecifics. Targeting hotspots and pyrethroid-resistant foci with appropriate house modification measures and judicious application of alternative insecticides with adequate toxicity profiles are needed to suppress resistant triatomine populations and prevent their eventual regional spread. [ABSTRACT FROM AUTHOR]

Between March and June of 1759, a general military campaign ("entrada general") towards Chaco was held by the Governance of Tucumán, Buenos Aires and Paraguay. Despite the high amount of documents that were produced at the moment -both written papers and maps- this event has aroused little interest in historiography. In this paper, we aim at reviewing this military campaign from a historico-anthropological approach that resituates the documents in their contexts of production, by considering the complex relationships that link empirical facts -the actions-, imaginaries -the representations- and what is registered in the documents -the discourses. In this way, we present an ethnographic interpretation of the military campaign that delves into the facts, the different actors' objectives and motivations, and the distinct interethnic scenarios that were developed on the borders of Chaco. [ABSTRACT FROM AUTHOR]

The Paraguayan Chaco is increasingly known for the extreme rates of forest loss caused by the rapid expansion of cattle ranching and crop farming over the last few decades. Knowledge of its twentieth-century land-use history, however, remains limited. In this article, I address that gap by discussing land-use dynamics since the 1900s in the Pilcomayo River basin, a part of the Chaco that borders Argentina and Bolivia, and hosts a great diversity of actors and land uses. Using the concept of land-use regimes, I show that the area, once characterized by what can be called an Indigenous mixed-use regime, transitioned to a land-use regime dominated by livestock herding by Argentine Criollo settlers after the Chaco War (1932–35), and then again to one of large cattle ranches managed by absentee owners toward the end of the twentieth century. No land-use regime ever completely dominated the area, however, and I use this fact as a starting point to then discuss how using the concept of land regimes can help direct attention to the coexistence of regimes in space and to their relationships in a way that helps refine our understanding of land-use transitions. [ABSTRACT FROM AUTHOR]

Geoclimatic events driving South American aridization have generated biota differentiation due to barriers and new environment formation. New environments allow species climatic niche evolution, or the geographical expansion of an existing one. Understanding the role these processes play may clarify the evolution of South American biota. Gomphrena L. ranges across almost all the continent's arid environments. We tested whether South American drylands are biogeographically connected through the Gran Chaco but, due to different aridity levels, lineage diversification could have also been associated with the evolution of climatic niches and morphological or physiological traits. With available data, we generated a dated phylogeny, estimated ancestral ranges, performed diversification analyses, reconstructed ancestral states of two characters, and examined if niches have changed between lineages. Results showed that Gomphrena diversified throughout the easternmost South American drylands ~15.4 Ma, and subsequently three independent clades colonized the western arid regions during the last Andean pulse, and after the marine transgressions (~4.8–0.4 Ma) via the Gran Chaco. The colonization implied an increase in the diversification rate of annuals over perennials and the progressive east–west differentiation of the occupied climatic niche. This diversification was influenced by C4 photosynthesis, which could have acted as a niche opener to conquer new environments after the Paranaean Sea withdrew. Spatiotemporal patterns found in Gomphrena suggest that geographical expansion and evolution of climatic niches played a common but decoupled role in promoting diversification. These results show that the Gran Chaco may have acted as a historical connection linking South American drylands. [ABSTRACT FROM AUTHOR]

The diet and neo-taphonomy of Glaucidium nana (Aves, Strigiformes), evaluated from pellets and leftover prey recovered in nest-boxes from a National Park of southeastern Patagonia are studied. Comparative evaluations are conducted with microvertebrate samples obtained from other raptors, particularly those of G. brasilianum from the Chaco forest in Argentina. The diet of G. nana reported here agrees with the generalist trophic behaviour of this species already documented, which feeds on invertebrate (insects and arachnids) and vertebrate prey (amphibian, reptiles, birds and mammals), mainly caviomorph rodents heavier than itself. The taphonomic attributes allow us to place the two species of Glaucidium in the moderate modification category. They could deposit their diet remains in several open-air sites, mainly in wooded and rocky areas, where the cavity nests are located. Later, their bone accumulation –composed of microvertebrates with evidence of moderate bone modifications and/or with articulated skulls and limb bones without digestive corrosion- might integrate into the lithosphere. Understanding the trophic interactions between predators and prey, and their taphonomic signatures, as well as identifying their nesting areas, is crucial for archaeology/palaeontology analysis and for developing effective conservation and management strategies within protected areas. [ABSTRACT FROM AUTHOR]

Chaco is the largest remaining continuous tropical dry forest on the American continent and has one of the highest deforestation rates in the world. Copernicia alba Morong ex Morong & Britton is a typical species of Chaco forests and has been subjected to predatory extraction in its areas of occurrence. This study aims to assess the diversity and genetic structure of C. alba populations in the Brazilian Chaco region. By employing single-nucleotide polymorphism (SNP) markers, this research seeks to generate insights to guide effective management and conservation strategies for this palm tree. To obtain the SNPs, genomic libraries were developed using the genotyping-by-sequencing (GBS) approach. Populations showed considerable levels of genetic diversity (HE). The inbreeding coefficient (f) was negative for all populations, indicating an excess of heterozygotes. Additionally, clear signs of genetic flow were observed, indicating low to moderate genetic differentiation between populations. We detected 65 outlier SNPs associated mainly with general metabolic processes. Despite these results, conservation efforts should be adopted to avoid the loss of genetic variation. Conservation in situ or ex situ is pointed out as an important strategy for the preservation of C. alba populations, prioritizing sampling throughout the distribution area. The information obtained in this study will contribute to the conservation of genetic diversity, increasing the chances of the natural populations of C. alba persisting over time. [ABSTRACT FROM AUTHOR]

