The determination of diatom species is mostly based on morphology of a silicified cell wall. It is complicated by the fact of cell diminution during the vegetative phase of the life cycle, which is conected with shape changes and loss of some taxonomically importat characters. Even though the diminution during the life cycle is generally known phenomeon, there is a lack of studies on this theme. In this masters thesis, four monoclonal populations of model pennate diatom strains were used in order to study shape dynamics during the life cycle. The strains were cultivated for almost three years and parts of the cultures with a different size stages were fixed in permanent preparations. The digital photographs of the cells were used as a material for the geometric morphometrics analyses. The study revealed high contribution of significant allometric changes to an overall shape variability. During the vegetative phase of the life cycle, disparity of the cells increases and complexity of the cells decreases. The contribution of symetric variability to an overall shape variability is more than eighty percent. Phenotypic plasticity in a monoclonal populations is an interesting finding from an evolutionary point of view. It may indicate constraints caused by the silica cell wall. During the size diminution...

La morphométrie géométrique permet la visualisation dynamique 3D de la base du crâne et une prévision de leurs variations liées à la croissance. Le but de ce travail est de proposer des méthodes fiables et précises pour estimer l’âge fœtal et caractériser un stade de développement par sa conformation osseuse. Les os temporal, occipital et sphénoïde de 33 fœtus âgés de la 19ème à la 24ème semaine d’aménorrhée (S.A.) ont été reconstruits en 3D et 44 landmarks ont été positionnés. L’étude par morphométrie géométrique a permis de déterminer les maxima de variation morphologique, ainsi que d’étudier les trajectoires ontogénétiques. Les formules établies permettent l’estimation de l’âge à ±2,44 semaines. Les points de césure classiquement utilisés en anthropologie ont été confirmés. Nous avons établi une chronologie des conformations entre la 19ème, la 27ème et la 41ème S.A. L’os sphénoïde et occipital présentent un rythme de croissance commun alors que l’os temporal diffère. Nous avons confirmé ces structures anatomiques comme étant des critères indirects de maturation permettant d’estimer l’âge. / Geometric morphometric techniques allow the 3D visualization of the skull base and a forecast of their related growth variations. The aim of this work is to provide reliable and accurate methods to estimate fetal age and stage of development characterized by bone conformation. The temporal bone, occipital and sphenoid in 33 fetuses aged from the 19th to the 24th week of amenorrhea (W.A) were reconstructed in 3D and 44 landmarks were positioned. Geometric morphometrics was used to determine the maxima of morphological variation and ontogenetic trajectories. The established formulas allow the estimation of age at ±2.44 weeks. Hyphenation points conventionally used in anthropology have been confirmed. We have established a chronology of the conformations between 19th, 27th and 41st WA. The sphenoid and the occipital bone have a common growth rate, while the temporal bone differs. We confirmed these anatomical structures as indirect criteria of maturation to estimate age.

Il existe chez les espèces du genre Homo une diversité morphologique crânienne et cérébrale importante, et les interactions de ces deux éléments sont complexes. De manière générale, au cours de l’évolution de ce taxon, le neurocrâne prend une importance croissante par rapport au bloc facial en raison d’une expansion cérébrale marquée. Cependant, les modalités de cette expansion sont multiples, et elle se met en place chez les différentes espèces via des modifications morphologiques qui leur sont propres. Mise à part l’augmentation du volume cérébral, l’endocrâne témoigne de réorganisations neuroanatomiques. Ces différents facteurs - volume et organisation – ainsi que les contraintes morpho-fonctionnelles diverses exercées sur la face externe du crâne, sont susceptibles de résulter en une variété de relations morphologiques et spatiales entre le neurocrâne et l’endocrâne. Il est donc pertinent de documenter ces relations afin de pouvoir par la suite mieux appréhender la variabilité et les mécanismes évolutifs à l’oeuvre chez les différents taxons du genre Homo. Nous explorons dans ce travail de thèse les variations jointes du neurocrâne et de l’endocrâne dans le genre Homo et chez Homo sapiens. Cette contribution est basée sur l’analyse de modèles virtuels de crânes