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Effects of dispersal and local dynamics on spider diversity (Araneae) in an old field systemFrost, Carol M., January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2009/06/23). Includes bibliographical references.
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The isolation, identification and characterisation of bioactive compounds from plants used in traditional medicineMackenzie, Fiona L. January 1998 (has links)
No description available.
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Cartographie récente et écologie du nerprun bourdaine en EstrieLabonte, Joanie 05 1900 (has links)
Le nerprun bourdaine (Rhamnus frangula L.) est une espèce exotique qui envahit plusieurs régions du sud du Québec, et plus particulièrement la région administrative de l'Estrie. Actuellement, on connaît encore peu l'écologie de l'espèce dans le contexte québécois et il n’existe pas de portrait d’ensemble de sa distribution dans les forêts tempérées de cette région. Dans ce contexte, le premier objectif du projet était de cartographier par télédétection la distribution du nerprun bourdaine dans deux secteurs de l'Estrie. Un second objectif était d'évaluer les variables environnementales déterminantes pour expliquer le recouvrement de nerprun bourdaine.
La phénologie du nerprun bourdaine diffère de celle de la plupart des espèces indigènes arborescentes puisque ses feuilles tombent plus tard en automne. Cette caractéristique a permis de cartographier, par démixage spectral, la probabilité d'occurrence du nerprun bourdaine grâce à une série temporelle d'images du capteur OLI de Landsat 8. Le recouvrement du nerprun bourdaine a été calculé dans 119 placettes sur le terrain. La cartographie résultante a montré un accord de 69% avec les données terrain. Une image SPOT-7, dont la résolution spatiale est plus fine, a ensuite été utilisée, mais n’a pas permis d'améliorer la cartographie, puisque la date d’acquisition de l’image n’était pas optimale dû à un manque de disponibilité.
Concernant le second objectif de la recherche, la variable la plus significative pour expliquer la présence de nerprun bourdaine était la densité du peuplement, ce qui suggère que l’ouverture de la couverture forestière pourrait favoriser l’envahissement. Néanmoins, les résultats tendent à démontrer que le nerprun bourdaine est une espèce «généraliste» qui s’adapte bien à plusieurs conditions environnementales. / Glossy buckthorn (Rhamnus frangula L.) is an exotic species invading many areas in southern of Quebec, particularly in the Eastern Townships. Currently, we do not know very much about the species ecology and no thorough study of its distribution in temperate forest has been performed. Therefore, the first objective of the project was to map the spatial distribution of glossy buckthorn in two areas of the Eastern Townships, using remote sensing techniques. The second objective was to evaluate the environmental variables, or predictors, best explaining the presence of glossy buckthorn.
The phenology of glossy buckthorn differs from most of the indigenous tree species found in this area because its leaves fall later in autumn. This characteristic allowed to map, using spectral unmixing, the probability of occurrence of glossy buckthorn, with temporal Landsat 8 (OLI) imagery data series. Glossy buckthorn coverage was calculated on 119 plots on the field. The resulting maps showed an agreement of 69% with field data. A SPOT-7 image, which has a finer resolution than Landsat 8 (OLI), was then used but it did not improve the quality of the map, since its acquisition date was not optimal, due to a lack of availability.
Concerning the second objective of the research, the best variable explaining the presence of glossy buckthorn was stand density, which leads to believe that forest cover openings could ease the establishment of buckthorn. However, the results tend to show that glossy buckthorn is a generalist species, easily adapting to various environmental conditions.