The objective of this study is to characterize the taphonomic signature of Strix chacoensis in bone and tooth remains of microvertebrates (birds and micromammals). The chaco owl is a bird of prey whose diet and bone modification patterns are little known. In a sample of 41 pellets, an unusual proportion of bird remains over mammal remains was observed. We evaluate the ecological implications of this phenomenon, which could designate Strix chacoensis as a bioindicator of well-preserved forest and shrubland environments when combined with the specific ecological requirements of the prey species. Furthermore, taphonomic patterns vary across taxonomic groups: bird remains exhibited lower modifications due to breakage and digestion compared to micromammal remains. Therefore, this raptor can be characterized as having a minimal impact on bird remains and an intermediate impact on mammal remains. [ABSTRACT FROM AUTHOR]

In this paper we study the relationships between plants and extinct megafauna by examining the characteristics of the vegetation in the central region of Argentina (i.e. Espinal, Monte, and Chaco phytogeographic regions). First, we study the size, shape, quantity, and characteristics of fruits and seeds. We also evaluate the presence of mechanical (spinescence and wood density) and chemical (secondary metabolic compounds) defenses against high rates of herbivory. Complementarily, we assess the importance these plants had for human populations, using archeological, ethnographic, and current data. A high percentage of the analyzed plants met the criteria proposed for fruits and seeds dispersed by megafauna, together with a high frequency of spinescence, high density woods, and secondary metabolites. We propose that these traits cannot be explained by the herbivory pressure of extant fauna in the area, but rather developed in interaction with currently extinct fauna. We suggest that Pleistocene megafaunal extinction had important consequences in the region due to their role as ecosystem engineers and to vegetation's characteristics, which were probably strongly shaped by megafauna activities. Among these consequences, we discuss the loss of certain interactions between these animals and vegetation, such as loss of seed dispersal mechanisms, shrub invasion, and increased susceptibility of vegetation to fire. Other effects for hunter-gatherer groups were the generation of highly regulated mobility patterns and the formation of barriers for the dispersal of prey. Finally, we also discuss the importance of these plants for human populations as food, construction material, medicines and firewood. Likewise, the role of humans as "heirs" of the megafauna in the propagation of tree and shrub species is highlighted. [ABSTRACT FROM AUTHOR]

Research by Cynthia Irwin-Williams and the San Juan Valley Archaeological Project during the 1970s included investigations at Salmon Pueblo, near modern Bloomfield, NM. Interest focused on the construction and early occupation by immigrants from Chaco Canyon. Research also included the 80 km Great North Road, which joined Pueblo Alto at the southern end with Salmon Pueblo at the northern terminus. In order to investigate the North Road, Pierre Morenon conducted an intensive foot survey of the road trajectory and associated features. A large ceramic collection from the road and nearby sites was analyzed by Hayward Franklin. Pottery types dated mostly from 1050 to 1130 CE. A typical assemblage of decorated and utility pottery came northward from Chaco Canyon centers. Smaller amounts of northern San Juan pottery also occurred, signifying transport of ceramics and other goods southward from outliers at Salmon and Aztec Pueblos. [ABSTRACT FROM AUTHOR]

This study examines the archaeological record for water management in Chaco Canyon, New Mexico, in relation to the Bonito Paleochannel cycle, ca. AD 1075–1150. We present evidence for a canal system at Pueblo Bonito that was destroyed by the entrenchment of the paleochannel. This canal system is associated with the peak of great house construction. Other water control features throughout the canyon were small and date to the period of paleochannel aggradation or afterward. We suggest that while the Pueblo Bonito canals represent some degree of corporate group investment, small features were managed at the household level. The limited archaeological evidence for formal water control infrastructure can be explained at least in part by the physical geography of Chaco Canyon, which we view as essentially a regional-scale water harvesting structure. [ABSTRACT FROM AUTHOR]

The subnational implementation of forest protection legislation is an important aspect of forest governance. In this article, I explore how competing interests regarding production and conservation affect forest protection at the local level in the Argentine Chaco Forest, which represents 60 percent of the Chaco Americano, the second largest forest in South America. Employing original and administrative data, I assess whether deforestation is associated with large producers, who seek to expand soy cultivation into forestlands, and the presence of indigenous communities, who favor forest protection. Quantitative analysis of the departments in the Chaco region suggests that overall deforestation is associated with soy cultivation and past deforestation. In contrast, forest loss in protected areas, which should be zero but represents almost half of total deforestation during the studied period, is positively associated with the number of indigenous communities in the department, the share of protected forestlands, the power of large producers, and past deforestation. Qualitative analysis suggests that lands inhabited by indigenous communities were generally granted protected status, as requested by national legislation and consistent with demands of indigenous groups and their allies. Yet, this protected status has been watered down by permissive regulations and the overall lax enforcement of forest protection legislation, which were in turn driven by large producers invested in cropland expansion. [ABSTRACT FROM AUTHOR]