et d’endocrânes à l’aide de méthodes géométriques et d’une méthode innovative de déformations de surfaces. Nous avons étudié des données morphologiques issues de populations actuelles afin d’éclaircir la nature des relations entre le neurocrâne et l’endocrâne chez Homo sapiens. Pour cela, nous avons comparé les asymétries des hémisphères de l’endocrâne – qui reflètent celles des hémisphères cérébraux – aux asymétries de la voûte crânienne. Les schémas d’asymétrie bilatérale relevés sont identiques sur le crâne et sur l’endocrâne. Cela s’explique par une morphologie de la voûte du crâne calquée sur celle de l’endocrâne, malgré un effet « tampon » de l’os qui n’enregistre pas sur sa face externe toutes les asymétries cérébrales. Les possibles corrélations entre le degré d’asymétrie et des facteurs tels que la conformation générale du crâne, la robustesse des superstructures osseuses, le sexe et le volume endocrânien ont également été explorées. Nous avons ensuite analysé les schémas de co-variation entre neurocrâne et endocrâne au sein du genre Homo. Nous avons ainsi pu mettre en évidence des éléments de co-variation qui concernent l’ensemble du genre Homo, et d’autres qui sont spécifiques à certains taxons, notamment aux Néandertaliens ou à Homo sapiens. Ainsi, si la conformation de la voûte crânienne est très semblable à la morphologie endocrânienne, les interactions crâne-endocrâne dans la zone occipitale et cérébelleuse apparaissent plus variables, et semblent inféodées au degré de globularisation de l’ensemble du cerveau et du neurocrâne. Ces résultats mettent en évidence certaines interactions entre réorganisations cérébrales et morphologie crânienne chez les différentes espèces du genre Homo, et soulignent le caractère crucial du croisement des données et des méthodes pour l’interprétation du registre fossile. / Species of the genus Homo display cranial and endocranial morphological variations, with complex interactions between these two elements. Generally speaking, throughout the evolution of this taxon the neurocranium becomes increasingly important by comparison with the facial skeleton, due to a marked cerebral expansion. The modalities of this expansion differ accross species and occur at least partly through species-specific morphological processes. Apart from the increase in cerebral volume, the endocast bears the traces of neuroanatomical reorganisations. These two factors – volume and organisation – as well as various morpho-functional constraints on the external face of the cranium, may result in a variety of morphological and spacial relationships between the neurocranium and the endocranium. It is therefore important to document these relations in order to better apprehend the variability and the evolutionary mechanisms behind the morphologies of the different Homo species.This doctoral thesis explores the joint morphological variations of the neurocranium and endocast in the genus Homo and within Homo sapiens through multiple approaches. We offer a contribution to this topic based on shape analyses of virtual crania and endocasts, using geometric morphometrics and an innovative technique of surface deformations. We analysed morphological data from extant populations in order to clarify the nature of the relationship between the neurocranium and the endocast in Homo sapiens. One of the lines of evidence investigated is the correspondence between neurocranial and endocranial (and therefore cerebral) gross asymmetries. Our results show that the patterns of bilateral asymmetries of the neurocranium are identical to those of the endocranium. There is a close correspondance between the morphologies of the endocranial and cranial vaults, despite the neurocranium not displaying the full extent of cerebral asymmetries on its external vault. Correlations between asymmetry and factors including sex, endocranial volume and importance of the bony superstructures were also tested. Co-variation patterns between neurocranial and endocranial morphologies in the genus Homo were analysed. Our results highlight elements of co-variation between the neuro and endocranium which are shared accross the genus Homo, and others which are species-specific. While the cranial vault closely follows endocranial morphology, interaction patterns between the endo and neurocranium in the occipito-cerebellar area appear more variable and linked to the overall degree of globularisation of the brain and neurocranium. These results highlight some of the interactions between cerebral reorganisations and cranial morphology in Homo species, and underline the importance of crossing data and methods in order to interpret the fossil record.

