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A ecomorfologia apresenta diferentes ramos, sendo a ecomorfologia comparada o ramo proposto neste trabalho, qual segue a análise das estruturas convergentes dos representantes das famílias africana Pantodontidae e neotropical Gasteropelecidae. Para tal, são analisadas e discutidas as pressões seletivas exercidas pelos ambientes muito similares encontrados nos pequenos córregos e igarapés localizados no interior da Floresta do Congo e Floresta Amazônica, onde vivem respectivamente as espécies africanas e neotropicais. Assim, foi possível identificar uma forte convergência adaptativa na musculatura das nadadeiras peitorais, uma vez que são adaptações aos saltos de longo alcance para fora dágua, característicos de todas as espécies analisadas, tratadas em conjunto por peixes-borboleta de água doce (Weist, 1995; Saidel et al., 2003). / The ecomorphology studies present different fields. The Comparative Ecomorphology, the field suggested at this work, follows the analyses of convergent structures found among Pantodontidae african families and Gasteropelecidae neotropical families. Due to that, we evaluated the selective pressures from similar aquatic environments, such as streams and small rivers. The analyses of african and neotropical species were done in relation to the Congo and Amazon Forest areas, respectively. In this context, we identified strong adaptive convergence in the musculature associated to the pectoral fins. These adaptations are related, in both studied cases, to the ability to jump long distandes out of the water (Weist, 1995; Saidel et al., 2003).

Resource variation and species interactions require organisms to respond behaviorally, physiologically, and morphologically within and among generations to compensate for spatial and temporal environmental variation. One successful evolutionary strategy to mitigate environmental variation is phenotypic plasticity: the production of alternative phenotypes in response to environmental variation. Phenotypic plasticity yields multiple characters that may enable organisms to better optimize phenotypic responses across environmental gradients. In this thesis, I trace the development of thought on phenotypic plasticity and present two empirical studies that implicate phenotypic plasticity in producing morphological variation in response to resource variation. The first empirical study addresses trophic plasticity, population divergence, and the effect of fine-scale environmental variation in western mosquitofish (Gambusia affinis). Offspring from two populations were fed either attached or unattached food items offered in three orientations: (1) water surface, (2) mid-water, (3) benthic, and (4) a daily rotation of the former three (fine-grained variation). Attached food induced wide heads, blunt snouts and rounded pectoral fins relative to morphology in the unattached treatment. Mid-water feeding induced elongated heads and deeper mid-bodies relative to benthic and surface feeding induced morphologies. The rotating treatment produced intermediate morphologies. Population divergence seemed related to both trophic and predation ecology. Ecomorphological consequences of induced morphologies and the need for inclusion of greater ecological complexity in studies of plasticity are discussed. The second study examines induced morphological plasticity and performance in red drum (Sciaenops ocellatus). I fed hatchery fish either hard or soft food for two months. Performance trials were designed to measure their ability to manipulate and consume hard food items. External morphology and the mass of pharyngeal crushing muscles were assessed for variation among treatments. A hard food diet induced deeper bodies and larger heads, more massive pharyngeal muscles, and initially more efficient consumption of hard food than fish receiving soft food. The observed morphological variation is in accordance with variation among species. Determining evolutionary mechanisms operating within red drum populations should eventually aid in developing and optimizing conservation efforts and ease the transition from hatchery facilities to estuaries.