Background: Chagas disease, caused by Trypanosoma cruzi, is still a public health problem in Latin America and in the Southern Cone countries, where Triatoma infestans is the main vector. We evaluated the relationships among the density of green vegetation around rural houses, sociodemographic characteristics, and domestic (re)infestation with T. infestans while accounting for their spatial dependence in the municipality of Pampa del Indio between 2007 and 2016. Methods: The study comprised sociodemographic and ecological variables from 734 rural houses with no missing data. Green vegetation density surrounding houses was estimated by the normalized difference vegetation index (NDVI). We used a hierarchical Bayesian logistic regression composed of fixed effects and spatial random effects to estimate domestic infestation risk and quantile regressions to evaluate the association between surrounding NDVI and selected sociodemographic variables. Results: Qom ethnicity and the number of poultry were negatively associated with surrounding NDVI, whereas overcrowding was positively associated with surrounding NDVI. Hierarchical Bayesian models identified that domestic infestation was positively associated with surrounding NDVI, suitable walls for triatomines, and overcrowding over both intervention periods. Preintervention domestic infestation also was positively associated with Qom ethnicity. Models with spatial random effects performed better than models without spatial effects. The former identified geographic areas with a domestic infestation risk not accounted for by fixed-effect variables. Conclusions: Domestic infestation with T. infestans was associated with the density of green vegetation surrounding rural houses and social vulnerability over a decade of sustained vector control interventions. High density of green vegetation surrounding rural houses was associated with households with more vulnerable social conditions. Evaluation of domestic infestation risk should simultaneously consider social, landscape and spatial effects to control for their mutual dependency. Hierarchical Bayesian models provided a proficient methodology to identify areas for targeted triatomine and disease surveillance and control. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The magnitude of life on Earth and human limitations hinder the understanding of even the most basic aspects of biodiversity, such as the identity of species inhabiting the Earth, the so‐called Linnean shortfall. Evaluating patterns in species description dates and their relationship with macroecological variables can help guide where taxonomic efforts should be focused. Therefore, we aim to assess the Linnean shortfall in the knowledge of New World coralsnake biodiversity. We modelled species description dates and estimated that approximately one‐third of the coralsnake diversity remains unknown. The undescribed species are evolutionarily closely related to the already described species. Moreover, recently described species in the group have more restricted geographic ranges and tend to be small‐bodied. The western Amazon and the dry diagonal (i.e. Caatinga, Cerrado, and Chaco) are the areas with the oldest description dates. However, assemblages in these areas have the largest average geographic distances to the type locality of their species, suggesting that little taxonomic effort has been dedicated intrinsically to these regions. We suggest that allocating taxonomic efforts to the dry diagonal and the use of integrative taxonomic techniques for better species delimitation are imperative to fill the Linnean shortfall for the New World coralsnakes. [ABSTRACT FROM AUTHOR]

This paper analyzes vowel shifts in Wichi (Mataguayan, South America) between the 18th and early 20th centuries, some of which contributed to the emergence of the Pilcomayeño and Bermejeño dialects. Based on a historical database and using the comparative method, we date the vowel shift over the period we have named as Middle Wichi. At the early stage of this period, the /e/ > /a/ lowering is analyzed as a sporadic change, spread across the dialects in part of the vocabulary. At a later stage, the chain shift /ɑ/ > /o/ > /u/ > /e, i/, the merger of /u/ with /e/ and /i/, and the sporadic change of /i/>/e/ lowering in some words took place in Bermejeño. The paper explores implications in the implementation of sound change, the regular changes and the lexical diffusion, in particular, in chain shifting. It also explores some connections with other Mataguayan languages in both the lowering e>a and the possible causes of the changes. Thus, the paper contributes to the historical study of the Wichi language and the Mataguayan family in the Gran Chaco area in South America. [ABSTRACT FROM AUTHOR]

In just a few years motorcycles had become an irreplaceable object for the daily life of Indigenous people in the Gran Chaco region. In spite of their pervasiveness, there are still many aspects to this current dissemination that remain to be unraveled. This paper explores the ways in which motorcycles have been incorporated into Indigenous material culture and the ways they are reshaping Indigenous perceptions and relations with the local environment. Starting from the machines and their uses is a way to not confine Indigenous people to a position as victims of modernity, but rather to recognize their proactive role in the ongoing reproduction and transformation of their cultural world. For this purpose, I take the example of the Wichí fishery to see how this cultural practice is changing as fishermen adopt motorcycles as means of transport. I investigate this practice and its transformations based on ethnographic fieldworks carried out with several communities settled on the banks of the Pilcomayo River, as well as readings of the ethnological literature which contains detailed descriptions of this practice. By tracing its past and ongoing transformations, I show how the hold and spatial organization of Wichí fishery has evolved as motorcycles spread to the whole Pilcomayo area. Their adoption redefines fishermen perceptions and relations with the surrounding environment, which is now understood from a new mechanized and motorized perspective of capitalization and exploitation. Indeed, while motorcycles allow them to integrate into the market, they further promote market penetration on Indigenous lands. At the same time, I demonstrate how motorcycles allow fishermen to overcome the inconveniences of an intractable river and new infrastructures that hinder fishing practices, as well as to bypass the attempts to privatize the riverbanks. In a way, the fishermen are more resilient to these sudden changes thanks to motorcycles. [ABSTRACT FROM AUTHOR]

