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This paper develops a spatial rural economy model of adaptation to climate change that accounts for a multitude of rural enterprises across a diversity of ecosystems in South America using household surveys. We model adoptions of crops, livestock, and forests. Both specialized and diversified enterprises are modelled. This paper finds that livestock, forests, and a diversification into crops, livestock, and forests are key adaptation strategies. Under the UKMO (United Kingdom Meteorological Office) scenario, a livestock-only enterprise would expand by 4 per cent, a crops-livestock-forests by 3 per cent, and a forests-only by 3 per cent. Adaptation behaviours are closely tied with ecosystem changes under global warming. A livestock-only would increase especially in the grasslands. A crops-livestock-forests enterprise expands into xeromorphic forests. A crops-livestock expands in Andean grasslands and tall grasslands. A forests-only expands in the coasts and woody zones. A crops-only enterprise decreases across South America. Resumen Utilizando encuestas a hogares, en este artículo se desarrolla un modelo espacial de economía rural para la adaptación al cambio climático, con la capacidad de representar una gran cantidad de empresas rurales dentro de una diversidad de ecosistemas en América del Sur. Se modeliza la adopción de cultivos, ganado y bosques. Se modelizan tanto empresas especializadas como diversificadas. El artículo encontró que el ganado, los bosques, y una diversificación en cuanto a cultivos, ganado y bosques son estrategias claves de adaptación. Bajo un escenario propuesto por la Oficina Meteorológica del Reino Unido (UKMO, siglas en inglés), una explotación dedicada solamente a la ganadería aumentaría en un 4 por ciento, una dedicada a cultivos-ganadería-bosques un 3 por ciento, y una dedicada exclusivamente a bosques un 3 por ciento. Los comportamientos para la adaptación están estrechamente ligados a cambios en los ecosistemas debidos al calentamiento global. Una explotación exclusivamente ganadera aumentaría especialmente en el ecosistema de pastizal. Una explotación de cultivos-ganadería-bosques podría expandir en bosques xeromórficos. Una explotación basada en cultivos-ganado expandiría en áreas de pastizales Andinos y pastizal alto. Las explotaciones basadas solamente en bosque expandirían en las costas y zonas boscosas. Una explotación exclusivamente de cultivos disminuiría en América del Sur. [ABSTRACT FROM AUTHOR]

‘geographical pivot of history’ concept, subsequently developed into his famous‘Eurasian heartland thesis’, marginalizes South America, yet his ideas have attracted considerable interest there, including interpretations (and fantasies) of a‘South American heartland’. This paper examines the reception of Mackinder's ideas in Latin American geopolitics and how his heartland thesis was adapted for the South American context. It traces the roots of this adaptation in earlier South American geopolitical writing, and examines these ideas of counter-insurgency policies and global geopolitical strategies, analysing their relationship to military and anticommunist perspectives. [ABSTRACT FROM AUTHOR]

This paper develops a microeconometric analysis of adapting portfolios in response to climate change using information on South American farmers' adoption of agricultural systems taken from approximately 2,000 household surveys. The results show that farmers in a hotter climate prefer a mixed system over specialized systems either in crops or livestock. Under a hot and dry scenario, the land values of all three systems would fall, but the damage would be much smaller in the mixed system (−10%) than for the farms specializing in crops (−20%). Farmers are predicted to lose 8% of their land's value under the Canadian Climatic Center (CCC) scenario, but only 2% under the Parallel Climate Model (PCM). Losses would increase to 18% if they do not adapt. [ABSTRACT FROM PUBLISHER]

Mountainous grasslands in South America, characterized by their high diversity, provide a wide range of contributions to people, including water regulation, soil erosion prevention, livestock feed provision, and preservation of cultural heritage. Prior research has highlighted the significant role of grazing in shaping the diversity and productivity of grassland ecosystems, especially in highly productive, eutrophic systems. In such environments, grazing has been demonstrated to restore grassland plant diversity by reducing primary productivity. However, it remains unclear whether these findings are applicable to South American mountainous grasslands, where plants are adapted to different environmental conditions. To address this uncertainty, we conducted a meta‐analysis of experiments excluding livestock grazing to assess its impact on plant diversity and productivity across mountainous grasslands in South America. In alignment with studies in temperate grasslands, our findings indicated that herbivore exclusion resulted in increased aboveground biomass but reduced species richness and Shannon diversity. The effects of grazing exclusion became more pronounced with longer durations of exclusion; nevertheless, they remained resilient to various climatic conditions, including mean annual precipitation and mean annual temperature, as well as the evolutionary history of grazing. In contrast to results observed in temperate grasslands, the reduction in species richness due to herbivore exclusion was not associated with increased aboveground biomass. This suggests that the processes governing (sub)tropical grassland plant diversity may differ from those in temperate grasslands. Consequently, further research is necessary to better understand the specific factors influencing plant diversity and productivity in South American montane grasslands and to elucidate the ecological implications of herbivore exclusion in these unique ecosystems. [ABSTRACT FROM AUTHOR]