O mosquito Aedes aegypti é reconhecido como o principal vetor do vírus da Dengue, além de transmitir outros arbovírus de importância médica, como os causadores da Febre Amarela urbana, Chikungunya e Zika. A ecologia deste vetor está intimamente associada ao homem, sendo provavelmente, a única espécie de culicídeo a conseguir completar todo seu ciclo de vida dentro das habitações humanas, com sua dinâmica populacional fortemente relacionada aos processos decorrente da urbanização. Assim como outras metrópoles, a cidade de São Paulo apresenta estresse ambiental, em função da elevada densidade populacional e urbanização não planejada, o que contribui para a proliferação do Ae. aegypti e, consequentemente, o aumento no número de casos de Dengue. Embora, vacinas como a da Febre Amarela e Dengue já tenham sido desenvolvidas, esta última mais recentemente e, ainda não empregada em larga escala, o controle do vetor ainda permanece como a principal estratégia para a disruptura dos padrões epidemiológicos das arboviroses causadas por seus patógenos. Estruturação populacional, geralmente é um resultado de combinações decorrentes de processos históricos e contemporâneos envolvendo determinada espécie, como a sua capacidade de dispersão, padrões de cópula, barreiras físicas e ambientais, além de padrões demográficos. Desse modo, determinar os diferentes papéis destes processos na estruturação de populações torna-se útil no controle de vetores de importância médica. Um bom exemplo é a propagação da resistência a inseticidas, em decorrência do fluxo gênico entre as populações. Portanto, um melhor conhecimento da estruturação populacional do Ae. aegypti é crucial para auxílio e desenvolvimento de novas estratégias de controle. Dessa forma, visando elucidar seu padrão de estruturação, o presente estudo utilizou-se da morfometria geométrica alar e de marcadores microssatélites, para investigação de 11 populações de mosquitos Ae. aegypti coletados em áreas com diferentes graus de urbanização, localizadas no município de São Paulo. Os resultados encontrados sugerem um padrão de estruturação de acordo com o gradiente de urbanização no qual os espécimes foram coletados. As distâncias de Mahalanobis, obtidas pela morfometria geométrica alar, apresentaram significância estatística em 54 dos 55 testes conduzidos, com as populações exibindo um claro padrão de segregação nas Análises de Variáveis Canônicas e Neighbor-Joining, tanto para as populações agrupadas na forma de seus estratos urbanos, como por seus respectivos locais de coleta, enquanto que o teste de reclassificação dos espécimes alcançou relativo grau de precisão de reconhecimento. Os microssatélites indicaram uma baixa estruturação genética (Fst = 0,057), com 93 por cento de seus valores apresentando significância estatística. Contudo, em conformidade com o gradiente de urbanização dos estratos, com moderado fluxo gênico, déficit de heterozigosidade e indícios de expansão populacional, principalmente nas áreas com maior grau de urbanização. A intensificação dos processos decorrentes da urbanização tem como causa a diminuição dos espaços verdes encontrados nas cidades, de modo a contribuir para a elevação da temperatura e, consequentemente, favorecer a proliferação do Ae. aegypti. Adicionalmente, a perda destes espaços implica no processo de homogeneização biótica, fenômeno que atua como adjuvante a plasticidade ecológica do vetor, de maneira a beneficia-lo. Hipótese, corroborada pela sua expansão populacional, exibida principalmente nos ambientes mais antropizados. A estruturação observada nas populações de Ae. aegypti no presente estudo indica que os processos de urbanização desempenham um importante papel na sua conformação, e fatores como o moderado fluxo gênico e déficit de heterozigosidade podem estar refletindo nos seus padrões epidemiológicos / Aedes aegypti is recognized as the main vector of Dengue, in addition to transmit other arboviruses of medical importance, as the agents of Yellow Fever, Chikungunya and Zika. The ecology of this vector is closely associated with the human, being probably the only kind of mosquito to be able to complete all their life cycle inside the human habitations, with their population dynamics strongly related to processes arising from urbanization. Like other cities, the city of São Paulo suffers from environmental stress due to the high population density and unplanned urbanization, which contributes to the proliferation of Ae. aegypti mosquitoes and consequently the increase in the number of cases of dengue fever. Although vaccines such as Yellow Fever and Dengue have already been developed, the latter, more recently, and not yet used on a large scale, vector control remains the main strategy for the disruption of epidemiological patterns of arboviral diseases caused by their pathogens. Structure of the population, is generally the result of combinations resulting from historical and contemporary processes