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1	Devonian origin and Cenozoic radiation in the clubmosses (Lycopodiaceae) Testo, Weston 01 January 2018 (has links) Together with the heterosporous lycophytes, the clubmoss family (Lycopodiaceae) is the sister lineage to all other vascular land plants. Given the family’s important position in the land-plant phylogeny, studying the evolutionary history of this group is an important step towards a better understanding of plant evolution. Despite this, little is known about the Lycopodiaceae, and a well-sampled, robust phylogeny of the group is lacking. The goal of this dissertation is to resolve the relationships among evolutionary lineages in the Lycopodiaceae and provide insight into the timing and drivers of diversification in the family. First, to place the evolution of the family within a global and historical context, I generated a densely sampled, time-calibrated phylogeny of the family. I sampled 50% of the estimated 400 extant species in the Lycopodiaceae and used eight fossils to calibrate the age of major divergence events in the family and across the land-plant phylogeny. Further, we used a probabilistic biogeographic model to infer the historical biogeography of the family. Together, these analyses indicate that the Lycopodiaceae originated in the late Devonian, began its early diversification in the Carboniferous, and accumulated much of its extant diversity during the Cenozoic. From a geographical perspective, major cladogenesis events in the family’s history appear to be linked to the breakup of the Pangaean and Gondwanan supercontinents, with long-distance dispersal playing a role in the establishment of younger evolutionary lineages. Second, I examined the drivers of diversification in the species-rich genus Phlegmariurus in the Neotropics. This clade includes an estimated 150 species and is most diverse in high-elevation habitats in the tropical Andes of South America. Using a time-calibrated phylogeny of the group and species distribution and niche data, I demonstrate a strong positive association between lineage diversification rates and the mean elevation of species’ distributions as well as a strong negative correlation between diversification rates and the size of species’ ranges. Further, we employ a paleoelevation-dependent diversification model to test for an association between the uplift of the Andes and diversification in the clade and demonstrate that speciation rates in Neotropical Phlegmariurus are positively associated with increasing elevations in the Andes. Third, I use a phylogenetic framework to test the monophyly of morphology-based species groups in Neotropical Phlegmariurus. I demonstrate that most groups are not monophyletic, and that convergent evolution is widespread in the genus. We use ancestral character-state reconstruction methods for six morphological traits to elucidate patterns of trait evolution and to circumscribe new species groups. A total of eleven new monophyletic species groups are proposed and defined. evolution lycophytes plant Systems Biology
2	Phylogeny of Phlegmariurus (Lycopodiaceae) focusing on Brazilian endemic species / Filogenia de Phlegmariurus (Lycopodiaceae) com ênfase em espécies endêmicas do Brasil Gissi, Danilo Soares 20 March 2017 (has links) Phlegmariurus is the most abundant genus of Lycopodiaceae in Brazil with 40 species, 24 of which are endemic, occurring mainly in the Atlantic Rainforest and Rocky Fields (“Campos Rupestres”) in the Espinhaço range. Some phylogeny works with the group had already been carried out, but not including a representative sample of the Brazilian species. Thus, we performed a molecular phylogeny of Phlegmariurus species endemic in Brazil using three molecular markers of cpDNA. Phlegmariurus showed to be monophyletic, including two clades, one Neotropical and another Paleotropical. All the Brazilian species sampled appeared in the Neotropical clade. The endemic species appeared in several clades alongside Andean species. Epiphytism and the microphylls differentiation were optimized at the obtained clade and they appeared several times in the evolutionary history of the group / Phlegmariurus é o gênero mais abundante de Lycopodiaceae no Brasil com 40 espécies, sendo 24 destas endêmicas, ocorrendo principalmente na Mata Atlântica e Campos Rupestres da Cadeia do Espinhaço. Alguns trabalhos de filogenia com o grupo já haviam sido realizados, contudo sem