A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, March 2016. / Environmental temperature greatly affects many aspects of an ectotherm’s physiology. These effects can be so significant that temperature is often the foremost constraint determining an ectotherm’s distribution. However, establishing the link between these mechanistic limitations and distribution require often-intensive and costly investigations. In an attempt to improve efficiency and reduce cost, niche-based models are often implemented as a means to identify potential constraints. However, these approaches are mere hypotheses-generators, and do not directly establish causal links between geographic range and limiting factors. Furthermore, the mismatch of species-appropriate scale and resolution of input data are often not addressed in these models. This dissertation directly examined the relationship between a southern African skink, the Rainbow Skink (Trachylepis margaritifer) and environmental temperatures. It examined the effect of temperature on appetite, digestive efficiency, and gut transport times. It assessed the potential for this species to serve as a candidate for stress metabolite studies and evaluated how accurately a niche model predicted the environmental temperatures experienced at a fine-scale (i.e., speciesappropriate, microhabitat resolution) based on broad-scale temperature inputs. Additionally, the suitability of habitat quality proxies are assessed against both model predictions and on-the-ground measures made at a fine scale. Temperature significantly affected appetite, with low temperatures (25 °C) resulting in decreased appetite. Gut transit times are also significantly affected, but not in an expected pattern. At low temperatures (25 °C), gut transit time was decreased when compared to those recorded at an intermediate temperature (27 °C). Transit times however remained predictably low at high temperatures (32 °C). However, this unusual pattern in transit times had no effect on associated digestive efficiencies. Instead, digestive efficiencies remained equally high across these three temperatures tested. Additionally, habitat quality proxy measures in general aligned poorly to modeled predictions. No meaningful differences in habitat quality were found using typical thermal assessments of environmental means, but were when using skink-relevant and biologically meaningful ones. For T. margaritifer, continuous exposure to 22 °C impairs digestion and promotes skin lesions and eventual death under controlled conditions, and at sites where exposure to 22 °C were greatest, skinks appeared to be in the poorest condition, and many exhibited skin lesions. These findings strongly suggest that 22 °C may represent a lower thermal constraint for the species, and highlights the importance of mechanistic studies that directly investigate factors affecting a species’ physiological performance. In addition, techniques such as measuring glucocorticoids and their metabolites may better reflect habitat quality, as well as serving to validate selected habitat quality proxies. Overall, despite the everincreasing approaches available to conservationists and ecologists alike, this work emphasizes that if we are to take full advantage of these new techniques, in-depth, trait-specific mechanistic studies must maintain their place among them. / MT2016

Thesis (Ph. D.)--Brigham Young University. Dept. of Integrative Biology, 2004. / Includes bibliographical references (p. 75-80).

