29 resultados para ARACHNOIDES-HYPOXANTHUS


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Analyses of spatial relationships and social interactions provide insights into the social structure of animal societies and the ways in which social preferences among and between dyads affect higher order social relationships. In this paper we describe the patterns of spatial associations and social interactions among adult male northern muriquis in order to evaluate the dynamics of their social networks above the dyadic levels. Systematic observations were made on the 17 adult males present in a multi-male/multi-female group from April 2004 through February 2005, and in July 2005. Analyses of their spatial relationships identified two distinct male cliques; some adult males (called "N" males) were more connected to the females and immatures than other adult males ("MU" males), which were more connected to one another. Affiliative interactions were significantly higher among dyads belonging to the same clique than to different cliques. Although frequencies of dyadic agonistic interactions were similarly low among individuals within and between cliques, MU males appeared to be subordinate to N males. Nonetheless, there were no significant differences in the copulation rates estimated for MU males and N males. Mutual benefits of cooperation between MU and N cliques in intergroup encounters might explain their ongoing associations in the same mixed-sex group [Current Zoology 58 (2): 342-352, 2012].

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A distribuição geográfica de um táxon é limitada por aspectos ecológicos e históricos. Muitas atividades humanas têm causado modificações na cobertura vegetal, o que leva à fragmentação e perda do habitat. Isso tem levado à extinção local de populações de várias espécies, alterando sua distribuição geográfica. Entre elas estão as duas espécies do gênero Brachyteles (os muriquis), que são primatas endêmicos de um dos biomas mais afetados por esses processos, a Mata Atlântica. A União Internacional para a Conservação da Natureza (UICN) é uma organização que busca conservar a biodiversidade. Entre outros critérios, utiliza o conhecimento sobre as distribuições geográficas restritas das espécies para classificá-las em categorias de ameaça de extinção, nas chamadas listas vermelhas. Para isso, utiliza parâmetros espaciais, cujos resultados indicam o risco de extinção de determinado táxon em relação à sua distribuição geográfica. Muitas vezes os cálculos desses parâmetros são realizados de maneira subjetiva, de maneira que é importante a busca de métodos que tornem as classificações mais objetivas, precisas e replicáveis. Nesse contexto, o presente trabalho testou diferentes métodos de cálculos de três parâmetros relacionados à distribuição geográfica de B. hypoxanthus e B. arachnoides. Tratam-se de espécies ameaçadas de extinção, com localidades de ocorrência bem conhecidas, que foram profundamente afetadas pela degradação da Mata Atlântica. Assim, podem ser consideradas bons modelos para essas análises. Foi construído um banco de dados de localidades de ocorrência atuais das duas espécies. Por meio de abordagens de Sistemas de Informação Geográfica (SIG), foram estimadas a Extensão de Ocorrência (EOO) através de Mínimo Polígono Convexo e α-hull e Área de Ocupação (AOO) e Subpopulações por meio de métodos de grids, buffers circulares e α-hull, em diferentes escalas espaciais. Os resultados dos cálculos desses parâmetros foram comparados para identificar as abordagens e escalas mais adequadas para a avaliação de risco de extinção. Esses resultados indicam que as listas de localidades e os mapas de distribuição disponibilizados pela UICN precisam ser atualizados. Além disso, sugerem que α-hull é uma abordagem vantajosa para EOO e o método de buffers é mais adequado para os parâmetros de AOO e Subpopulações, quando utiliza escalas espaciais menores. Também foi utilizada a ferramenta GeoCAT, para as duas espécies. Essa ferramenta, por realizar análises de EOO e AOO instantâneas e por seus resultados serem semelhantes aos de outras análises, serve como uma abordagem preliminar de risco de extinção baseado no critério de distribuição geográfica.

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We examined the relationship between food patch size and feeding party size with comparative data from two populations of muriquis (Brachyteles arachnoides) in the 37,797-ha forest at the Parque Estadual de Carlos Botelho (PECB), São Paulo, and the 800-ha forest at the Estacao Biologica de Caratinga (EBC), Minas Gerais. Precipitation Mins more abundant and less seasonal at PECB than EBC, and the density of large trees (>25.0 cm) was higher at PECB (206 ha(-1)) than at EBC (132 ha(-1)). At both sites, the size of feeding parties is positively related to the size of food patches, As predicted, food parches at PECB are significantly larger than those at EBC for both fruit and leaf sources. Contrary to expectations, feeding parties were larger at EEC than PECB, the higher population density of muriquis and sympatric primates at EBC may make large associations more advantageous to these muriquis than to muriquis living at lower population densities in PECB.

