Thesis deals with the mapping of our species of amphibians and reptiles in the hills of St. Thomas and the right bank of Lipno. Findings of older data in the atlas and the lack of extension work to monitor the biodiversity of species inspired me to map the location. Alignment of the square with the border position was more than 40 years, closed intensive human activities. This reasoning was that the richness and diversity of amphibians and reptiles could be acknowledge. The aim was to monitor the designated area and to identify the occurrence of individual species of amphibians and reptiles. Locate their habitats in which they propose to Match and protect this natural heritage for the future.

Le Plateau des Guyanes a été géologiquement stable au cours de l'ère Cénozoïque, exempt de l'influence de l'orogénèse des Andes et de la mise en place du bassin de l'Amazone. Cette région est-elle biogéographiquement homogène au sein de l'Amazonie ? Quelles sont les modalités spatio-temporelles de diversification au sein de cette région ? Afin de répondre à ces questions, j'ai exploré sa biorégionalisation sur la base de la distribution des amphibiens anoures. Cette approche a permis de définir trois biorégions dans l'est du Plateau des Guyanes, et de révéler une forte sous-estimation de l'endémisme. Ensuite, j'ai étudié les patrons de diversification au sein du genre endémique Anomaloglossus. Ce volet a permis de dévoiler l'existence de spéciation cryptique au sein du genre, avec un patron biogéographique composé de quatre zones de diversification au sein du Plateau des Guyanes et une origine du genre dans les tepuis. / The Guiana Shield has been geologically stable during the Cenozoic era, exempt of the influence of the uplift of the Andes and the setting up of the Amazon basin. Is this region biogeographically homogeneous within Amazonia? What are the spatio-temporal diversification modalities within this region? To answer these questions, I explored bioregionalisation within Amazonia and the Guiana Shield based on the dis- tribution of anuran amphibians. This approach enabled to define three bioregions in the eastern Guiana Shield and to reveal a high underestimation of endemism. Then, I studied the diversification patterns within the endemic frog genus Anomaloglossus. This part en- abled to reveal cryptic speciation within the genus, and a biogeographic pattern composed of four areas of diversification in the Guiana Shield, with an origin of the genus in the western highlands (tepuis).

Made available in DSpace on 2014-06-11T19:22:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-18Bitstream added on 2014-06-13T19:08:31Z : No. of bitstreams: 1 juares_am_me_sjrp.pdf: 1255291 bytes, checksum: f62b5b9e2c66b7cee6292143d0f8bda6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A Floresta Atlântica é o bioma com maior diversidade e taxa de endemismo de anfíbios anuros do mundo. Esse bioma consiste em sua maior parte de pequenos fragmentos isolados, ainda sob intensa pressão antrópica, colocando em risco a sua biodiversidade. Os anfíbios são especialmente susceptíveis à degradação ambiental devido a sua fisiologia ectotérmica, a pele permeável, a sua vulnerabilidade a diversos agentes biológicos ou químicos e por apresentarem ovos e larvas dependentes da água ou de ambiente úmidos. Tais características fazem destes animais bons modelos para o estudo de questões relacionadas à modificação de hábitats, sejam elas relativas à identificação de padrões ou inferência sobre processos associados à fragmentação ou perda do hábitat original, ou mesmo ocupação e colonização em áreas alteradas. Dentro deste contexto, este trabalho teve como objetivos principais, (1) determinar a diversidade e a estrutura de uma comunidade de anfíbios anuros e (2) investigar a possível influência do tipo de formação vegetal na composição da anurofauna terrestre, em uma região de domínio Atlântico, localizada na Serra da Mantiqueira entre os Municípios de Piquete, SP, e Marmelópolis, MG00; (22°29’37,9” a 22°31’15,7” S e 45°08’57,8” a 45°09’35,4” W; 1500 a 1640m). A partir do inventário mensal das espécies em campo durante 23 meses consecutivos para o primeiro objetivo e por 12 meses consecutivos para o segundo, utilizando-se dos métodos de procura visual e auditiva e de armadilhas de interceptação e queda, foram determinadas a abundância, a riqueza e as distribuições espaciais e temporais de anuros em diferentes áreas: mata secundária tardia, mata de araucária, plantações de Eucalyptus sp, riachos, poças permanentes e temporárias em área aberta e interior de floresta e brejos de borda de mata e de área aberta... / The Atlantic Forest is the biome with the highest diversity and rate of endemism for anuran amphibians in the world. This biome currently consists mostly of isolated small forest remnants under high anthropogenic pressure, threatening its biodiversity. Amphibians are especially susceptible to environmental degradation due to their physiology, permeable skin, and their vulnerability to several