Submitted by Fernanda Rodrigues de Lima (fernanda.rlima@ufpe.br) on 2018-08-16T22:53:52Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Arthur do Nascimento Cabral.pdf: 3365751 bytes, checksum: 976e5152fbbcd8fa55f5f64eba574253 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-08-27T22:30:01Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Arthur do Nascimento Cabral.pdf: 3365751 bytes, checksum: 976e5152fbbcd8fa55f5f64eba574253 (MD5) / Made available in DSpace on 2018-08-27T22:30:01Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Arthur do Nascimento Cabral.pdf: 3365751 bytes, checksum: 976e5152fbbcd8fa55f5f64eba574253 (MD5) Previous issue date: 2017-06-20 / CAPES / O presente estudo objetivou investigar aspectos helmintológicos deMabuya arajara, bem como avaliar a relação do ciclo testicular da espécie com o desenvolvimento do segmento sexual renal(SSR) e a sazonalidade ambiental. Realizamos coletas bimensais(setembro 2009/julho 2010) na Chapada do Araripe, Nordeste do Brasil. Imediatamente após as coletas, todos os lagartos foram pesados, mensurados quanto ao comprimento rostro-cloacal (CRC) e eutanasiados. Parasitologicamente, após análises do trato digestivo deM. arajara, os helmintos foram clareados com lactofenol eidentificados com a utilização de microscópio deluz. Ao todo, 56%dos lagartos examinados foram infectados por quatro espécies de nematodes: Physalopteroidesvenancioi, Physalopterasp., Strongyluris oscarie Parapharyngodon alvarengai, sendo esta última espécie amais expressiva(prevalência de53.5%; intensidade de infecção 3,37 +2,0; índicedediscrepância0,69). Parapharyngodon alvarengai atuou constantemente no intestino de M. arajaraao longo do ano,estando suas maiores taxas de infecção associadas ao mês de julho e com extensão por toda estação seca da região. Além disso, lagartos de maiores CRC e CRC/massa foram mais infectados frente aos demais. Por outro lado, as relações entre abundância parasitária/massa e entre os sexos não foram significativas. Portanto, classificamos M.arajara como um novo hospedeiro para os nematodes descritos. Considerando aspectos reprodutivos, rins e testículos dos espécimes foram submetidos a tratamentos histológicos. Realizamos colorações com Hematoxilina e Eosina, Ácido Periódico Reativo de Schiff(PAS) e Azul de Alcian (AA)para avaliação geral do tecido, detecção de polissacarídeos neutros e ácidos, respectivamente. O pico reprodutivo foi refletido pela máxima espermatogênese durante a estação seca da região. Citologicamente, os túbulos seminíferos foram preenchidos por espermatozoides e células germinativas em diferenciação. O SSR consistiu em um epitélio colunar alto, núcleos basais e conteúdo de secreção eosinófilo ePAS+que preencheu todo o citoplasma das células. A estação chuvosa marcou o estado de inatividade reprodutiva pela não produção de espermatozoides. Em sincronia, o SSR foi formado por um epitélio cúbico e ausência ou pequena quantidade de material de secreção AA+. A reprodução de M. arajara é sazonal e, assim como os dados parasitológicos mostraram, a estação seca da região atuou no ajuste da espermatogênesee da ação suplementar do SSR. Sugerimos, portanto, que uma possível elevação dos níveis de testosterona neste período, responsável pelo desencadeamento da atividade reprodutiva da espécie, contribua para a susceptibilidade à infecção parasitária. / The present study aimed to investigate helminthological aspects of Mabuya arajara, and evaluate the relationship between testicular cycleof the species with the development of renal sexual segment (RSS) and environmental seasonality. Bi-monthly field sampling were conducted (September 2009/ July2010)in Chapada do Araripe, north eastern Brazil. Immediately after collected, all lizards were weighed, snout-vent length (SVL)was measured and euthanized. For parasitology, after analysis of the digestive tract of M. arajara, helminthes were cleared with lacto phenol and identified using light microscopy. As result,56%ofexamined lizards were infected by four species of nematodes: Physalopteroides venancioi, Physaloptera sp., Strongyluris oscariand Parapharyngodon alvarengai, with this last species the most expressive(prevalenceof53.5%; mean infection intensityof3.37 +2.0; discrepancyindexof0.69). Parapharyngodonalvarengaiwas present in the intestine of M. arajara throughout the year, being its highest rate of infection related to the month of July and extending during the dry season of the region. In addition, lizards of larger SVLand SVL/mass were more infected compared to the others. However, the relationships between parasite abundance/mass and between sexes were not significant. Therefore, we classified M. arajara as a new host for the nematodes here