Copyright of Mundo Agrario is the property of Universidad Nacional de La Plata and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Triatoma garciabesi, a potential vector of the parasitic protozoan Trypanosoma cruzi, which is the causative agent of Chagas disease, is common in peridomestic and wild environments and found throughout northwestern and central Argentina, western Paraguay and the Bolivian Chaco. Genetic differentiation of a species across its range can help to understand dispersal patterns and connectivity between habitats. Dispersal by flight is considered to be the main active dispersal strategy used by triatomines. In particular, the morphological structure of the hemelytra is associated with their function. The aim of this study was to understand how genetic diversity is structured, how morphological variation of dispersal-related traits varies with genetic diversity and how the morphological characteristics of dispersal-related traits may explain the current distribution of genetic lineages in this species. Methods: Males from 24 populations of T. garciabesi across its distribution range were examined. The cytochrome c oxidase I gene (coI) was used for genetic diversity analyses. A geometric morphometric method based on landmarks was used for morpho-functional analysis of the hemelytra. Centroid size (CS) and shape of the forewing, and contour of both parts of the forewing, the head and the pronotum were characterised. Length and area of the forewing were measured to estimate the aspect ratio. Results: The morphometric and phylogenetic analysis identified two distinct lineages, namely the Eastern and Western lineages, which coincide with different ecological regions. The Eastern lineage is found exclusively in the eastern region of Argentina (Chaco and Formosa provinces), whereas the Western lineage is prevalent in the rest of the geographical range of the species. CS, shape and aspect ratio of the hemelytra differed between lineages. The stiff portion of the forewing was more developed in the Eastern lineage. The shape of both portions of the hemelytra were significantly different between lineages, and the shape of the head and pronotum differed between lineages. Conclusions: The results provide preliminary insights into the evolution and diversification of T. garciabesi. Variation in the forewing, pronotum and head is congruent with genetic divergence. Consistent with genetic divergence, morphometry variation was clustered according to lineages, with congruent variation in the size and shape of the forewing, pronotum and head. [ABSTRACT FROM AUTHOR]

During the late eleventh century AD, a episode of erosion in Chaco Canyon, New Mexico, threatened to destroy portions of the Pueblo Bonito great house and possibly other large buildings. Known as the Bonito Paleochannel, this large arroyo meant the loss of significant amounts of surface water from valley-wide flooding originating in upstream and tributary sources. We believe that erosion was probably the result of an increasing size and frequency of floods. There is no compelling evidence that agriculture was affected by the paleochannel but we hypothesize that great house construction became extremely difficult. Consequently, the impact of the Bonito Paleochannel cycle may have been felt most in the political economy. [ABSTRACT FROM AUTHOR]

Contemporary debates on posthumanism and the planetary environmental crisis have led to the questioning of the dichotomies and anthropocentrism of Western modernity. The Indigenous peoples of the Gran Chaco of Argentina, specifically the Qom or Toba, neither privileged the human above other beings that make up the world nor created nature/culture dichotomies. In other words they were, as other Amerindian peoples, neither humanists nor posthumanists. However, in recent decades, the Qom—who since 1960 have combined Pentecostal evangelicalism with shamanism and their particular animism—have begun to differentiate, at least discursively, religion from spirituality. If religion refers to the institutionalized evangelical universe, spirituality corresponds to what international Indigenist norms place within the "ancestral," which tends to be condemned as savage, demonic, dark, and, therefore, as something to be eradicated. The non-human beings of the natural world, the shamanic practices of healing, and the universe of vengeance and of witchcraft were always present—though questioned by official evangelicalism, now they gain greater visibility in religious spaces. This article analyzes aspects of Qom spirituality that challenge the dichotomies that the Indigenous themselves internalized and that destabilizes their perspectives. It considers how advocating a continuity that does not destroy plurality upholds the exceptionality of the human being to cause and solve a planetary crisis that, in regions such as the Gran Chaco, is directly associated with extractivism. Resumen: Los debates contemporáneos sobre el posthumanismo y la crisis medioambiental planetaria han llevado a cuestionar las dicotomías y el antropocentrismo de la modernidad occidental. Los pueblos indígenas del Gran Chaco de Argentina, concretamente los qom o toba, no privilegiaron lo humano por encima de los demás seres que conforman el mundo ni crearon dicotomías como naturaleza/cultura. En otras palabras, no son ni fueron, al igual que otros pueblos amerindios, humanistas ni posthumanistas. Sin embargo, en las últimas décadas, los qom–que desde 1960 combinan el evangelicalismo pentecostal con el chamanismo y su particular animismo- han empezado a diferenciar, al menos discursivamente, religión de espiritualidad. Si la religión se refiere al universo evangélico institucionalizado, la espiritualidad corresponde a lo que las normas indigenistas internacionales sitúan dentro de lo "ancestral", que tiende a ser condenado como salvaje, demoníaco, oscuro y, por tanto, como algo a erradicar. Los seres no-humanos del mundo natural, las prácticas chamánicas de curación y el universo de la venganza y de la brujería siempre estuvieron presentes -aunque cuestionados por el evangelismo oficial- ahora ganan mayor visibilidad en los rituales religiosos. En este artículo despliego aspectos de esta espiritualidad qom, que desafían las dicotomías que los propios indígenas internalizaron y que desestabilizan perspectivas, con el fin de considerar cómo abogar por una continuidad que no destruya la pluralidad, no sostenga la excepcionalidad del ser humano para causar y resolver una crisis planetaria que, en regiones como el Gran Chaco, están asociadas al extractivismo. [ABSTRACT FROM AUTHOR]