involving certain species, such as their ability to disperse, copulation pattern, physical and environmental barriers and demographic trends, and to determine the different roles of these processes in structuring the population becomes very useful for the medical importance of vector control. A good example is the spread of insecticide resistance, due to gene flow between populations. Therefore, a better understanding of the population structure of Ae. Aegypti is crucial to support and develop new strategies for control programs. Thus, in order to elucidate its pattern of structuring this study utilized wing geometric morphometric and microsatellite markers, for investigation of 11 Ae. aegypti populations collected in areas with different degrees of urbanization, located in the municipality of São Paulo. The results suggest a pattern of structuring according to the urbanization gradient in which the specimens were collected. The distances of Mahalanobis obtained by wing geometric morphometry, statistically significant in 54 of the 55 tests performed, with populations showing a clear trend of segregation in the Canonical Variables analysis and Neighbor-Joining, both for the populations grouped in the form of their urban strata as per their respective collection locations, while the reclassification of test specimens reached relative degree of recognition accuracy. Microsatellites indicated a low genetic structure (Fst = 0.057), with 93 per cent of their statistically significant values. However, in accordance with the gradient of urbanization of the strata, with moderate gene flow, heterozygosity and evidence of population expansion, especially in the areas with the highest degree of urbanization. The intensification of the processes resulting from urbanization Implies in the reduction of the green spaces found in the cities, in order to contribute to the increase of the temperature and thus the proliferation of the Ae. Aegypti. In addition, the loss of these spaces involves biotic homogenization process, a phenomenon that acts as an adjuvant ecological plasticity of the vector, in order to benefit it. Hypothesis, corroborated by its population expansion, displayed mainly in anthropic environments. The structure observed in populations of Ae. aegypti in this study indicates that the urbanization processes play an important role in their conformation, and factors such as moderate gene flow and deficit of heterozygosity can be reflected in their epidemiological patterns

A presente tese compreende 2 capítulos, dedicados à investigação de complexo de espécie e polimorfismo em Aedes scapularis. No Capítulo 1 foi desenvolvido um resumo técnico dos procedimentos utilizados na análise e montagem dos genes do DNA mitocondrial de 19 indivíduos da espécie Aedes scapularis e de como foi realizada a filtragem do DNA de alguns mosquitos em relação ao DNA amplificado do animal picado. No Capítulo 2 realizamos as análises de complexo de espécies e polimorfismo molecular em Aedes scapularis, com espécimes da Mata Atlântica, Caatinga e Mata Amazônica utilizando os marcadores: Morfometria Geométrica, gene Citocromo Oxidase Subunidade I e análise do DNA mitocondrial completo. Encontramos alto polimorfismo evidenciados por todos os marcadores populacionais nos mosquitos dos diferentes biomas estudados e alta estruturação populacional na análise filogenética dos genes mitocondriais codificadores de proteínas. Obtivemos duas conclusões majoritárias em nosso trabalho: 1) a espécie Aedes scapularis é genética e morfologicamente polimórfica em todos os ambientes estudados 2) Não encontramos evidência de complexo de espécies neste mosquito e então acreditamos que este mosquito trate-se de uma única entidade taxonômica. / The present thesis comprises 2 chapters, dedicated to the investigation of species complex and polymorphism in Aedes scapularis. In Chapter 1 a technical summary of procedures used in the analysis and assembly of mitochondrial DNA genes of 19 individuals of the species Aedes scapularis and how the \"filtering\" of the DNA of some mosquitoes was performed in relation to the amplified DNA of the animal bitten. In Chapter 2 we performed the analyzes of species complex and molecular polymorphism in Aedes scapularis, with Atlantic Forest, Caatinga (Xerophytic sparse tropical scrub) and Amazon Forest specimens using the markers: geometric morphometrics, Cytochrome Oxidase Subunit I gene Whole mitochondrial DNA analysis. We found high polymorphism evidenced for every markers in the mosquitoes of different biomes studied and high population structure in the phylogenetic analysis of the protein-coding mitochondrial genes. We obtained two principal conclusions in our work: 1) the species Aedes scapularis is genetic and morphologically polymorphic in all studied environments 2) We did not find evidence of species complex in this mosquito and therefore we believe that this mosquito is a single taxonomic entity.