biological or chemicals agents and for having eggs and larvae that depend on water or humid environments to complete their development. These features make them useful models to study the effects of hábitat change, e.g., the identification of patterns and processes associated with fragmentation or hábitat loss, or even the occupation and colonization in disturbed areas. Within this context, the main aims of this study are: (1) to determine the diversity and the structure of an anuran community and (2) to investigate the influence of vegetation type on the composition of leaf litter frogs in an Atlantic Forest area, located in the Mantiqueira mountain range between Piquete, state of São Paulo and Marmelópolis, state of Minas Gerais (22° 29' 37.9 S; 45° 08' 57.8 W and 22° 31' 15.7 S; 45° 09' 35.4 W, 1500 to 1640 m a.s.l.). I conducted 23 monthly samplings using visual and acoustical survey techniques and 12 monthly samplings using pitfall traps to estimate the abundance and richness and to determine the spatial and temporal distributions of anurans in several areas: late secondary forest, Araucaria forest, Eucalyptus woodlots, streams, permanent and temporary ponds in open and forested areas, and swamps at the forest edge and open areas. I recorded 32 species, 15 of which using pitfall traps. The species richness and abundance were different in the hábitats sampled. The forest hábitats had the highest richness (n = 16) and abundance (n = 432). Litter depth was positively correlated... (Complete abstract click electronic access below)

Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-29T10:19:06Z No. of bitstreams: 2 Dissertação - Raísa Romênia Silva Vieira - 2014.pdf: 1011765 bytes, checksum: 06f099206f2cd97d31e4cd7702e94f21 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-30T10:18:15Z (GMT) No. of bitstreams: 2 Dissertação - Raísa Romênia Silva Vieira - 2014.pdf: 1011765 bytes, checksum: 06f099206f2cd97d31e4cd7702e94f21 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-30T10:18:15Z (GMT). No. of bitstreams: 2 Dissertação - Raísa Romênia Silva Vieira - 2014.pdf: 1011765 bytes, checksum: 06f099206f2cd97d31e4cd7702e94f21 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-05-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Small water bodies (e.g. ponds, small lakes) are distributed in many landscapes and are commonly found in agricultural areas. These water bodies are important in maintaining regional biodiversity because they support heterogeneous communities of aquatic organisms. The differences in local and regional environmental features may explain beta diversity and which process, nestedness or turnover, is more important in these anthropogenic landscapes. In this work we aim to answer how local and regional factors affect the richness and variation in species composition of anurans in agricultural landscapes. We sampled amphibians in 68 water bodies in the surroundings of Goiânia municipality. Species turnover is the main phenomenon occurring in the landscape and this pattern differs from a null distribution. Environmental heterogeneity was the main variable affecting richness and beta diversity of frogs. The presence of species in the sampled area is mainly related to the availability of different microhabitats, both vertically and horizontally, which support particular requirements of the species. Is crucial to differentiate the nestedness and turnover phenomena to understand the processes that determine the organization of communities. / Pequenos corpos d’água (e.g. poças, pequenos lagos) estão distribuídos em diversas paisagens, sendo comumente encontrados em áreas de agropecuária. Essas áreas são importantes na manutenção da biodiversidade regional, pois suportam comunidades heterogêneas de organismos aquáticos. As diferenças nas características ambientais locais e regionais podem explicar a diversidade beta encontrada e qual processo, aninhamento ou substituição de espécies, é mais significativo nessas paisagens antrópicas. Neste trabalho objetivamos responder como fatores locais e regionais afetam a riqueza e a variação na composição de espécies de anuros em áreas de agropecuária. Nós amostramos anfíbios anuros em 68 corpos d’água no entorno da cidade de Goiânia. A substituição de espécies é o principal fenômeno existente na paisagem e esse padrão difere de uma distribuição nula. A heterogeneidade ambiental foi a principal variável afetando a riqueza e a diversidade beta de anuros. A presença de anuros na área amostrada está relacionada principalmente com a disponibilidade de diferentes micro-habitats, tanto vertical quanto horizontalmente, que suportam requisitos particulares das espécies. Para compreendermos os processos que determinam a organização das comunidades é crucial diferenciarmos os fenômenos de aninhamento e substituição de espécies.