The oldest Cenozoic mammalian assemblages in South America have been recovered from levels of the Hansen Member of the Salamanca Formation, Punta Peligro locality in Argentina, and from the Santa Lucía Formation in Tiupampa, Bolivia. These faunas led to the recognition of the Peligran and Tiupampan South American Land Mammal Ages (SALMAs), each alternatively regarded as the oldest Paleocene SALMA. Due to the lack of radioisotopic dates for mammals bearing levels at these localities, no agreement has been reached yet about their relative ages. In this paper, the role of mammal faunas in age inference is discussed. Analysis of the SALMAs shows that the presence of non-therian mammals in the Peligran is of little consequence to the biochronological evaluation, reflecting instead a relict Mesozoic distribution. In contrast, therian mammals are particularly important in that (1) they were Lauraisan immigrants and (2) they support direct comparisons between the Tiupampa and Punta Peligro faunas. Parsimony and cluster analysis were used to quantitatively test hypotheses concerning the relative age of the Peligran and Tiupampan SALMAs. Our results support the hypothesis that the Tiupampan SALMA (early Danian) is older than the Peligran SALMA (early Selandian). This alignment results in an interpretation of the evolutionary history of South American land mammals that is more straightforward than the alternative. [ABSTRACT FROM AUTHOR]

Juan Isern collected ca. 25,000 plant specimens during the Pacific Scientific Commission to South America between 1862 and 1866, but unfortunately he died the same year the expedition returned to Spain. In Chile, lsern exchanged specimens with Philippi, who later described three new species based on those collections which are all deposited at SGO. In the early 1930s, José Cuatrecasas worked intensively with the Isern collections at MA, where most of Isern's South American specimens are deposited. Cuatrecasas, Trelease, Sleumer, Standley and Yuncker described several new species and other taxa using Isern collections as type material. A total of 47 species, 21 varieties and 7 forms were described in 9 families, principally in the Asleraceae, Piperaceae and Gesneriaceae based on Isern collections. Here, the nomenclature of all Isern type specimens is studied for these 75 names. Lectotype specimens for the names of four species, three varieties and five forms described by Cuatrecasas and one species described by Trelease are designated in the present paper. [ABSTRACT FROM AUTHOR]

Aim Species richness depends on climate and land use. Maintaining locations with favourable climate and land-use patterns is critical for protecting biodiversity because the loss of either can reduce the species richness that an area supports. Currently, the Guiana Shield (GS) receives abundant precipitation and has relatively light land use. For species richness this constitutes a good–good combination of climate and land use, respectively. In contrast, much of eastern Brazil receives low levels of precipitation and has heavy land use, which is a bad–bad combination for species richness. Thus, the current distribution of precipitation and land use in northern South America is relatively favourable for biodiversity. Palaeoclimate and model studies suggest, however, that the precipitation patterns for the two regions have switched before and could switch in response to greenhouse gas emissions. This paper examines the potential consequences of reconfiguring climate with respect to existing land-use patterns using South America as an example. Location South America north of 20° S and east of the Andes. Methods Ecosystem structure and function are modelled under (1) historical climate and (2) altered precipitation following a shift in the location of the Inter-Tropical Convergence Zone (ITCZ). The distribution of precipitation, biomes, net primary productivity (NPP) and land use are then used to predict levels of species richness under the two climate scenarios. Results Climate changes could shift the distribution of vegetation and NPP such that conditions favourable for species richness in the GS region disappear. If land-use patterns were not prohibitive in eastern Brazil, the improved climate conditions there could compensate for the GS loss (assuming migratory barriers are overcome). Instead, existing land-use patterns cause the combined species richness projected for the two regions to plummet. Main conclusions Human activities will alter current configurations of land use and climate throughout the world. For species richness, new configurations are likely to include both positive and negative combinations of climate and land use. However, the irreversibility of past extinctions due to land-use patterns loads the dice against species richness. [ABSTRACT FROM AUTHOR]

Through analysis of fossil records, the aim of this paper is to show that fossil representatives of at least three land-mammal clades (pitheciine atelid primates, heteropsomyine echimyid rodents, and megalonychid phyllophagan xenarthrans) that once lived in the Greater Antilles are as old as, if not older than,‘first’ occurrences of these same groups on the South American mainland.Greater Antilles, South America, Antarctic Peninsula.Analysis of Cenozoic land-mammal fossil records for the three areas.Comparison reveals an interesting similarity to the Tertiary vertebrate palaeontological record for the Antarctic Peninsula (Seymour Island), in the sense that the latter also includes early (Eocene) representatives of some typical‘South American’ groups (e.g. meridiungulates, sloths, certain marsupial groups).Given how limited the Antillean and Antarctic records are in quantity and quality, it seems unlikely that these‘first’ appearances have much bearing on real origins (basal divergences). Rather, it suggests that the fossil basis for interpreting the origin and earliest diversification of‘South American’ clades during the latest Cretaceous/early Cenozoic is probably even scantier than generally realized. In particular, the Antillean record strengthens arguments that some crown-group continental lineages are considerably older than fossil evidence currently allows– a point increasingly (if unevenly) supported by molecular studies of many of the same clades. [ABSTRACT FROM AUTHOR]

Copyright of Austral Ecology 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.)

Copyright of Conservation Biology 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.)

