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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Αντιστροφή περιέλιξης στο χερσαίο σαλιγκάρι Albinaria : τι λένε τα μοριακά δεδομένα;

Σταματάκη, Ειρήνη 07 June 2013 (has links)
Η περιέλιξη του σώματος είναι ένα φαινόμενο που συναντάται αποκλειστικά στα Γαστερόποδα και παρουσιάζει ιδιαίτερο ενδιαφέρον για τη γενετική, την εξελικτική και την αναπτυξιακή βιολογία. Η κατεύθυνση της περιέλιξης (δεξιόστροφη ή αριστερόστροφη) καθορίζεται από ένα άγνωστο γονίδιο, το οποίο παρουσιάζει μητρικό επηρεασμό. Στα περισσότερα είδη, τα άτομα αντίστροφης περιέλιξης δεν μπορούν να ζευγαρώσουν, συνεπώς η αλλαγή στην κατεύθυνση της περιέλιξης προκαλεί αναπαραγωγική απομόνωση. Η συντριπτική πλειονότητα των ειδών στο γένος Albinaria έχει αριστερόστροφη περιέλιξη. Οι μόνες δεξιόστροφες μορφές εμφανίζονται αποκλειστικά στη νότια Πελοπόννησο. Όλες οι δεξιόστροφες μορφές θεωρείται, με βάση τα μορφολογικά δεδομένα, ότι ανήκουν σε ένα είδος, το Albinaria voithii. Ωστόσο, επειδή η μορφολογική και η γενετική διαφοροποίηση στα χερσαία μαλάκια και ειδικότερα στο γένος Albinaria συχνά δείχνει αντικρουόμενα αποτελέσματα και καθώς δεν υπάρχουν στοιχεία σχετικά με τη φυλογένεση του συγκεκριμένου ζώου, δεν έχει αποσαφηνιστεί εάν όλοι οι δεξιόστροφοι πληθυσμοί συγκροτούν μία μονοφυλετική ομάδα και αν η αντιστροφή της περιέλιξης συνέβη μία ή περισσότερες φορές. Επιπλέον, πολλές φορές τα δεξιόστροφα άτομα ζουν συμπάτρια με αριστερόστροφα, αλλά σπανίως διασταυρώνονται με αυτά. Προκύπτει έτσι το ερώτημα εάν η αντιστροφή της περιέλιξης εμφανίστηκε ως ένα μέσο μείωσης της γονιδιακής ροής για να αποφευχθεί η δημιουργία υβριδίων με χαμηλή αρμοστικότητα. Σε αυτήν την εργασία ελέγξαμε εάν οι δεξιόστροφοι πληθυσμοί της Albinaria συγκροτούν μια μονοφυλετική ομάδα και εάν αντιστοίχως το φαινόμενο της αντιστροφής της περιέλιξης έχει συμβεί μία ή περισσότερες ανεξάρτητες φορές. Για το σκοπό αυτό χρησιμοποιήσαμε αριστερόστροφα και δεξιόστροφα άτομα που συλλέχθηκαν από 25 τοποθεσίες της Πελοποννήσου. Στις 10 περιοχές υπήρχαν μόνο αριστερόστροφοι αντιπρόσωποι, στις 8 μόνο δεξιόστροφοι, ενώ στις υπόλοιπες 7 περιοχές υπήρχε συμπάτρια παρουσία αριστερόστροφων και δεξιόστροφων πληθυσμών. Η εκτίμηση της γενετικής ποικιλότητας και ο προσδιορισμός των φυλογενετικών σχέσεων αυτών των πληθυσμών έγινε χρησιμοποιώντας έναν πυρηνικό (ITS1) και δύο μιτοχονδριακούς μοριακούς δείκτες (COΙ και 16S). Οι φυλογενετικές αναλύσεις του πυρηνικού και των μιτοχονδριακών δεικτών οδήγησαν στην παραγωγή δέντρων ανόμοιας τοπολογίας. Τα δέντρα των μιτοχονδριακών δεικτών έχουν τρεις δεξιόστροφους και τρεις αριστερόστροφους κλάδους, ενώ στα δέντρα του πυρηνικού υπάρχουν δύο αριστερόστροφοι κλάδοι, ένας δεξιόστροφος και ένας με αριστερόστροφα και δεξιόστροφα άτομα. Από τις φυλογενετικές αναλύσεις του πυρηνικού δείκτη συμπεραίνουμε ότι τα δεξιόστροφα άτομα δεν συγκροτούν μία μονοφυλετική ομάδα και ότι η δεξιοστροφία στο γένος Albinaria έχει εμφανιστεί ανεξάρτητα τουλάχιστον δύο φορές, καθώς τα δεξιόστροφα άτομα τοποθετούνται σε δύο διαφορετικούς κλάδους, αλλά το δεξιόστροφο αλληλόμορφο εμφανίστηκε μόνο μία φορά. Επίσης, η εμφάνιση της δεξιοστροφίας πρέπει να είναι ένα παλιό εξελικτικό γεγονός που συνέβη πριν από αρκετά εκατομμύρια χρόνια, καθώς τα συμπάτρια αριστερόστροφα και δεξιόστροφα άτομα δεν έχουν πρόσφατο κοινό πρόγονο. Ακόμα, μπορούμε να συμπεράνουμε ότι δεν υπάρχει γονιδιακή ροή