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-07-14T14:59:37Z No. of bitstreams: 2 Dissertação - Mateus Atadeu Moreira - 2015.pdf: 3009996 bytes, checksum: 1a2c29fc3dae91ef371d08eaa0f6b9e2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-07-14T15:01:03Z (GMT) No. of bitstreams: 2 Dissertação - Mateus Atadeu Moreira - 2015.pdf: 3009996 bytes, checksum: 1a2c29fc3dae91ef371d08eaa0f6b9e2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-07-14T15:01:03Z (GMT). No. of bitstreams: 2 Dissertação - Mateus Atadeu Moreira - 2015.pdf: 3009996 bytes, checksum: 1a2c29fc3dae91ef371d08eaa0f6b9e2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / We only have described a small fraction of the world’s biodiversity. The influence of how much we know biodiversity and how that hinders our strategies for conserving it is a genuine and weighty concern. Brazil has the greatest amphibian diversity in the world with 1026 amphibian species, and the number of described species is increasing at a high rate. It is likely that many of these Brazilian amphibians still undescribed are threatened. Although many new species are being described in Brazil some protected areas are being downsized or downgraded. In this study we aim to analyze how much the Linnean shortfall impairs our ability to prioritize areas for the conservation of a highly diverse and still poorly known group such as the Brazilian amphibians, and whether the main conservation strategy in Brazil is prepared to deal with this shortfall. We made four spatial prioritizations of the known Brazilian amphibians of four arbitrarily chosen scenarios (1980, 1990, 2000 and 2013), then we overlapped these prioritizations with the existing federal protected areas of each scenario, and compared the results, calculating the proportions of the high priority areas that changed place and the proportion of high priority areas federally protected at each scenario. In the first change of scenario 921 of the 4672 cells that comprises the seventeen per cent of highest priority cells in 1980 changed place to form the seventeen per cent most priority cells in 1990 (19,71% of the cells). On the 1990-2000 change 905 of the 4686 cells changed place (19,31%) and on the last change of scenario (2000-2013) 983 of the 4675 (21,01%) highest priority cells has changed place. The percentage of these highest priority areas that was federally protected at each scenario and in each of the biomes was severely low in all cases, but is maidenly rising with time. The new protected areas created between the scenarios (both the strict protection and sustainable use areas) do not follow the new priority areas. It is crucial that Brazilian taxonomy continues to grow. Since Brazil is so important for the future of the global diversity of amphibians is also crucial a systematic planning of new protected areas, using scientific models to account for the Linnean shortfall, in order to protect such an astonishing diversity. Keywords: Linnean shortfall, Biodiversity, Conservation, Brazilian Amphibians, Spatial Conservation Prioritization / A ciência descreveu menos da metade do número total de espécies existentes. A influência do quanto conhecemos ou não a biodiversidade e o quanto isso pesa nas nossas estratégias de conservação é uma preocupação genuína e séria. O Brasil possui a maior diversidade de anfíbios do mundo com 1026 espécies, e esse número tem crescido em uma alta taxa. É provável que muitos dos anfíbios que ainda não foram descritos no Brasil estejam ameaçados. Enquanto muitas espécies têm sido descritas ultimamente o Brasil está diminuindo o tamanho e o grau de proteção de diversas áreas protegidas. Nesse estudo avaliamos o quanto a lacuna Linneana afeta a definição de áreas prioritárias para a conservação de um grupo altamente diverso e ainda pobremente conhecido como os anfíbios do Brasil, e se a principal estratégia de conservação brasileira está preparada pra lidar com essa lacuna. Nós fizemos quatro priorizações espaciais da fauna de anfíbios conhecida no Brasil em quatro cenários no tempo (1980, 1990, 2000 e 2013), em seguida sobrepusemos essas priorizações com as Unidades de Conservação Federais de cada um desses cenários e comparamos os resultados. Calculamos o quanto a configuração das áreas mais prioritárias mudou de um cenário para outro e o quanto das áreas mais prioritárias estava protegido em cada cenário. De 1980 para 1990, 921 das 4672 células mais prioritárias mudaram de lugar (19,71% das células). De 1990 para 2000, 905 das 4686 células mudaram (19,31%) e na última mudança de cenário (2000-2013) 983 das 4675 (21,01%) tiveram mudança espacial. A proporção dessas áreas mais importantes para conservação que estava protegida em cada cenário e em cada bioma foi muito pequena, mas está crescendo modestamente com o tempo. As novas Unidades de conservação criadas entre os cenários não acompanham as novas áreas mais prioritárias que surgem com o acréscimo das novas espécies. Sendo o Brasil tão importante para a proteção da tão ameaçada fauna global de anfíbios é crucial que exista um planejamento sistemático de novas áreas protegidas, e que esse planejamento use modelos científicos para levar em conta a lacuna Linneana.

