Thesis--University of Michigan. / Without thesis statement. Bibliography: p. 250-266.

No description available.

Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The Afroedura nivaria complex is one of the six recognized species complexes within a southern African endemic genus, Afroedura. The A. nivaria complex is a morphologically conservative group of medium-sized geckos endemic to South Africa though they are unevenly distributed in the Eastern Cape, Free State and KwaZulu-Natal provinces. The complex comprises the following five species: A. nivaria (Boulenger 1894), A. amatolica (Hewitt 1925), A. karroica (Hewitt 1925), A. tembulica (Hewitt 1926) and A. halli (Hewitt 1935). These nocturnal and rupicolous geckos shelter in narrow rock crevices on outcrops. It is currently unknown whether a) the described species are valid and b) if additional lineages are present on isolated outcrops. I investigated the hypothesis that endemics with a narrow distribution, that is, A. amatolica and A. tembulica are valid species but that isolated populations in the widespread species (A. nivaria, A. karroica and A. halli) demonstrate genetic variation at the species level. Fragments of two mitochondrial genes (16S rRNA and ND4) and a single nuclear marker (KIAA) were sequenced and analysed using Bayesian inference, maximum parsimony and maximum likelihood. All analyses strongly supported the genetic distinctiveness of the described species. The A. nivaria complex is not monophyletic, A. karroica appeared to be outside the species complex and A. pondolia (thought to be outside the A. nivaria complex) consistently nested within A. nivaria complex. Additional clades recovered in the phylogeny within A. halli and A. nivaria had large genetic divergences and no spatial overlap. Narrowly distributed A. amatolica showed to have two highly diverged clades. Clades recovered in the phylogeny highlight geographical structuring. These findings suggest the existence of up to four additional cryptic lineages within the complex. I used morphometric data (ecologically relevant morphological traits) to investigate whether the genetic lineages would present morphological conservatism. Multivariate analyses of 19 variables showed variation within the A. nivaria species complex was accounted for mostly by differences in locomotor apparatus (limbs and feet) and head dimensions. These traits are mostly related to microhabitat usage and/or dietary specialization in lizards. There were no significant differences for body dimensions between species within the complex, indicative of morphological conservatism. It appears genetic divergence has been achieved among the different clades within A. nivaria complex, but with much similarity in phenotype being retained because of fragmented but similar habitats occupied. / AFRIKAANSE OPSOMMING: Die Afroedura nivaria kompleks is een van ses herkende spesies komplekse binne die endemiese suidelike Afrika genus, Afroedura. Die A. nivaria kompleks is ‘n morfologiese konserwatiewe groep bestaande uit medium grootte geitjies endemies tot Suid Afrika, alhoewel hulle oneweredig verspreid is in die Oos Kaap, Vrystaat en Kwazulu-Natal provinsies. Die kompleks bestaan uit die volgende vyf spesies: A. nivaria (Boulenger 1894), A. amatolica (Hewitt 1925), A. karroica (Hewitt 1925), A. tembulica (Hewitt 1926) and A. halli (Hewitt 1935). Hierdie geitjies kom snags voor en skuil tussen nou skeure op klip koppies. Dit is tans onbekend of a) die beskryfde spesies geldig is en b) of die addisionele afstammelinge voorkom op geisoleerde koppies. Met die studie het ek die hipotese ondersoek dat endemiese spesies met ‘n noue verspreiding (A. amatolica en A. tembulica) geldige spesies is, maar dat spesies met ‘n wye verspreiding (A. nivaria, A. karroica and A. halli) genetiese variasie op spesie vlak wys. Fragmente van twee mitochondriale gene (16S rRNA and ND4) en ‘n enkele nuklêre merker (KIAA) se basispaaropeenvolgingsdata was verkry en geanaliseer deur Bayesian inferensie, maksimum parsimonie en maksimum waarskynlikheid. Alle analise het die genetiese kenmerkendheid van die beskryfde spesies sterk ondersteun. Die A. nivaria kompleks is monofileties, A. karroica het geblyk om buite die spesies kompleks voor te kom en A. pondolia (voorheen beskryf as buite die A. nivaria kompleks) het voortdurend binne die A. nivaria kompleks voorgekom. Addisionele klades afkomstig vanaf die filogenië van A. halli en A. nivaria het vir beide spesies groot genetiese divergensie met geen ruimtelike oorvleuling gewys. Afroedura amatolica, met sy noue verspreiding, het twee hoogs divergente klades getoon. Die klades onthul deur die filogenie beklemtoon ‘n geografiese struktuur. Hierdie bevindings blyk die bestaan van tot vier ekstra kriptiese afstammelinge binne die kompleks. Ek het morfometriese data (ekologiese relevante morfologiese eienskappe) gebruik om vas te stel of die genetiese afstammelinge morphologies konserwatief sal wees. Meerveranderlike analises op 19 veranderlikes het variasie binne die A. nivaria spesies kompleks getoon. Hierdie veranderinge was meestal gevind in die beweeglikheidsapparatuur (ledemate en voete) en kop dimensies. Die verskeie eienskappe hou meestal verband met die mikrohabitatte wat gebruik word en/of dieët spesialisering in akkedisse. Daar was geen noemenswaardige verskille in liggaamsdimensies tussen spesies in die kompleks nie, beduidend op ‘n konserwatiewe morfologie. Dit wil blyk of genetiese divergensie tussen die verskeie klades van die A. nivaria kompleks bewerkstellig is met ooreenstemming in die fenotipes as gevolg van gefragmenteerde maar soortgelyke habitat verbruik.