Resource variation and species interactions require organisms to respond behaviorally, physiologically, and morphologically within and among generations to compensate for spatial and temporal environmental variation. One successful evolutionary strategy to mitigate environmental variation is phenotypic plasticity: the production of alternative phenotypes in response to environmental variation. Phenotypic plasticity yields multiple characters that may enable organisms to better optimize phenotypic responses across environmental gradients. In this thesis, I trace the development of thought on phenotypic plasticity and present two empirical studies that implicate phenotypic plasticity in producing morphological variation in response to resource variation. The first empirical study addresses trophic plasticity, population divergence, and the effect of fine-scale environmental variation in western mosquitofish (Gambusia affinis). Offspring from two populations were fed either attached or unattached food items offered in three orientations: (1) water surface, (2) mid-water, (3) benthic, and (4) a daily rotation of the former three (fine-grained variation). Attached food induced wide heads, blunt snouts and rounded pectoral fins relative to morphology in the unattached treatment. Mid-water feeding induced elongated heads and deeper mid-bodies relative to benthic and surface feeding induced morphologies. The rotating treatment produced intermediate morphologies. Population divergence seemed related to both trophic and predation ecology. Ecomorphological consequences of induced morphologies and the need for inclusion of greater ecological complexity in studies of plasticity are discussed. The second study examines induced morphological plasticity and performance in red drum (Sciaenops ocellatus). I fed hatchery fish either hard or soft food for two months. Performance trials were designed to measure their ability to manipulate and consume hard food items. External morphology and the mass of pharyngeal crushing muscles were assessed for variation among treatments. A hard food diet induced deeper bodies and larger heads, more massive pharyngeal muscles, and initially more efficient consumption of hard food than fish receiving soft food. The observed morphological variation is in accordance with variation among species. Determining evolutionary mechanisms operating within red drum populations should eventually aid in developing and optimizing conservation efforts and ease the transition from hatchery facilities to estuaries.

Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-25Bitstream added on 2014-06-13T20:00:46Z : No. of bitstreams: 1 lopez_cm_dr_jabo.pdf: 22316757 bytes, checksum: f48afacc1bb98b5495a7a02038c3042b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O principal objetivo deste trabalho foi caracterizar a vereda Curral das Éguas, por meio da investigação de seus recursos naturais, o qual integra um conjunto de indicadores limnológicos e ecomorfológicos. A vereda está inserida na cabeceira de um afluente da bacia do rio São Francisco, situada na região de Três Marias/MG. As amostragens foram realizadas em cinco períodos representativos do ciclo hidrológico. Os recursos disponíveis nos habitats foram observados em quatro trechos selecionados com base nas diferenciações das zonas funcionais do sistema, ao longo do gradiente longitudinal da vereda. O protocolo de avaliação foi aplicado com o intuito de quantificar os atributos ecofísicos do leito, das margens e do ambiente no entorno. Os aspectos limnológicos foram pesquisados de forma concomitante por intermédio das variáveis físicas, químicas e biológicas das águas. As principais fontes de carbono orgânico foram estudadas por intermédio do potencial de lixiviação das macrófitas dominantes e das frações foliares de Mauritia flexuosa (buriti), sendo o aporte de carbono orgânico dissolvido mapeado nos trechos de amostragem. A composição, riqueza e abundância das comunidades de microinvertebrados fitófilos (Protista, Rotifera e Crustacea) foram pesquisadas e a distribuição espaço temporal dos organismos zooperifíticos descrita numa abordagem interativa com as variáveis limnológicas e ecofísicas da vereda / The main purpose of this work was to characterize the vereda Curral das Éguas in its state of conservation, by means of inquiring its natural resources, which integrate a set of limnological and ecomorfological indicators. This vereda is inserted in the headspring affluent of the São Francisco river basin, localized in the region of Três Marias, Minas Gerais State. For that intention were selected four stretches, based in the different functional zones, through the longitudinal gradient of vereda system. The samplings were collected in five representative periods of hidrological cycle, based on resource available in the habitat. The evaluation protocol