Orientador: Luciana Bolsoni Lourenço Morandini / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T20:53:49Z (GMT). No. of bitstreams: 1 Rodrigues_DeboraSilva_M.pdf: 3296545 bytes, checksum: 2a2ccc454f9a1df9f09173c2127af330 (MD5) Previous issue date: 2012 / Resumo: O gênero Engystomops apresenta ampla distribuição geográfica e constitui um interessante grupo de anuros para estudos cariotípicos. As populações de Engystomops encontradas na Amazônia têm sua identificação taxonômica ainda controversa. Análises genéticas e citogenéticas apoiam hipóteses que sugerem a existência de um complexo de espécies crípticas e especiação incipiente. Muitas vezes a variação citogenética observada entre diferentes populações estudadas dificultou o reconhecimento de homeologias cromossômicas entre os cariótipos. Uma caracterização cromossômica mais detalhada poderia auxiliar no possível reconhecimento de homeologias cromossômicas e, dessa forma, contribuir para o estudo dos processos envolvidos na divergência desses anuros. Já que o gene do DNAr 5S tem sido importante marcador genético e citogenético para estudos evolutivos e para a identificação e comparação de espécies em diversos grupos, no presente trabalho o DNAr 5S de Engystomops freibergi e de exemplares de Engystomops petersi de duas localidades Equatorianas (Puyo e Yasuní) foi estudado. Em todos os casos, dois tipos de DNAr 5S, facilmente diferenciados pelo tamanho e composição da sequência do seu espaçador não transcrito, foram isolados. A provável região promotora do gene do RNAr 5S (ICR) foi localizada nos dois tipos de sequências de DNAr 5S e a presença de possíveis sequências regulatórias adicionais foi discutida. No cariótipo de E. freibergi, sonda contendo a unidade repetitiva do DNAr 5S tipo I hibridou na região pericentromérica do braço curto dos cromossomos do par 3, e o DNAr 5S tipo II foi mapeado na região distal do braço longo dos cromossomos do par 6. A sonda formada somente pela região de NTS do DNAr 5S tipo I claramente detectou a região pericentromérica de 3p nos cariótipos de E. freibergi e E. petersi (Puyo) e de 5p no cariótipo de E. petersi (Yasuní), porém nenhum sinal distal ou intersticial foi observado. A sonda formada pela região de NTS do DNAr 5S tipo II detectou apenas a região distal de 6q nos três cariótipos estudados, corroborando a distribuição diferencial dos dois tipos de DNAr 5S nesses cariótipos. Tais sítios de DNAr 5S constituem novos marcadores cromossômicos, os quais permitem sugerir a homeologia entre o cromossomo 6 dos cariótipos de E. freibergi e de E. petersi, e entre o cromossomo 5 do cariótipo de E. petersi de Yasuní e o cromossomo 3 dos cariótipos de E freibergi e de E. petersi de Puyo. Já que os dois tipos de DNAr 5S encontrados em Engystomops são relacionados àqueles de Physalaemus tanto quanto à composição nucleotídica quanto à localização cromossômica, é ainda possível inferir que a origem desses dois tipos de sequências tenha antecedido a divergência evolutiva desses gêneros / Abstract: The Engystomops genus is widely distributed geographically and constitutes an interesting group for karyotypic studies. The taxonomic identifications of Amazonian populations of Engystomops is still controversial. Genetic and cytogenetic analyses suggest the existence of a complex of cryptic species and incipient speciation. The cytogenetic variations found among some populations prevent the recognition of chromosomal homeologies between the described karyotypes. A more detailed chromosomal characterization could help in the recognition of chromosome homeologies and, therefore, could contribute to the study of the processes involved in the divergence of these anurans. Since the 5S rDNA gene has been an important genetic and cytogenetic marker for evolutionary studies and even for the identification and comparison of species in diverse groups, in the present work the 5S rDNA of Engystomops freibergi and exemplars of Engystomops petersi from two Ecuadorian locations (Puyo and Yasuní) was studied. In all cases, two types of 5S