BACKGROUND:The extant squamates (>9400 known species of lizards and snakes) are one of the most diverse and conspicuous radiations of terrestrial vertebrates, but no studies have attempted to reconstruct a phylogeny for the group with large-scale taxon sampling. Such an estimate is invaluable for comparative evolutionary studies, and to address their classification. Here, we present the first large-scale phylogenetic estimate for Squamata.RESULTS:The estimated phylogeny contains 4161 species, representing all currently recognized families and subfamilies. The analysis is based on up to 12896 base pairs of sequence data per species (average = 2497 bp) from 12 genes, including seven nuclear loci (BDNF, c-mos, NT3, PDC, R35, RAG-1, and RAG-2), and five mitochondrial genes (12S, 16S, cytochrome b, ND2, and ND4). The tree provides important confirmation for recent estimates of higher-level squamate phylogeny based on molecular data (but with more limited taxon sampling), estimates that are very different from previous morphology-based hypotheses. The tree also includes many relationships that differ from previous molecular estimates and many that differ from traditional taxonomy.CONCLUSIONS:We present a new large-scale phylogeny of squamate reptiles that should be a valuable resource for future comparative studies. We also present a revised classification of squamates at the family and subfamily level to bring the taxonomy more in line with the new phylogenetic hypothesis. This classification includes new, resurrected, and modified subfamilies within gymnophthalmid and scincid lizards, and boid, colubrid, and lamprophiid snakes.

I conducted an integrative field study on male cottonmouths (Agkistrodon piscivorus), a common pitviper of the southeastern United States, to investigate the evolution of contrasting mating patterns in North American pitvipers (bimodal and unimodal annual patterns) and resolve conflicting information about the pattern exhibited by the cottonmouth. I determined a unimodal late summer peak of testosterone (T) and a muted unimodal seasonal cycle of the sexual segment of the kidney (a secondary sexual characteristic), both of which were correlated with the single peak of spermatogenesis in late summer. I also conducted a study to determine diel and seasonal variation of corticosterone (CORT), the effect of captive handling on CORT, and the relationship between CORT and T after captive handling, and detected a significant elevation of CORT and a significant decrease of T after capture in male cottonmouths, as well as a significant negative correlation between CORT and T.

No description available.

Multicomponent signals are complex stimuli directed to receptors of only single modality. Colourful ornaments of animals are multicomponent signals. In this thesis I present results of studies on the origin of coloration in turtles and squamate reptiles together with notes on relativistic view of the functionality of animal coloration. The results show that turtle coloration, which have been studied only marginally until now, is shaped by sexual selection. It is shown that turtles share mechanisms of coloration by vertical organization of different pigment cell types together with squamate reptiles. Turtles also produce colour by organization of collagen fibres which share trait with birds and mammals. Mechanisms of body coloration differ dramatically between closely related turtle species studied even though the individual constituting components are shared among these species. On the example of polymorphic lizards, it is shown that qualitative categorical difference between groups of individuals of the same population are maintained based on quantitative changes in pigment contents regulated by ancient loci shared by different species. The turtles and reptiles are valuable source of our knowledge on the evolution of multicomponent visual signalling due to their intriguing composition of skin....

