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The aim of the study was to analyze the preferences of ant species visiting the trunks of eight species of Magnoliophyta, belonging to the families Fabaceae, Arecaceae, Myrtaceae, Melastomataceae and Euphorbiaceae, located in a fragment of the Atlantic Forest in southeastern Brazil. A total of 101 ant species, belonging to eight subfamilies and 32 genera, were sampled during the 12-month collection period. Close to 30% of the ant species can be considered arboreal, and the others are species that nest in the ground and use trees only for foraging, which can be occasional, as in the case of the Ecitoninae sampled in Arecaceae and Euphorbiaceae. Pachycondyla mesonotalis was the only species collected on all the Magnoliophyta, whereas Camponotus rufipes, Acromyrmex niger and Crematogaster spp., were found on 87.5% of the trees analyzed. No strong similarities were found, using the Jaccard Index, among plant species in the same family of Magnoliophyta based on the visiting ants, except for the Euphorbiaceae species. This result is probably related to the presence of extra-floral nectar, which is very attractive to ants and characteristic of this family.

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The Nile tilapia fish (Oreochromis niloticus) has a high potential to be used as a model in neuroscience studies. In the present study, the preference of the Nile tilapia between a gravel-enriched (GEE), a shelter-enriched (SEE) or a non-enriched (NEE) environment was determined, for developing a place preference model. Nile tilapia had an initial preference for GEE, but after 1 day of observation, the fish stabilized their frequency of visits among compartments. Hence, any stimulus motivating tilapia increase in compartment visiting indicates a positively reinforcing effect. This feature is very useful for the development of new behavioural paradigms for fish in tests using environmental discrimination, such as the conditioning place preference test. © 2006 Elsevier GmbH. All rights reserved.

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Ornithochorous fruits make up an important part of the diet of birds and many studies have related the different morphological types of fruits with the choice by birds. We analyzed the intrinsic characteristics of plants and how human impact can affect this choice. Through analyses of covariance we related the degree of human pressure in each study site (high or low) and the morphological characteristics of 57 ornithochorous species with visiting rates and consumption of fruits by birds. We did not find any intrinsic plant characteristic (life form, size and type of diaspore) that explains the rates of consumption and visit by birds. On the other hand, the degree of human impact affected directly the mutualism between plants and birds. Plant species located in areas that suffer high human pressure had number of visits and consumption rates 3,3 and 3,5 lower than plants located in pristine areas, respectively. The negative consequences of the reduction of consumption of fruits in areas with high human pressures may directly affects the interactions between birds and plants and the regeneration of the ornithochorous species.

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Six microsatellite loci were used to quantify the mating system of two small fragmented populations (Selviria - SEL and Aparecida do Tabuado - APT, Mato Grosso do Sul State) and isolated trees in pastures, of the bat-pollinated tropical tree Hymenaea stignocarpa, growing in the Center-west region of Brazil. In SEL population, seeds were collected from 11 mother-trees; in APT, from three trees and, in the case of isolated trees, from six individuals growing at least 500 m apart in pastures. To investigate if there are differences on mating system between trees in populations and isolated trees, trees from populations were pooled as a group and, likewise, the isolated trees were pooled to another group. The outcrossing rate was higher in the populations (t̂ m= 0.873) than in isolated trees (t̂ m=0.857), but the difference was not significant. Significant and high differences between multi-locus and single-locus outcrossing rate were detected in populations (t̂ m- t̂ s=0.301, P<0.05) and isolated trees (t̂ m- t̂ s=0.276, P<0.05), suggesting mating between relatives. Higher paternity correlation was observed in trees from population (r̂ p=0.636) than in isolated trees (r̂ p=0.377), indicating the occurrence of some correlated matings and that part of offspring are full-sibs. It was not observed increased in self-fertilization rate in isolated trees in pastures. In general terms, the unique observed difference in mating system between populations and isolate trees was the high rate of correlated matings in trees from populations, due probably to the small distance among coespecifics and the pollinator behavior, visiting near trees.

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This study was performed in the southern and southeastern regions of Brazil, visiting numerous municipalities, over a period of 25 years, excavating nests of 12 species of leaf-cutting ants of the Acromyrmex genus. Larvae and pupae of Microdon tigrinus were found only in nests of the leaf-cutting ant Acromyrmex coronatus, indicating high specificity. Observation showed that larvae and pupae were well accepted in the nests and the adults, immediately after puparia eclosion and prior to wing distension, were not attacked by the workers, suggesting that they produce semiochemicals for a short time period until they arrive outside the Acromyrmex coronatus nest. It was postulated that these larvae feed on the organic detritus of the nest, as shown for Microdon larvae of other species.

