892 resultados para Bird banding


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Fire management ran increase the biomass of some plant species at fire breaks in reserves of the Cerrado. For example, numerous and large patches of monkey-nuts (Anacardium humile, Anacardiaceae) provide abundant food resources for wildlife in the lower strata of savanna woodlands managed by fire. The objective of this study was to examine the exploitation of A. humile patches by birds in managed savanna woodlands (fire breaks) at Emas National Park, southwest Brazil. The relationship between flock size and the size of Anacardium patches were also investigated. Fire breaks were sampled in September and October 2006, when fruits and flowers were abundant. Ara ararauna was often recorded exploiting resources of Anacardium patches. This species and other psittacids (Amazona aestiva, Alipiopsittaca xanthops, and Diopsittaca nobilis) consumed seeds usually on the ground around fruiting patches. Members of Aratinga aurea flocks and Ramphastos toco consumed pseudo-fruits. Larger flocks detected were those of A. aurea and A. ararauna. Groups of A. ararauna that exploited larger patches tended to be larger than flocks that exploited smaller patches. This study suggests that intra- and interspecific interactions and characteristics of Anacardium patches and of the surrounding vegetation are involved in the feeding ecology of birds in the lower stratum of managed woodlands. Fruiting Anacardium patches attract numerous frugivorous birds to fire breaks at Emas National Park. Further research is needed to a better understanding of the influence of fire management on birds in the Cerrado. Accepted 31 July 2009.

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Aim Habitat loss and climate change are two major drivers of biological diversity. Here we quantify how deforestation has already changed, and how future climate scenarios may change, environmental conditions within the highly disturbed Atlantic forests of Brazil. We also examine how environmental conditions have been altered within the range of selected bird species. Location Atlantic forests of south-eastern Brazil. Methods The historical distribution of 21 bird species was estimated using Maxent. After superimposing the present-day forest cover, we examined the environmental niches hypothesized to be occupied by these birds pre- and post-deforestation using environmental niche factor analysis (ENFA). ENFA was also used to compare conditions in the entire Atlantic forest ecosystem pre- and post-deforestation. The relative influence of land use and climate change on environmental conditions was examined using analysis of similarity and principal components analysis. Results Deforestation in the region has resulted in a decrease in suitable habitat of between 78% and 93% for the Atlantic forest birds included here. Further, Atlantic forest birds today experience generally wetter and less seasonal forest environments than they did historically. Models of future environmental conditions within forest remnants suggest generally warmer conditions and lower annual variation in rainfall due to greater precipitation in the driest quarter of the year. We found that deforestation resulted in a greater divergence of environmental conditions within Atlantic forests than that predicted by climate change. Main conclusions The changes in environmental conditions that have occurred with large-scale deforestation suggest that selective regimes may have shifted and, as a consequence, spatial patterns of intra-specific variation in morphology, behaviour and genes have probably been altered. Although the observed shifts in available environmental conditions resulting from deforestation are greater than those predicted by climate change, the latter will result in novel environments that exceed temperatures in any present-day climates and may lead to biotic attrition unless organisms can adapt to these warmer conditions. Conserving intra-specific diversity over the long term will require considering both how changes in the recent past have influenced contemporary populations and the impact of future environmental change.

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The Russian senior seminar this semester focused on Bulgakov’s famous novel, Master and Margarita. This presentation focuses on one of the themes of the novel, specifically Bulgakov’s use of birds in his work. Birds appear numerous times in Master and Margarita, and it always has a connotation of either a lack of freedom or a recent achievement of this goal. There are even instances in which characters themselves, as they seek freedom from their former oppressive lives, become the “birds” in the novel. This paper is an exploration of bird imagery in the novel.

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

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A satellite DNA sequence of Parodon hilarii ( named pPh2004) was isolated, cloned and sequenced. This satellite DNA is composed of 200 bp, 60% AT rich. In situ hybridization ( FISH) results revealed that the satellite DNA pPh2004 is located in the terminal regions of several chromosomes, forming highly evident blocks in some and punctual marks in others. The comparison between the FISH and C-banding results showed that the location of this satellite DNA coincides with that of most terminal heterochromatins. However, some regions are only marked by FISH whereas other regions are only marked by C-banding. The possible existence of more than one satellite DNA family could explain these partial differences. The in situ hybridization with the satellite DNA and the G- and C-bandings confirmed the presence of a sex chromosome system of the ZZ/ZW type in P. hilarii, as well as the correct identification of the Z chromosome in the karyotype. This chromosome displays a segment of terminal heterochromatin in the long arm, similar to the segment observed in the short arm of the W chromosome, also showing a G- banding pattern similar to that of the short arm and part of the long arm of the W chromosome. A hypothesis on the origin of the W chromosome from an ancestral chromosome similar to the Z chromosome is presented.

