Na Capa, Folha de Rosto e Ficha Catalogr?fica constam o t?tulo: "Parti??o de recursos entre duas esp?cies simp?tricas de Gracilinanus (Didelphimorphia: Didelphidae): rela??o com o uso do espa?o e ecologia alimentar". / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-07-03T17:44:50Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) camilla_souza_paula.pdf: 1869121 bytes, checksum: 8447fdb830cc6e38dc596372753d5bb8 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-07-18T12:54:35Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) camilla_souza_paula.pdf: 1869121 bytes, checksum: 8447fdb830cc6e38dc596372753d5bb8 (MD5) / Made available in DSpace on 2018-07-18T12:54:35Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) camilla_souza_paula.pdf: 1869121 bytes, checksum: 8447fdb830cc6e38dc596372753d5bb8 (MD5) Previous issue date: 2017 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Diversas esp?cies de pequenos mam?feros Neotropicais ocorrem em simpatria ao longo de suas ?reas de distribui??o e ? relevante compreender os mecanismos que favorecem a coexist?ncia das esp?cies e que controlam a estrutura da comunidade ecol?gica. O objetivo do presente estudo foi analisar os poss?veis mecanismos de particionamento de recursos entre as esp?cies simp?tricas Gracilinanus agilise G. microtarsus, avaliando o nicho alimentar e o nicho espacial.O estudo foi realizado no per?odo de maio de 2016 a janeiro de 2017 em uma ?rea de mata ciliar sav?nica, no Parque Estadual do Rio Preto, Minas Gerais. Analisamos a dieta das duas esp?cies atrav?s da frequ?ncia de ocorr?ncia dos itens alimentares presentes nas fezes, al?m disso, estudamos o uso do espa?o realizado pelas esp?cies e a rela??o com a heterogeneidade e complexidade ambiental. Analisamos a dieta das duas esp?cies atrav?s da frequ?ncia de ocorr?ncia dos itens alimentares presentes nas fezes. As esp?cies apresentaram uma alta sobreposi??o de nicho no consumo de itens alimentares (CH=0,96), com algumas diferen?as na frequ?ncia de ocorr?ncia dos itens consumidos. Apesar dos itens mais frequentes nas amostras fazer parte da categoria dos invertebrados (Hymenoptera, Isoptera e Coleoptera), a propor??o que esses itens apareceram nas amostras foi diferente para as duas esp?cies, al?m disso, a variedade de itens alimentares tamb?m diferiu entre as esp?cies, onde observamos a presen?a de flores nas amostras de G. agilis, e uma maior variedade de frutos nas amostras de G. microtarsus. Atrav?s das abund?ncias relativas das esp?cies por estrato observamos que ambas utilizam preferencialmente o subbosque, al?m disso, observamos uma segrega??o espacial entre as esp?cies simp?tricas de Gracilinanus, com G. agilis aparentemente ocorrendo mais na borda da mata e, sua cong?nere G. microtarsus, mais no interior da mata. Apesar da alta sobreposi??o de nicho alimentar observada, os resultados indicam que a coexist?ncia das esp?cies simp?tricas estudadas pode estar associada a dois mecanismos: a flexibiliza??o no uso dos itens alimentares e particionamento no uso do espa?o. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biologia Animal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Several species of small Neotropical mammals occur in sympatry throughout their distribution areas and it is relevant to understand the mechanisms that favor the coexistence of the species and that control the structure of the ecological community. The objective of the present study was to analyze the possible mechanisms of partitioning of resources between the sympatric species Gracilinanus agilis and G. microtarsus, evaluating the food niche and the spatial niche. The study was carried out from May 2016 to January 2017 in an area of savanna ciliary forest, in the State Park of Rio Preto, Minas Gerais. We analyzed the diet of the two species through the frequency of occurrence of the food items present in their feces; in addition, we studied the use of the space realized by the species and the relation with the heterogeneity and environmental complexity. The species presented a high niche overlap in the consumption of food items (CH = 0.96), with some differences in the frequency of occurrence of the consumed items. Although the most frequent items in the samples belonged to the category of invertebrates (Hymenoptera, Isoptera and Coleoptera), the proportion that these items appeared in the samples was different for both species. The variety of food items also differed between the species, where the presence of flowers where more observed in the samples of G. agilis, and a greater variety of fruits was observed in the samples of G. microtarsus. The relative abundances of the species per stratum show that both species preferentially use the sub-forest, in addition, we observed a spatial segregation between the sympatric species of Gracilinanus, with G. agilis apparently occurring more at the edge of the forest, and its congener G. microtarsus further into the woods. Despite the high food niche overlap observed, the results indicate that the coexistence of the sympatric species studied may be associated to two mechanisms: flexibility in the use of food items and partitioning in the use of space.