A abelha Melipona subnitida, popularmente conhecida como jandaíra, é uma espécie endêmica do nordeste brasileiro, que possui distribuição em uma ampla gama de ambientes bastante diversificados pertencentes, principalmente ao bioma Caatinga. Estas abelhas apresentam grande importância para as populações locais por serem uma das espécies mais viáveis para criação, uma vez que se adaptam melhor às condições adversas do meio e são bastante promissoras quando multiplicadas, apresentando grande potencialidade para produção de mel e pólen, além de sua importância ecológica como polinizador. No entanto, essas abelhas encontram-se atualmente ameaçadas devido, em grande parte, à destruição de seu habitat e de seus ninhos naturais para coleta do mel. Apesar de sua relevância, estudos populacionais de espécies de meliponíneos ainda são muito escassos, assim como a urgência em se compreender a estrutura e a dinâmica de suas populações para o monitoramento e conservação de espécies. Neste contexto, o trabalho teve como objetivo avaliar a variabilidade de M. subnitida em diferentes localidades do nordeste brasileiro através da morfometria geométrica das asas anteriores e sequenciamento de um fragmento do gene mitocondrial COI. Foram coletadas operárias de 95 colônias de Areia Branca RN, Barreirinhas MA, Parnaíba PI, Fortaleza CE, Jandaíra RN e Mossoró RN. Para análise do padrão de venação da asa foram utilizadas aproximadamente 10 operárias por colônia, sendo marcados 11 marcos anatômicos em cada asa. Os resultados demonstraram estruturação dos grupos com separação estatisticamente significativa (<0,0001) exceto entre Areia Branca e Jandaíra. O teste de validação cruzada identificou corretamente 88,89% dos indivíduos dentro de suas respectivas áreas. As análises moleculares identificaram 11 haplótipos e presença de alto número de haplótipos exclusivos. A diversidade nucleotídica () de 0,00543e uma diversidade haplotípica (Hd) de 0,79. Tanto as distâncias morfológicas, como os resultados moleculares indicam que a variabilidade entre as populações amostradas está relacionada tanto ao ambiente em que as amostras foram coletadas como com a distância geográfica entre tais localidades, indicando a existência de ecótipos localmente adaptados. / The Melipona subnitida bee, popularly known as jandaíra, is an endemic species to northeastern Brazil, with a wide geographical distribution. These bees are extremely important for local people, since they are adapted to the adverse environmental conditions, are very promising when multiplied, and present good potential for honey and pollen production, allied to their ecological importance as pollinators. However, these bees are currently largely threatened due to the destruction of their habitat and their natural nests for honey collection. Despite its relevance, population studies of stingless bee species are still very scarce, as well as the urgency in understanding the structure and dynamics of their populations for monitoring and species conservation. In this context, this study aimed to evaluate the variability of M. subinitida in different localities in northeastern Brazil through geometric morphometrics of the forewing and sequencing of COI mitochondrial gene fragment. We collected workers from 95 colonies from Areia Branca RN, Barreirinhas MA, Parnaíba PI, Fortaleza CE, Jandaíra RN and Mossoró RN. To analyze the pattern of wing venation, we used approximately 10 workers per colony, and 11 landmarks were plotted on each wing. The results showed groups structures with separation statistically significant (<0,0001) except between Areia Branca and Jandaíra. The cross-validation test correctly identified 88,89% of individuals within their respective areas. Molecular analysis identified 11 haplotypes and presence of high number of exclusive haplotypes among the populations. The nucleotide diversity () of 0,00543 and haplotype diversity (Hd) of 0,79. Both morphological distances and molecular results indicated that variability among the sampled populations is related both to the environment in which samples were collected as to the geographical distance between these locations, indicating the existence of locally adapted ecotypes.