ανάμεσα στα συμπάτρια δεξιόστροφα και αριστερόστροφα άτομα, επειδή αυτά τοποθετούνται σε διαφορετικούς κλάδους. Μία πιθανή ερμηνεία της τοπολογίας του δέντρου των μιτοχονδριακών δεικτών είναι ότι ο μητρικός κυτταροπλασματικός παράγοντας που καθορίζει την κατεύθυνση της περιέλιξης στο έμβρυο, πιθανώς συμπαρασύρει τη μεταβίβαση ενός τύπου μιτοχονδρίου. / Body coiling is a phenomenon occurring exclusively in gastropods and it has important implications for their genetics, evolution and development. The direction of coiling (dextral or sinistral) is determined by an unknown gene that has maternal effect. In most species, individuals with reverse coiling cannot mate, thus the inversion of coiling might cause reproductive isolation. The vast majority of species and populations in the pulmonate genus Albinaria coil sinistrally. The only dextral morphs can be found restricted in southern Peloponissos and according to their morphology they belong to a single species, Albinaria voithii. However, morphological and genetic differentiation in mollusks, (especially in genus Albinaria), often show conflicting results and since phylogenetic studies are lacking, it is not clear whether all dextral populations form a monophyletic group and if the inversion of coiling has occurred more than once. Moreover, dextral populations are often found in sympatry with sinistral ones, but rarely mate with them. Therefore, it is interesting to examine if the inversion of coiling emerged as a means to reduce gene flow and the production of unfitted hybrids. In this study we tested whether dextral populations form a monophyletic group and if the inversion of coiling occurred independently more than once. For this purpose we used dextral and sinistral individuals collected from 25 localities in Peloponissos. In 10 localities there were only sinistral populations, in 8 only dextral ones, while in the remaining 7 localities sympatric sinistral and dextral populations were found. The assessment of genetic diversity and the determination of phylogenetic relationships of these populations were performed using a nuclear (ITS1) and two mitochondrial markers (COI and 16S). Phylogenetic analyses of nuclear and mitochondrial markers produced trees with different topologies. Trees of mitochondrial markers have three dextral and three sinistral clades, whereas the trees of nuclear marker have two sinistral clades, one dextral and one clade with both sinistral and dextral individuals. From the phylogenetic analyses of the nuclear marker we can conclude that dextral individuals do not form a monophyletic group and that dextrality has evolved independently at least twice within the genus Albinaria, as dextral individuals are placed in two different clades. However, it seems that the dextral allele appeared only once. Also, the evolution of dextrality must be an old evolutionary event that occurred before several million years, because sympatric sinistral and dextral individuals do not share a recent common ancestor. Moreover, we can conclude that there is no gene flow between sympatric dextral and sinistral individuals because they are placed in different clades. A possible scenario that explains the topology of the tree of mitochondrial markers is that the maternal cytoplasmic factor that determines the direction of coiling in the embryo probably causes the inheritance of mitochondria of a certain type.
42