The extant venomous Gila monster and beaded lizards, species of Heloderma, live today in southwestern USA and south along the Pacific coastal region into Central America, but their fossil history is poorly understood. Here we report helodermatid osteoderms (dermal ossicles) from the late Miocene-early Pliocene Gray Fossil Site, eastern Tennessee USA. Twenty-three species of mammals are known from the fauna including abundant Tapirus polkensis, as well as fishes, anurans, salamanders, turtles, Alligator, birds, and snakes. Beaded lizards belong to the Monstersauria, a clade that includes Primaderma + Paraderma + Gobiderma + Helodermatidae (Estesia, Eurheloderma, Lowesaurus, and Heloderma). Osteoderms of lizards in this clade are unique within Squamata; they typically are circular to polygonal in outline, domed to flat-domed in cross-section, have a vermiculate surface texture, are not compound structures, and do not have imbricate surfaces as on many scincomorph and anguid lizards. We review and characterize the osteoderms of all members of Monstersauria. Osteoderms from the cranium, body, and limbs of Heloderma characteristically have a ring-extension (bony flange) at least partly surrounding the dome. Its presence appears to be a key character distinct to all species of Heloderma, consequently, we propose the presence of a ring-extension to be an apomorphy. Three osteoderms from the Gray Fossil Site range from 1.5 to 3.0 mm in diameter, have the circular shape of helodermatid osteoderms with a domed apical surface, and have the ring-extensions, permiting generic identification. Macrobotanical remains from the Gray Fossil Site indicate an oak-hickory subtropical forest dominated by Quercus (oak) and Carya (hickory) with some conifer species, an understorey including the climbing vines Sinomenium, Sargentodoxa, and Vitis. Plant and mammal remains indicate a strong Asian influence.

Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2016-12-05T15:01:54Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_FilogeografiaLagartoKentropyx.pdf: 2293983 bytes, checksum: 1b13c94dea508023f42f22d8c442e18d (MD5) / Rejected by Edisangela Bastos (edisangela@ufpa.br), reason: Corrigir na citação após o (mestrado) inserir - e não ponto. Incluir ponto no final da citação. Falta sigla do Museu. Corrigir Amazônia no título e citação. Espaço depois do Goeld e antes da vírgula na citação. on 2016-12-05T15:43:51Z (GMT) / Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2016-12-13T13:08:12Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_FilogeografiaLagartoKentropyx.pdf: 2291590 bytes, checksum: 06050e16e66894e28640a20cfc9bfb33 (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2016-12-21T15:46:26Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_FilogeografiaLagartoKentropyx.pdf: 2291590 bytes, checksum: 06050e16e66894e28640a20cfc9bfb33 (MD5) / Made available in DSpace on 2016-12-21T15:46:26Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_FilogeografiaLagartoKentropyx.pdf: 2291590 bytes, checksum: 06050e16e66894e28640a20cfc9bfb33 (MD5) Previous issue date: 2015-03-02 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Kentropyx calcarata é um lagarto heliófilo, florestal e que habita preferencialmente regiões próximas a igarapés, clareiras naturais ou em bordas de florestas. Possui ampla distribuição na Amazônia central e oriental, abrangendo os países Guyana, Guiana Francesa, Suriname e Brasil, onde além da Amazônia ocorre no nordeste e oeste do Cerrado e em parte da Floresta Atlântica. Estudos anteriores envolvendo K. calcarata apontam uma estruturação geográfica para a espécie, a qual ainda necessita ser melhor investigada. Neste estudo, foi analisado como as populações dessa espécie se estruturam ao longo de sua distribuição na Amazônia e quais os possíveis eventos envolvidos no processo de diversificação. Foram utilizados dois marcadores mitocondriais (16S e Cytb) e dois nucleares (DNAH3 e SINCAIP) para testar as hipóteses dos rios como barreiras e dos refúgios florestais. Além disso, foi verificada a possibilidade de haver deslocamento de caracter em populações simpátricas a K. altamazonica. As linhagens inferidas a partir das análises filogenéticas mostram-se estruturadas, do ponto de vista genético e limitadas pelos principais rios da Amazônia oriental. Algumas populações apresentaram um cenário demográfico que condiz com uma expansão populacional recente, que pode estar relacionado com o período de expansão da área florestal.

Two taxa of amphibians, five taxa of reptiles, and eighteen taxa of mammals were collected by screen-washing sediments from the upper Bidahochi Formation at White Cone peak, northeastern Arizona. Five new species of mammals were recovered. They include Perognathoides bidahochiensis (Heteromyidae), Bensonomys yazhi (Cricetidae), Bensonomys bradyi (Cricetidae), Paronychomys alticuspis (Cricetidae), and Martes (Plionictis) repenningi (Mustelidae). Bensonomys yazhi and Bensonomys bradyi are close to the stem of Central and South Americal hesperomyine radiation. The radiation began in the southwest United States and Mexico during the Hemphillian. The middle member of the Bidahochi Formation is dated at 6.7 m. y. by a basalt from Roberts Mesa. The paleomagnetic data and the White Cone local fauna support this middle Hemphillian date.