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QUESTIONS: Studies on bryophyte and lichen diversity patterns along elevational gradients are scarce, although this approach can serve as space‐for‐time substitution to predict diversity changes because of climate warming. Therefore, we investigated bryophytes and macrolichens in disturbed and undisturbed stands along an elevational gradient in the unique laurel forest of Madeira island by addressing the following questions: (a) how does the species richness of functional‐taxonomic bryophyte and macrolichen groups differ with elevation; (b) how is the species richness of these groups affected by disturbances? LOCATION: UNESCO World Natural Heritage site laurel forest of Madeira island (Madeira, Portugal). METHODS: We analyzed species richness of bryophytes and macrolichens in 92 plots in response to elevation and to disturbances. RESULTS: Bryophyte species richness showed a mid‐elevational peak, while macrolichen richness increased with elevation. Disturbed plots harbored on average 20% less bryophyte and macrolichen species than undisturbed plots. CONCLUSIONS: The laurel forest of Madeira island is a bryophyte and lichen diversity hotspot. Our findings indicate future biodiversity threats by changing environmental conditions. This calls for the need for a strict protection status of the laurel forest on Madeira island to minimize human‐related disturbances, for the development of management measures that could mitigate climate change effects by maximizing habitat suitability and for the implementation of species conservation programs to prevent future extinctions, in particular of endemic species.

The ‘Rand flora’ is a biogeographical disjunction which refers to plant lineages occurring at the margins of the African continent and neighbouring oceanic archipelagos. Here, we tested whether the phylogeographical pattern of Exormotheca pustulosa Mitt. was the result of vicariance induced by past climatic changes or the outcome of a series of recent long-distance dispersal events. Two chloroplast markers (rps4-trnF region and psbA-trnH spacer) and one nuclear marker (ITS2) were analysed. Phylogenetic and phylogeographical relationships were inferred as well as divergence time estimates and ancestral areas. Exormotheca possibly originated in Eastern Africa during the Late Oligocene/Early Miocene while Exormotheca putulosa diversified during the Late Miocene. Three main E. pustulosa groups were found: the northern Macaronesia/Western Mediterranean, the South Africa/Saint Helena and the Cape Verde groups. The major splits among these groups occurred during the Late Miocene/Pliocene; diversification was recent, dating back to the Pleistocene. Climate-driven vicariance and subsequent long-distance dispersal events may have shaped the current disjunct distribution of E. pustulosa that corresponds to the Rand Flora pattern. Colonization of Macaronesia seems to have occurred twice by two independent lineages. The evolutionary history of E. pustulosa populations of Cape Verde warrants further study., This work was supported by Fundação para a Ciência e Tecnologia, Portugal (Project PTDC/AGR-FOR/3427/2014). We thank the LISU, E and PRE herbaria for providing material for the development of this work. We also thank Vera Nunes for her support in the laboratory. J.P. was funded by the Ministerio de Economía y Competitividad through the Ramón y Cajal Program (RYC-2016-20506), and Marie Sklodowska-Curie COFUND, Researchers’ Night and Individual Fellowships Global (MSCA grant agreement No. 747238, ‘UNISLAND’). We thank the anonymous reviewers for their helpful comments.

The Madeiran laurel forest (Laurisilva) is a subtropical forest with a very rich bryophyte flora and is considered as one of the most important remnants of the evergreen laurel forest from the Tertiary period. The effect of the laurel forest tree species on the epiphytic bryophyte species richness and composition in Madeira Island was studied in 40 sites. A total of 160 trees, belonging to 19 different tree species were assessed in the laurel forest. For subsequent analyses, we focused on seven tree species, for which at least nine individuals were sampled. A total of 137 trees from 40 sites were thus available for statistical analyses. We recorded 110 epiphytic bryophyte taxa (59 species and one variety of mosses and 50 liverworts). Accumulation curves showed clear differences in bryophyte species richness between the different tree species, with typical laurel forest tree species harboring more bryophytes. Tree species also had highly significant effects on species density (mean species richnes...

The volatiles isolated by distillation - extraction from 48 samples of seven liverwort Radula species collected on Azores and Madeira archipelagos and mainland Portugal, as well as one from Switzerland, were analysed by GC and GC-MS. Cluster analysis of the volatiles composition resulted in two major clusters. The chemically very diverse cluster I included the oil samples of Radula aquilegia from Madeira, R. jonesii, R. holtii, R. nudicaulis, R. lindenbergiana as well as R. complanata from Switzerland. Cluster II was characterized by high relative amounts of several sesquiterpenes and included the oil samples of R. aquilegia from the Azores as well as R. carringtonii and R. wichurae. 3-Methoxy bibenzyl was the major oil component from R. complanata and R. lindenbergiana. Except for R. aquilegia and the closely related species R. complanata and R. lindenber- giana, the cluster analysis allows distinction of all studied species, indicating the chemotaxonomical value of the volatile oil characters. Copyright © 2009 John Wiley & Sons, Ltd.