Polyphasic approach to the taxonomy of selected cyanobacteria / Polyphasic approach to the taxonomy of selected cyanobacteria

MAREŠ, Jan January 2015 (has links)
The modern taxonomic revision of cyanobacteria is a work in progress, with both theoretical and practical challenges to be addressed. This thesis investigated selected terrestrial cyanobacterial taxa using a polyphasic approach, based on molecular phylogenetic analysis and accompanied by phenotypic characterization and nomenclatural treatment. Diverse methodological approaches were used including optical and transmission electron microscopy, molecular analysis (DNA sequencing) of cyanobacterial strains, single cells and filaments, and phylogenetic analysis of multiple genomic loci. This study provided systematic revisions of individual cyanobacterial genera and the entire phylum, and suggestions for future study projects.
43

Revisão taxonômica das planárias terrestres de Geoplana (Platyhelminthes, Tricladida) / Taxonomic revision of the land planarians of the genus Geoplana (Platyhelminthes, Tricladida)

Ana Laura Almeida dos Santos 30 September 2016 (has links)
As planárias terrestres (Platyhelminthes, Geoplanidae) são vermes de vida livre, hermafroditas e predadores que habitam principalmente florestas úmidas. A subfamília Geoplaninae, restrita à região neotropical, compreende cerca de 270 espécies. Geoplana Stimpson, 1857, seu gênero-tipo, é atualmente composto por três espécies (Geoplana vaginuloides (Darwin, 1844), Geoplana chita Froehlich, 1956 e Geoplana pulchella Schultze & Müller, 1857), todas da mata Atlântica brasileira. A espécie-tipo do gênero, G. vaginuloides, foi descrita por Darwin a partir de um único espécime que coletou no Rio de Janeiro (RJ) em 1832. Darwin baseou-se apenas em caracteres de morfologia externa e o paradeiro do material tipo é desconhecido. Posteriormente, outros autores estudaram a espécie e atribuíram-na sete padrões de coloração dorsal, mas um estudo filogenético recente com dois indivíduos de coloridos dorsais distintos indicou que a espécie é polifilética, justificando a necessidade de sua circunscrição para estabilizar a taxonomia da subfamília. Este trabalho tem por objetivo fazer uma revisão taxonômica do gênero utilizando dados fenotípicos e genotípicos. Todo o material disponível das espécies de Geoplana citado na literatura foi analisado, além de outros espécimes disponíveis em coleção ou coletados para este propósito. As principais características morfológicas que permitiram distinguir as espécies são: cor do dorso, forma e desenvolvimento do bulbo peniano, região de encontro dos ductos eferentes, região do átrio masculino em que se assenta a papila peniana, comprimento relativo da papila peniana e distribuição das secreções associadas, espessura da musculatura do ducto ejaculatório, e tipo de epitélio de revestimento do átrio feminino. As análises filogenéticas moleculares foram realizadas a partir de sequências do gene mitocondrial Citocromo Oxidase I (COI) e do gene nuclear Fator de Elongação 1-alfa (EF-1-), isolados e concatenados, usando parcimônia e máxima verossimilhaça como critérios de optimalidade. Os resultados moleculares e morfológicos são congruentes e revelaram que G. pulchella é monofilética, mas G. chita e G. vaginuloides são polifiléticas. As relações entre as espécies variam em função do gene e do critério de optimalidade utilizados. 13 clados são constantes, cada um composto por indivíduos homogêneos morfologicamente. Esta congruência permite reconhecer 13 espécies, dez delas com aspecto compatível com G. vaginuloides, incluindo membros propostos por outros autores como coespecíficos: Geoplana vaginuloides (Darwin, 1844), G. apua Almeida & Carbayo, nom. nov., G. mogi Almeida & Carbayo, nom. nov., G. piratininga Almeida & Carbayo, nom. nov., G. paranapiacaba Almeida & Carbayo, sp. n., G. caraguatatuba Almeida & Carbayo sp. nov., G. ibiuna Almeida & Carbayo sp. nov., G. cananeia Almeida & Carbayo, sp. n., G. cambara Almeida & Carbayo sp. nov., G. iporanga Almeida & Carbayo sp. nov., G. pulchella Schultze & Müller, 1857, G. chita Froehlich, 1956, e G. boraceia Almeida & Carbayo, nom. nov. Estas espécies apresentam musculatura parenquimática longitudinal, característica incomum em Geoplaninae (conhecida apenas em Imbira) e ausente por definição em Geoplaninae. Propomos, então, emenda a diagnose de Geoplana e da subfamília. / Land planarians (Platyhelminthes, Geoplanidae) are hermaphroditic, free-living and predatory organisms, that inhabit humid forests. The subfamily Geoplaninae is restricted to the Neotropical region, and includes ca. 270 species. Currently, Geoplana Stimpson, 1857, the type-genus of the subfamily, comprises three species, Geoplana vaginuloides (Darwin, 1844), Geoplana chita Frohelich, 1956 e Geoplana pulchella Schultze & Müller, 1857, all of them found in the Brazilian Atlantic forest. The original description of the type-species of the genus, G. vaginuloides, was described from a single individual collected by Darwin in Rio de Janeiro (Brazil) in 1832. He described only the external aspect of the specimen and its location remains unknown. Subsequently, other authors studied this species and provided up to seven chromatic patterns of the dorsum, but in a recent paper, a polyphyletic condition of the species was demonstrated by means of molecular data. This situation entails the need to circumscribe the species in order to stabilize the txonomy of the subfamily. This works aims at achieving a taxonomic revision of the genus by using phenotypic and molecular data. All available material of Geoplana mentioned in literatute was studied, besides additional specimens from other collections or here collected for this purpose. Phenotypic examination enabled us to recognize up to 13 morphospecies, which differ each other mainly by means of these features: color of the dorsum, shape and relative development of the penis bulb; position of the junction of the sperm ducts with each other; region of the male atrium from which the penis papilla projects; relative length of the penis papilla; distribution of the secretions within the papilla; relative thickness of the musculatura wrapping the ejaculatory duct; and type of epithelium lining the female atrium. Molecular phylogenetic analyses were performed with sequences of the mitochondrial region of the cytochrome oxidase I gene and the nuclear region of the elongation factor 1-alpha, both separately and concatenated. Parsimony and maximum likelihood were used as optimality criteria. Morphological and molecular data are congruent with each other and revealed a monophyletic condition of G. pulchella, but a polyphyletic condition of G. chita and G. vaginuloides. Interrelationships among internal branches varied depending on the gene and the optimality criterion and have relatively low support. However, the external branches are constituted by morphologically homogeneous individuals. This congruence enabled us to recognize 13 species; the external aspect of ten species compares well with G. vaginuloides, including members considered conspecific in the literature. These results lead us to recognize the following taxonomic entities: Geoplana vaginuloides (Darwin, 1844), G. apua Almeida & Carbayo, nom. nov., G. mogi Almeida & Carbayo, nom. nov., G. piratininga Almeida & Carbayo, nom. nov., G. paranapiacaba Almeida & Carbayo, sp. n., G. caraguatatuba Almeida & Carbayo sp. nov., G. ibiuna Almeida & Carbayo sp. nov., G. cananeia Almeida & Carbayo, sp. n., G. cambara Almeida & Carbayo sp. nov., G. iporanga Almeida & Carbayo sp. nov., G. pulchella Schultze & Müller, 1857, G. chita Froehlich, 1956, and G. boraceia Almeida & Carbayo, nom. nov. All these species possess longitudinal parenchymatic musculature, an uncommon characteristic in Geoplaninae (only unknown from Imbira), which is, by definition, absent in the subfamily. Accordingly, we suggest to emend the diagnoses of the Geoplana and Geoplaninae.
44