was applied to semiquantify the physical attributes, and assess habitat quality of the stream bed, margins and surrounding environment. The limnological aspects had been searched through the physical, chemical and biological variables of the water. The principal sources of organic carbon had been studied by means leaching potential of the dominant macrophytes and buritis (Mauritia flexuosa) fractions of the leaves. The contributions of organic carbon dissolved were mapped in the sampling stretches. The composition, richness and abundance of microinvertebrates phytophylous community (Protista, Rotifera and Crustacea) were searched, and the spatial temporal distribution of the organisms, described in a interative abordation with the ecophysical and liminological variables

Orientador: Antonio Fernando Monteiro Camargo / Banca: Maria Letizia Petesse / Banca: Wagner Cotroni Valenti / Banca: Irineu Bianchini Junior / Banca: Marcela Bianchessi da Cunha Santino / Resumo: O principal objetivo deste trabalho foi caracterizar a vereda Curral das Éguas, por meio da investigação de seus recursos naturais, o qual integra um conjunto de indicadores limnológicos e ecomorfológicos. A vereda está inserida na cabeceira de um afluente da bacia do rio São Francisco, situada na região de Três Marias/MG. As amostragens foram realizadas em cinco períodos representativos do ciclo hidrológico. Os recursos disponíveis nos habitats foram observados em quatro trechos selecionados com base nas diferenciações das zonas funcionais do sistema, ao longo do gradiente longitudinal da vereda. O protocolo de avaliação foi aplicado com o intuito de quantificar os atributos ecofísicos do leito, das margens e do ambiente no entorno. Os aspectos limnológicos foram pesquisados de forma concomitante por intermédio das variáveis físicas, químicas e biológicas das águas. As principais fontes de carbono orgânico foram estudadas por intermédio do potencial de lixiviação das macrófitas dominantes e das frações foliares de Mauritia flexuosa (buriti), sendo o aporte de carbono orgânico dissolvido mapeado nos trechos de amostragem. A composição, riqueza e abundância das comunidades de microinvertebrados fitófilos (Protista, Rotifera e Crustacea) foram pesquisadas e a distribuição espaço temporal dos organismos zooperifíticos descrita numa abordagem interativa com as variáveis limnológicas e ecofísicas da vereda / Abstract: The main purpose of this work was to characterize the vereda Curral das Éguas in its state of conservation, by means of inquiring its natural resources, which integrate a set of limnological and ecomorfological indicators. This vereda is inserted in the headspring affluent of the São Francisco river basin, localized in the region of Três Marias, Minas Gerais State. For that intention were selected four stretches, based in the different functional zones, through the longitudinal gradient of vereda system. The samplings were collected in five representative periods of hidrological cycle, based on resource available in the habitat. The evaluation protocol was applied to semiquantify the physical attributes, and assess habitat quality of the stream bed, margins and surrounding environment. The limnological aspects had been searched through the physical, chemical and biological variables of the water. The principal sources of organic carbon had been studied by means leaching potential of the dominant macrophytes and buritis (Mauritia flexuosa) fractions of the leaves. The contributions of organic carbon dissolved were mapped in the sampling stretches. The composition, richness and abundance of microinvertebrates phytophylous community (Protista, Rotifera and Crustacea) were searched, and the spatial temporal distribution of the organisms, described in a interative abordation with the ecophysical and liminological variables / Doutor

Submitted by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-12T12:18:43Z No. of bitstreams: 1 MELLO_Bruno Gomes_2014.pdf: 2169418 bytes, checksum: 157bccc008d9bb3bac70c082f1d983c3 (MD5) / Approved for entry into archive by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-12T12:18:51Z (GMT) No. of bitstreams: 1 MELLO_Bruno Gomes_2014.pdf: 2169418 bytes, checksum: 157bccc008d9bb3bac70c082f1d983c3 (MD5) / Approved for entry into archive by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-12T12:19:00Z (GMT) No. of bitstreams: 1 MELLO_Bruno Gomes_2014.pdf: 2169418 bytes, checksum: 157bccc008d9bb3bac70c082f1d983c3 (MD5) / Made available in DSpace on 2017-01-12T12:19:08Z (GMT). No. of bitstreams: 1 MELLO_Bruno Gomes_2014.pdf: 2169418 bytes, checksum: 157bccc008d9bb3bac70c082f1d983c3 (MD5) Previous issue date: 2014-05-22 / Não recebi financiamento / The growing interest in studies of functional diversity allows to address the relationship between the functional characteristics of species with variations in the