Premise: Pilosocereus (Cactaceae) is an important dry forest element in all subregions and transitional zones of the neotropics, with the highest diversity in eastern Brazil. The genus is subdivided into informal taxonomic groups; however, most of these are not supported by recent molecular phylogenetic inferences. This lack of confidence is probably due to the use of an insufficient number of loci and the complexity of cactus diversification. Here, we explored the species relationships in Pilosocereus in more detail, integrating multilocus phylogenetic approaches with the assessment of the ancestral range and the effect of geography on diversification shifts. Methods: We used 28 nuclear, plastid, and mitochondrial loci from 54 plant samples of 31 Pilosocereus species for phylogenetic analyses. We used concatenated and coalescent phylogenetic trees and Bayesian models to estimate the most likely ancestral range and diversification shifts. Results: All Pilosocereus species were clustered in the same branch, except P. bohlei. The phylogenetic relationships were more associated with the geographic distribution than taxonomic affinities among taxa. The genus began diversifying during the Plio‐Pleistocene transition in the Caatinga domain and experienced an increased diversification rate during the Calabrian age. Conclusions: We recovered a well‐supported multispecies coalescent phylogeny. Our results refine the pattern of rapid diversification of Pilosocereus species across neotropical drylands during the Pleistocene and highlight the need for taxonomic rearrangements in the genus. We recovered a pulse of diversification during the Pleistocene that was likely driven by multiple dispersal and vicariance events within and among the Caatinga, Cerrado, and Atlantic Forest domains. [ABSTRACT FROM AUTHOR]

Semipalmated sandpipers are Arctic breeding shorebirds that migrate to South America during the non‐breeding season. Little work has been done to understand the daily movements, foraging habits and metabolic state of this species on stationary nonbreeding grounds. Our work was conducted at the Banco dos Cajuais Western Hemisphere Shorebird Reserve Network (WHSRN) site in Northeast Brazil. We captured semipalmated sandpipers in February and March 2019 and 2020 and attached nanotags to monitor their daily movements. Blood samples were taken to measure plasma triglycerides (an index of fattening rate). We also conducted behavioral observations on foraging birds. Using tracking data we determined that most semipalmated sandpipers appeared to use sunrise/sunset as an indicator for movement between salina and tidal flat habitats, and a smaller portion used tidal height. We found birds spent similar amounts of time foraging on tidal flats and in salinas, though different foraging modes were used. Plasma triglyceride measures suggest semipalmated sandpipers had not started preparing to migrate when sampled. We successfully tracked semipalmated sandpipers to North America during northward migration in 2020, detecting eight within the United States. Tracking results suggest many stopped elsewhere in South America to fuel for migration, though some may have fueled at the Banco dos Cajuais. By demonstrating substantial use of both natural and altered habitats in the region by migrant semipalmated sandpipers, these data highlight the need for broader conservation measures throughout coastal regions of South America. [ABSTRACT FROM AUTHOR]

The Madden Julian Oscillation (MJO) is the main source of intraseasonal variability in the tropics. MJO modulates rainfall in remote areas in the Southern Hemisphere by exciting tropical and extratropical wave trains. We use newly released reanalysis data to analyze how the Quasi‐Biennial Oscillation (QBO) can influence the MJO's effects over the Southern Hemisphere, focusing on precipitation anomalies over South America. The anomalies in the intensity of the South Atlantic Convergence Zone (SACZ) and precipitation over Southeastern South America during MJO phases 1 and 4 are intensified during the easterly QBO. The extratropical wave train excited by the anomalous convection over the maritime continent during MJO phase 4 is affected by the QBO, with a stronger, better‐defined pattern during westerly QBO. The conclusions are supported by a perturbation experiment of a case study, conducted using a high‐top atmospheric global climate model where the QBO and MJO are controlled. Plain Language Summary: Subseasonal to seasonal prediction remains challenging in the current forecast models. Previous studies have shown that the Quasi‐Biennial Oscillation (QBO) can influence the intensity and development of the Madden Julian Oscillation (MJO). Here, the consequences of this modulation on the remote effects of the MJO in the Southern Hemisphere are analyzed using reanalysis and perturbation experiments in an atmospheric global climate model. The rainfall anomalies related to the MJO in South America are more intense and widespread during easterly QBO over the South Atlantic Convergence Zone and southern Brazil than during westerly QBO. Thus, the inclusion of the state of the QBO in the estimate of the expected rainfall associated with the MJO is crucial to improve forecasts in the region. Key Points: The Quasi‐Biennial Oscillation (QBO) modulates the impacts of the Madden Julian Oscillation (MJO) in the Southern HemisphereMJO‐related rainfall anomalies in the South Atlantic Convergence Zone are intensified during easterly QBOEThe extratropical wave train forced by the anomalous convection in MJO phase 4 is intensified under QBOW [ABSTRACT FROM AUTHOR]