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Background An adult male Brachyteles arachanoides, kept in captivity since 1990, was found dead without apparent clinical evidence. Methods Necropsy report, histopathology, immunohistochemistry, and ultrastructural examination were conducted. Results Pulmonary syncytial cells were positive for respiratory syncytial virus (RSV), and ultrastructural examination revealed viral particles inside macrophages compatible with the Paramyxoviridae family. Conclusions Muriquis are susceptible to RSV pneumonia followed by respiratory distress syndrome and death.

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Ocean acidification, as a result of increased atmospheric CO2, has the potential to adversely affect the larval stages of many marine organisms and hence have profound effects on marine ecosystems. This is the first study of its kind to investigate the effects of ocean acidification on the early life-history stages of three echinoderms species, two asteroids and one irregular echinoid. Potential latitudinal variations on the effects of ocean acidification were also investigated by selecting a polar species (Odontaster validus), a temperate species (Patiriella regularis), and a tropical species (Arachnoides placenta). The effects of reduced seawater pH levels on the fertilization of gametes, larval survival and morphometrics on the aforementioned species were evaluated under experimental conditions. The pH levels considered for this research include ambient seawater (pH 8.1 or pH 8.2), levels predicted for 2100 (pH 7.7 and pH 7.6) and the extreme pH of 7.0, adjusted by bubbling CO2 gas into filtered seawater. Fertilization for Odontaster validus and Patiriella regularis for the predicted scenarios for 2100 was robust, whereas fertilization was significantly reduced in Arachnoides placenta. Larval survival was robust for the three species at pH 7.8, but numbers declined when pH dropped below 7.6. Normal A. placenta larvae developed in pH 7.8, whereas smaller larvae were observed for O. validus and P. regularis under the same pH treatment. Seawater pH levels below 7.6 resulted in smaller and underdeveloped larvae for all three species. The greatest effects were expected for the Antarctic asteroid O. validus but overall the tropical sand dollar A. placenta was the most affected by the reduction in seawater pH. The effects of ocean acidification on the asteroids O. validus and P. regulars, and the sand dollar A. placenta are species-specific. Several parameters, such as taxonomic differences, physiology, genetic makeup and the population's evolutionary history may have contributed to this variability. This study highlights the vulnerability of the early developmental stages and the complexity of ocean acidification. However, future research is needed to understand the effects at individual, community and ecosystem levels.

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In order to study the intra- and interspecific variability of the 14/15 association in Platyrrhini, we analyzed 15 species from 13 genera, including species that had not been described yet. The DNA libraries of human chromosomes 14 and 15 were hybridized to metaphases of Alouatta guariba clamitans, A. caraya, A. sara, Ateles paniscus chamek, Lagothrix lagothricha, Brachyteles arachnoides, Saguinus midas midas, Leontopithecus chrysomelas, Callimico goeldii, Callithrix sp., Cebus apella, Aotus nigriceps, Cacajao melanocephalus, Chiropotes satanas and Callicebus caligatus. The 14/15 hybridization pattern was present in 13 species, but not in Alouatta sara that showed a 14/15/14 pattern and Aotus nigriceps that showed a 15/14/15/14 pattern. In the majority of the species, the HSA 14 homologue retained synteny for the entire chromosome, whereas the HSA 15 homologue displayed fragmented segments. Within primates, the New World monkeys represent the taxon with the highest variability in chromosome number (2n = 16 to 62). The presence of the HSA 14/15 association in all species and subspecies studied herein confirms that this association is the ancestral condition for platyrrhines and that this association has been retained in most platyrrhines, despite the occurrence of extensive inter- and intrachromosomal rearrangements in this infraorder of Primates.

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A better understanding of a species` reproductive physiology can help conservation programs to manage primates in the wild and develop assisted reproductive technologies in captivity. We investigated whether measurements of fecal progestin and estrogen metabolites obtained by a radioimmunoassay could be used to monitor the ovarian cycle of Alouatta caraya. We also compared the occurrence of vaginal bleeding with the hormone profiles. We collected fecal samples from 3 adult and 1 subadult captive female over 5 mo and performed vaginal cytology for the adults. The interval between fecal progestin surges in the adult females was 19.11 +/- 2.14 d (n = 18 cycles). Fecal progestin concentrations remained at basal values for 9.83 +/- 2.21 d (n = 18) and rose to elevated values for 9.47 +/- 0.72 d (n = 19). The subadult female showed basal levels of fecal estrogen and progestin concentrations throughout the study, suggesting that our hormone measurements are valid to monitor the ovarian cycle. Bleeding periods coincided with basal levels of fecal estrogens and progestin at intervals of 19.8 +/- 0.9 d and lasted for 4.1 +/- 1.0 d. Although we obtained these data from only 3 individuals, the results indicate that this species likely has a menstrual-type ovarian cycle. These data provide the first endocrine profile for the Alouatta caraya ovarian cycle and are similar to results obtained for other howler species. This similarity is important for comparative studies of howlers, allowing for a better understanding of their reproductive physiology and contributing to a critical information base for managing Alouatta species.

