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This is a brief overview of the career of the Canadian-born, American abstract expressionist painter Philip Guston. The discussion begins by contextualizing Guston's work within the era in art history in which he painted, with particular attention given to issues pertaining to the Cold War. Guston began as a social realist but gradually evolved into an abstract artist, a development which the article carefully tracks. Guston is presented as an artist who was particularly touched by the times in which he lived, as his work was informed by domestic & international issues as diverse as the rise of the Ku Klux Klan, the Great Depression, the Spanish Civil War, the Second World War, & the Vietnam War. The discussion concludes with a summation of Guston's universal tragic sense. R. Young

In the northeastern part of Brazil, located 90% within the semi-arid region of the country, we can find areas that present quite peculiar characteristics, amongst these the Caatinga. This biome is characterized by the floristic composition formed of dry forest and in this semi-arid environment there is an increase in the supply of resources during the rainy season. This is a region lacking in research, particularly in the State of Paraíba, where no survey studies of social wasp were carried out yet. Social wasps are an important predator of plagues species. The objective of this study was to conduct a survey of the community of social wasps (Polistinae species) that inhabit in the neotropical dry forest of Paraiba, in the municipalities of Sumé and Prata, and to compare the richness and abundance of wasps located in areas of Caatinga with those inhabiting areas intercropping plantation with organic farming. The present study sampled 10 Polistinae species distributed in six genera. Two new species were registered for the state. The comparison between the community of social wasps of the Caatinga There was not statistical difference in the richness and abundance between the natural vegetation and organic intercropping. This means that agroecosystem attracted community of Polistinae, promoting the maintenance of social wasps in anthropic environmental and favoring the biological control.

For the first time the association between Partamona seridoensis and Constrictotermes cyphergaster is described. Partamona seridoensis occurs in xeric areas of Northeastern Brazil, and it is a termitophile species as its nests are built in active and inactive arboreal termite nests of the species C. cyphergaster. This study aimed to verify the characteristics of the nesting substrate used by P. seridoensis in two areas of dry forest (caatinga) in Cariri region, Paraíba state. It has been found that the vertical distribution of termites that contained colonies of P. seridoensis varied from 10 cm to 3.60 m, while the height of the nest entrance varied from 20 cm to 3.70 m. Commiphora leptophloeos, popularly known as imburana, was the support tree of 22 (43.1%) from 51 observed termite nests that harbored bee colonies. Most (44; 86.2%) of the host termites colonies were active. Most of the colonies showed the nest entrances not directed to the east/southeast. All colonies located were housed in large termite nests, whose volumes exceed 30 liters. In the two areas surveyed, frequently the entrances of the nests were directed to other nearby colonies, suggesting a parental relationship that should be further investigated.

Due to deforestation and fragmentation of ecosystems, the management of bee populations targeting pollination services is increasingly urgent. Because urban environments are stressful, the dietary knowledge in such areas can help to cope with this issue in the near future. Using palynological analysis the floral resources used by Centris flavifrons, an important pollinator of crops and native plants was studied in an urban area. Byrsonima sericea type, Solanum paniculatum type, Cestrum type, and Myrcia type 1 together accounted for more than 93% of pollen grains foraged by females. It is noteworthy that this bee population depends on few plant species both for pollen and for oil. Furthermore, females showed flexibility to replace the primary pollen source in different breeding seasons, as well as one female could provision different cells in the same nest with different predominant pollen types. It is highlighted the importance of wastelands for keeping bee populations in urban areas.

The conservation of the fauna of bees inhabiting the Brazilian savanna is threatened due to changes in land use in the last decades. We investigated the composition, species richness and abundance of a bee assemblage in the vicinity of the Chapada Diamantina National Park. In addition, we compiled data on composition and diversity from another bee assemblage located in the same portion of the Cerrado, which was previously investigated by one of us almost 30 years ago, in order to produce a more complete panorama on beta diversity of bees in this region. We used a non-metric multidimensional scaling ordination analysis (NMDS) to compare composition of bee assemblages from diff erent types of open vegetation. We recorded 77 bee species (H' = 2.95; J = 0.68), 42% of them were singletons. We collected slightly more than half of the species and 60% of the genera recorded in the bee assemblage studied three decades ago. H' was signifi cantly lower in our area than in the previous study (t = 8.588, p <0.001), but equitability (J) was very similar. Several factors may contribute to these diff erences, including local diff erences in bee assemblage composition, diff erences in the probability of capturing the diff erent species (many rare species), factors affecting the sampling itself, and perhaps species loss over the three decades separating the two studies. The magnitude of species loss is difficult to assess because the two studies were not carried out exactly in the same area and there were differences in sampling time and sampling effort.

In this study we investigated the group of floral resources that support bee populations from a bee assemblage in a savanna, and the way in which bee species use these food resources, with an emphasis on the breadth and overlap of trophic niches. The interactions between 75 species of bees and 62 species of plants visited to obtain floral resources were recorded on a Brazilian savanna site. The bee species explored a diverse set of plant species, but concentrated the collection of resources in a few plant species. The distribution of the samples over a long period favored a robust characterization of the food niche of the bee populations. Byrsonima sericea, Serjania faveolata, and Stigmaphyllon paralias were the plant species with the highest number of links with bees. In general, the trophic niche overlap was low, with 75% of pairs of bee species having a niche overlap (NO) less than 0.33. Only four pairs showed high overlap (NO>0.70) and all cases were related to the exploitation of floral resources provided by B. sericea, a key resource for the maintenance of the local bee fauna, an oil and pollen provider.