rDNA, easily differed by size and compositon of their non-transcribed spacer, were isolated. A putative promoting region of the 5S rRNA gene (ICR) was recognized in the two types of 5S rDNA sequences and the presence of possible additional regulatory sequences was discussed. In the E. freibergi karyotypes, the entire type I 5S rDNA repeating unit hybridized to the pericentromeric region of 3p, whereas the entire type II 5S rDNA repeating unit mapped to the distal region of 6q, suggesting a differential localization of these sequences. The type I NTS probe clearly detected the 3p pericentromeric region in the karyotypes of E. freibergi and E. petersi from Puyo and the 5p pericentromeric region in the karyotype of E. petersi from Yasuní, but no distal or interstitial signals were observed. Interestingly, this probe also detected many centromeric regions in the three karyotypes, suggesting the presence of a satellite DNA family derived from 5S rDNA. The type II NTS probe detected only distal 6q regions in the three karyotypes, corroborating the differential distribution of the two types of 5S rDNA. Because the 5S rDNA types found in Engystomops are related to those of Physalaemus with respect to their nucleotide sequences and chromosomal locations, their origin likely preceded the evolutionary divergence of these genera. In addition, our data indicated homeology between chromosome 5 in E. petersi from Yasuní and chromosomes 3 in E. freibergi and E. petersi from Puyo. In addition, the chromosomal location of the type II 5S rDNA corroborates the hypothesis that the chromosomes 6 of E. petersi and E. freibergi are homeologous despite the great differences observed between the karyotypes of the Yasuní specimens and the others / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Studies of biodiversity surveys and habitat requirements are essential in landscapes threatened by anthropogenic conversion, such as those that make up the Pampa biome. In the present study we determined the spatial distribution of richness of anurans at the Área de Proteção Ambiental (APA) do Ibirapuitã, the largest protected federal area within the Pampa biome in Brazil. Thus we: (1) describe the composition of anuran community regarding species richness, abundance, constancy of occurrence and reproductive modes; (2) compare the frogs composition with other localities of grassland southernmost of South America; (3) tested whether local variables of waterbodies, space and landscape are determinants of species richness, and (4) tested whether environmental heterogeneity influences the structure of anuran community. Sampling was carried from October to November 2012 and at November 2013, the searching at breeding sites method, tadpole collecting and examination of specimens housed in herpetological collections. A total of 64 waterbodies (40 ponds and 24 streams) were sampled for the anuran amphibians, as well as were recorded environmental descriptors in three scales: local, space, and landscape. We recorded the occurrence of 33 anuran species at the APA Ibirapuitã. The registered anurans are typical of open areas, and at least 10% of them are restricted of the grassland areas to the subtropical region of South America, including two endangered species at the global and state levels. Pseudopaludicola falcipes was the most abundant species and Hypsiboas pulchellus was the species most frequently recorded. Five reproductive modes were recorded, and the deposition and the development of exotrophic tadpoles in lentic waterbodies was the most common mode (57.5%). Cluster analysis revealed five groups with more than 50% similarity, whose structure was influenced by geographic distance, but can be partially interpreted by regional peculiarities. We used generalized regression models considering the set of descriptors as predictors of anuran species richness. Subsequently, we use a partition of variance to evaluate the independent and shared explicability between different sets of predictors. Finally, we use a Canonical Redundancy Analysis to explore