ABSTRACT Aim To investigate whether trait-habitat relations in biological communities converge across three global regions. The goal is to assess the role of habitat templets in shaping trait assemblages when different assembly mechanisms are operating and to test whether trait-habitat relations reflect a common evolutionary history or environmental trait filters. Location Guiana Shield, South America; Upper Guinea Forest Block, West Africa; Borneo rain forests, Southeast Asia. Methods We compared large anuran amphibian data sets at both the regional and cross-continental scale. We applied a combination of three-table ordinations (RLQ) and permutation model-based multivariate fourth-corner statistics to test for trait-habitat relationships at both scales and used phylogenetic comparative methods to quantify phylogenetic signal in traits that enter these analyses. Results Despite the existence of significant trait-habitat links and congruent trait patterns, we did not find evidence for the existence of a universal trait-habitat relationship at the assemblage level and no clear sign for cross-continental convergence of trait-habitat relations. Patterns rather varied between continents. Despite the fact that a number of traits were conserved across phylogenies, the phylogenetic signal varied between regions. Trait-habitat relations therefore not only reflect a common evolutionary history, but also more recently operating environmental trait filters that ultimately determine the trait composition in regional assemblages. Main conclusions Integrating trait-habitat links into analyses of biological assemblages can enhance the predictive power and general application of species assembly rules in community and macroecology, particularly when phylogenetic comparative methods are simultaneously applied. However, in order to predict trait composition based on habitat templets, trait-habitat links cannot be assumed to be universal but rather have to be individually established in different regions prior to model building. Only then can direct trait-based approaches be useful tools for predicting fundamental community patterns. [ABSTRACT FROM AUTHOR]

Precipitation predictions in the sub-seasonal timescale are very important for several sectors such as agriculture and energy in regions of South America that are very much affected by precipitation extremes, both excess and lack of rain. The aim of the present study is to investigate the ability of two S2S project models (ECMWF and NCEP) to detect the Southern Hemisphere teleconnections in model hindcasts and the associated anomalous precipitation over South America. The period of analyses is 1999-2010 for the austral summer season (December-January-February). Both models represented adequately the Southern Annular Mode (SAM) pattern in predictions up to 4 weeks ahead and the Pacific South America (PSA) pattern up to 3 weeks. Atmospheric variables of observed extreme cases of SAM were well predicted by the two models, 2 and 3 weeks in advance. The models predicted well atmospheric variables in observed extreme cases of PSA, 2 weeks in advance and with less intensity in the third week. Precipitation anomaly signals associated with these modes were well predicted 2 weeks in advance, although with different intensities. The good ability of the models hindcast in predicting teleconnection patterns and precipitation anomalies over South America provides more confidence to use predictions at sub-seasonal timescale. [ABSTRACT FROM AUTHOR]

Conservation policies often promote land privatization to reduce incentives for deforestation. However, empirical evidence on the relationship between land‐tenure form and forest conservation outcomes is inconclusive. We combined key informant mapping and geospatial analyses to test the association between the area under tenure and the area deforested by extra‐local private and local nonprivate agents in the Argentine Dry Chaco over four decades (1976–2016). The study area is a typical commodity production frontier within a global deforestation hotspot. We found a strong spatial and temporal coupling between the area under tenure and the area deforested by extra‐local private agents from 1987 to 2006, when a 59% increase in the former was accompanied by a 508% increase in the latter. Local private agents maintained high levels of forest cover, similarly to local nonprivate agents. Our findings have implications for the adaptive design of the Forest Law in the Argentine Dry Chaco. [ABSTRACT FROM AUTHOR]

With increasing availability of plant distribution data, the information about global plant diversity is improving rapidly. Recently, Ulloa Ulloa et al. (2017) presented the first comprehensive overview of the native vascular flora of the Americas, yielding a total count of 124,993 native species. Of these, 51,241 occur in North America and 82,052 in South America. By combining these data with the information in the Global Naturalized Alien Flora (GloNAF) database of naturalized alien floras, we point out that for a complete picture of the regional and continental plant richness, the naturalized alien species need to be considered. Ignoring this novel component of regional floras can lead to an inaccurate picture of overall change in biodiversity in the Anthropocene. We show that North and South America might face contrasting challenges in terms of potential threats to biodiversity posed by alien plant species, because of the different past and present dynamics of invasions and predictions of future development. In total, there are 7,042 naturalized alien plants occurring in the Americas, with 6,122 recorded in North America and 2,677 in South America; if only introductions from other continents are considered additions to the native continental flora make up 6.9 and 1.4 %, respectively. Nevertheless, predictions of naturalized plant trajectories based on global trade dynamics and climate change suggest that considerable increases in naturalized plant numbers are expected in the next 20 years for emerging South American economies, which could reverse the present state. [ABSTRACT FROM AUTHOR]

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Morphology and anatomy of a fossil nymphaealean plant, Jaguariba wiersemana gen. nov. et sp. nov. from the late Early Cretaceous of northeastern Brazil, and extant aquatic flowering plants are comparatively studied. Characteristic features indicate that Jaguariba gen. nov. is a member of Nymphaeaceae, and may belong to Nymphaeoideae. The occurrence of both Nymphaeaceae and Cabombaceae (e.g., Pluricarpellatia peltata) in the Lower Cretaceous contradicts recent molecular dat-ing implying a Late Cretaceous--Early Tertiary divergence for those families. Furthermore, the morphology of the fossil and sedimentologic and taphonomic data indicate that Jaguariba gen. nov. had an aquatic ecology similar to living Nymphaeaceae. Thus the taxon was part of the aquatic vegetation of the Crato lake in association with Pluricarpellatia peltata, an earlier de-scribed cabombaceaen aquatic angiosperm. [ABSTRACT FROM AUTHOR]