Neste trabalho foram investigados a distribuição de populações e aspectos populacionais (densidades populacionais e distribuição da classe de tamanho, peso e fator de condição) de bagres Trichomycterus troglóbios, com enfoque na Gruta do Urubu Rei, entre abril de 2010 a outubro de 2012. As prospecções em campo resultaram na confirmação de 11 localidades com ocorrência desses bagres, distribuídas ao longo de 115 km na direção norte-sul ao longo das cabeceiras cársticas do Rio Miranda, quatro delas tratando-se de novos registros. A densidade da população de Trichomycterus sp. 1 na Gruta do Urubu Rei está sujeita às variações sazonais entre anos relacionadas aos ciclos pluviométricos regionais. O predomínio de classes de tamanhos juvenis (CP < 40 mm), os deslocamentos relativamente grandes de indivíduos maduros, as variações na densidade populacional indicam que a Gruta do Urubu Rei abriga uma população aberta e possui condições ambientais propícias à reprodução e crescimento, funcionando como uma caverna \"berçário\".As comparações dos parâmetros estudados sugerem que as populações-fontes de Trichomycterus sp. 1 ocupam ambientes freáticos próximos à superfície, possivelmente devido à maior disponibilidade alimentar nestes locais. Por outro lado, os dados de densidade populacional e de distribuição das classes de tamanho indicam que T. Dali e Trichomycterus sp. 2 possivelmente habitam ambientes freáticos profundos e reproduzem-se próximo à superfície. Até o momento, pouco se sabe sobre a ecologia destas espécies em cavernas subaquáticas da região, fazendo-se necessários estudos futuros para compreender a dinâmica das populações no freático profundo. Os bagres Trichomycterus subterrâneos da Serra da Bodoquena devem ser considerados vulneráveis à extinção, pois seus hábitats estão sugeitos à degradação antrópica, como a contaminação e explotação da água subterrânea, assoreamento do aquífero de condutos e o turismo não-controlado. Entre as populações troglóbias de bagres Trichomycterus na Serra da Bodoquena, foram identificadas três linhagens divergentes através do uso de duas técnicas complementares e independentes, a análise de sequências de nucleotídeos do DNA mitocondrial e a morfometria geométrica. As genealogias obtidas para os genes COI, Cit b e 16S foram concordantes, apresentando o mesmo padrão de distribuição geográfica. A divergência genética não está correlacionada com a distância geográfica, sendo melhor explicada pela presença dos haplogrupos. Foi detectado um alto grau de isolamento populacional e baixa variação genética intrapopulacional. Este resultado pode ser explicado pela compartimentação do hábitat, devido ao predomínio de bacias poligonais ao longo do Planalto da Bodoquena, limitando do fluxo gênico entre as populações. Na Gruta Morro do Jericó foi detectada a ocorrência sintópica dos haplogrupos I e II, o que explica o alto valor de divergência nesta localidade. Possivelmente, essa é uma zona secundária de contato entre T. Dali e TB.sp. 1. A presença de fluxo de água subterrânea com rotas profundas no Setor sul, pode explicar o menor grau de divergência genética e morfológica entre T. dali e Trichomycterus sp. 2. A forma corporal indica diferentes graus de especialização, possivelmente associados às diferentes condições ambientais entre os sistemas cársticos da área de estudo. A presença da linhagem mais troglomórfica ao sul da Serra da Bodoquena, região onde ocorrem cavernas atualmente alagadas depois de uma fase vadosa, sugere que o isolamento das linhagens troglóbias de Trichomycterus esteja associado ao soerguimento relativo, resultante da subsidência da Bacia do Pantanal e responsável pela geomorfologia atual da região. É hipotetizado que o isolamento dos Trichomycterus no subterrâneo tenha ocorrido na segunda metade do Terciário, quando o soerguimento relativo do Planalto da Boquena foi acelerado / The present study focused the distribution of Trichomycterus populations and populational aspects (population density and distribution of size, weight and condition factor classes), in the Urubu Rei Cave, between April 2010 andOctober 2012. Field surveys confirmed the occurrence of Trichomycterus catfishes in 11 localities, included four new records, distributed along 115 km in the north-south direction encompassing the karst headwaters of the Miranda River basin,. The population density of Trichomycterus sp. 1 in the Urubu Rei Cave showed seasonal and inter-years variations related to regional pluviometric cycles. The predominance of juvenile size classes (SL < 40 mm), the relatively long-distance moviments of mature individuals and variations in population densities indicate that Urubu Rei Cave shelters an open population whith environmental conditions favorable for reproduction and growth. The comparisons of parameters indicate that the source populations of Trichomycterus sp. 1 occupy groundwater habitats near the surface, possibly due to greater food availability in this zone. On the other hand, data on population density and distribution of size classes suggest that T. Dali and Trichomycterus sp. 2 probably inhabit deep phreatic habitats and reproduce near the surface so far. Little is known about the ecology of these species in underwater caves hence further studies are necessary to understand the