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-07-04T19:40:19Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_cristina_barros_andrade.pdf: 4804696 bytes, checksum: 4747b9532db16586177823f2a1eb0977 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-07-18T13:01:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_cristina_barros_andrade.pdf: 4804696 bytes, checksum: 4747b9532db16586177823f2a1eb0977 (MD5) / Made available in DSpace on 2018-07-18T13:01:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_cristina_barros_andrade.pdf: 4804696 bytes, checksum: 4747b9532db16586177823f2a1eb0977 (MD5) Previous issue date: 2017 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Investigar as rela??es ecol?gicas entre esp?cies simp?tricas e suas intera??es com o habitat, s?o importantes para a compreens?o dos mecanismos que controlam a estrutura da comunidade ecol?gica. Entretanto, informa??es a respeito dos mecanismos que permitam a coexist?ncia entre mam?feros simp?tricos s?o ainda escassas. Descrevemos no presente estudo, os padr?es de dieta dos carn?voros simp?tricos Chironectes minimus e Lontra longicaudis, analisamos os poss?veis mecanismos de particionamento de recursos entre essas esp?cies, a partir das dimens?es de nicho alimentar, temporal e espacial e discutimos o potencial para intera??es interespec?ficas, como a competi??o e preda??o. Os h?bitos alimentares dos carn?voros foram estudados a partir das an?lises de amostras de fezes coletadas entre novembro de 2008 e fevereiro de 2012, em fragmentos de Mata Atl?ntica no arroio Morungava, localizado no munic?pio de Gravata?, Rio Grande do Sul, Brasil. Foram coletadas 85 amostras de C. minimus e 21 amostras de Lontra longicaudis, distribu?das entre 23 latrinas encontradas ao longo das margens direita e esquerda do arroio. A cu?ca d??gua e a lontra neotropical apresentaram h?bitos alimentares especialistas, por?m, com dietas distintas, especialmente com rela??o as preferencias alimentares e ? frequ?ncia dos itens consumidos, o que provavelmente se reflete no baixo ?ndice de sobreposi??o de nicho tr?fico entre as esp?cies. Chironectes minimus apresentou uma dieta primordialmente carnivora, no entanto, bastante diversificada, consumindo principalmente crust?ceos dec?podos (100%), insetos (69%) e peixes (40%), enquanto L. longicaudis apresentou uma dieta baseada principalmente no consumo de peixes (95%), seguidos por insetos (71%), e anf?bios anuros (67%). Observamos um padr?o de segrega??o espacial e temporal entre a cu?ca d??gua e a lontra neotropical na ?rea de estudo, embora, evid?ncias demonstrem que essas esp?cies coexistem em algum momento, tanto no espa?o quanto no tempo, j? que, registramos a preda??o da cu?ca d??gua pela lontra neotropical. Este ? o primeiro estudo de particionamento de recursos entre C. minimus e L. longicaudis, fornecendo informa??es importantes sobre os h?bitos alimentares destes mam?feros semiaqu?ticos e sobre os mecanismos ecol?gicos respons?veis pela estrutura desta guilda de carn?voros na Mata Atl?ntica. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biologia Animal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Investigate the ecological relationships between sympatric species and their interactions with the habitat are important for understanding the mechanisms that control the structure of ecological communities. However, informations regarding the mechanisms that allow the coexistence among sympatric mammals are still scarce. Here we described the feeding habits of two sympatric carnivores, Chironectes minimus and Lontra longicaudis, analyzed the resource partitioning mechanisms investigating different niche dimensions such as feeding, spatial and temporal niches, and also discussed the potential for interspecific interactions, such as intrespecific competition and predation. The feeding habits were studied from the analysis of fecal samples collected between November 2008 and February 2012, in fragments of Atlantic Forest in the Morungava stream, located in the city of Gravata?, Rio Grande do Sul, Brazil. 85 samples of C. minimus and 21 samples of Lontra longicaudis distributed among 23 latrines found along the right and left banks of the stream were collected, Water opossum and Neotropical otter presented specialized food habits, however, with different diets, especially regarding food preferences and frequency of consumed items, which is probably reflected by the slight trophic niche overlap between species. Chironectes minimus presented a primordial carnivorous diet, however, very diversified, consuming decapod crustaceans (100%), insects (69%) and fishes (40%), while L. longicaudis presented a diet based mainly on fish consumption 95%), followed by insects (71%), and anuran amphibians (67%). We observed a spatial and temporal segregation pattern among the water opossum and the Neotropical otter in the study site, although, evidences show that these species coexist at some time, both in space and time, since we recorded the predation of the water opossum by the Neotropical otter. This is the first study of resource partitioning among C. minimus and L. longicaudis, providing significant information about the feeding habits of these semi-aquatic mammals and about the ecological mechanisms responsible for the structure of this carnivorous guild in Atlantic Forest.

Breeding compexes of poeciliid fishes with a bisexual and two unisexual species were studied for mechanisms permitting Sympatric coexistence. The unisexuals are gynogenetic and thereby sexually dependent on the males of the bisexual species for sperm to initiate development, but inheritance is entirely maternal. Bisexual females are more abundant in headwater localities; unisexuals increase in downstream localities. Males were 10 - 18% of the total poeciliid population, regardless of the relative proportions of bisexual to unisexual females. Downstream localities were typified by greater habitat diversity, including a variety of backwater pools. The unisexuals showed a marked preference for such pools. Both field and laboratory studies showed that all three types of females as well as males preferred shaded areas with a gravel substrate. Although the four types of fish were found together, nearest neighbour data indicated that each type of female preferred its own kind. Males courted throughout the year and were indiscriminate in their choice of mates. Despite the skewed sex ratio, males were not in short supply because only a few females were sexually receptive at a given time. No significant differences existed between bisexuals and unisexuals in their relative reproductive outputs, but they were asynchronous.