Filogenia molecular dos anostomidae e filogeografia das espécies com cromossomos sexuais ZZ/ZW do gênero Leporinus

Malaver, Jorge Luis Ramirez 30 April 2015 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-02-01T10:30:20Z No. of bitstreams: 1 TeseJLRM.pdf: 6417864 bytes, checksum: 533196c58789b808d650a9caa133729c (MD5) / Approved for entry into archive by Camila Passos (camilapassos@ufscar.br) on 2017-02-01T10:36:43Z (GMT) No. of bitstreams: 1 TeseJLRM.pdf: 6417864 bytes, checksum: 533196c58789b808d650a9caa133729c (MD5) / Approved for entry into archive by Camila Passos (camilapassos@ufscar.br) on 2017-02-01T10:39:18Z (GMT) No. of bitstreams: 1 TeseJLRM.pdf: 6417864 bytes, checksum: 533196c58789b808d650a9caa133729c (MD5) / Made available in DSpace on 2017-02-01T10:40:20Z (GMT). No. of bitstreams: 1 TeseJLRM.pdf: 6417864 bytes, checksum: 533196c58789b808d650a9caa133729c (MD5) Previous issue date: 2015-04-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The family Anostomidae has approximately 150 species, belonging to 14 genera. Several attempts to define the subfamilies were unsuccessful. Within the family, the Leporinus genus is the most specious (approx. 90 valid species). A ZZ/ZW sex chromosomes system has been described for seven species of Leporinus, which would constitute a monophyletic group. Another ZW sex chromosomes system has been described only for Leporinus geminis. The ZW Leporinus species presents an interesting distribution, being distributed in almost every major South American basins. The aim of this study was to reconstruct the phylogenetic relationships of family Anostomidae and several species of Leporinus genus. Also, evaluate the monophyly of species with ZZ/ZW sex chromosomes, as well as de novo origin of the sex chromosomes described for Leporinus geminis. Additionally, It will be evaluated the functionality of the DNA barcodes for the family Anostomidae. Another aim was to evaluate the phylogeographic distribution pattern of ZZ/ZW Leporinus species. For the barcode was analyzed the Cytochrome Oxidase subunit I of 430 individuals (122 lineages). Distance analyzes were performed using the K2P model. For the molecular phylogeny were amplified two mitochondrial genes (Cytochrome B and Cytochrome Oxidase I) and three nuclear markers (recombination activating gene 1 and 2, and Myosin, heavy chain 6, cardiac muscle, alpha gene) from 104 lineages (69 nominal species). Phylogenetic trees were constructed using methods of maximum parsimony, maximum likelihood and Bayesian species tree. For the phylogeographic analysis, was constructed a calibrated tree, including the 15 recovered linages for the ZW group. The dataset was calibrated using the rise of the Eastern Cordillera, about 12 million years ago. The DNA barcode is a powerful tool for the linage identification of the family Anostomidae. The average intraspecific distance was 0.106%. The lowest interspecific distance was 0.479%. The genetic distances founded show that the threshold to separate lineages is lower than traditionally suggested for fishes (1% and 2%). The family Anostomidae is monophyletic, being found twenty-two clades within it. The subfamilies Anostominae sensu Winterbottom (1980) and Leporellinae were recovered as valid, while a more inclusive Leporininae has to be redescribed. The Leporinus genus was recovered as paraphyletic, requiring several taxonomic changes. The ZZ/ZW Leporinus species were recovered as a monophyletic group. Sex chromosomes of Leporinus geminis were confirmed as an evolutionary convergence. The evolutionary history of ZZ/ZW Leporinus species proved to be complex. The lineage speciation of the proto-Amazon-Orinoco was given by paleogeographic processes, while the lineage diversification in the Eastern Brazilian Shield was predominantly hydrogeological and by dispersion through paleo-basins in low sea level period. / A família Anostomidae possui aproximadamente 150 espécies, distribuídas em 14 gêneros. Diversas tentativas de delimitar as subfamílias não têm tido muito sucesso. Na família o gênero Leporinus é o mais especioso (aprox. 90 espécies válidas). Um sistema de cromossomos sexuais ZZ/ZW foi descrito para sete espécies de Leporinus, que formariam um grupo monofilético. Outro sistema de cromossomos sexuais ZW foi descrito unicamente para Leporinus geminis. As espécies de Leporinus com cromossomos ZW apresentam uma interessante distribuição, estando distribuídas praticamente em todas as grandes bacias hidrográficas sul-americanas. O intuito do estudo é reconstruir as relações filogenéticas da família Anostomidae e das distintas espécies do gênero Leporinus. Avaliar a monofilia do grupo de espécies com cromossomos sexuais ZZ/ZW, assim como a origem de novo dos cromossomos sexuais descritos para Leporinus geminis. Será avaliada também a funcionalidade dos códigos de barras de DNA para as espécies da família Anostomidae. Outro objetivo será avaliar o padrão de distribuição filogeográfica das espécies do gênero Leporinus que possuem sistemas de cromossomos sexuais ZZ/ZW. Para o barcode foi analisado o Citocromo oxidase I de 430 indivíduos (122 linhagens). Foram realizadas análises de distância, usando o modelo K2p. Para a filogenia molecular foram amplificados dois genes mitocondriais (Citocromo B e Citocromo oxidase I) e três nucleares (o gene de ativação da recombinação 1 e 2 e a cadeia pesada 6 da miosina, isoforma alfa do músculo cardíaco) para 104 linhagens (69 espécies nominais). Foram construídas árvores filogenéticas usando os métodos de máxima parcimônia, máxima verossimilhança e bayesian species tree. Para a análise filogeográfica, construiu-se uma árvore calibrada, incluídos as 15 linhagens recuperadas para o grupo ZW. O evento de calibração foi o surgimento da Cordilheira Oriental há 12 Milhões de anos. O DNA barcode é uma ferramenta eficiente para a identificação das linhagens da família Anostomidae. A média da distância intraespecífica foi de 0,106%. O menor valor de distância interespecífica foi de 0,479%. As distâncias genéticas encontradas mostram que o limiar para separar linhagens é mais baixo que os sugeridos para peixes (1% ou 2%). A família Anostomidae é monofilética, sendo encontrados vinte e dois clados dentro dela. As subfamílias Anostominae sensu Winterbottom (1980) e Leporellinae foram recuperadas como válidas, enquanto que um mais abrangente Leporininae precisa ser redescrito. O gênero Leporinus foi recuperado como parafilético, sendo necessárias várias mudanças taxonômicas. As espécies de Leporinus com cromossomos sexuais ZZ/ZW foram recuperadas dentro de um grupo monofilético. Os cromossomos sexuais de Leporinus geminis foram confirmados como uma convergência evolutiva. A história evolutiva das espécies de Leporinus com cromossomos sexuais ZZ/ZW mostrou-se complexa. Sendo que a especiação na linhagem do proto-Amazonas-Orinoco foi dada por processos paleogeográficos, enquanto que o processo de diversificação na linhagem do leste do Escudo Brasileiro foi predominantemente hidrogeológico e por dispersão por meio de paleo-bacias no período de baixo nível do mar.
45

