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Molecular systematics of the native Australian waterfowl (Aves: Anseriformes)Sraml, Michaela, n/a January 1994 (has links)
A consensus classification for the waterfowl (order Anseriformes) has never been
reached. There have been many revisions of the relationships within the order
including those of the monotypic Australian genera. The Southern Hemisphere
anseriforms comprise a large number of monotypic, endemic genera which have
traditionally been linked to the established genera and tribes of the Northern
Hemisphere. More recently, however, with the recognition of endemic Australian
radiations of marsupial mammals (Main and Bakker 1981) and passerine birds (Cracraft
1976; Sibley and Ahlquist 1985; Christidis et al. 1988; Christidis and Schodde 1991),
the affinities of the six monotypic Australian genera of anseriforms have been
questioned (Delacour 1954; Frith 1955, 1964a, b, 1982; Johnsgard 196la, b, 1966;
Davies and Frith 1964; Fullager 1990). In particular, whether they are more closely
related to one another, or whether some or all of these monotypic genera have closer
affinities with the Northern Hemisphere genera. Classification of the taxonomic
relationships of the aberrant Australian endemic species may also corroborate or refute
the recently advanced hypothesis of a Southern Hemisphere origin for the Anseriformes
(Cracraft 1976, 1980; Livezey 1986; Olson 1988).
A 307bp fragment of the mitochondrial cytochrome b gene of the 19 native Australian
anseriforms and four Northern Hemisphere species was enzymatically amplified by
PCR and manually sequenced. The Chicken (Gallus gallus) and Muscovy Duck
(Cairinia moschatd) cytochrome b sequences were obtained from Genbank.
The patterns of evolutionary dynamics within the cytochrome b gene of Anseriformes
appear to conform to those reported in studies of avian and other vertebrate mtDNA. A
new phylogenetic classification for the Anseriformes is proposed. The phylogenetic
trees generated in this study indicate that the monotypic Australian genera, the pygmygeese
and the swans and geese are members of the subfamily Anserinae which appears
to represent a Southern Hemisphere radiation. Within the Anserinae, the Cape Barren
Goose and Freckled Duck link most closely with each other, the Pink-eared Duck
appears to be closely related to the true geese, the Musk Duck is a sister taxon to the
Pink-eared Duck and may be less closely related to the Oxyura than previously thought
and the Magpie Goose is the most divergent member of the Anseriformes included in
this study. The Maned Duck and the remaining native Australian anseriforms are
members of the established European genera and tribes of waterfowl. These species
probably represent a secondary radiation of recent Northern Hemisphere invaders of
Australia. Finally, the data provides some support for the theory of a Southern origin
for the Anseriformes.
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Insights into relationships among rodent lineages based on mitochondrial genome sequence dataFrabotta, Laurence John 12 April 2006 (has links)
This dissertation has two major sections. In Chapter II, complete mitochondrial
(mt DNA) genome sequences were used to construct a hypothesis for affinities of most
major lineages of rodents that arose quickly in the Eocene and were well established by
the end of the Oligocene. Determining the relationships among extant members of such
old lineages can be difficult. Two traditional schemes on subordinal classification of
rodents have persisted for over a century, dividing rodents into either two or three
suborders, with relationships among families or superfamilies remaining problematic.
The mtDNA sequences for four new rodent taxa (Aplodontia, Cratogeomys, Erethizon,
and Hystrix), along with previously published Euarchontoglires taxa, were analyzed
under parsimony, likelihood, and Bayesian criteria. Likelihood and Bayesian analyses
of the protein-coding genes converged on a single topology that weakly supported rodent
monophyly and was significantly better than the parsimony trees. Analysis of the
tRNAs failed to recover a monophyletic Rodentia and did not reach convergence on a
stationary distribution after fifty million generations. Most relationships hypothesized in
the likelihood topology have support from previous data. Mt tRNAs have been largely ignored with respect to molecular evolution or
phylogenetic utility. In Chapter III, the mt tRNAs from 141 mammals were used to
refine secondary structure models and examine their molecular evolution. Both H- and
L-encoded tRNAs are AT-rich with different %G and GC-skew and a difference in skew
between H- and L-strand stems. Proportion of W-C pairs is higher in the H-strand and
GU/UG pairs are higher in the L-strand, suggesting increased mismatch compensation in
L-strand tRNAs. Among rodents, the number of variable stem base-pairs was nearly
75% of that observed across all mammals combined. Compensatory base changes were
present only at divergences of 4% or greater. Neither loop reduction nor an
accumulation of deleterious mutations, both suggestive of mutational meltdown
(Muller's ratchet), was observed. Mutations associated with human pathologies are
correlated only with the coding strand, with H-strand tRNAs being linked to
substantially more of these mutations.