Archaeologists routinely create backdirt during excavation, but it is rarely acknowledged and remains surprisingly undertheorized. In this paper, we treat backdirt as a uniquely archaeological product that is socially constructed and guided by culturally and historically situated motivations. Using Chaco Canyon as a case study, we examine the ways in which project priorities changed over nearly 150 years of excavation and (more recently) re-excavation. We illustrate the importance of understanding backdirt as a social product by comparing the avifaunal assemblages created by two major excavation projects at the great house of Una Vida. Differences in these assemblages demonstrate how changes in research goals structured what was collected, what was left as backdirt, and how this ultimately impacts interpretations about Chaco history. Finally, we offer thoughts about the future role of backdirt in archaeological praxis as a space to welcome feminist and Indigenous perspectives in the construction of archaeological narratives. [ABSTRACT FROM AUTHOR]

In the Argentine Chaco — a world hotspot of agribusiness-driven deforestation — descendants of European settlers (gringos) who built manual cotton plantations on Indigenous land and labor in the twentieth century, have since been displaced from farming by the "soy boom." Nevertheless, plantation legacies persist in the racialized plant-relations of these actors today, and in their conflicted — and often acquiescent — attitudes to agribusiness. Drawing on emergent theories of the "Plantationocene," this essay examines how three settler interlocutors grieve the loss of plant-worlds that soy agribusiness has displaced, with a focus on living soil, cotton seeds, and potted roses. I show that these multispecies attachments perform a double role: while they sensitize these actors to the ecological fallouts of the soy boom, they also reinforce settler colonial plantation logics of racialized progress that ultimately feed their acquiescence to that agribusiness model. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ecological interactions of biota with natural ecosystems are still poorly understood. In Subtropical Dry forests, several stingless bees utilize cavities within trees for nesting. Due to their lack of morphological traits for creating these cavities, bees rely on other mechanisms to access and utilize hollow spaces. In the Argentinian Dry Chaco region, we set two main objectives: (1) Determine the richness of cavity-nesting bees and describe the characteristics of trees selected as substrates, and (2) identify the mechanisms employed by stingless bees in selecting trees with hollows. Observational records were used to identify bee-nesting sites, while standard vegetation inventory was conducted to assess preference. Structural equation models were employed to establish the selection mechanisms of tree species for nesting. We found 139 nests belonging to three species: Plebeia catamarcensis (n = 118), Plebeia molesta (n = 14), and Lestrimelitta (L.) chacoana (n = 2). Stingless bees, particularly smaller species like P. catamarcensis, specifically select Neltuma trees for nest installation. This preference is attributed to the presence of galleries and hollows within the heartwood, created by the larvae of Criodion angustatum beetle. Although the larval action may harm the mechanical structure of the trees and hasten their demise, it simultaneously creates suitable hollow spaces for the establishment of bee colonies. Further investigations into these species interactions within the forest are necessary to enhance management practices in this threatened ecosystem, recognizing the important ecological role of Neltuma genus as crucial for ensuring the availability of nesting substrates for these native stingless bees. [ABSTRACT FROM AUTHOR]

Background: The nationally determined contribution (NDC) presented by Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United Nations Framework Convention on Climate Change (UNFCCC) on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation (REDD+). In addition, climate change constitutes one of the greatest threats to forest biodiversity and ecosystem services. However, the soil organic carbon (SOC) stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under climate variability due to a lack of information. The objectives of this study were: (i) to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and (ii) to relate SOC stocks with spatial–temporal remotely sensed indices to determine biodiversity conservation concerns due to threats from high inter-annual climate variability. Methods: We used 1040 forest soil samples (0–30 cm) to generate spatially explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately 200 m. We selected 52 potential predictive environmental covariates, which represent key factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity threats from high inter-annual climate variability, we employed the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index (EVI) and land surface temperature (LST) images from Landsat imagery. Results: SOC model (0–30 cm depth) prediction accounted for 69% of the variation of this soil property across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C (2.71–2.84 Pg C with a probability of 90%) for a total area of 460,790 km2, where Chaco forests represented 58.4% of total SOC stored, followed by Andean Patagonian forests (16.7%) and Espinal forests (10.0%). SOC stock model was fitted as a function of regional climate, which greatly influenced forest ecosystems, including precipitation (annual mean precipitation and precipitation of warmest quarter) and temperature (day land surface temperature, seasonality, maximum temperature of warmest month, month of maximum temperature, night land surface temperature, and monthly minimum temperature). Biodiversity was influenced by the SOC levels and the forest regions. Conclusions: In the framework of the Kyoto Protocol and REDD+, information derived in the present work from the estimate of SOC in native forests can be incorporated into the annual National Inventory Report of Argentina to assist forest management proposals. It also gives insight into how native forests can be more resilient to reduce the impact of biodiversity loss. [ABSTRACT FROM AUTHOR]