Filogenia do gênero Chironius (Serpentes, Colubridae) baseada em dados morfológicos e moleculares / Phylogeny of the genus Chironius (serpentes, Colubridae) based on morphological and molecular data

Julia Klaczko 15 February 2007 (has links)
Chironius, um dos maiores gêneros da subfamília Colubrinae na América do Sul, inclui 14 espécies, diagnosticadas pela presença de 10 ou 12 fileiras de escamas dorsais no meio do corpo. O gênero apresenta uma distribuição Neotropical, que se estende desde a costa norte de Honduras até o Uruguai e o nordeste da Argentina. Neste trabalho foi realizada uma análise filogenética combinada de 75 caracteres morfológicos e 1397 caracteres moleculares (provenientes das seqüências de dois genes mitocondriais, 12S e 16S, e um gene nuclear, c-mos) pelos métodos de máxima parcimônia e inferência bayesiana. A monofilia do gênero Chironius foi corroborada e os resultados obtidos sugerem que o gênero é dividido em 10 componentes monofiléticos. Os gêneros Drymobius, Leptophis e Dendrophidion são apontados como os mais relacionados à Chironius, corroborando trabalhos anteriores. Chironius laevicollis e C. scurrulus formam o clado mais basal entre as espécies, e sua distribuição restrita a América do Sul sugere que Chironius tenha tido origem neste continente e que posteriormente tenha invadido a América Central através de eventos de dispersão. / Chironius, one of the greatest genera of the Colubrinae subfamily in South America, consists of 14 species, diagnosed by the presence of 10 or 12 rows of dorsal scales in the mid-body. The genus presents a Neotropical distribution extending from the northern coast of Honduras to Uruguay and northeastern Argentina. This study presents a combined phylogenetic analysis of 75 morphological characters and 1397 molecular characters (from the sequences of two mitochondrial genes, 12S and 16S, as well as a nuclear gene, c-mos) by means of Maximum Parsimony and Bayesian Inference. The monophylety of the genus Chironius was corroborated and the obtained results suggest that the genus is subdivided in ten monophyletic components. The genera Drymobius, Leptophis and Dendrophidion come out as the most closely related to Chironius, corroborating previous studies. Chironius laevicollis and C. scurrulus composed the most basal clade among the species. Their distribution is restricted to South America, which suggests that Chironius originated in South America and later invaded Central America through dispersion.
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Filogenia e revisão de Pseudotrimezia (Iridaceae) / Phylogeny and taxonomic revision of Pseudotrimezia (Iridaceae)