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Molecular systematics of the Eriocaulaceae martinovUnwin, Matthew M. January 2004 (has links)
Thesis (Ph. D.)--Miami University, Dept. of Botany, 2004. / Title from second page of PDF document. Includes bibliographical references (p. 67-83).
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Molecular Systematics of the Eriocaulaceae MartinovUnwin, Matthew M. 22 April 2004 (has links)
No description available.
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Phylogeny and Evolution of Anthopleura (Cnidaria: Anthozoa: Actiniaria)Heestand, Esprit Noel 25 September 2009 (has links)
No description available.
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Filogenia molecular das abelhas Augochlorini (Hymenoptera, Apidae) / Molecular phylogeny of Augochlorini bees (Hymenoptera, Apidae)Gonçalves, Rodrigo Barbosa 23 May 2011 (has links)
Augochlorini (Halictinae) e um elemento comum na região Neotropical, e a historia natural das suas espécies e marcada pela plasticidade quando comparada a outras abelhas. A tribo e grupo-irmão de Halictini, e seus fosseis datam pelos menos do âmbar Dominicano (cerca de 20 milhões de anos). As relações entre os gêneros de Augochlorini foram reconstruídas de maneira insatisfatoria, sendo as hipóteses existentes em parte incongruentes, pouco robustas e baseadas apenas em dados morfológicos. Neste sentido, o presente estudo apresenta uma abordagem filogenética empregando dados moleculares. Para 76 terminais, foram obtidas sequências de DNA de quatro genes, 28S, Fator de Alongamento 1-alfa, Rodopsina Verde e wingless, somando 3043 pares de bases alinhadas. Análises de máxima parcimônia, máxima verossimilhança e inferência bayesiana foram conduzidas para os dados moleculares em conjunto, incluindo ou não regiões de alinhamento ambíguo (alças e íntrons). Os resultados, em consenso, apontam para a parafilia das duas subtribos de Augochlorini sensu Engel, com três grupos de gêneros, gr. Corynura, gr. Rhinocorynura e gr. Chlerogella formando uma politomia na base. Os demais gêneros formam um agrupamento que e dividido em três grandes clados, cujas relações não foram bem resolvidas. O primeiro e composto pelo grupo Megaloptidia e os gêneros Augochloropsis, Augochlorodes e Pseudaugochlora, o segundo pelo grupo Neocorynura mais Chlerogas, Paroxystoglossa e Temnosoma, e o terceiro pelo grupo Augochlora e Caenaugochlora, Megalopta e Thectochlora. As primeiras linhagens de Augochlorini se diversificaram entre 7060 milhões de anos atrás, sendo que desde 50 milhões de anos vem ocorrendo uma gradativa diversificação do grupo. A re-análise da morfologia externa do grupo não foi útil para entender melhor a evolução do grupo que em trabalhos anteriores, inclusive diminuindo o poder explicativo da hipótese gerada pela evidencia total. As hipóteses moleculares apresentaram novas evidencias que guiam futuros estudos para o grupo, para que se possa entender a evolução dentro de cada um dos seus clados. / Augochlorini (Halictinae) is a common element in the Neotropical region, and his natural history is known by their relatively plasticity when compared to other bees. Augochlorini is sister-group of Halictini, and its oldest fossils date from the Dominican amber (about 20 million years before present). The phylogenetic relationships among their genera were only superficially reconstructed, the competing hypothesis are not entirely congruent nor robust and were based only on morphological data. With this background, this study aims to present a molecular phylogeny to Augochlorini. It was obtained, for 76 terminals, DNA sequences of four genes, 28S, Elongation Factor 1-alpha, Green Rodopsin and Wingless, giving a 3043 base pair alignment. Maximum parsimony, maximum likelihood and Bayesian inference analyses were carried out for the molecular data, including or excluding regions of ambiguous alignment (loops and introns). The results, based on consensus trees, suggest the paraphyly of both Augochlorini subtribes (sensu Engel), with three groups of genera, gr. Corynura, gr. Rhinocorynura e gr. Chlerogella forming a basal polytomy with a clade containing the remaining genera. This clade has three subgroups, whose phylogenetic relationships were not well stabilized. The first group consists of gr. Megaloptidia and Augochloropsis, Augochlorodes, and Pseudaugochlora, the second group of gr. Neocorynura plus Chlerogas, Paroxystoglossa, and Temnosoma, and the third group consists of gr. Augochlora and Caenaugochlora, Megalopta, and Thectochlora. The first Augochlorini lineages diversified by 70 to 60 million years ago, and since 50 mya there has been a gradual diversification of the group. The reanalysis of augochlorines external morphology was not helpful for understanding the evolution of the group, and also reduced the explanatory power of the total evidence hypothesis. The molecular hypothesis brought new evidences to guide future studies for the group, and positively favored the conception about the evolution of Augochlorini main clades.