population dynamics in the deep phreatic zone. Subterranean Trichomycterus catfish from Serra da Bodoquena shoul be considered at least vulnerable, because their habitats are subjected to anthropogenic degradation, such as exploitation and contamination of groundwaters and sedimentation conduits aquifer and poorly controlled touristic visitation. Among troglobitic populations of Trichomycterus catfishes in Serra Bodoquena kart area, three lineages were identified using of two independent and complementary methods, the analysis of nucleotide sequences of mitochondrial DNA and geometric morphometric. The genealogies obtained for COI, Cyt b and 16S were highly concordant and showeded the same pattern of geographic distribution. The genetic divergence was not correlated with the geographic distance and was best explained by the presence of haplogroups. A high degree of population isolation was detected, with low intra-population genetic variation. The limited gene flow may be explained due to the partitioning of the habitat by the predominance of polygonal basins along the Bodoquena Plateau. In the Cave Morro do Jericó the sintopy of haplogroups I and II, with a high value of divergence in this locality, indicate the presence of a secondary contact zone between T. Dali and Trichomycterus sp. 1. The presence of deep routes of groundwater flow in the South Sector of the Bodoquena Plateau, may explain the lower degree of genetic and morphological divergence between T. Dali and Trichomycterus sp. 2. The comparisons of body shape indicates different degrees of specialization, possibly related to different environmental conditions among the karst in the region. Highly troglomorphic lineages occur in southern Serra Bodoquena, where the presence currently flooded caves after a vadose phase, indicates that the isolation of ancient Trichomycterus lineages in subterranean habitats is associated with relative uplift of the region. This would be the result of the subsidence the Pantanal Basin, that is the process responsible by the current geomorphology of the region. We estimated that the underground isolation occurred during the second half of the Tertiary, when the relative uplift of the Bodoquena Plateau was accelerated

<p>The PhD research project focus on the study of evolution, adaptation, and speciation in<br />the subterranean environment using troglobitic Coleoptera of the genus Anthroherpon<br />as a model organism. Genus Anthroherpon belongs to the tribe Leptodirini (Coleoptera:<br />Leiodidae: Cholevinae), a group that has undergone extensive diversification in the<br />subterranean environment. All species of this genus have developed typical<br />troglomorphic modifications: complete anophthalmy, apterism, extreme elongation of<br />appendages, head, and pronotum, and physogastric elytra. To understand the<br />evolutionary history of this group, the troglomorphic adaptations need to be studied in<br />a phylogenetic framework. The thesis provide a comprehensive evolutionary analysis<br />of the Anthroherpon radiation, using a dated molecular phylogeny as a framework for<br />understanding Anthroherpon diversification, reconstructing the ancestral range, and<br />exploring troglomorphic diversity. In light of these findings, a new taxonomical<br />organisation of the group has been proposed.</p> / <p>Doktorska disertacija predstavlja studiju evolucije, adaptacije i specijacije u<br />podzemnim stani&scaron;tima troglobiontnih tvrdokrilaca roda <em>Anthroherpon</em>. Pomenuti rod<br />pripada tribusu Leptodirini (Leiodidae, Cholevinae), grupi koja je pro&scaron;la intenzivnu<br />diverzifikaciju u uslovima podzemnih stani&scaron;ta. Sve vrste pomenutog roda poseduju<br />tipične troglomorfne osobine, kao &scaron;to su: anoftalmija, apterizam, ekstremno izduženi<br />telesni nastavci, glava i pronotum, i fizogastrija. Radi razumevanja evolucione istorije<br />grupe, troglomorfne adaptacije su studirane u filogenetskom kontekstu. U analizi<br />evolutivne radijacije roda <em>Anthroherpon</em> kori&scaron;ćena je datirana molekularna filogenija<br />kao okvir za razumevanje diverzifikacije roda, evolucije troglomorfnih karaktera i<br />rekonstrukciju predačkog areala. U svetlu novih nalaza predložena je nova<br />taksonomska organizacija grupe.</p>

Late Pleistocene American black bears (Ursus americanus) often overlap in size with Pleistocene brown bears (U. arctos), occasionally making them difficult to diagnose. Large U. americanus have previously been distinguished from U. arctos by the length of the upper second molar (M2). However, the teeth of fossil U. americanus sometimes overlap size with U. arctos. As such, there is need for a more accurate tool to distinguish the two species. Here, 2D geometric morphometrics is applied to the occlusal surface of the M2 to further assess the utility of this tooth for distinguishing U. americanus and U. arctos specimens. When combined with an Ecological Niche Model of U. americanus and U. arctos in North America from the Last Glacial Maximum, this morphometric technique can be applied to key regions. A case of two Pleistocene specimens previously identified as U. arctos from eastern North America exemplifies the utility of this combination.

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.