incluir uma amostragem representativa das espécies brasileiras. Dessa forma, realizamos a filogenia molecular das espécies de Phlegmariurus endêmicas do Brasil utilizando três marcadores moleculares de cpDNA. Phlegmariurus se mostrou monofilético, incluindo dois clados, um Neotropical e outro Paleotropical. Todas as espécies brasileiras amostradas apareceram no clado neotropical. As espécies endêmicas apareceram em vários clados em meio as espécies andinas. O epifitismo e a diferenciação dos microfilos foram otimizados nos clados obtidos e indicaram que essas características surgiram várias vezes na história evolutiva do grupo Huperzia Huperzia Licófitas Lycophytes Pteridófitas Pteridophytes
3	Phylogeny of Phlegmariurus (Lycopodiaceae) focusing on Brazilian endemic species / Filogenia de Phlegmariurus (Lycopodiaceae) com ênfase em espécies endêmicas do Brasil Danilo Soares Gissi 20 March 2017 (has links) Phlegmariurus is the most abundant genus of Lycopodiaceae in Brazil with 40 species, 24 of which are endemic, occurring mainly in the Atlantic Rainforest and Rocky Fields (“Campos Rupestres”) in the Espinhaço range. Some phylogeny works with the group had already been carried out, but not including a representative sample of the Brazilian species. Thus, we performed a molecular phylogeny of Phlegmariurus species endemic in Brazil using three molecular markers of cpDNA. Phlegmariurus showed to be monophyletic, including two clades, one Neotropical and another Paleotropical. All the Brazilian species sampled appeared in the Neotropical clade. The endemic species appeared in several clades alongside Andean species. Epiphytism and the microphylls differentiation were optimized at the obtained clade and they appeared several times in the evolutionary history of the group / Phlegmariurus é o gênero mais abundante de Lycopodiaceae no Brasil com 40 espécies, sendo 24 destas endêmicas, ocorrendo principalmente na Mata Atlântica e Campos Rupestres da Cadeia do Espinhaço. Alguns trabalhos de filogenia com o grupo já haviam sido realizados, contudo sem incluir uma amostragem representativa das espécies brasileiras. Dessa forma, realizamos a filogenia molecular das espécies de Phlegmariurus endêmicas do Brasil utilizando três marcadores moleculares de cpDNA. Phlegmariurus se mostrou monofilético, incluindo dois clados, um Neotropical e outro Paleotropical. Todas as espécies brasileiras amostradas apareceram no clado neotropical. As espécies endêmicas apareceram em vários clados em meio as espécies andinas. O epifitismo e a diferenciação dos microfilos foram otimizados nos clados obtidos e indicaram que essas características surgiram várias vezes na história evolutiva do grupo Huperzia Licófitas Pteridófitas Huperzia Lycophytes Pteridophytes
4	Patterns and biological implications of DNA content variation in land plants Bainard, Jillian D. 21 October 2011 (has links) DNA content varies significantly over land plants, and is known to correlate with various aspects of plant form and function. In the present study, two measures of DNA content were examined in taxa across the land plant phylogeny: genome size (or C-value) and endopolyploidy (or endoreduplication index, EI). Additionally, the relationships between DNA content and various morphological and ecological traits were assessed. DNA content was determined for 64 liverwort species from 33 families. There was a large range in 1C-values from 0.27 to 20.46 pg, but no endopolyploidy was observed. There was no correlation between genome size and breeding system (monoecy vs. dioecy). Genome size and degree of endopolyploidy were determined for 74 moss species from 21 families. Genome sizes were constrained in this group, with 1C-values ranging from 0.25 to 1.21 pg. Endopolyploidy was high in all species except from the Sphagnaceae. Additionally, 1C-value was negatively correlated with desiccation tolerance but was not correlated with breeding system. DNA content variation was determined in 31 monilophyte (fern) species (including three horsetails) and 6 lycophyte (clubmoss) species. There was a wide range in 1C-values from 2.79 to 26.90 pg, and there was no indication of endopolyploidy in any of the species. Multivariate analyses were used to explore the relative contribution of traits and phylogenetic placement to DNA content varation in 41 angiosperm species. Six measures of DNA content (2C-value, 1Cx-value, leaf EI, stem EI, petal EI and root EI) were assessed. Phylogeny