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Revisão sistemática do gênero Bunodosoma Verrill, 1899(Cnidaria: Actiniaria: Actiniidae) e estudo de populações do Atlântico Sul / Systematic review of the genus Bunodosoma Verrill, 1899 (Cnidaria: Actiniaria: Actiniidae) and study of populations from the South Atlantic OceanBeneti, Julia Silva 15 July 2016 (has links)
Bunodosoma é um gênero cosmopolita de anêmonas que apresentam pólipos grandes e conspícuos, sendo comuns em ambientes costeiros. Atualmente compreende 14 espécies válidas e, apesar de estas serem utilizadas em estudos filogenéticos dentro da ordem Actiniaria, não existem abordagens visando resolver os problemas intragenéricos, e o conhecimento da diversidade do gênero é limitado por problemas taxonômicos e de identificação. Dessa forma, é necessário que se estabeleçam os limites entre a variação inter e intraespecífica dos pólipos, e para isso devem-se integrar informações morfológicas e moleculares. As espécies B. cangicum, B. caissarum e B. zamponii, endêmicas do Atlântico Sul e com diversos registros ao longo da costa, são um interessante modelo para o estudo destas variações. Portanto, os objetivos desse projeto são: 1) realizar a revisão sistemática e propor uma hipótese filogenética para o gênero Bunodosoma com base em evidências moleculares; 2) explorar a viabilidade da utilização do marcador molecular ITS nos estudos de populações de anêmonas e testar outros marcadores nucleares que possam representar as diferenças genéticas inter e intraespecíficas; e 3) verificar a variabilidade morfológica (utilizando dados de tamanhos de cnidocistos) e molecular intraespecífica das espécies B. caissarum e B. cangicum. A revisão sistemática, apresentada no Capítulo 1, evidenciou que 14 espécies podem ser reconhecidas, apesar de o status taxonômico de três delas permanecer aberto a testes. A análise filogenética com os dados moleculares disponíveis não fornece evidência para o monofiletismo de Bunodosoma, que foi recuperado parafilético em relação a outras espécies da família Actiniidae. No Capítulo 2, as análises filogenéticas e filogeográficas com o marcador ITS forneceram suporte para o reconhecimento de dois clados: o primeiro composto por indivíduos de B. caissarum e o segundo por indivíduos de B. cangicum e B. zamponii. Apesar de se mostrar útil na delimitação de grandes grupos, o ITS é um marcador eficiente na delimitação de populações. Em relação à variação morfométrica dos cnidocistos, os resultados apresentados no Capítulo 3 demonstram que, caso bem empregados e analisados, alguns tipos de nematocistos podem ter valor taxonômico na delimitação de populações de anêmonas. O conjunto dos resultados do presente estudo contribuem para um melhor conhecimento da sistemática e biologia desses organismos, além de gerar subsídios para a compreensão de aspectos evolutivos da ordem Actiniaria / Bunodosoma is a cosmopolite genus of sea anemones of large and conspicuous polyps, common in costal environments. It currently comprises 14 species and, despite being employed in phylogenetic studies within the order Actiniaria, no study so far has tried to solve intrageneric problems in Bunodosoma, so the knowledge about the genus\' diversity is limited by problems of taxonomy and identification. Thus, it is necessary to establish the limits of inter and intraspecific variation of the polyps. To accomplish that, integrative studies using morphological and molecular data must be carried out. The species B. cangicum, B. caissarum, and B. zamponii are endemic of the South Atlantic Ocean. They represent an interesting model to study the aforementioned variation. Therefore, the goals of this study are: 1) to review the systematics and to propose a phylogenetic hypothesis for the genus Bunodosoma based on molecular