environment attempt to understand the organization of biological communities. We examined the relationship between physical and structural characteristics of 19 stretches of headwater streams in the Atlantic Forest and morphological characteristics related to swimming ability of fish species. The environment was described by altitude, distance from species pool, substrate composition and depth of the channel. The functional characteristics were described by 11 morphological measurements. The RLQ analysis was used and the first two axes explained 97.8% of the total variation. The first axis was interpreted as the action of the altitudinal/longitudinal gradient in the structuring of assemblies of fish which varied with morphological measurements of length of caudal fin and caudal peduncle. We can say that there are two distinct assemblies positioned at the extremes of the environmental gradient separated by capacity of swimming of the species. Within these groups we can say that on a local scale the physical structure of the channel generates subgroups related to the use of the niche, suggesting the action of environmental filters. Thus, we present evidence that environmental attributes of headwaters of the Atlantic Forest are related to the structure of the assemblies of fishes that inhabit these environments. / O crescente interesse por estudos de diversidade funcional permite abordar a relação entre as características funcionais das espécies com variações no ambiente buscando entender a organização das comunidades biológicas. Nós examinamos a relação entre as características físicas e estruturais de 19 trechos de riachos de cabeceira na Mata Atlântica e as características morfológicas relacionadas com a capacidade de natação das espécies de peixes. O ambiente foi descrito quanto à altitude, distância da fonte de espécies, composição do substrato e profundidade do canal; enquanto que as características funcionais foram descritas por 11 medidas morfológicas. Utilizamos uma análise RLQ e os dois primeiros eixos explicaram 97,8% do total da variação. O primeiro eixo foi interpretado como a ação do gradiente altitudinal/longitudinal na estruturação das assembleias de peixes que variou com as medidas morfológicas de comprimento da nadadeira e pedúnculo caudal. Podemos afirmar que existem duas assembleias distintas posicionadas nos extremos do gradiente ambiental separadas pela capacidade de deslocamento das espécies. Dentro destes grupos podemos dizer que em escala local a estrutura física do canal gera subgrupos relacionados ao uso do nicho, sugerindo a ação de filtros ambientais. Desta forma, apresentamos evidências de que a estrutura das assembleias de peixes está relacionada com atributos ambientais de riachos de cabeceira da Mata Atlântica.

Made available in DSpace on 2014-12-17T14:02:03Z (GMT). No. of bitstreams: 1 RodrigoHSL.pdf: 949532 bytes, checksum: 002bc2e62935e2a735e2ed08ebe15992 (MD5) Previous issue date: 2006-08-18 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Ecomorphology is a science based on the idea that morphological differences among species could be associated with distinct biological and environmental pressures suffered by them. These differences can be studied employing morphological and biometric indexes denominated Ecomorphological attributes , representing standards that express characteristics of the individual in relation to its environment, and can be interpreted as indicators of life habits or adaptations suffered due its occupation of different habitats. This work aims to contribute for the knowledge of the ecomorphology of the Brazilian marine ichthyofauna, specifically from Galinhos, located at Rio Grande do Norte state. 10 different species of fish were studied, belonging the families Gerreidae (Eucinostomus argenteus), Haemulidae (Orthopristis ruber,Pomadasyscorvinaeformis,Haemulonaurolineatum,Haemulonplumieri,Haemulonsteindachneri), Lutjanidae (Lutjanus synagris), Paralichthyidae (Syaciummicrurum), Bothidae (Bothus ocellatus) and Tetraodontidae (Sphoeroidestestudineus), which were obtained during five collections, in the period time of September/2004 to April/2005, utilizing three special nets. The ecomorphological study was performed at the laboratory. Eight to ten samples of each fish specie were measured. Fifteen morphological aspects were considered to calculate twelve ecomorphological attributes. Multivariate statistical analysis methods such as Principal Component Analysis (PCA) and Cluster Analysis were done to identify ecmorphological patterns to describe the data set obtained. As results, H.aurolineatumwas the most abundant specie found (23,03%) and S.testudineusthe less one with 0,23%. The 1st Principal component showed variation of 60,03% with influence of the ecomorphological attribute related to body morphology, while the 2nd PC with 23,25% variation had influence