the role of environmental descriptors on the species abundance of frogs in ponds and streams. The richness in ponds was influenced by the local variable representing the area of waterbodies. Already the abundance was correlated with the percentage of vegetation on the shores and the water temperature. In streams, the species richness of anurans was correlated with a local variable (number of strata of emergent vegetation) and a landscape variable (distance in relation to human residences). Species abundance was affected by higher vegetation strata (> 200 cm) on the shores and by water electrical conductivity. The combined contribution of local and landscape variables have important implications for understanding how amphibians are distributed in the grassland environment. Our work shows the importance of conserving grassland biomes which are increasingly threatened by human activities. / Studies of biodiversity surveys and habitat requirements are essential in landscapes threatened by anthropogenic conversion, such as those that make up the Pampa biome. In the present study we determined the spatial distribution of richness of anurans at the Área de Proteção Ambiental (APA) do Ibirapuitã, the largest protected federal area within the Pampa biome in Brazil. Thus we: (1) describe the composition of anuran community regarding species richness, abundance, constancy of occurrence and reproductive modes; (2) compare the frogs composition with other localities of grassland southernmost of South America; (3) tested whether local variables of waterbodies, space and landscape are determinants of species richness, and (4) tested whether environmental heterogeneity influences the structure of anuran community. Sampling was carried from October to November 2012 and at November 2013, the searching at breeding sites method, tadpole collecting and examination of specimens housed in herpetological collections. A total of 64 waterbodies (40 ponds and 24 streams) were sampled for the anuran amphibians, as well as were recorded environmental descriptors in three scales: local, space, and landscape. We recorded the occurrence of 33 anuran species at the APA Ibirapuitã. The registered anurans are typical of open areas, and at least 10% of them are restricted of the grassland areas to the subtropical region of South America, including two endangered species at the global and state levels. Pseudopaludicola falcipes was the most abundant species and Hypsiboas pulchellus was the species most frequently recorded. Five reproductive modes were recorded, and the deposition and the development of exotrophic tadpoles in lentic waterbodies was the most common mode (57.5%). Cluster analysis revealed five groups with more than 50% similarity, whose structure was influenced by geographic distance, but can be partially interpreted by regional peculiarities. We used generalized regression models considering the set of descriptors as predictors of anuran species richness. Subsequently, we use a partition of variance to evaluate the independent and shared explicability between different sets of predictors. Finally, we use a Canonical Redundancy Analysis to explore the role of environmental descriptors on the species abundance of frogs in ponds and streams. The richness in ponds was influenced by the local variable representing the area of waterbodies. Already the abundance was correlated with the percentage of vegetation on the shores and the water temperature. In streams, the species richness of anurans was correlated with a local variable (number of strata of emergent vegetation) and a landscape variable (distance in relation to human residences). Species abundance was affected by higher vegetation strata (> 200 cm) on the shores and by water electrical conductivity. The combined contribution of local and landscape variables have important implications for understanding how amphibians are distributed in the grassland environment. Our work shows the importance of conserving grassland biomes which are increasingly threatened by human activities.