evidence; 2) to explore the usage of the molecular marker ITS in population studies of sea anemones, as well as to test other nuclear regions that may show inter and intraspecific variation; and 3) to access the phenotypic (based on cnidocyst size variation) and molecular intraspecific variability of B. caissarum and B. cangicum. The systematic review, presented in Chapter 1, showed that there are 14 recognized species; three of them need further analyses. The molecular phylogenetic analysis did not provide evidences for the monophyly of Bunodosoma, which was recovered paraphyletic regarding other species of the family Actiniidae. In Chapter 2, the phylogenetic and phylogeographic analysis of ITS provided support to recognize two major clades: one composed by B. caissarum individuals and the other by individuals of B. cangicum plus B. zamponii. Despite been useful to delimit major groups, the ITS marker is not efficient to delimit populations. Regarding the morphometric variation of the cnidocysts, the results presented in Chapter 3 demonstrated that, when employed with caution, some types may present taxonomic value in population delimitation. The results of the present study contribute to a better understanding of the systematics and the biology of Bunodosoma, and provide support to the comprehension of evolutionary aspects of the order Actiniaria
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Filogenia, biogeografia e revisão taxonômica de Nycticalanthus Ducke e Spiranthera A.St.-Hil. (Rutaceae, Galipeeae) / Phylogeny, biogeography and taxonomic revision of Nycticalanthus Ducke and Spiranthera A.St.-Hil. (Rutaceae, Galipeeae)Brito, Lilian de Andrade 05 December 2017 (has links)
Os gêneros Nycticalanthus (monotípico) e Spiranthera (quatro espécies), pertencentes à família Rutaceae, tribo Galipeeae, são semelhantes morfologicamente e possuem distribuição restrita à América do Sul. São predominantemente arvoretas ciófilas de florestas úmidas, exceto Spiranthera odoratissima, que possui hábito arbustivo savânico e é a espécie de distribuição mais ampla, com a maior variabilidade morfológica. Este estudo teve como objetivo investigar as relações de parentesco entre Nycticalanthus e Spiranthera e suas espécies, utilizando dados moleculares (região ETS do DNA nuclear e espaçador trnL-F do DNA plastidial), visando entender os processos subjacentes à sua diversificação e biogeografia, além de realizar uma revisão taxonômica do grupo. Baseado na filogenia obtida e nas características morfológicas compartilhadas entre as espécies de ambos os gêneros, muitas delas sinapomórficas, é proposta a sinonimização do gênero monotípico Nycticalanthus sob Spiranthera. A revisão taxonômica apresentada baseia-se em uma extensa análise morfológica do grupo, incluindo expedições a campo e estudo de espécimes de herbários, elaboração de chave de identificação, descrição e ilustrações das seis espécies reconhecidas, incluindo uma espécie nova de Iquitos, Peru, além de dados de distribuição geográfica, habitats e variabilidade morfológica de cada táxon / The genera Nycticalanthus Ducke (monotypic) and Spiranthera A.St.-Hil. (four species), belonging to Rutaceae, tribe Galipeeae, are morphologically similar and restricted to South America. They are mostly sciophyllous treelets from rainforests, except for Spiranthera odoratissima, the most widespread species, which is a shrub inhabiting savannic formations and showing the highest morphological variation. This study investigated the phylogenetic relationships between the two genera, and among their species as well, using molecular data (ETS from the nuclear DNA, and trnL-F spacer from the plastidial DNA), aiming at understanding the processes involved in their diversification and biogeographic history. I also studied the taxonomic circunscription of both genera (all species included) carrying out a taxonomic revision of them. Based on the phylogeny and morphological characteristics shared by the species of both genera (most of them synapomorphies), I have proposed the synonymization of the monotypic genus Nycticalanthus under Spiranthera. The taxonomic revision is based on extensive morphological analysis of the group, including collecting and observation during field trips, and study of herbarium specimens. I also present identification keys, descriptions and illustrations for all the six species, including a new one from Iquitos, Peru, as well as updated geographic distribution range, habitats, and discussion about the morphological variation of each taxon