identified. Concerning reproductive aspects, kidneys and testicles were submitted to conventional histological processes. We performed colorations with hematoxylin and eosin, Periodic Reactive Acid of Schiff(PAS) and Alcian blue for general tissue evaluation, neutral and acid polysaccharides detection, respectively. Thereproductivepeak was reflected by the maximum spermatogenesis during the dry season. Cytologically, the seminiferous tubules were completed by spermatozoids and germ cells in differentiation. The renal sexual segment(RSS)consisted of a high columnar epithelium, with nuclei located basally and secretion of eosinophilic granules filling the cytoplasm of epithelial cells, it also showed a strong positive reaction PAS+.The rainy season marked the state of reproductive inactivity by the non-production of spermatozoids. In synchrony, the SSR was formed by cubic epithelium and the absence or low quantity of secretion content of AA+. The reproduction of M. arajara is a seasonal and, as indicated by the parasitological data, the dry season seems to influence the spermatogenesis and supplementary action of RSS. We suggest, therefore, that a possible elevation of testosterone levels in this period, responsible for triggering of the reproductive activity of the species, contributes to the susceptibility to parasitic infection.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-02T14:38:20Z No. of bitstreams: 1 paolarosadeoliveira.pdf: 7165784 bytes, checksum: b8993af050b9951236c8dab6f615b61a (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-06T12:14:05Z (GMT) No. of bitstreams: 1 paolarosadeoliveira.pdf: 7165784 bytes, checksum: b8993af050b9951236c8dab6f615b61a (MD5) / Made available in DSpace on 2017-06-06T12:14:05Z (GMT). No. of bitstreams: 1 paolarosadeoliveira.pdf: 7165784 bytes, checksum: b8993af050b9951236c8dab6f615b61a (MD5) Previous issue date: 2017-02-22 / Dentre os estudos sobre características reprodutivas de lagartos, muitos são realizados com espécies de regiões temperadas. Diferentes fatores podem influenciar no ciclo reprodutivo das espécies de lagartos neotropicais como umidade, temperatura e pluviosidade, sendo este último determinante em regiões tropicais. Estudos sobre a biologia reprodutiva de lagartos do gênero Mabuya revelaram características peculiares da reprodução e da história de vida; com isso pode ser considerado um táxon modelo para estudos sobre a evolução dos padrões reprodutivos em vertebrados. As espécies Notomabuya frenata e Aspronema dorsivittatum, apesar de apresentarem alguns aspectos reprodutivos conhecidos, muitas de suas características ainda são desconhecidas. Nesse contexto, o objetivo do presente estudo foi caracterizar morfohistologicamente o segmento sexual renal (SSR) e a espermatogênese de N. frenata e A. dorsivittatum. Os espécimes utilizados neste estudo foram coletados em uma área do bioma Cerrado no estado de Minas Gerais, Brasil. Os rins foram analisados através de microscopia de luz e eletrônica de varredura; e os testículos apenas com microscopia de luz. Ao analisar os rins, constatou-se a presença do SSR apenas em machos sexualmente maduros. O SSR se apresentou revestido por células colunares altas, com núcleo basal e a porção apical repleta de grânulos secretores; tais características morfo-histológicas observadas em ambas as espécies são similares as observadas em outros estudos com diferentes espécies de Squamata. Os testículos foram processados de acordo com técnicas de histologia convencional e analisados por microscopia de luz. Todos os espécimes machos adultos analisados estavam em período reprodutivo, pois apresentavam espermatozoides nos testículos e/ou epidídimos. O epitélio germinativo de ambas as espécies era composto por células germinativas e células de Sertoli, x apresentando um ciclo reprodutivo contínuo. O epidídimo das espécies estudadas apresentouse revestido por epitélio colunar simples, com células altas, núcleos basais e o lúmen completamente preenchido por espermatozoides. Os espécimes de N. frenata e A. dorsivittatum analisadas apresentaram o epitélio germinativo organizado de forma similar a outros Squamatas anteriormente estudados. Existem poucos estudos que abordem a descrição morfo-histológica do segmento sexual renal, células germinativas e espermatogênese de lagartos brasileiros. Dessa forma, o presente estudo acrescenta, não somente o conhecimento sobre a biologia reprodutiva nessas espécies, mas auxilia numa maior compreensão sobre estratégia e biologia reprodutivas em espécies vivíparas e neotropicais. / Among the studies on the reproductive characteristics of lizards, many are carried out with species of temperate regions. Different factors may influence the reproductive