We report the first records of Cuniculus paca for the Chaco or Western Region of Paraguay. The evidence consists of 18 records (63 photos and 12 videos) obtained through a camera trap located in a riparian forest of the Humid Chaco. The species showed solitary and nocturnal behavior and appeared near a stream that flows into the Paraguay River. [ABSTRACT FROM AUTHOR]

Pasturelands are characterized as grasslands utilized for cattle raising and consist of natural or exotic vegetation, predominantly grasses. In the context of sustainable production, the biodiversity of insects within grazing environments holds significant value. Dung beetles play a crucial role in sustaining pasturelands as the burial of feces by these beetles fosters ecological services indispensable for maintaining a robust and healthy environment. Given that different dung beetle species contribute to distinct environmental benefits, a comprehensive understanding of the species present in pasturelands, their origins, and the ecological services they provide is imperative. This study endeavors to compile comprehensive information on dung beetle species native to South America, emphasizing taxonomic precision and a confirmed affinity for cattle dung. Our findings are derived from a synthesis of literature and observational data, incorporating location information obtained from taxonomic revisions and specimen labels of specimens housed at CEMT. In South America, a total of 57 dung beetle species are documented that inhabit grazing areas and actively feed on cattle manure. These areas span diverse biomes encompassing native and/or introduced grasslands, which may include deforested sections within forest biomes such as Chaco, Pantanal, Cerrado, Caatinga, Pampa, Atlantic Forest, Amazon Forest, Paramo, Puna, Llanos, and Patagonia. The preponderance of species identified fall within the paracoprid category, recognized as particularly vital for the sustainability of pasturelands. Despite their acknowledged importance, a noticeable knowledge gap impedes the effective conservation of these species. This gap is a focal point of discussion in this study, addressing the challenges and opportunities for enhancing conservation efforts. The species documented in this research exhibit notable economic and environmental relevance in the context of sustainable livestock production, emphasizing the urgency and significance of initiatives that prioritize their conservation. [ABSTRACT FROM AUTHOR]

Argythamnia (Euphorbiaceae) comprises approximately 70 species and is widely distributed in the New World, mainly restricted to seasonal environments. It is represented by seven species in the biogeographic provinces of the Chaco and Pampa, which are characterized by vegetation mosaics of grasslands and forests. Some species are poorly known, with only 3–5 collections restricted to specific areas, whereas others have many records and a wide distribution throughout these two provinces. Morphological similarities among many species make identification difficult. After several expeditions to observe and collect samples in the field, bibliographic revision, and examination of herbarium specimens, we present a taxonomic treatment of Argythamnia in the Chaco and Pampa provinces, where we recognize five species and provide descriptions, an identification key, and a distribution map. In addition, we propose three synonyms, four neotypifications, four lectotypifications, and report the first records of A. salina in Brazil, and the first record of A. montevidensis in the Chaco from the state of Mato Grosso do Sul, Brazil, a species known to date in this country only from the Pampa of Rio Grande do Sul state. [ABSTRACT FROM AUTHOR]

Pyrethroid‐resistance is an emergent trait in populations of various insect species. For Triatoma infestans (Klug, 1834) (Heteroptera: Reduviidae), the major vector of Chagas disease in the southern part of South America, hotspot areas of pyrethroid‐resistance have recently been found in the Chaco Province of Argentina. Resistant condition can reduce fitness of individuals in the absence of insecticide exposure, that is, fitness costs. We evaluated the existence of developmental and/or reproductive costs in T. infestans collected from two areas of pyrethroid‐resistance in Chaco Province, Argentina. Three toxicological groups were defined from field‐collected insects: susceptible (survival <20%), moderately resistant (survival between 20% and 80%) and highly resistant (survival >80%). Cohorts of the three toxicological groups were followed‐up to study life cycle and reproductive parameters. Additionally, we parameterized matrix population growth models. First and IV nymphal stages of the resistant groups exhibited a longer stage duration than susceptible ones. The reproductive days and hatching success showed significant lower values revealing reproductive costs for the resistant groups. Matrix analysis showed lower population growth rates for the resistant groups. Our results support developmental and reproductive costs for pyrethroid‐resistant individuals. This trait could be interpreted as lower population recovery ability for pyrethroid‐resistant individuals compared to susceptible insects after alternative vector control actions. [ABSTRACT FROM AUTHOR]

Background and aims: Herbarium specimens were reviewed as part of broader project that deals with the diversity of bryophytes from the Chaco province (Argentina). One of the samples matched the description of Timmiella acaulon, a species poorly known. The aim of this work is to record T. acaulon as new to Chaco Province and to describe morphologically and illustrate in detail this remarkable species. M&M: Herbarium samples were analyzed with standard techniques for bryophytes. Examination with scanning electron microscope was made using samples mounted directly on double-sided tape and coated in gold-palladium. Results: Timmiella acaulon is newly registered for Chaco province. A complete and detailed morphological description, and illustrations are here presented. Conclusions: Due to the rediscovery of the species more than 100 years after its original description, the distribution range of T. acaulon is extended to northeastern Argentina, and details of morphological characters of systematic value are provided. [ABSTRACT FROM AUTHOR]