Mestrado em Matemática - Ensino Nos últimos anos tem-se vindo a assistir a um avanço extraordinário da Genética com a descodificação do código genético completo de um número cada vez maior de espécies. Usando uma terminologia matemática, pode-se dizer que a molécula de DNA, de qualquer organismo, é constituída por pares de sequências complementares de símbolos retirados de um alfabeto de quatro símbolos (os nucleótidos). Para cada sequência, e dependendo do contexto de interesse, podem ser realizadas contagens daqueles símbolos e daí extrair informações estatísticas relevantes na identificação de regras que governam as sequências de DNA e, consequentemente, a tradução do mRNA pelo ribossoma. O grupo de Bioinformática da Universidade de Aveiro tem vindo a investigar o sequenciamento de codões (tripletos de nucleótidos) em zonas codificantes do DNA de organismos de qualquer domínio da Vida: Archaea, Eukarya e Bacteria. Um dos objectivos práticos da presente dissertação é contribuir para o avanço dessa investigação analisando propriedades associadas aos pares de codões iguais e aos codões raros. Para tal, cento e dezanove espécies dos três domínios da Vida são aqui consideradas. Nesta dissertação estudam-se, assim, metodologias estatísticas apropriadas à análise de dados discretos de populações Binomiais, Multinomiais e de Poisson, sendo consideradas diferentes propostas de inferir os parâmetros das distribuições. Analisam-se e comparam-se ainda, vários procedimentos que garantem a significância global fixada na realização de testes simultâneos. Este estudo permitiu estabelecer diferentes formas de identificar pares de codões problemáticos no sequenciamento do DNA em zonas codificantes. De forma ainda a contemplar a componente Ensino, foram criadas aplicações interactivas com o propósito de dinamizar o interesse pelo estudo do Tema: Probabilidades e Análise Combinatória, do actual programa do 12º ano de escolaridade. Nessas aplicações mostram-se representações gráficas de funções de massa de probabilidade das distribuições Binomial, Hipergeométrica e de Poisson e tem como objectivo que o aluno/utilizador, de modo intuitivo, estabeleça distribuições limite para as distribuições discretas; nomeadamente, a convergência da distribuição Binomial à Normal, da Hipergeométrica à Binomial e desta à distribuição de Poisson. ABSTRACT: In the past few years we have been assisting a remarkable development of Genetic with the decoding of the genetic code for a larger number of species. Using a mathematic terminology one can state that the DNA molecule is defined by pairs of complementary sequences of four symbols (nucleotides). Several estimating can be made for these sequences depending on the objective of the studies. It can provide new insight on the rules that govern the DNA sequences and so the mRNA decoding accuracy by the ribosome. The Aveiro University Bioinformatics group has been investigating the evolution of codons (nucleotides triplets) context on a genome wide scale for species of any Life domain: Archaea, Eukarya and Bacteria. One of the main practical aims of this work is to contribute for the progress of these investigations, by the analysis of associated properties to equal pairs of codons and rare codons. For that matter a hundred and nineteen species from all the three domains were considerer in this study. In this work, different specifics statistical methodologies to discrete data from Binomial, Multinomial and Poisson populations were studied, by analyzing several approaches to infer their parameters. Also, several procedures were analysed and compared, that guarantee the global significance of performing multiple tests. These studies allowed us to establish different forms in the identification of problematic codon pairs in coding sequences of genome. The educational component was also considered in this work by the creation of interactive applications in contents of Mathematic discipline in Secondary school. These applications show graphical representations of the probability mass function for discrete probability distributions herein studied and provide an easy way for students/users to analyse their limiting distributions.

The essential oils isolated from twigs of Juniperus cedrus Webb & Berth. grown on Madeira were analysed by GC, GC-MS and 13C-NMR. The oils consisted mainly of monoterpene hydrocarbons (53.1-87.8%), the main ones being alpha-pinene (19.6-55.3%), limonene (17.3-32.7%) and Delta-3-carene (5.5-15.7%). The sesquiterpenoid fraction (4.1-22.3%) was dominated by E-caryophyllene (1.6-7.4%), while sandaracopimaradiene (0.1-6.1%), isoabienol (0.5-1.3%) and trans-totarol (0.4-2.2%) were the main diterpenoids (2.2-11.9%). Oct-1-en-3-ol (1.0-2.2%) was the major constituent of the non-terpenic fraction (1.3-2.7%). The composition of our oil samples differed to some extent from that reported for J. cedrus oil grown on the Canary Islands. Copyright © 2002 John Wiley & Sons, Ltd. http://dx.doi.org/10.1002/ffj.1061

The peculiar disjunction between Macaronesia and Australasia of the morphologically isolated pleurocarpous moss genus Echinodium is one of the most prominent questions in bryology. Echinodium as traditionally circumscribed comprises six extant species, four restricted to the Macaronesian archipelagos and two confined to the Australasian/Pacific regions. Molecular phylogenetic analyses based on plastid trnLUAA intron and nuclear ribosomal ITS sequences indicate that Echinodium is polyphyletic and split into three groups. Three of the four Macaronesian species (E. spinosum and the single island endemics E. renauldii and E. setigerum) are closely related to each other and treated as Echinodium s.str. (Echinodiaceae). Further clarification of the relationships of Echinodium s.str. with Orthostichella, a segregate of Lembophyllaceae, is needed. The remaining Macaronesian species, E. prolixum, is transferred to Isothecium (Lembophyllaceae); this systematic position is also strongly supported by leaf characters. The two Australasian species, E. hispidum and E. umbrosum, are molecularly unrelated to the Macaronesian species and are transferred to Thamnobryum in the Neckeraceae. While the molecular data suggest that the peculiar distribution pattern of ‘Echinodium’ is an artefact, the striking morphological similarity observed in Macaronesian and Australasian species cannot be dismissed. Possible explanations are: (i) parallel morphological evolution of the ‘Echinodium habit’ in Macaronesia and Australasia, or (ii) retention of a set of plesiomorphic characters in non-related groups in relict habitats, the Macaronesian laurel forest and the austral temperate rain forests, respectively. Of these hypotheses, the evolutionary parallelism hypothesis seems more plausible for several reasons, which are discussed.