cycle of neotropical lizard species such as humidity, temperature and rainfall, being the latter determinant in tropical regions. Studies on the reproductive biology of lizards of the genus Mabuya revealed peculiar characteristics of the reproduction and the history of life; with this it can be considered a model taxon for studies on the evolution of the reproductive patterns in vertebrates. The species Notomabuya frenata and Aspronema dorsivittatum, although presenting some known reproductive aspects, many of its characteristics are still unknown. In this context, the objective of the present study was to characterize the morphologically the sexual segment of the kidney (SSK) and the spermatogenesis of N. frenata and A. dorsivittatum. The specimens used in this study were collected in an area of the Cerrado biome in the state of Minas Gerais, Brazil. The kidneys were analyzed by light microscopy and scanning electron microscopy; and the testis only with light microscopy. When analyzing the kidneys, the presence of SSK was only found in sexually mature males. The SSK was coated by high columnar cells with basal nucleus and the apical portion filled with secretory granules; Such morpho-histological characteristics observed in both species are similar to those observed in other studies with different Squamata species. The testes were processed according to standard histology techniques and analyzed by light microscopy. All the adult male specimens analyzed were in the reproductive period, as they had spermatozoa in the testis and / or epididymis. The germinal epithelium of both species was composed of germ cells and Sertoli cells, presenting a continuous reproductive cycle. The epididymis of the species studied was coated by simple xii columnar epithelium, with high cells, basal nucleus and the lumen completely filled by spermatozoa. The specimens of N. frenata and A. dorsivittatum analyzed presented the germinative epithelium organized in a similar way to other Squamata previously studied. There are few studies that address the morpho-histological description of the renal sexual segment, germ cells and spermatogenesis of Brazilian lizards. Thus, the present study not only adds knowledge about reproductive biology in these species, but also aids in a better understanding of reproductive strategy and biology in viviparous and neotropical species.

Scincidae (skinks) comprise one of the largest families of lizards, and the more than 1300 species show great variation in body size and form, and are found worldwide in a diversity of habitats. The group presents many interesting questions ranging from the colonization of oceanic islands, to the evolution of limb loss, yet most of these and other questions remain understudied. The purpose of this dissertation is to use multiple mitochonidrial and nuclear DNA markers in connection with current cladistic methods to address evolutionary questions at many levels within Scincidae. In chapter one, a molecular phylogenetic study, based on six genes and extensive analyses support Cordylidae+Xantusiidae as its sister group, and confirm the paraphyly of Scincinae. The Acontinae is the sister group to all remaining skinks, while Feylininae is nested within an otherwise monophyletic southern African scincine clade. Limited support for reversal of limb and digit loss is found. In chapter two, the monophyly and relationships of Malagasy scincines are investigated using data from seven gene regions. Malagasy scincines are monophyletic, and derived from a single colonization from southern Africa. Our analyses confirm the paraphyly of Amphiglossus, and support Madascincus as a valid genus. Madascincus is sister to a monophyletic Paracontias, while Voeltzkowia is basal to the remaining Amphiglossus and Pygomeles. Chapter three uses seven gene regions to infer relationships within South American Mabuya, and to test the hypothesis of two independent colonizations from Africa to the New World. Direct Optimization (DO) is compared with traditional alignment methods, and multilocus maximum likelihood and Bayesian methods are used to date divergence times within the group. Results show that DO consistently finds more optimal tree topologies regardless of the optimality criterion used, and provides the ability to use models throughout the alignment and tree reconstruction process. South American Mabuya are not monophyletic, and the two colonization hypothesis is confirmed with parametric bootstrapping. Within the mainland species of Mabuya, many taxonomic problems are uncovered including multiple species complexes. Due to the lack of reliable fossil information, dating methods differ greatly in their estimates of divergence dates within Mabuya.