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Two wild diploid (2n = 20 chromosomes) and self-pollinating Arachis species, Arachis Pintoi Krapov and W.C.Gregory and A. villosulicarpa Hoehne were submmited to C-band technique to karyotype analyses. Root tips were employed in the analyses. Morphometric data chose that chromosome lengths varied from 3.12 in A. villosulicarpa to 1.45 in A. Pintoi. Karyotype formula obtained was 10sm to A. Pintoi and 9sm + 1m to A. villosulicarpa. There was a predominance of pericentromeric C-band in all mitotic metaphasic chromosomes in both species. Besides C-band values, both species still did not differ in respect to chromosome absolute and relative lengths, centromeric index, symmetry index and total karyotype haploid length. C-band and morphometric data did not show strong or significant differences which could separate these two species of peanut which belong to evolutive different sections.

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Achiridae is an important family of the order Pleuronectiformes widely distributed in North, Central, and South America with freshwater and marine species. In the present study cytogenetic analyses comprising conventional and molecular techniques were carried out in seven species of this family. The following diploid numbers (2n) and fundamental numbers (FN) were obtained: Achirus declivis 2n = 34, FN = 52; Achirus lineatus 2n = 40, FN = 66; Catathyridium jenynsi 2n = 40 and FN = 50; Gymnachirus nudus 2n = 36 and FN = 50; Hypoclinemus mentalis 2n = 38 and FN = 54; Trinectes paulistanus 2n = 42 and FN = 52; and Trinectes sp. 2n = 38 and FN = 54. All species presented a single nucleolar organizer region (NOR) bearing chromosome pair and C-band positive segments mainly distributed at the pericentromeric position. The wide variation observed in chromosome number and FN suggests the occurrence of larger chromosome rearrangements in the family Achiridae if compared with other families of the same order.

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Different cytogenetic techniques were used to analyse the chromosomes of Prochilodus lineatus with the main objective of comparing the base composition of A- and B-chromosomes. The results of digestion of chromosomes with 10 different restriction endonucleases (REs), silver staining, CMA(3) staining and C-banding indicated the existence of different classes of highly repetitive DNA in the A-set and also suggested the existence of compositional differences between the chromatin of A- and B-chromosomes. The 5-BrdU incorporation technique showed a late replicating pattern in all B-chromosomes and in some heterochromatic pericentromeric regions of A-chromosomes. The cleavage with RE BamHI produced a band pattern in all chromosomes of P. lineatus which permitted the tentative pairing of homologues in the karyotype of this species. We concluded that the combined use of the above techniques can contribute to the correct identification of chromosomes and the karyotypic analysis in fishes. on the basis of the results, some aspects of chromosome structure and the origin of the B-chromosomes in P. lineatus are discussed.

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It is crucial for biodiversity conservation that protected areas are large and effective enough to support viable populations of their original species. We used a point count distance sampling method to estimate population sizes of a range of bird species in three Atlantic forest protected areas of size 5600, 22,500, and 46,050 ha. Population sizes were generally related to reserve area, although in the mid-sized reserve, there were many rare species reflecting a high degree of habitat heterogeneity. The proportions of forest species having estimated populations > 500 ranged from 55% of 210 species in the largest reserve to just 25% of 140 species in the smallest reserve. All forest species in the largest reserves had expected populations > 100, but in the small reserve, 28% (38 species) had populations < 100 individuals. Atlantic forest endemics were no more or less likely to have small populations than widespread species. There are 79 reserves (> 1000 ha) in the Atlantic forest lowlands. However, all but three reserves in the north of the region (Espirito Santo and states north) are smaller than 10,000 ha, and we predict serious levels of local extinction from these reserves. Habitat heterogeneity within reserves may promote species richness within them, but it may also be important in determining species loss over time by suppressing populations of individual species. We suggest that most reserves in the region are so small that homogeneity in the habitat/altitude within them is beneficial for maintenance of their (comparatively small) original species compliment. A lack of protection in the north, continued detrimental human activity inside reserves, and our poor knowledge of how well the reserve system protects individual taxa, are crucial considerations in biodiversity management in the region.

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Cytogenetic investigations based on conventional and differential staining analysis (C-and replication R-banding and Ag-staining) were carried out on eight specimens of Phyllopezus periosus, 17 of P. pollicaris pollicaris, and one of P. pollicaris przewalskii collected from different localities of Brazil. P. periosus and P. p. pollicaris share the same diploid number of 2n = 40 chromosomes, and their karyotypes are very distinctive regarding to the number of biarmed and uniarmed chromosomes. After careful side-by-side comparison of R-banded chromosomes in both taxa, pronounced homology between, at least, eight pairs was revealed. The R-banding patterns allowed us to postulate that karyotype differentiation could be due to pericentric inversion events. P. p. przewalskii (2n = 38) exhibited a very similar karyotype to that found in P. p. pollicaris, except for the presence of one metacentric pair, which probably resulted from a Robertsonian rearrangement. Single and multiple pairs of NOR-bearing chromosomes, showing variation in number and location, were detected among the three forms of Phyllopezus. Similar C-banding patterns were found in P. periosus and P. p. pollicaris. Sex chromosomes were not positively identified.

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