Juliana Lovo 14 August 2009 (has links)
Diversos estudos filogenéticos moleculares em Iridaceae confirmam o monofiletismo de Trimezieae. Entretanto, a tribo é pobremente caracterizada e carece de sinapomorfias morfológicas que a sustentem. Por outro lado, o gênero Pseudotrimezia, apesar de morfologicamente bem caracterizado, nunca teve seu monofiletismo investigado. Estudos envolvendo a tribo Trimezieae demonstram que caracteres anatômicos podem contribuir para a taxonomia do grupo além de auxiliar na sua reconstrução filogenética. No presente estudo foram realizados estudos filogenéticos envolvendo caracteres morfológicos e moleculares, separadamente e em análise de evidência total. Foram levantados 50 caracteres morfológicos, incluindo anatomia foliar, em Pseudotrimezia e nos gêneros relacionados, Neomarica e Trimezia. Os caracteres moleculares foram obtidos de três regiões plastidias (trnG, trnH-psbA e trnK) e uma nuclear (ITS). A análise de parcimônia com os dados morfológicos resultou em uma filogenia com Pseudotrimezia monofilético, sem sustentação, enquanto Neomarica e Trimezia emergem como polifiléticos. Assim, os caracteres morfológicos mostraram-se insuficientes para a compreensão da história evolutiva do grupo. A análise de evidência total apresenta Pseudotrimezia monofilético em um clado bem caracterizado morfologicamente sustentado por 10 sinapomorfias homoplásticas. Não obstante, Trimezia e Neomarica emergem agrupados em quatro clados distintos, a maioria sem sustentação, revelando que os gêneros reconhecidos na tribo Trimezieae não correspondem a grupos monofiléticos. As análises filogenéticas fornecem um arcabouço para discutir a sistemática de Pseudotrimezia, gênero endêmico dos campos rupestres da porção mineira da Cadeia do Espinhaço. Apesar de sua distribuição restrita e morfologia floral relativamente uniforme, 24 nomes surgiram desde sua criação em 1945, e muitas das espécies são endêmicas de localidades restritas. É apresentada a revisão de 16 espécies reconhecidas, respectivos mapas de distribuição, ilustrações e chave de identificação / Several molecular phylogenetic studies focusing on Iridaceae contribute to confirm Trimezieae as a monophyletic group. Despite that, the tribe is poorly characterized and lacks morphological synapomorphies as support. On the other hand, Pseudotrimezia is morphologically well characterized, but its monophyly has never been investigated. Anatomical studies carried out with tribe Trimezieae indicates that this kind of data can be a good source for taxonomic and phylogenetic analyses. This study performed phylogenetic analysis using morphological and molecular data, separately and combined in a total evidence approach. Molecular data were obtained from three plastid regions (trnG, trnH-psbA and trnK), and one nuclear (ITS). Fifty morphological characters, including leaf anatomy, were selected within Pseudotrimezia and the related genera Neomarica and Trimezia. Parsimony morphological analysis results in a monophyletic Pseudotrimezia with no support, and, Neomarica and Trimezia aspolyphyletic; therefore, morphological characters were insufficient to help understand the evolutionary history of this group.The total evidence analysis shows Pseudotrimezia monophyletic in a morphologically well-characterized clade, suppported by 10 homoplastic synapomorfies. Nevertheless, Trimezia and Neomarica arise mixed together in four distinct clades, most of them with no support, suggesting that tradicionally recognized genera in the tribe do not correspond to monophyletic groups. Neverthless, phylogenetic analyses provide an important framework for systematic studies of Pseudotrimezia (Iridaceae), an endemic genus from \"campos rupestres\" in Espinhaço Range, Minas Gerais State, Brazil. Despite its restricted distribution and quite uniform morphology, 24 names have been created since the genus was first described in 1945, and many species are endemic of particular localities. The revision of 16 recognized species, their distribution maps, illustrations, and identification key are presented.
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Écologie, Évolution et Développement du genre des plantes carnivores à urnes du genre Nepenthes / Ecology, Evolution and Development of the carnivorous pitcher-plants of the genus Nepenthes

Bonhomme, Vincent 16 December 2010 (has links)
Le genre de plantes carnivores à Nepenthes comporte au moins 120 espèces, réparties dans le sud est asiatique avec les iles de Bornéo et de Sumatra comme centres d'endémisme et de diversité. Ce sont des lianes, dont les feuilles modifiées en urnes comportent un faisceau d'adaptations physicochimiques et morphologiques qui concourent à l'attraction, la capture et la digestion d'arthropodes. La très grande diversité morphologique du genre est couplé e à une diversité fonctionnelle : les mécanismes de rétention sont variables d'une espèce à l'autre. A côté de cette diversité interspécifique, certaines espèces voient la morphologie et le fonctionnement de leurs urnes se modifier au cours de leur ontogénie. Cette thèse fait le lien entre les mécanismes du piégeage et l'écologie de quelques espèces et l'histoire évolutive et de la diversification du genre. / The carnivorous genus encompasses at least 120 species mainly distributed in SE Asia with Borneo and Sumatra recognized as endemism and diversity centers. They are vines whose leaves modified as pitchers exhibit an array of morphological and physicochemical adaptations that compete to the attraction, the capture and the digestion of arthropods. Besides the great morphological diversity the genus comprises a functional diversity exists: retentive mechanisms vary between species and in some species pitcher morphologies and functioning can also change throughout ontogeny. This thesis attempts to describe the trapping mechanisms and the ecology of some species to the evolutionary history of the diversification of the genus.
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Diversité morphologique, génétique, cytogénétique des Mascarocoffea (caféiers des îles de l'océan indien) : évidence d'une origine non africaine des caféiers ? / Morphologic, genetic, cytogenetic diversity of Mascarocoffea : evidence of non african origin