Submitted by Edisangela Bastos (edisangela@ufpa.br) on 2013-08-23T15:25:20Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseMorfometricaCinco.pdf: 3667781 bytes, checksum: e0a243e29642cbf6463847f39c85cacb (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2013-08-26T15:38:33Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseMorfometricaCinco.pdf: 3667781 bytes, checksum: e0a243e29642cbf6463847f39c85cacb (MD5) / Made available in DSpace on 2013-08-26T15:38:33Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseMorfometricaCinco.pdf: 3667781 bytes, checksum: e0a243e29642cbf6463847f39c85cacb (MD5) Previous issue date: 2002 / O presente trabalho tem como objetivo analisar a variação da forma do corpo ao longo da ontogenia em Mabuya agilis Boulenger, 1887; M. bistriata (Spix, 1825); M. guaporicola Dunn, 1936; M. macrorkyncha Hoge, 1946 e M. nigropunctata (Spix, 1825), espécies sul-americana de lagartos, buscando definir as diferenças interespecíficas em termos de suas proporções corporais, qual o papel de um possível crescimento alométrico no desenvolvimento da forma adulta de cada espécie, e se as diferenças observadas poderiam estar associadas às diferenças nos hábitats ocupados por cada espécie. Para isso foi utilizado a análise de componentes principais (PCA), para estimar tanto as trajetórias ontogenéticas como o crescimento alométrico de cada espécie. Dados sobre os hábitats ocupados por cada espécie foram compilados da literatura. A inclinação da reta indicando a trajetória ontogenética foi significativamente diferente entre Mabuya guaporicola e todas as demais espécies, e entre M. bistriata e M. nigropunctata. A análise dos coeficientes alométricos permitiram constatar que: a redução relativa dos membros, associado com um alongamento do corpo em Mabuya guaporicola, foi alcançada através da redução das mãos, pés e, especialmente, dos dígitos; em M. agi/is houve um alongamento do corpo; M. macrorhyncha apresentou a região da cintura escapular robusta, especialmente alta, e as mãos com uma redução acentuada; em M. bistriata os braços são relativamente curtos e coxa e tíbia alongados; e M. nigmpunctata, comparado com as demais espécies estudadas, foi a espécie cuja forma do corpo menos se alterou ao longo do crescimento. Através desses resultados, juntamente com os dados obtidos da literatura sobre o hábitat ocupado por cada espécie estudada, foi concluído que algumas especializações morfológicas encontradas poderiam ser explicadas como adaptações funcionais ao uso de seus hábitats. / The present study has as its main objective to analyse the ontogenetic variation of body shape in the South American skinks Mabuya agi/is Boulenger, 1887; M. bistriata (Spix, 1825); M. guaporicola Dunn, 1936; M. rnacrorhyncha Hoge, 1946 and M. nigropunctata (Spix, 1825). Interspecific differences of body proportions as a possible result of allometric growth in these species are also examined. PCA analysis was used for estimate the both ontogenetic trends and allometric growth. Ontogenetic trend lines were significantly different between M. guaporicola and the others species, and between M. bistriata and M. nigropunctata. Ali of the other pairs showed significantly different Y intercept between each other. Analysis of the allometric coefficients indicates that relative reduction of limbs associated with body elongation in Mabuya guaporicola are due to the reduction of its hands, feet and specially digits; M. rnacrorhyncha presents a high and stout pectoral girdle and its hands show an accentuated reduction; in M. bistriata, its arms are relatively short and its thigh and tibia elongate. M. nigropunctata is the species which the least modified body shape during ontogeny. The association of these results with data on habitats utilized by each species (obtained from the literature) indicates that some morphological specializations found in each species could be explained as functional adaptations to their habitats.