The tribe Liabeae (Compositae) contains ca. 175 species distributed in 18 genera and its members occupy a variety of habitats in the Andes of South America as well as in Mexico, Central America, and the West Indies. The tribe is recognizable by a combination of morphological characters. DNA sequence data from the nuclear ribosomal ITS region and three chloroplast regions (trnL-F, 3' end of ndhF, matK; a total of more than 5 kb of sequence data) were used to infer a phylogeny. The data were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. The results support the monophyly of the tribe and show a consistent placement for all genera except Cacosmia. Four well-supported clades are recovered in the remainder of the tribe, all recognized as subtribes. Liabineae (Ferreyranthus, Dillandia, Oligactis, Sampera, Liabum) are the sister group of the rest of the tribe. Sinclairineae (Sinclairiopsis and Sinclairia with segregates Liabellum and Megaliabum) are the sister group of Munnoziinae (Chrysactinium nested inside Munnozia s.l.) plus Paranepheliinae (Stephenbeckia, Microliabum, Pseudonoseris, Paranephelius, Chionopappus, Philoglossa, Erato). Cacosmia is placed as the sister group of either all the rest of the tribe or of subtribe Liabineae; morphologically its characters are either autapomorphic or plesiomorphic. Bishopanthus could not be confidently placed in any of the subtribes; it is only known from scraps of the type and a molecular study is not possible. The phylogeny slightly alters previous assumptions about the biogeography and it seems that Liabeae originated in the central and northern Andes and spread north and south with several independent introductions into Mexico and Central America and one into the Caribbean. With the exception of the Liabeae (Andes) and Moquineae (Brazil), all of the tribes in the subfamily Cichorioideae are either restricted to or have their basal grade in Africa. [ABSTRACT FROM AUTHOR]

The Chiliotrichum group (Compositae: Astereae) is an informal taxonomic group consisting of shrubby daisies that grow mainly in the Andean and Patagonian regions of South America; it is composed of 31 species in 11 genera: Aylacophora, Cabreraea, Chiliotrichiopsis, Chiliophyllum, Chiliotrichum, Haroldia, Katinasia, Lepidophyllum, Llerasia, Nardophyllum, and Ocyroe. We analyzed phylogenetic relationships in the Chiliotrichum group using five DNA regions from two plant genomes: the plastid trnL-trnF and rpl32-trnL(UAG) spacers, the rpl16 intron, and the nuclear ribosomal internal and external transcribed spacers, ITS and ETS respectively. The dataset includes 21 ingroup species representing all the genera, and 10 outgroup species belonging to six genera. Maximum parsimony, maximum likelihood, and Bayesian inference analyses performed on the chloroplast and nuclear data support the monophyly of the group. The four major clades recovered on the basis of the combined nuclear evidence (ITS+ETS) are: (1) Llerasia clade, (2) Nardophyllum clade, (3) Chiliotrichum clade, and (4) a clade formed by Nardophyllum+Llerasia clades. As regards the status of the four non-monospecific genera, Chiliotrichum (2 spp.) and Llerasia (14 spp.) were recovered as monophyletic, whereas the other two, Nardophyllum (5 spp.) and Chiliotrichiopsis (3 spp.), were not recovered as monophyletic. These two are nonetheless recognized as distinct genera because of robust morphological support despite the lack of resolution in the phylogeny based solely on sequence data. The rest of the genera composing the group are monospecific, and they are scattered among the major clades in the group. The only genus with no clear position is Haroldia. An analysis of the morphological data shows that the presence of paleae, believed to function as a defensive structure for the protection of the achenes, is well correlated with other derived head and floret traits such as the number of florets per head and the type of pappus. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the extent of racial gaps in child health insurance coverage in South America and study the contribution of wealth, human capital, and other household characteristics to accounting for racial disparities in insurance coverage. Data Sources/Study Setting. Primary data collected between 2005 and 2006 in 30 pediatric practices in Argentina, Brazil, Ecuador, and Chile. Design. Country-specific regression models are used to assess differences in insurance coverage by race. A decomposition model is used to quantify the extent to which wealth, human capital, and other household characteristics account for racial disparities in insurance coverage. Data Collection/Extraction Methods. In-person interviews were conducted with the mothers of 2,365 children. Principal Findings. The majority of children have no insurance coverage except in Chile. Large racial disparities in insurance coverage are observed. Household wealth is the single most important household-level factor accounting for racial disparities in coverage and is significantly and positively associated with coverage, followed by maternal education and employment/occupational status. Geographic differences account for the largest part of racial disparities in insurance coverage in Argentina and Ecuador. Conclusions. Increasing the coverage of children in less affluent families is important for reducing racial gaps in health insurance coverage in the study countries. [ABSTRACT FROM AUTHOR]