Dans les paysages fragmentés, les mouvements entre les patchs d'habitats jouent un rôle primordial dans la persistance des populations en assurant les flux génétiques, la possibilité de recolonisation après extinction locale, la liaison entre différents habitats pour la reproduction ou l'acquisition des ressources, … Malgré l’importance de ces mouvements, la structure du paysage entre ces patchs (i.e. la matrice) est le plus souvent considérée comme un ensemble homogène de non-habitat d’intérêt mineur et les adaptations comportementales en réponse à la fragmentation du paysage sont rarement prises en compte. Pour étudier l'importance de l'influence du paysage sur les mouvements, trois approches complémentaires sont pratiquées. 1) Des études expérimentales sont menées pour évaluer les réponses comportementales et physiologiques du crapaud commun (Bufo bufo) juvénile et adulte soumis aux différents types d'occupation du sol. Ainsi, les types d'occupation du sol sont caractérisés par le coût que leur traversée représente pour l’espèce étudiée. 2) Ce travail s’attache également à décrypter les règles régissant les déplacements en paysage hétérogène et à mettre en évidence des différences comportementales selon le paysage d'origine (adaptations). 3) Basé sur la modélisation, le troisième volet doit permettre d’effectuer des prédictions à l’échelle des paysages / In fragmented landscapes, movements between habitat patches play a crucial role in population persistence by allowing gene flow, rescue effect possibilities, linking different habitats for reproduction or resources acquisition, … Although the importance of these movements, the landscape structure between patches (i.e. matrix) is too frequently considered as a homogeneous non-habitat of minor interest and behavioural adaptations in response to fragmentation are rarely taken into account. To investigate the importance of the landscape influence on movements, three complementary approaches are used: 1) experimental studies are performed to assess behavioural and physiological responses of common toads when they are confronted to different land uses. Land uses are thus characterised par the cost of their crossing for the focus species. 2) This work also aims to decipher the rules of movement in heterogeneous landscapes and to highlight behavioural differences according to the originated landscape (adaptations). 3) On the basis of modelling, the third part of this work intends to make predictions at the landscape scale

Les activités d'origines anthropiques entraînent des modifications profondes du paysage : dans ce contexte, le succès de dispersion revêt une grande importance pour la persistance à long terme des populations animales et végétales. La génétique du paysage est une discipline récente qui permet de détecter et de modéliser les flux de dispersion de manière indirecte par le biais de l'identification des flux de gènes dans l'espace. Bien qu'il ait été suggéré delongue date qu'un échantillonnage individu-centré pouvait permettre de s'affranchir de certains biais liés à unedélimitation a priorides populations, les études portant sur des organismes présentant une distribution spatiale discontinue restent malgré tout le plus souvent basées sur un échantillonnage réalisé à l'échelle populationnelle. C'est sur cette thématique qu'ont porté mes travaux de thèse. Des résultats obtenus par simulations montrent qu'augmenter le nombre de points échantillonnés dans l'espace au détriment du nombre d'individus par agrégat peut permettre une meilleure détection de l'influence de la matrice sur les flux de gènes, quelque soit le régime de dispersion et le contexte paysager considérés. Appliqué à l'étude de la dispersion du triton alpestre Ichthyosaura alpestris, d'une part en paysage fragmenté par des infrastructure linéaires de transport (isolation par barrières aux flux de gènes IBB) et d'autres part en paysage agricole (isolation par résistance de la matrice paysagère IBR), l'échantillonnage individu-centré apparaît comme une alternative flexible et efficace à l'échantillonnnage populationnel classique. / Anthropogenic activitites lead to profound landscape alterations : dispersal success thus holds a paramount importance for long-term persistence of populations. Landscape genetics is a recent discipline aiming to detect and describe dispersal patterns through indirect estimations of gene flow. Although the use of an individual-based sampling scheme has been proposed for a ;ong time to get round the issue of an a priori delimitation of population boundaries, most landscape gentic studies are still based on a population-based sampling scheme. results from simulations showed that decreasing the sampling coverage on individuals within populations in favour of a better sampling coverage of aggregates through space allowed a better detection of the impacts of landscape on gene flow, whatever the individual dispersal behaviour or the landscape configuration. when considering the dispersal patterns in the alpine newt Ichthyosaura alpestris, both in the vicinity of large transport infrastructures (Isolation-by-barrier IBB) and in agricultural landscape (Isolation-by-landscape-resistance IBR), the individual-based sampling scheme proved to be a flexible and efficient methodological alternative to the more conventional population-based sampling scheme.

Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated in three developmental stages of X. laevis, and in one developmental stage of B. woodhousii woodhousii, and R. sphenocephala. For most tissue and lipid uptake values, a significant increase was observed as exposure concentration increased. Tissue and lipid BCF values were dependent upon both stage and species. Chronic and acute effects of caffeine were determined in X. laevis larvae. Acute 96-hour LC50 values in four developmental stages were > 75,000 ug L-1 caffeine and heart rates were significantly different at the two earliest developmental stages. Larvae chronically exposed to caffeine reached metamorphosis at the same time as controls. Changes in chronic heart rate were dependent upon stage of development and exposure concentration. This research indicates that the toxicity of amphibian larvae exposed to triclosan, triclocarban, and caffeine appears to be dependent upon species and developmental stage, with early developmental stages being most sensitive to contaminant exposure.