Backgrounds: Neltuma alba is one of the most important native woody species in Argentina in the Dry Chaco, part of the Argentine Mesopotamia and the Paraguayan Chaco. It shows great variability due to interspecific hybridization and introgression associated with protogyny and self-incompatibility systems. This species is adapted to arid and semi-arid climates with saline and degraded soils. Environmental heterogeneity and wide distribution may result in local adaptation and autocorrelated spatial patterns in genetic and quantitative variables. Aim: To analyze the spatial structure in provenances of N. alba influenced by isolation by distance in the Gran Chaco Region. M&M: This work studied spatial structure in seven provenances of N. alba from the Dry and Humid Chaco regions, based on fifteen foliar, fruit and germination traits in 68 individuals, together with five environmental variables. Results and Conclusion: univariate statistical analyses showed significant or highly significant differences among provenances. According to Moran’s I index phenotypic and geographical distances are significantly autocorrelated for the first distance class (0-0.643 km). Partial Mantel test showed significant correlation for the first two distance classes. The overall analysis showed that 11 of the analyzed traits showed significant spatial autocorrelation. The local spatial analysis indicated that for several traits their hot spots of high similarity between neighboring individuals and cold spots where nearby individuals are highly differentiated. [ABSTRACT FROM AUTHOR]

The Bromeliaceae are known for providing numerous ecosystem services. Tank bromeliads that collect water in the bases of their leaves have been an important source of water for people in semiarid regions such as the Gran Chaco. In this large area characterized by xerophytic vegetation grows Aechmea distichantha, the only Chaquenian terrestrial tank bromeliad. We carried out a literature review on water consumption from this tank bromeliad by people in this region. Then, we analyzed the variations in the amount of water stored in the tanks of plants from observational studies as well as the effects of the amount and frequency of water addition on the hydrology of water retained in the tank from an irrigation experiment study. We found 85 reports on the consumption of water from A. distichantha plants by people, including several Indigenous Groups, Criollos, and Soldiers. According to these reports, the tank accumulates about a liter of relatively fresh and clear water that lasts for several weeks. Our observational study showed a large variation in the amount of water held in the tank among years and sites, and our irrigation experiment showed that even plants receiving low and unevenly distributed rainfall conserved some water in their tanks. All these results support the importance of this tank bromeliad for surviving when moving in Eastern Chaco during dry periods until the beginning of the twentieth century. At present, it seems that people living in sedentarism no longer frequently use it for water provision, highlighting that the relative importance of a plant species for providing ecosystem services depends on the historical context. [ABSTRACT FROM AUTHOR]

During the Quaternary, Chaco Phytogeographic Domain (Chaco) flora in subtropical South America experienced temperature and humidity fluctuations, primarily driven by wind dynamics, leading to significant shifts in species distribution. The palm Butia yatay is endemic to the Chaco and thrives in areas characterized by a warm–rainy climate and mostly restricted to sandy soils. To investigate the current geographic distribution of suitable habitat for B. yatay while assessing the significance of soil variables, we employed two distinct algorithms in species distribution modeling (SDM). We also determined whether the distribution of B. yatay has changed since the Pleistocene and whether these changes align with previously proposed Pleistocene refugia. In the present SDMs, we considered two separate sets of predictors, one set with bioclimatic variables only and the other set with bioclimatic topographic and soil variables. Additionally, we reconstructed the historical geographic distribution of suitable habitats using bioclimatic data. Our results suggested that the primary determinants of B. yatay's current distribution include precipitation and temperature of the driest month and soil cation exchange capacity. Incorporating soil variables affected the estimated size and range of suitable areas. Projections into the past indicated similar suitable habitat distributions during interglacial periods compared with the present. During the Last Glacial Maximum, climatically suitable habitat may have shifted northward, partially overlapping with previously suggested Pleistocene refugia located between the Paraná and Uruguay Rivers. These findings indicate the main factors driving the distribution and ecology of B. yatay and enhance understanding of subtropical flora shifts during the Quaternary. The approach also may prove valuable for other studies within the Chaco. [ABSTRACT FROM AUTHOR]