Aim We evaluate the extent to which the tropical conservatism hypothesis can explain the evolutionary development of the Muscidae. Furthermore, we compare the geographical patterns of muscid phylogenetic structure with biogeographical regions that have been identified for Neotropical insects. Location Central and South America. Methods We modelled the geographic distributions of 658 species using M axent and 19 environmental variables. A generic-level supertree of the Muscidae was assembled using matrix representation with parsimony and used to map the geographic pattern of mean root distance (MRD), a metric of the relative evolutionary development of assemblages. Regression models (ordinary least squares and regression trees) were used to examine temperature and other environmental correlates of MRD to explore potential environmental drivers of muscid diversification. We used the regression tree results to recognize variable intervals that best explained MRD, and these intervals were mapped to recognize and compare with biogeographical regions of Neotropical insects. Results The geographic pattern of MRD was consistent with the tropical conservatism hypothesis: species in genera that diversified relatively early, as measured by their distance from the tree root, dominate lowland tropical South America, whereas species in genera that diversified more recently occupy extra-tropical areas, sub-Antarctic areas and the Andean highlands. Temperature was the strongest correlate of MRD. Three biogeographical regions were recognized and they coincided with two regions known for insects. Main conclusions Evolutionary responses of muscid flies to post-Eocene climate change taking the form of an expansion of a tropical group into regions with colder climates may be fundamental to explaining their distribution in the Neotropics. Our biogeographical regions delimited by temperature and the phylogenetic metric, surrogates of the tropical conservatism hypothesis, were very similar to general insect patterns, supporting the 'tropical origin and evolutionary response to climate cooling' as a broadly based historical narrative for the Neotropics. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology 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.)

•We used a climate–vegetation–natural fire (CVNF) conceptual model to evaluate the sensitivity and vulnerability of forest, savanna, and the forest–savanna transition to environmental changes in tropical South America. •Initially, under current environmental conditions, CVNF model results suggested that, in the absence of fires, tropical forests would extend c. 200 km into the presently observed savanna domain. •Environmental changes were then imposed upon the model in temperature, precipitation and lightning strikes. These changes ranged from 2 to 6°C warming, +10 to −20% precipitation change and 0 to 15% increase in lightning frequency, which, in aggregate form, represent expected future climatic changes in response to global warming and deforestation. •The most critical vegetation changes are projected to take place over the easternmost portions of the basin, with a widening of the forest–savanna transition. The transition width would increase from 150 to c. 300 km, with tree cover losses ranging from 20 to 85%. This means that c. 6% of the areas currently covered by forests could potentially turn into grass-dominated savanna landscapes. The mechanism driving tree cover reduction consists of the combination of less favorable climate conditions for trees and more fire activity. In addition, this sensitivity analysis predicts that the current dry shrubland vegetation of northeast Brazil could potentially turn into a bare soil landscape. [ABSTRACT FROM AUTHOR]

The taxonomy, biostratigraphical and palaeogeographical distribution of the Lower Ordovician graptolite genus Bryograptus is evaluated. Bryograptus is recognized as a distinct triradiate anisograptid with a multiramous, pendent rhabdosome. The species of the genus Bryograptus can be interpreted as shallow water faunal elements with a strongly limited biogeographical distribution to the Atlantic Faunal Realm. Bryograptus is restricted to a narrow interval in the Upper Tremadocian, the Bryograptus Biozone of Scandinavia and South America (Argentina), making it a taxon with a high potential for precise biostratigraphical correlations. The proximal end development can be used to differentiate the genus Bryograptus from other pendent multiramous graptoloid genera with a homoplastic rhabdosome development. Characteristics of the proximal end development and structure easily differentiate these genera in relief specimens, but not in flattened material. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology 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 trilophodont gomphothere group is a monophyletic group of genera separated from other proboscideans by one synapomorphy, the presence of trefoil-shaped wear patterns on the occlusal surfaces of their teeth. These wear patterns vary from being just a single trefoil, through double trefoils, to more complex combinations of trefoils. They are present in all of the genera studied here. Our cladistic analysis makes use of 12 genera as terminal taxa. It was performed using 43 cranial, dental and postcranial morphological characters. The polarity of characters was based on outgroup criteria using the genus Phiomia as the outgroup. All characters are considered to be unordered (34 are binary and nine are multistate). The present analysis leads us to reject the hypothesis that considered Rhynchotherium as a direct ancestor of South American gomphotheres and supports the hypothesis that Sinomastodon is the sister group of Cuvieronius and Stegomastodon. High congruence between the stratigraphical record and the phylogenetic hypothesis is observed. [ABSTRACT FROM AUTHOR]

Aim Our aims were: (1) to characterize the linear relationship between the proportion of woody dicotyledonous species with entire-margined leaves ( E) and mean annual temperature (MAT) from a southern temperate flora that still harbours many lineages that originated under warmer climates; (2) to compare this relationship with those developed from floras of different regions of the world; and (3) to contrast temperature predictions based on leaf margins of the native southern flora versus the naturalized alien flora, mostly of boreal origin. Location The temperate forest of southern South America (TFSA). Methods At each 1° latitudinal band, we estimated E based on species latitudinal ranges and MAT from both an isotherm map and a global temperature grid. We also calculated E from five local floras located between 40 and 43° S, and from the naturalized alien flora of Nahuel Huapi National Park in southern Argentina. Results We found a close relationship between E and MAT for the TFSA. Equations developed from floras of the Northern Hemisphere overestimated extant temperatures of this biome by 6–10 °C at both geographical and local spatial scales. On the other hand, MAT predictions from leaf margins of the alien flora were similar to the actual MAT. A published regression between E and MAT from tropical South America was remarkably similar to the one we estimated from the TFSA. This tropical equation predicted accurately the temperatures observed for this temperate biome based on leaf margins of the native flora. Main conclusions Despite massive plant extinction due to environmental cooling and biogeographical isolation during the Tertiary, leaf-margin analysis reveals that the flora of the TFSA still reflects its original development under the warmer conditions of western Gondwana and its past connections with low-latitude forest floras of tropical South America. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology 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.)