of the ecomorphological attribute related to oral morphology. The Cluster Analiysis promoted the identification of three distinct groups Perciformes, Pleuronectiformes and Tetraodontiformes. Based on the obtained data, considering morphological characters differences among the species studied, we suggest that all of them live at the medium (E.argenteus,O.rubber, P.corvinaeformis,H.aurolineatum,H.plumieri,H.steindachneri,L.synagris) and bottom (S.micrurum,B.ocellatus,S.testudineus) region of column water. / A Ecomorfologia fundamenta-se na id?ia de que as diferen?as morfol?gicas existentes entre as esp?cies podem estar associadas ? a??o de diferentes press?es ambientais e biol?gicas por elas sofridas. Estas diferen?as podem ser estudadas atrav?s do emprego de ?ndices morfo e biom?tricos denominados atributos ecomorfol?gicos, representando padr?es que expressam caracter?sticas do indiv?duo em rela??o ao seu meio e podem ser interpretados como indicadores de h?bitos de vida ou de adapta??es das esp?cies ? ocupa??o de diferentes habitats. Este trabalho tem como objetivo contribuir para o conhecimento ecomorfol?gico da ictiofauna marinha brasileira, especificamente no litoral do Rio Grande do Norte, no munic?pio de Galinhos atrav?s do estudo de 10 esp?cies de peixes marinhos sendo pertencentes ?s fam?lias Gerreidae (Eucinostomus argenteus), Haemulidae (Orthopristis ruber, Pomadasys corvinaeformis, Haemulon aurolineatum, Haemulon plumieri, Haemulon steindachneri), Lutjanidae (Lutjanus synagris), Paralichthyidae (Syacium micrurum), Bothidae (Bothus ocellatus) e Tetraodontidae (Sphoeroides testudineus), que foram obtidas em 5 coletas por meio de tr?s malhos (arrasto), entre o per?odo de setembro/2004 a abril/2005. O estudo ecomorfol?gico foi realizado em laborat?rio, atrav?s das medidas de 8 a 10 exemplares de cada esp?cie, e realizado 17 medidas morfom?tricas e delas calculado 12 atributos ecomorfol?gicos. Para identificar padr?es ecomorfol?gicos que descrevem o conjunto de dados analisados foram utilizados os m?todos estat?sticos de an?lise multivariada como an?lise de componentes principais (PCA) e an?lise de agrupamento (Cluster Analysis). Como resultados obtiveram-se H. aurolineatum como maior representante com 26,16% e S. testudineus o menor com 0,23% de indiv?duos. O 1? Componente Principal com 60,03% da varia??o teve influ?ncia de atributos ecomorfol?gicos relacionados ? morfologia do corpo, e o 2? CP com 23,25% teve influ?ncia dos atributos ecomorfol?gicos relacionados ? morfologia bucal. O cluster proporcionou a identifica??o de 3 grupos, um pertencente a fam?lia dos Perciformes, um dos Pleuronectiformes e um dos Tetraodontiformes. Os dados foram analisados, diferenciando as esp?cies por seus caracteres morfol?gicos, os quais indicaram esp?cies habitantes de regi?es medianas (E. argenteus, O. ruber, P. corvinaeformis, H. aurolineatum, H. plumieri, H. steindachneri, L. synagris) e de fundo (S. micrurum, B. ocellatus, S. testudineus) da coluna d ?gua

Submitted by (ana.araujo@ufrpe.br) on 2016-08-23T12:27:17Z No. of bitstreams: 1 Miguel Santana de Almeida Neto.pdf: 1157651 bytes, checksum: 9441b1beb74a542d2c1f48a97e3fcee5 (MD5) / Made available in DSpace on 2016-08-23T12:27:18Z (GMT). No. of bitstreams: 1 Miguel Santana de Almeida Neto.pdf: 1157651 bytes, checksum: 9441b1beb74a542d2c1f48a97e3fcee5 (MD5) Previous issue date: 2012-12-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The morphological patterns shown in the species result from the interactions between their phenotype, genotype, and environment through adaptive and evolutionary processes. Thus, this study aims to evaluate the role of phylogeny and feeding in the morphological patterns of the species of Characiformes order, testing the hypothesis that the environmental pressure interferes in the morphological patterns presented by species causing morphological divergence or convergence between them. The site selected for this research was the pond Curralinho, an marginal pond of the Rio São Francisco, located in the state of Pernambuco. In this work we used the twelve species of the Order Characiformes more abundant in the ecosystem evaluated, which were captured in the period from March/2007 to February/2008 Through morphological data and diet analysis, we found that segregation of Characiformes in morphologically distinct groups, reflecting dietary differences. Therefore, morphologically similar species tending to occupy the same trophic guild. The piscivorous Acestrorhynchus britskii, Acestrorhynchus lacustris, Hoplias malabaricus, Serrasalmus brandtii and Pygocentrus piraya showed morphological characteristics that allowed ingest relatively large prey. However, we observed differences in the efficacy of swimming performance of these piscivorous, indicating that the piscivorous that eat whole fish exhibit greater agility swimming performance