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Human interventions in natural environments are the main cause of biodiversity loss worldwide. The situation is not different in southern Brazil, home of five primate species. Although some earlier studies exist, studies on the primates of this region began to be consistently carried out in the 1980s and have continued since then. In addition to important initiatives to study and protect the highly endangered Leontopithecus caissara Lorrini & Persson, 1990 and Brachyteles arachnoides E. Geoffroy, 1806, other species, including locally threatened ones, have been the focus of research, management, and protection initiatives. Since 1993, the urban monkeys program (PMU, Programa Macacos Urbanos) has surveyed the distribution and assessed threats to populations of Alouatta guariba clamitans (Cabrera, 1940) in Porto Alegre and vicinity. PMU has developed conservation strategies on four fronts: (1) scientific research on biology and ecology, providing basic knowledge to support all other activities of the group; (2) conservation education, which emphasizes educational presentations and long-term projects in schools near howler populations, based on the flagship species approach; (3) management, analyzing conflicts involving howlers and human communities, focusing on mitigating these problems and on appropriate relocation of injured or at-risk individuals; and finally, (4) Public Policies aimed at reducing and/or preventing the impact of urban expansion, contributing to create protected areas and to strengthen environmental laws. These different approaches have contributed to protect howler monkey populations over the short term, indicating that working collectively and acting on diversified and interrelated fronts are essential to achieve conservation goals. The synergistic results of these approaches and their relationship to the prospects for primatology in southern Brazil are presented in this review.

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Pela análise de seis sistemas enzimáticos (ACP, ALP, CAT, GOT, PPO e PO), com 18 locos polimórficos, foram calculadas as freqüências alélicas de 24 alelos referentes a 141 indivíduos adultos de uma população natural de Cryptocarya moschata (noz-moscada-do-Brasil) do Parque Estadual Carlos Botelho (24º03'21" S, 47º59'36" W), São Miguel Arcanjo, SP, amostrados em uma área de cerca de 647 ha. A estrutura genética espacial foi investigada através do método de autocorrelação espacial, utilizando-se coeficientes I de Moran estimados para 10 classes de distância. Adicionalmente, para as mesmas classes de distância, estimaram-se os coeficientes r através de uma análise multivariada. Ambas as abordagens mostraram-se similares qualitativamente, sendo que 15 correlogramas de coeficientes I foram significativos ao nível de 95% de probabilidade. O correlograma total gerado pelos coeficientes r indicou estruturação espacial significativa para a classe de distância de 0 a 150 m. Pela subdivisão desta classe em intervalos de 10 m, detectou-se autocorrelação espacial positiva na maioria das classes, indicando que os agrupamentos de árvores de C. moschata, que se encontram separadas a distâncias menores que 50 m, são constituídos por indivíduos semelhantes geneticamente e provavelmente aparentados. Contudo, a maior similaridade genética ocorreu entre indivíduos distanciados em torno de 105 m, podendo estar associada à dispersão de sementes promovida por Brachyteles arachnoides (Primates - Cebidae). Pela análise dos resultados, conclui-se que para uma amostragem adequada, visando a detecção de diversidade genética, a coleta de indivíduos distanciados acima de 750 m seria recomendável.

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In order to study the intergeneric variability of the Y chromosome, we describe the hybridization of the Y chromosome of Brachyteles arachnoides, obtained by microdissection, to metaphases of Ateles belzebuth marginatus, Lagothrix lagothricha, and Alouatta male specimens. Brachyteles arachnoides (Atelinae) has 62 chromosomes and a very small Y chromosome. Our results showed that the Brachyteles arachnoides Y chromosome probe hybridized to Lagothrix lagothricha metaphases yielding one hybridization signal on only the tiny Y chromosome, and when hybridized with Ateles belzebuth marginatus metaphases it yielded one hybridization signal on two thirds of the small acrocentric Y chromosome. However, no hybridization signal was observed in Alouatta metaphases (subfamily Alouattinae), a closely related genus in the Atelidae family. Furthermore, our data support a close phylogenetic relationship among Brachyteles, Ateles, and Lagothrix and their placement in the Atelinae subfamily, but exclude Alouatta from this group indicating its placement as basal to this group. Copyright (C) 2009 S. Karger AG, Basel

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