New petrosal bones, assigned to Pucadelphys and Andinodelphys, from the Lower Paleocene of Tiupampa, Bolivia, are described. These remains provide new information on the anatomy of the ear region of these taxa. The re-examination of characters from the petrosal and basicranium shed light on the phylogenetic relationships of the three Tiupampan genera known from complete cranial remains (i.e. Mayulestes, Pucadelphys and Andinodelphys). The combination of dental, general cranial and basicranial characters led to two alternative hypotheses. The first is that borhyaenoids (including Mayulestes) are nested within Notometatheria. Pucadelphyds (i.e. Pucadelphys and Andinodelphys) are the sister group of a clade comprising MHNC 8369 (one isolated petrosal from Tiupampa) and Marsupialia. The second favours the paraphyly of ‘borhyaenoids’ (i.e. the exclusion of Mayulestes from borhyaenoids) and the polyphyly of ‘Notometatheria’. In this case, Mayulestes and borhyaenids represent the stem group of a clade including Asiatic, American and Australian metatherians. This analysis of combined datasets (dental, general cranial and basicranial) highlighted contradictory information in the dental and cranial characters, serving to emphasize that in a large anatomical complex like an entire skull mosaic evolution of the characters is likely. [ABSTRACT FROM AUTHOR]

Predator assemblages are complex systems in which asynchrony in the dynamics of resources and consumers, and the idiosyncratic perception of environmental conditions by the predators may obscure the detection of expected patterns. We disentangle the specific effects of these variables on the guild structure of a vertebrate predatory assemblage in a semiarid ecosystem of western South America. Over 16 years, this system faced dramatic fluctuations in prey availability associated with four El Niño events. After controlling for other sources of variation, we tested if increased resource availability is associated with higher niche overlaps, as expected from the lean/fat scenario. We determined the existence of two trophic guilds of predators (specialized mammal-eaters and omnivorous species with emphasis on arthropods) and found that they responded to increased productivity both at the guild and whole assemblage levels. However, the population response of arthropod prey (almost simultaneous) and of different small mammal prey (delayed by 1 or 2 years) to productivity imposed a degree of asynchrony in prey availability and in the response of predators. This resulted in the between-guilds exchange of predator species depending on mammal prey scarcity or abundance. As a consequence, the observed pattern was an apparent lack of response at the assemblage level. Despite differences in the perception of prey levels by predators, we conclude that each one of them responded accordingly to theoretical predictions following a simple rule: if prey resources are not limiting, predators behave opportunistically converging over the most abundant resources, thus increasing niche overlap; if prey shortages occur, predators specialize on those prey resources that they gather most efficiently, thus lowering niche overlap; if resources become even scarcer, all predators converge again upon the few prey resources still available, thus increasing overlap – out of necessity. [ABSTRACT FROM AUTHOR]

Aim This study analyses long-term responses to climate changes in Podocarpus parlatorei, a cold-tolerant tree species from the subtropics in South America, using distribution patterns of isozyme variation. Location Podocarpus parlatorei characterizes montane forests within the Yungas, a cloud forest of the subtropics of north-western Argentina and southern Bolivia. Podocarpus parlatorei consists of disjunct populations ecologically subdivided into northern, central, and southern sectors that we predict will be genetically divergent from one another as a result of historical isolation. Methods We collected fresh leaves from a maximum of 30 randomly selected individuals from each of 18 populations. We resolved 25 isozyme loci, and scored the most consistent 14, 57% of which were polymorphic. Within-population variation was tested against latitude, longitude, and elevation using multiple regressions. Genetic structure across populations was analysed using diversity parameters. The relationship between genetic and geographic distances was explored with reference to Pearson correlation coefficients. Results The effective number of alleles and observed heterozygosity increase latitudinally. Southern populations tend to be the most variable and genetically distinct. This result suggests that they could represent the location of a long-term refuge for P. parlatorei. The mean number of alleles per locus decreases with elevation. The total genetic diversity is HT = 0.163, 10% of which is distributed among populations. A positive association between genetic and geographic distances was detected. Main conclusions Reductions in genetic diversity towards the north and high-elevation mountains are consistent with evidence of patterns of forest migration resulting from climate change during the Late Quaternary, northern expansion during episodes of cooling, and range contraction towards the highlands during warming trends. Naturally disjunct populations of P. parlatorei are genetically divergent from one another, indicating that local genetic stocks should be used for restoration of degraded habitats. [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.)