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Molecular systematics of the South African gobiid fishes of the genus glossogobius gill, 1862 (teleostei : gobiidae)Maake, Pholoshi Abram January 2009 (has links)
Thesis (M.Sc. (Zoology)) --University of Limpopo, 2009 / The genus, Glossogobius Gill, 1862 belongs to the family Gobiidae, a large fish family represented by several thousand species. In southern African there are about 51 genera comprising about 107 species. It has been suggested that gobies underwent an extensive ecological radiation, with species
diversifying into marine, brackish and freshwater habitats. The genus Glossogobius has about 22 species with an Indo-west Pacific distribution. The overall aim of the current study was to examine the systematics of Glossogobius in southern Africa using molecular markers in an attempt to clarify
the geographic distribution and species status.
A total of 131 individuals of G. callidus were collected from rivers and estuaries throughout the species’ distribution in two southern African biogeographic regions (subtropical and warmtemperate) using six-meter seine nets, while individuals of G. tenuiformis were only collected in
KwaZulu-Natal region. Additional specimens and taxa were downloaded from Genbank and also loaned from the SAIAB DNA collection and the Art Gallery and Museum of the Northern Territory(NTM), Darwin Australia. This study employed mtDNA cytochrome b (cyt b) and the nuclear S7 ribosomal protein gene intron 1 (S7 intron 1) as genetic markers. In determining the phylogeographic
structure of the river goby general methods such as AMOVA, demography analyses, network of haplotypes and phylogenetic tree reconstruction were employed. Evolutionary relationships within the genus were resolved by employing parsimony (MP), Bayesian Inference (BI) and Maximum likelihood (ML) tree reconstruction analyses. Both MP and ML were computed in PAUP* while BI was computed using Mr Bayes.Initially, a large-scale assessment of the genetic structure and diversity of G. callidus was undertaken. This species has a wide distribution in most estuaries and coastal river systems along the
east coast of southern Africa, and in inland freshwater systems from the north-eastern parts. Overall,patterns of haplotype relatedness, high haplotypic diversity related to low nucleotide diversity, and
mismatch distribution analysis supported a population expansion hypothesis with continued restricted dispersal and gene flow. Two major historically isolated lineages (5% divergence, cyt b)were identified within this species, one comprising subtropical samples (KwaZulu-Natal lineage),and the other including the majority of the warm temperate localities and a few subtropical localities(EC, Eastern Cape lineage). Glossogobius callidus individuals collected from riverine localities within the EC lineage were geographically structured and support the general hypothesis of structure among freshwater species while the estuarine individuals were less structured. Although, the individuals from these two lineages were morphologically inseparable, the high genetic separation between the two conforms to the reports that G. callidus is a species complex. The results further revealed some evolutionary significant units (Nkanini/Kosi bay lineage, and Mozambique) in the KZN lineage, KwaZulu-Natal. However, there were other identified localities with restricted gene flow and some degree of reproductive isolation that were not evolutionary significant. Thus, the results indicate that G. callidus is a species with relatively strong population and phylogeographic
structure in southern Africa.The validity of the species of the genus Glossogobius in southern Africa (G. callidus and G. giurus
with its synonymy G. tenuiformis) was investigated by estimating the relationships among the Glossogobius taxa in southern Africa, using the same molecular markers. Based on a model selected under AIC in Modeltest, ML analysis of the dataset also recovered a phylogram which was similar to
MP and BI in recognising the major clades in many respects. All analyses recovered monophyly for all southern African species of the genus. Although the cyt b analyses included Glossogobius species from Australia, there was no evidence of a phylogeographic break between the two continents.