Razafinarivo, Norosoa Josiane 30 May 2012 (has links)
La nouvelle distribution et classification des Coffea (124 espèces Psilanthus incluses, en Afrique, îles de l‟océan Indien (IOI), Inde, Asie du Sud-Est et Australasie) pose la question de leur origine. Des données sont disponibles pour les caféiers africains mais pas pour les Mascarocoffea (caféiers des IOI représentant la moitié des espèces du genre). Les objectifs de cette thèse sont i)- estimer la divergence morphologique, génétique (13 SSR) et génomique des Mascarocoffea, ii)- établir la phylogénie moléculaire du genre (20 COSII) et iii) reconstituer l‟histoire évolutive des caféiers.La diversité morphologique bien que sous forme de continuum, permet la caractérisation de groupements et de stratégies reproductives originales. Les tailles de génome varient de 0,96 à 1,41 pg/2C, avec tendance à l‟augmentation du Nord au Sud-Est de Madagascar.Les nombres moyens d‟allèles par locus et par grande région sont élevés et 20% des allèles totaux sont partagés par ces régions. La phylogénie moléculaire place Psilanthus à la base de l‟arbre et indique une nette divergence entre les Mascarocoffea et les espèces africaines. Il n‟y a pas de structuration hiérarchisée indiquant une divergence indépendante de chaque grand clade.Nos résultats et des données de la littérature nous permettent de proposer un scenario de l‟histoire évolutive des caféiers dont l‟origine est non africaine. Deux centres de diversification primaire sont mis en évidence, situé l‟un en Afrique dans la région Kenya – Ethiopie (à l‟origine de diversifications secondaires vers le Centre, l‟Ouest et l‟Est) et l‟autre dans le Nord Madagascar (à l‟origine des diversifications secondaires à Madagascar et Maurice). / The new classification and repartition of the genus Coffea (124 species including ex-genus Psilanthus native to Africa, Indian Ocean islands (IOIs), India, southeast Asia and Australasia) rises the question on its origin. Genetic and cytogenetic data are available for African species but not for Mascarocoffea (coffees from IOIs including half part of the species). The aims of this thesis were i) to estimate the morphologic, genetic (13 SSRs) and cytogenetic divergence of and among Mascarocoffea; ii) to produce a molecular phylogeny and iii) to reconstruct the coffees evolutionary history.Although the global morphological diversity appears as a continuum, it permits the identification of groupings and obvious specific reproductive strategies. Genomes size varied from 0.96 to 1.41 pg/2C with an increasing global trend from north to southeast Madagascar.Average alleles number per locus is high whatever the region and 20% total alleles are shared by African and IOIs coffees.The molecular phylogeny shows a basal position for Psilanthus, clear divergence between African and IOIs species. Clearly, IOIs clade is not nested within the African. Our results and information from other works permit us to elaborate a new scenario for the evolutionary history of coffees. The centre of origin should be located in India. Then two primary centres of diversification occurred; one in Kenya- Ethiopia, Africa the other in north Madagascar. From these centres, migrations towards centre and west and towards east Africa led to secondary centres of diversification while in Madagascar, migrations towards southeast and towards the other islands led to radiative speciation.
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Filogenia e evolução cariotípica do gênero Philodendron (Araceae), com ênfase para espécies da Amazônia brasileira

VASCONCELOS JUNIOR, Santelmo Selmo de 13 February 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-13T14:16:02Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) 00 Santelmo Vasconcelos Tese Final.pdf: 5907295 bytes, checksum: f9f2150b754187a5591b2d05cd74670d (MD5) / Made available in DSpace on 2016-04-13T14:16:02Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) 00 Santelmo Vasconcelos Tese Final.pdf: 5907295 bytes, checksum: f9f2150b754187a5591b2d05cd74670d (MD5) Previous issue date: 2015-02-13 / CAPES / CNPq / FACEPE / O gênero Philodendron, um dos principais componentes da flora Neotropical, é o segundo maior da família Araceae, contando com aproximadamente 500 espécies e uma enorme diversidade ecológica. Assim como vários outros grupos vegetais da América tropical, ainda há uma grande defasagem de estudos para o gênero, principalmente no que concerne à sistemática filogenética e à evolução cariotípica das espécies de Philodendron. Desta forma, foram realizadas análises de filogenia molecular baseadas em marcadores plastidiais (rpl32-trnL, trnQ-5’-rps16 e trnV-ndhC) e nucleares (ITS), bem como contagens cromossômicas e estimativas do conteúdo de DNA, levando em consideração espécies das principais subdivisões do gênero e dos grupos irmãos. Ao todo, foram realizadas contagens cromossômicas para 48 espécies, sendo 38 novas, assim como uma revisão de todos os números diploides disponíveis, totalizando 69 espécies, onde a maioria (32 spp.) apresentou 2n = 32, seguido de 2n = 34 (20 spp.). Nas análises filogenéticas foi confirmada a hipótese de parentesco dos subgêneros de Philodendron, onde P. subg. Philodendron e P. subg. Pteromischum apareceram como grupos irmãos e P. subg. Meconostigma como a primeira linhagem a divergir, com os três formando um grupo monofilético. Adicionalmente, foram realizadas estimativas de conteúdo de DNA para 163 acessos, incluindo 108 espécies de Philodendron, bem como 17 espécies de grupos relacionados, onde foi observada uma grande diversidade no tamanho genômico no gênero, variando entre 2,48 e 7,58 pg, indicando uma maior importância da amplificação/eliminação de DNA repetitivo para a evolução cariotípica do grupo, em vez das alterações drásticas nos números cromossômicos, como poliploidizações. / Philodendron, one of the most important components of the Neotropical flora, is the second largest genus within Araceae, which presents approximately 500 species and a huge ecologic diversity. As well as it is observed for other plant groups from tropical America, one can still note a remarkable lack of studies on the evolution of the genus, mainly regarding to phylogenetic systematics and karyotype evolution analyses among Philodendron species. Thus, a molecular phylogeny based on chloroplast (rpl32-trnL, trnQ-5’-rps16 e trnV-ndhC) and nuclear (ITS) markers, as well as chromosome counts and DNA C-value estimations were performed, with species from the main subdivisions within the genus and sister groups. Fortyeight chromosome numbers were described herein, from which 38 were new. Besides, all the available diploid numbers were revised, totalizing 69 species with known chromosome numbers, from which the major part (32 spp.) presented 2n = 32, followed by 2n = 34 (20 spp.). In the phylogenetic analyses, the morphological hypothesis of relationship among the subgenera was confirmed, in which P. subg. Philodendron and P. subg. Pteromischum were recovered as sister groups and P. subg. Meconostigma as the first diverging lineage of the monophyletic group. In addition, DNA content estimations were performed for 163 accessions, including 108 species from Philodendron and 17 from related groups, in which a wide variation of genome sizes were observed, ranging from 2.48 to 7.58 pg. Therefore, it was indicated that the mechanisms of amplification/elimination of repetitive DNA might be more important for the karyotype evolution within the group, in comparison to drastic numeric changes in chromosome numbers such as polyploidization.
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Ontogênese da região da axila foliar e filogenia molecular de Didiereaceae: a história de um caráter e suas implicações filogenéticas em Portulacineae / Axillary bud ontogenesis and molecular phylogeny of Didiereaceae: a character history and its phylogenetic implications in Portulacineae