explained more of the variation observed in the six measures of DNA content than 21 ecological and morphological traits. However, many of the traits were able to explain some of the variation in DNA content, both with and without phylogeny included as a covaraite. One trait that was consistently correlated with DNA content was the association with arbuscular mycorrhizal (AM) fungi. In a controlled experiment, the EI in root cells colonized by AM fungi significantly increased compared to non-mycorrhizal plants. This thesis increases our knowledge regarding the extent and significance of variation in DNA content in land plants. Genome size Endopolyploidy Bryophytes Lycophytes Monilophytes DNA content Endoreduplication Liverworts Mosses Land plant evolution Angiosperms
5	Spikemoss patterns : Systematics and historical biogeography of Selaginellaceae / Mosslummermönster : Systematik och historisk biogeografi hos Selaginellaceae Weststrand, Stina January 2016 (has links) Selaginellaceae, spikemosses, is a heterosporous plant family belonging to the lycophytes. With an estimated age of some 350 million years, the family is historically important as one of the oldest known groups of vascular plants. Selaginellaceae is herbaceous with a worldwide distribution. However, the majority of the ca. 750 species in the single genus Selaginella are found in the tropics and subtropics. This thesis aims at elucidating the systematics and historical biogeography of Selaginellaceae. The evolutionary relationships of the family were inferred from DNA sequence data (plastid and single-copy nuclear) of one-third of the species richness in the group. Attention was paid to cover the previously undersampled taxonomic, morphological, and geographical diversity. Morphological features were studied and mapped onto the phylogeny. The results show an overall well-supported phylogeny and even more complex morphological patterns than previously reported. Despite this, many clades can be distinguished by unique suites of morphological features. With the phylogeny as a basis, together with the thorough morphological studies, a new subgeneric classification with seven subgenera, representing strongly supported monophyletic groups, is presented for Selaginella. By mainly using gross morphological features, easily studied by the naked eye or with a hand lens, the intention is that the classification should be useful to a broader audience. During the work with species determinations, it was revealed that the correct name for an endemic Madagascan Selaginella species is S. pectinata Spring, not S. polymorpha Badré as previously proposed. The robust phylogeny of Selaginellaceae allowed for a historical biogeographical analysis of the group. A time-calibrated phylogeny, together with extant species distribution data, formed the basis. The results show pre-Pangean diversification patterns, Gondwanan vicariance, and more recent Cenozoic long-distance dispersals. The many inferred transoceanic dispersals during the last 50 million years are surprising considering Selaginella’s large megaspores that are thought to have a negative effect on dispersal. In conclusion, this thesis presents a well-founded hypothesis of the evolutionary history of Selaginellaceae including its phylogeny, morphology, and historical biogeography. The thesis forms a firm basis for further studies on Selaginellaceae in particular, and gives us a better understanding of early land plant evolution in general. classification historical biogeography lycophytes nomenclature phylogeny Selaginella Selaginellaceae systematics fylogeni historisk biogeografi klassifikation lummerväxter nomenklatur Selaginella Selaginellaceae systematik
6	Diversity and evolution of pteridophytes, with emphasis on the Neotropics / Diversität und Evolution von Pteridophyten, mit besonderer Berücksichtigung der Neotropen Lehnert, Marcus 04 July 2007 (has links) No description available. 580 Pflanzen (Botanik) Mathematics and Computer Science Farne Bärlappgewächse Biogeographie Neotropen Südamerika Bolivien Ecuador Purdiaea Alsophila Cyathea Melpomene epiphytisch terrestrisch Höhenzonierung Mykorrhiza Ferns lycophytes biogeography Neotropics South America Bolivia Ecuador Purdiaea Alsophila Cyathea Melpomene epiphytic terrestrial altitudinal vegetation scheme mycorrhiza 42.25 42.27 42.44 42.53 WL 000: Biogeographie {Biologie} WWL 000: Farne, Pteridophyta {Botanik}

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