The Huayquerian Stage of the South American chronostratigraphic scheme (named for the Huayquerías del Este, Argentina) was originally based on a poorly known mammal association of six taxa from the Huayquerías Formation. We studied the geology, age and fauna of the Neogene sequence in this area, including the Huayquerías, Tunuyán and Bajada Grande formations. The sequence comprises a monotonous succession of synorogenic epiclastic sediments deposited under arid to semi‐arid conditions. Zircon U–Pb dates from 10 tuffaceous levels (7.2–1.6 Ma) place deposition of the Huayquerías Formation during the late Tortonian or Messinian to early Zanclean, the Tunuyán Formation during the Zanclean–Piacenzian, and the Bajada Grande Formation during the Piacenzian–Calabrian. We present 43 and 31 new mammal taxon records for the Huayquerías and Tunuyán formations, respectively. Progressive faunal change was observed along the sequence. The first records of the Chaco tortoise Chelonoidis chilensis and the notoungulate Xotodon major, and the latest records of Interatheriidae and Typotheriopsis (notoungulates), Metacaremys calfucalel, Phtoramys hidalguense and Lagostomus pretrichodactyla (rodents), Chasicotatus ameghinoi and Macroeuphractus morenoi (xenarthrans) are reported. The faunal associations of the Huayquerías and lower Tunuyán formations are highly similar to each other, and to other coeval localities in Argentina. The Macroeuphractus morenoi Assemblage Biozone is proposed as the basis for redefining the Huayquerian Stage, due to the co‐occurrence of three taxa with wide geographical distribution in southern South America: Macroeuphractus morenoi, Pseudotypotherium subinsigne and Lagostomus pretrichodactyla. The age of this biozone is constrained at c. 8–5 Ma in its type area. [ABSTRACT FROM AUTHOR]

Abstract Background The Gran Chaco region is a major hotspot of Chagas disease. We implemented a 9-year program aimed at suppressing house infestation with Triatoma infestans and stopping vector-borne transmission to creole and indigenous (Qom) residents across Pampa del Indio municipality (Argentine Chaco). The aim of the present study was to assess the intervention effects on parasite-based transmission indices and the spatial distribution of the parasite, and test whether house-level variations in triatomine infection with Trypanosoma cruzi declined postintervention and were influenced by household ethnicity, persistent infestation linked to pyrethroid resistance and other determinants of bug infection. Methods This longitudinal study assessed house infestation and bug infection with T. cruzi before and after spraying houses with pyrethroids and implemented systematic surveillance-and-response measures across four operational areas over the period 2007–2016. Live triatomines were individually examined for infection by optical microscopy or kinetoplast DNA (kDNA)-PCR and declared to be infected with T. cruzi when assessed positive by either method. Results The prevalence of infection with T. cruzi was 19.4% among 6397 T. infestans examined. Infection ranged widely among the study areas (12.5–26.0%), household ethnicity (15.3–26.9%), bug ecotopes (1.8–27.2%) and developmental stages (5.9–27.6%), and decreased from 24.1% (baseline) to 0.9% (endpoint). Using random-intercept multiple logistic regression, the relative odds of bug infection strongly decreased as the intervention period progressed, and increased with baseline domestic infestation and bug stage and in Qom households. The abundance of infected bugs and the proportion of houses with ≥ 1 infected bug remained depressed postintervention and were more informative of area-wide risk status than the prevalence of bug infection. Global spatial analysis revealed sharp changes in the aggregation of bug infection after the attack phase. Baseline domestic infestation and baseline bug infection strongly predicted the future occurrence of bug infection, as did persistent domestic infestation in the area with multiple pyrethroid-resistant foci. Only 19% of houses had a baseline domestic infestation and 56% had ever had ≥ 1 infected bug. Conclusions Persistent bug infection postintervention was closely associated with persistent foci generated by pyrethroid resistance. Postintervention parasite-based indices closely agreed with human serosurveys at the study endpoint, suggesting transmission blockage. The program identified households and population subgroups for targeted interventions and opened new opportunities for risk prioritization and sustainable vector control and disease prevention. Graphical abstract

En este escrito se revisan algunos fenómenos que ponen de manifiesto cómo el estudio de las lenguas particulares permite descubrir y determinar, entre otras relaciones, aquellos que los sujetos manifiestan lingüísticamente en relación con los cuerpos propios y ajenos, los cuerpos sociales y las entidades no humanas, siempre referenciando el discurso a partir del propio yo y su modo de percibirse. Se considera que los estudios morfológicos, sintácticos y semánticos de distintos fenómenos lingüísticos son necesarios para observar marcas de comportamiento lingüístico que motivan y/o son motivados por una concepción de mundo específico. Se centra la atención en fenómenos lingüísticos que determinan y definen un modo de pensar, una concepción del mundo y de los vínculos que se fundamentan al interior de la comunidad, los elementos que son relevantes culturalmente para los hablantes y que responden, también, a procesos históricos de conformación de la identidad de un pueblo. Para llevar adelante este objetivo, se focaliza en lenguas originarias sudamericanas, con mayor detalle en la lengua mocoví (familia Guaycurú) a cuyos datos se accedió en su mayoría de primera mano mediante trabajo directo en territorio durante períodos discontinuos ya través del contacto con hombres y mujeres hablantes nativas.

Between 2011 and 2022, the Universidad del Monte (a Wichí community and organisation neighbouring Misión Chaqueña, Salta, Argentina) has developed a series of activities that attempt to recover and reproduce Wichí ways of life, as part of their indigenous rights. In this study, I propose to reflect on the strategies of Wichí social reproduction and, in relation to this, the meanings that the rights recognised by international organisations and the State (in this case, Argentinean and Salta) take on in everyday Wichí life in the Chaco-Salta territory. The ethnographic work carried out throughout the research allowed us to explore and learn about different Wichí organisational processes, of which the Universidad del Monte is only one, but which we consider to be a fundamental node for reflecting on the meanings of their socio-territorial struggles in relation to the meaning attributed to indigenous rights. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)