To use published distributional and taxonomic information on Neotropical birds in a cladistic analysis of distributions and endemism (CADE) to generate a testable hypothesis of area-relationships for the arid areas of endemism, particularly those of Central South America (the‘arid diagonal’), and to clarify the different methodologies commonly associated with parsimony analysis of endemicity (PAE).South America.Cladistic analysis of distributions and endemism.We obtain a tree where the relationships of most areas are resolved, and we find support for an exclusive clade of Central South American areas, with the Caatinga as sister to both the Chaco and Cerrado.There is a substantial amount of historical signal in avian distributions, when large numbers of taxa and multiple taxonomic levels are considered. Ecological noise and historical information are more easily distinguished in CADE analyses than they would be in PAE analyses. Based on our results we predict that among aridland birds, the Cerrado and Chaco species will be more closely related to each other than to Caatinga species. [ABSTRACT FROM AUTHOR]

Abstract Aim Palaeoenvironmental records of Pleistocene glaciation and associated vegetation changes in Patagonia have led to the hypothesis that during the last glacial maximum (LGM) tree species survived locally in favourable habitats. If present populations originated from spread from only one refugium, such as an ice-free area of coastal Chile (Single Refugium hypothesis), we would expect that eastern populations would be genetically depauperate and highly similar to western populations. In contrast, if the ice cap was not complete and tree species persisted in forest patches on both slopes of the Andes (Multiple Refugia hypothesis), we would expect a greater degree of genetic divergence between populations either on opposite sides of the Cordillera (Cordillera Effect scenario) or towards its present-day southern distributional limit where the ice sheet reached its maximum coverage (Extent-of-the-Ice scenario). Location We tested this refugia hypothesis using patterns of isozyme variation in populations sampled over the entire modern range of the endemic conifer Fitzroya cupressoides (Mol.) Johnst. (Cupressaceae) in temperate South America. Methods Fresh foliage was collected from twenty-four populations and analysed by horizontal electrophoresis on starch gels. Results Twenty-one putative loci were reliably scored and 52% were polymorphic in at least one population. Populations from the eastern slope of the Andes were genetically more variable than those from the western slope; the former had a greater mean number of alleles per locus, a larger total number of alleles and rare alleles, and higher polymorphism. Genetic identities within western populations were greater than within eastern populations. Discriminant analyses using allelic frequencies of different grouping schedules of populations were non significant when testing for the Single Refugium hypothesis whereas significant results were obtained for the Multiple Refugia hypothesis. Main conclusions Our results indicate that present Fitzroya populations are the result of spreading from at least two, but possibly more, glacial refugia located in Coastal Chile and on the southern flanks of the Andes in Argentina. [ABSTRACT FROM AUTHOR]

We analyze the distribution of body masses for 701 species of South American terrestrial mammals at different spatial resolutions from continental to biome, to local habitat scales. Previous studies on North American mammals suggest that body size distributions are highly modal and right skewed at continental scales, but become more uniform as spatial scale decreases. We show, in general, that these patterns also hold for the body size distribution of South American terrestrialmammals. However, we also found some striking differences attributable to the history of this biota and related to the Great American Biotic Interchange (GABI). At continental scales the distribution of body masses for South American mammals is highly right skewed and posseses several modes. One mode corresponds to species derived from North American ancestors, while a second mode, towards larger size, is characteristic of the South American stock. The same pattern is apparent at biome and local habitat scales. We found support for the progressive flattening of the distributions as spatial scale decreases, but they do not become as flat (indistinguishable from log-uniform) as theydo in North America. However, the pattern is stronger for species ofSouth American origin. Our results indicate that there is a strong historical component affecting the macroecological structure of contemporary assemblages at different spatial scales. Body size distributions can provide valuable information on the ways biotas built up. [ABSTRACT FROM AUTHOR]

We analyse the geographical distribution of South American mammalian species using two biogeographic indices: environmental resistance (R50) and anisotropy (A50). R50 quantifies the loss of biotic resemblance occurring from any point in the map to the rest of the continent. A50 quantifies the extent to which the perimeter: area ratio of the geographical ranges of all species whose distributions overlap at any particular location depart from the perimeter: area ratio of a circle. We test for the latitudinal Rapoport effect that predicts an increase in the range-sizes of mammalian species, and hence a decrease in the values of R50, towards the south. We test for the effect of mountains on species’ ranges, given that Janzen's argument that ‘mountain passes are higher in the tropics’ implicitly predicts greater anisotropy in the tropics. Continental spatial patterns of variation in R50 and A50 suggest a biogeographic division of South America consistent with most classical zoogeographical classifications proposed for the continent. Rapid change in mammalian range-sizes and shapes occurs at the limit between the Guayano-Brazilian and Andean-Patagonean subregions. R50 data do not support the latitudinal Rapoport effect: the most widespread species locate in the eastern portions of Brazil, the most restricted ones are in association with the Andes. A50 data support Janzen's prediction: the effect of mountains on species’ distributions is greater in equatorial and central regions of the Andes rather than in the south. R50-and A50-contour maps reveal that, mainly due to the effects of the lie of the land and likely differences in the history of the fauna, the continent has a biogeographic texture which must have major constraints on local ecological patterns and processes. This stresses the importance of considering the role... [ABSTRACT FROM AUTHOR]

The change of circumscription of Jarava (Stipeae) from a morphologically homogeneous section with nine species of the genus Stipa to a heterogeneous genus of ca. 60 species is criticized because of the lack of DNA data to support the change. The modification is considered inconvenient in terms of the ICBN article 14.1 on disadvantageous strict application of priority rules, due to the abundance of Stipa in South American arid regions, a fact which is reflected in the extensive use of the name Slipa by Latinamerican botanists. [ABSTRACT FROM AUTHOR]