Mario Albino de Oliveira Neto 29 April 2014 (has links)
Recentes análises filogenéticas, baseadas em dados moleculares, indicaram que Didiereaceae s.s. é filogeneticamente relacionada a gêneros tradicionalmente pertencentes à Portulacaceae s.l.. Sendo incluídos os gêneros Ceraria, Portulacaria e Calyptrotheca em Didiereaceae e essa dividida em três subfamílias: Didieroideae (11 espécies), Portulacarioideae (7 espécies) e Calyptrothecoideae (1espécie). Análises moleculares apresentaram alto suporte para o monofiletismo da família e circunscrição das três subfamílias, contudo, nenhuma dessas análises elucidou completamente as relações entre os gêneros. Com a expansão de sua circunscrição, a família se tornou mais heterogênea, surgindo assim, a necessidade da investigação de características para o estabelecimento de sinapomorfias ou para corroborar suas relações dentro de Portulacineae. Diante disso, o presente trabalho realizou análises de Inferência Bayesiana e Máxima Parcimônia para sete sequências diferentes do DNA do cloroplasto, trnA-trnB, trnL-trnF, trnT-trnL, trnS-trnG, trnQUUG-rps16, rps16 e rpl16, para todas as 19 espécies de Didiereaceae e investigou a ontogênese foliar e da região de sua axila para Didieroideae e Portulacarioideae. Os resultados das análises filogenéticas corroboraram o monofiletismo da família e de suas três subfamílias, além de elucidar as relações internas em Didieroideae e Portulacarioideae. Os dois gêneros de Portulacarioideae, Portulacaria e Ceraria, não são monofiléticos e as espécies de Ceraria foram transferidas para Portulacaria. Também foi caracterizado o desenvolvimento dos diferentes padrões de variações morfológicas da folha e das folhas modificadas em espinhos e profilos. A partir dos resultados do desenvolvimento e da filogenia molecular, foi feita uma análise de reconstrução da região da axila foliar para o ancestral de Didiereaceae, que indicou a presença de braquiblastos portadores de profilos na axila foliar do ancestral comum. Como consequência, foram estabelecidas homologias entre esses profilos e os profilos de Talinaceae e espinhos de Cactaceae / Recent phylogenetic analysis, based on molecular data, indicated that Didiereaceae s.s. is phylogenetic related to former Portulacaceae s.l. genera. The genera Ceraria, Portulacaria and Calyptrotheca were included in Didiereaceae and the family was divided in three subfamilies: Didieroideae (11 species), Portulacarioideae (7 species) and Calyptrothecoideae (1specie). Molecular analyses presented high statistical support to the monophyletism of the Didiereaceae and its division in three subfamilies, however, none of these analyses elucidated the relations among genera. With the expansion of its circumscription, the family became rather heterogenic, resulting in the need to investigate characteristics to the establishment of synapomorphies to the family or corroborate its relations inside Portulacineae. Therefore, we performed Bayesian Inference and Maximum Parsimony analyses for seven different chloroplast DNA regions, trnA-trnB, trnL-trnF, trnT-trnL, trnS-trnG, trnQUUG-rps16, rps16 and rpl16, for all 19 species of Didiereaceae and investigated the leaf and leaf axil region ontogenesis for Didieroideae and Portulacarioideae. Our analyses corroborated the monophyly of the Didiereaceae and of its three subfamilies and elucidated internal relationships between the Didieroideae and the Portulacarioideae. The two genera of the Portulacarioideae, Portulacaria and Ceraria, are not monophyletic and the 5 accepted species for Ceraria are transferred to Portulacaria. Also, the ontogenesis for different morphological patterns of leaf and spines and prophyll were characterized. Based on the ontogenetical results and the molecular phylogeny, was made the reconstruction to the ancestor character for the leaf axil of Didiereaceae. This analysis indicated the presence of brachyblasts bearing prophylls in the leaf axil of the common ancestor. As a consequence, homologies between these prophylls and Talinaceae prophylls and Cactaceae spines were established

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