in order to capture your evasive preys that presented adaptations to avoid and escape the predators. The species Roeboides xenodon and Leporinus reinhardti also preferably used fish in their diets, however, the morphology of these species did not show any adjustments found in majority of the piscivorous. The less swimming speed was evidentiated among the members of the guilds insectivorous and omnivorous, that using food items with lower mobility than fish, like insects, or immobile, such as vegetables. This lower efficiency in swimming performance does not seem to characterize a disadvantage for these species. These appear to preferentially occupy the margin of the water body, which offers greater resource availability for these fish. The relationship between morphology and trophic ecology was confirmed by the Mantel test. This test indicated that the ecological structure of the taxocenosis evaluated probably been shaped by evolutionary adaptations for use of a given resource. These adaptations may be evident when we observe the processes of adaptive convergence and divergence. / Os padrões morfológicos apresentados pelas espécies resultam da interação entre seu fenótipo, genótipo e ambiente, através de processos adaptativos e evolutivos. Dessa forma, este trabalho objetiva avaliar o papel da filogenia e do hábito alimentar nos padrões morfológicos das espécies da Ordem Characiformes, testando a hipótese de que a pressão ambiental interfere nos padrões morfológicos apresentados pelas espécies a ponto de causar divergência ou convergência morfológica entre elas. O local selecionado para esta pesquisa foi a lagoa Curralinho, uma lagoa marginal do Rio São Francisco, localizada no estado de Pernambuco. Neste trabalho foram utilizadas as doze espécies da Ordem Characiformes mais abundantes no ecossistema avaliado, sendo elas capturadas no período de março/2007 a fevereiro/2008. Através de dados morfológicos e análise da dieta, verifica-se que a segregação dos Characiformes em grupos morfologicamente distintos, refletiu de um modo geral, suas diferenças alimentares, com as espécies morfologicamente semelhantes propendendo a ocupar uma mesma categoria trófica. Os piscívoros Acestrorhynchus britskii, Acestrorhynchus lacustres, Hoplias malabaricus, Pygocentrus piraya e Serrasalmus brandtii apresentaram características morfológicas que os permitiram ingerir presas relativamente maiores. No entanto entre esses piscívoros observam-se diferenças na eficiência natatória, indicando que os piscívoros que ingerem peixes inteiros apresentam uma maior agilidade natatória para capturar suas presas evasivas, que se deslocam e apresentam adaptações para fugir de seus predadores. As espécies Roeboides xenodon e Leporinus reinhardti, também utilizaram preferencialmente peixes em suas dietas, no entanto, a morfologia dessas espécies não apresentou as adaptações encontradas na maioria dos piscívoros. A menor velocidade de natação foi evidenciada entre os integrantes das categorias insetívora e onívora, que utilizam itens alimentares com menor mobilidade que os peixes, como os insetos, ou imóveis, como os vegetais. Esta menor eficiência natatória não parece caracterizar uma desvantagem para essas espécies, visto que essas parecem ocupar preferencialmente as margens do corpo d’água, que oferece uma maior disponibilidade de recursos para estes peixes. A relação entre morfologia e ecologia trófica, confirmada pelo teste de Mantel, indica que provavelmente a estruturação ecológica da taxocenose avaliada vem sendo conformada por adaptações evolutivas para utilização de um determinado recurso. Essas adaptações podem ser evidenciadas, quando se observam os processos de convergência e divergência adaptativas.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-30T14:05:00Z No. of bitstreams: 2 Dissertação - Renan Nunes Costa - 2014.pdf: 650263 bytes, checksum: 0a242695b84bbbe8d03ab17bd0c2d681 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-30T14:30:09Z (GMT) No. of bitstreams: 2 Dissertação - Renan Nunes Costa - 2014.pdf: 650263 bytes, checksum: 0a242695b84bbbe8d03ab17bd0c2d681 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-30T14:30:09Z (GMT). No. of bitstreams: 2 Dissertação - Renan Nunes Costa - 2014.pdf: 650263 bytes, checksum: 0a242695b84bbbe8d03ab17bd0c2d681 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / There is a consensus among researchers in the world that the declining number of amphibian species and the increasing frequency of abnormalities in individual attributes of anurans are associated with habitat reduction and environmental contamination. With advance of agriculture crops, also increased the use of agrochemicals defensives, and the fragility of Brazilian laws for aquatic environmental protection burst the level of environmental stress significantly. Organisms can show biological responses related to these