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The aim of this research was to identify the insects visiting flowers of sweet pepper and evaluate the effects of entomophilous pollination as a whole and, more especifically, of honeybees as pollinators of this crop. This study was carried out in the municipality of Taubaté, State of São Paulo, Brazil (21°01'S; 45°29'W; altitude: 570 m) from April to September, 2002. Insects were collected in thirty-six plants during 10 minutes/hour between 6:00 and 17:00h during days of maximum blooming. Twelve plots were subjected to the following treatments: (1) open-pollinated plots, freely visited by insects; (2) caged plots; (3) caged plots containing a hive of honeybees. Twelve species of insects visited the flowers. Exomalopsis spp. (Hymenoptera, Apidae) were the commonest ones (53,9% of visits). Fruits yielded in treatments (1) and (3) were heavier, presented higher diameter, thicker pericarp and more seeds per fruit than fruits in treatment (2). Results showed that fruits from insect pollinated plots presented better quality. Honeybeesas as pollinators were efficient as the other insects. sweet pepper, Capsicum annuum L., Solanaceae, pollination, Apis mellifera, honeybee.

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Malvaceae shows a rich morphological diversity of secretory structures, which are of great ecological and taxonomical relevance. Nonetheless, until the present moment, studies on the secretory structures of the studied species were not found. Pavonia alnifolia A.St.-Hil. is endangered species of extinction with restricted distribution within the restingas of Rio the Janeiro and Espírito Santo, Brazil. The species were collected from the former and usual techniques on plant anatomy and histochemistry were performed. Anatomical and histochemical studies of the secretory structures of Pavonia alnifolia are showed in this work. The presence of external and internal secretory structures of mucilage in many organs, idioblasts of phenolic and lipid substances and floral nectaries what is a very important adaptative survival mechanism of the species in the restinga environment. The secretion produced by nectaries is envolved with maintenance of interations with visiting insects, what constitutes a good model to experimental studies with an ecological approach.

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The Iguape and Cananéia Lagoon-Estuarine Complex is a biodiversity hotspot in southeastern Brazil. In recent decades, the region has become an important destination for recreational fishing. The objective of this study was to analyze the socioeconomic characteristics of visiting anglers and fishing guides working in the Cananéia-Iguape-Peruíbe Environmental Protected Area and their views on fisheries management. Data were collected through semi-structured interviews conducted between January 2009 and January 2010. We interviewed 278 anglers, who were predominantly male (93%) with a mean age of 47 years and from the state of São Paulo. The targeted species were snooks (Centropomus undecimales and Centropomus parallelus) and weakfishes (Cynoscion leiarchus and Cynoscion acoupa). Only half the anglers had the mandatory fishing license, and many of them lacked knowledge about catch quotas and minimum size requirements for specific species. The fishing guides (n = 80) were all male, with a mean age of 39 years and extensive experience. Most of the guides believe that the study area is somewhat degraded due to the removal of riparian vegetation, siltation, pollution, and especially the depletion of fish stocks. The opinions of the stakeholders (anglers and guides) converge on the high priority needs of the fishery and possible management actions regarding recreational fishing, such as improved fisheries enforcement (first in order of importance), proper training of fishing guides, zoning of fishing areas, and the definition of a maximum size limit. © 2013 Elsevier Ltd.

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The objective of this work was to determine the behavioral differences among laying hens reared at different densities and group sizes, in an enriched environment. Isa Brownlaying hens with ages from 30 to 32-week-old, in small-sized and deformed pens, were used. Hens were raised during 28 days in bays with shavings bedding, perch and nest. Two group sizes were evaluated (6 and 12 fowls) and at two rearing densities (774 and 1,440 cm2 by fowl) in a factorial arrangement with three replicates. In fifteen-minute video footages, it was recorded the frequency and the expression period for the following behavior were recorded: feather scratching, sand bath, wing beating, drinking water, pecking, head scratching, earth scratching, eating, perching, leg stretching, pursuing, sitting, and nest visiting. The treatments and the interaction between them had significant effects. The six-hen group increased the frequency of behavior types that indicate fowl frustration, regardless of density. The group size is the most important factor for hen well-being.

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Pós-graduação em Artes - IA

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)