However, it appears that each southern African Glossogobius species has a sister species occurring in Australia according to the cyt b dataset. Glossogobius aureus was revealed as the probable sister species to G. tenuiformis while the African G. giuris group was monophyletic with the Australian G.
giuris. The two G. callidus groups that appear to represent two unique species (sp. 1 and sp. 2) were also sister taxa to the undescribed Glossogobius sp. from Australia. It could be postulated that this
inter-continental species relationships were a result of either allopatric or sympatric speciation events, to the ancestral taxa of each of these three sister groups which in turn split up during the Gondwana breakup. The inclusion of G. celebius (a freshwater and brackish species with an Asian
and Oceania distribution) in the S7 intron dataset did not affect the monophyly of southern African species. However, this species appears to be more basal in the genus than the southern African
species. The results further indicated that G. tenuiformis (previously a synonym of G. giuris) forms a separate clade that is distinct from the G. giuris species group. Although G. tenuiformis and G. giuris
formed a monophyletic group in all analyses involving the S7 intron 1, individuals from each species were monophyletic and strongly supported. The scanning electron micrographs of the cheek papillae of the two species further revealed morphological differences. The congruence between both morphology and molecular data indicated that G. tenuiformis is unequivocally distinct from G. giuris and it is therefore suggested that the taxonomic status of the G. giuris group be revised. / National Research Foundation, the Ernst and Ethel Eriksen Trust, the South African Institute for Aquitic Biodiversity (SAIAB), and the University of Limpopo
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Molecular Systematics, Historical Biogeography, and Evolution of Spider Wasps (Hymenoptera: Pompilidae)Rodriguez, Juanita 01 May 2014 (has links)
Spider wasps are solitary parasitoids that use one spider to lay a single egg. Even though their behavior seems homogeneous, the features pertaining to nesting and hunting behavior are diverse for different species. There are approximately 5,000 described species, in 120 genera, but there are probably many undescribed species. The systematics of Pompilidae has been studied in recent years, but only morphological data have been used for this purpose. Because of the morphological homogeneity of spider wasps, molecular data may prove promising for understanding the systematics of the group. Furthermore, dated molecular phylogenies calibrated with fossil data may allow studying the historical biogeography and evolution of the group. I used the nuclear molecular markers elongation factor–1 α F2 copy (EF1), long–wavelength rhodopsin (LWRh), wingless (Wg), RNA polymerase II (Pol2), the D2–D3 regions of the 28S ribosomal RNA (28S), and the mitochondrial Cytochrome C Oxidase I (COI) in a Bayesian and Maximum Likelihood framework, to reconstruct the phylogenies of four main Pompilidae groups: the subfamily Pompilinae, the tribe Aporini, the genus Psorthaspis, and the genus Drepanaporus. I also studied the fossil Pompilidae, and used those results to produce time-calibrated phylogenies of Pompilinae, Aporini, and Psorthaspis. Molecular phylogenetic results support the utility of the use of molecular markers for species delimitation and sex-associations in Pompilidae. In addition, the use of dated phylogenies supports the correlation of host use with diversification rate-shifts, the coevolution of mimicry between pompilids and velvet ants, and various biogeographical hypotheses never tested before for spider wasps.
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