environmental modifications, that can be used to assess the environmental impact of agricultural practices. This biological response can be particularly useful, especially when we are able to correlate the biological response in morphological and/or physiological attributes with environmental impacts. The fluctuating asymmetry (FA) is a tool based on observation of deviations in the homeostasis of bilateral traits throughout the organism development and can be used for biomonitoring protocols. The FA can clarify which type of stressor is acting on a population. In this context, the present study assesses how the FA in anurans larvae can elucidate the impact of stressful factors. In the first chapter, our objective was to test experimentally if exposure to glyphosate dosages (Roundup® Original herbicide) affect the survival and increase the development deviations in the Physalaemus cuvieri larvae. In acute exposure, the survival rate was decreased at higher levels of contamination and the LC50 observed was considered to moderately toxic. In the chronic exposure, resulting from contamination, individuals showed higher levels of FA in relation to control larvae. In the second chapter, based on field sampling, our objective was to assess if reduction of physical habitat integrity, expressed by land use and reduction of marginal vegetation near to water bodies, reflected in higher levels in fluctuating asymmetry in P. cuvieri and Scinax fuscomarginatus larvae. In this case, with increased level of impact on the surrounding matrix, the larvae of both species showed increased of FA levels. In S. fuscomarginatus, the FA levels were also higher in environments with lower percentage of edge vegetation. In summary, it’s observed that increasing environmental stress, either through contamination by glyphosate or increased anthropogenic modification of the margins of water bodies, reflects in the higher development deviations on the frog’s larvae. The affected structures can be associated with sensory capabilities of the species, in which the increased frequency of these deviations can reduce individual fitness and influence the population homeostasis over time, directly contributing to species declines. / Há um consenso entre os pesquisadores do mundo de que a redução do número de espécies de anfíbios e o aumento da frequência de anormalidades nos atributos individuais estão associados à redução e à contaminação de hábitats. Com o avanço dos cultivos agrícolas, o aumento da aplicação de produtos químicos e a fragilidade das leis de proteção de ambientes aquáticos, os níveis de estresse ambiental aumentam significativamente. Dessa forma, as respostas biológicas podem favorecer as avaliações de impacto ambiental, principalmente em espécies que apresentam plasticidade em seus atributos comportamentais, morfológicos e/ou fisiológicos, como as larvas de anuros. A assimetria flutuante (AF) é uma ferramenta que se baseia na observação de desvios na homeostase do desenvolvimento de caracteres bilaterais e pode favorecer o biomonitoramento, esclarecendo qual tipo de fator estressante está agindo sobre uma população. Neste contexto, o presente estudo avalia como a assimetria flutuante em larvas de anuros pode elucidar o impacto de fatores estressantes. No primeiro capítulo, o objetivo foi testar, experimentalmente, se a exposição a doses de glifosato (herbicida Roundup® Original) afetam a sobrevivência e aumentam os desvios no desenvolvimento de larvas da espécie Physalaemus cuvieri. Na exposição aguda, a taxa de sobrevivência foi reduzida em níveis maiores de contaminação e o LC50 observado foi considerado moderadamente tóxico. Na exposição crônica, decorrente da contaminação, os indivíduos apresentaram maiores níveis de AF em relação às larvas do controle. No segundo capítulo, baseado em coletas de campo, o objetivo foi avaliar se a redução da integridade física dos hábitats, expressa pelo uso do solo nas proximidades e pela redução da vegetação marginal nos corpos d’água, refletem em maiores níveis de assimetria flutuante nas larvas de P. cuvieri e Scinax fuscomarginatus. Neste caso, com o aumento do nível de impacto na matriz circundante, as larvas de ambas as espécies apresentaram um aumento dos níveis de AF. Em S. fuscomarginatus, os níveis de AF também foram maiores em ambientes com menor porcentagem de vegetação nas bordas. Em suma, observa-se que o aumento do estresse ambiental, seja pela contaminação por glifosato ou pelo aumento da influência antrópica nas margens dos corpos d’água, reflete em maiores desvios no desenvolvimento das larvas de anuros. As estruturas afetadas podem estar associadas à capacidade sensorial das espécies, no qual o aumento da frequência destes desvios pode reduzir a aptidão individual e influenciar a homeostase da população ao longo do tempo, contribuindo diretamente com o declínio de espécies.