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Perfil antioxidante e efeito dos extratos, frações e das antraquinonas crisofanol, emodina e fisciona de Rhamnus sphaerosperma var. pubescens sobre a viabilidade celular e estresse oxidativo em células tumorais de colo uterino e carcinoma oral / Antioxidant profile and effect of extracts, fractions and anthraquinones chrysophanol, emodin and physcion from Rhamnus sphaerosperma var. pubescens on cell viability and oxidative stress in uterine tumor cells and oral squamous carcinoma cellsMoreira, Thais Fernanda 25 November 2016 (has links)
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Previous issue date: 2016-11-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os produtos naturais apresentam imensa diversidade estrutural, característica útil para alcançar alvos moleculares específicos importantes para a terapia de diversas doenças, contribuindo assim para a ampliação do arsenal farmacológico. Como observado para o gênero Rhamnus, a espécie vegetal Rhamnus sphaerosperma var. pubescens, nativa no Brasil, pode apresentar um grande potencial químico e farmacológico; popularmente é conhecida como “fruto-de-pombo”, com poucos estudos relatando suas propriedades. Tem composição rica em compostos antraquinônicos, onde já foram identificados crisofanol, fisciona e emodina. Os objetivos deste estudo foram verificar o potencial antioxidante via estudo da capacidade de captura sobre espécies reativas de oxigênio e nitrogênio, assim como a capacidade de indução de morte celular dos extratos, frações e antraquinonas isoladas de Rhamnus sphaerosperma var. pubescens (Rhamnaceae) em células tumorais de colo uterino com e sem o genoma do vírus HPV (SiHa e C33-A, respectivamente), e carcinoma oral de células escamosas (HSC-3). A antraquinona emodina apresentou a melhor capacidade de captura sobre as espécies NO• e O2 •- em relação as demais antraquinonas e extratos brutos. No ensaio de captura sobre o HOCl/OCl- todas as amostras foram efetivas, sendo os extratos brutos com melhor atividade, e dentre as antraquinonas, o crisofanol apresentou maior efetividade. Nenhuma amostra demonstrou capacidade na captura do H2O2. As antraquinonas emodina e fisciona demonstraram efeito citotóxico sobre as linhagens celulares SiHa, C33-A, HSC-3 e HaCaT, com morte celular mista (apoptose e necrose), a qual ocorre de maneira independente de caspases, constatada nos ensaios citomorfológico de exclusão por fluorocromos, anexina-V e avaliação da atividade de capsase-3. O crisofanol não apresentou citotoxicidade. Emodina, fisciona e o extrato bruto promoveram aumento do estresse oxidativo intracelular, uma vez que foi observado aumento de espécies reativas ao ácido tiobarbitúrico (TBARS) e aumento de danos ao DNA como observado nos ensaios de micronúcleo e cometa. As amostras foram capazes de promover supressão da via PI3K/AKT, diminuindo os níveis de fosforilação de AKT: a emodina apresenta melhor atividade e ação apenas sobre as linhagens tumorais SiHa, C33-A e HSC-3; fisciona e extrato bruto apresentaram este efeito sobre as linhagens HSC-3 (tumoral) e HaCaT (não tumoral). Estes dados sugerem que o mecanismo de indução de morte promovido pelas antraquinonas emodina e fisciona, assim como pelo extrato bruto de Rhamnus sphaerosperma var. pubescens, pode ser mediado pelo aumento do estresse oxidativo intracelular, danos ao DNA e também supressão da via PI3K/AKT, importante para a sobrevivência celular. / Natural products have immense structural diversity, useful feature to achieve specific molecular targets in cancer treatment, and thus contribute to the expansion of the therapeutic arsenal. As notorious for the Rhamnus genus, plant species Rhamnus sphaerosperma var. pubescens, native in Brazil may present a great chemical and pharmacological potential; It is popularly known as the Fruto-de-pombo, with few studies reporting its properties. This species has rich composition with anthraquinones, which have been identified: chrysophanol, physcion and emodin. The objectives of this study were to verify the capture capability of reactive species of oxygen and nitrogen, as well as cell death inducing ability of the extracts, fractions and isolated anthraquinones of Rhamnus sphaerosperma var. pubescens (Rhamnaceae) in cervical tumor cells with and without the genome of HPV virus (SiHa and C33-A, respectively), and oral squamous cell carcinoma (HSC-3). The anthraquinone emodin showed the best capture capability of the species NO• and O2 •- compared with other anthraquinones and crude extracts. In the scavenge assay of HOCl / OCl- all samples were effective, and the crude extracts showed better activity and chrysophanol showed better effectiveness among anthraquinones. No samples demonstrated ability in capturing the H2O2. The anthraquinones emodin and physcion demonstrated cytotoxic effect on the cell lines SiHa, C33-A, HSC-3 and HaCaT with mixed cell death (apoptosis and necrosis), independent of caspases pathway, detected in cytomorphological test with fluorochromes exclusion, annexin-V and evaluation of capsase-3 activity. The chrysophanol was not cytotoxic in these assays. Emodin, physcion and the crude extract promoted increased intracellular oxidative stress, verified by thiobarbituric acid reactive species assay (TBARS), and an increase of DNA damage as observed in the micronucleus test. Further, these samples were capable of promoting the supression of PI3K/AKT, reducing levels of activation (phosphorylation) of AKT. In this parameter, emodin showed activity only on the tumor cell lines (SiHa, C33-A and HSC-3), on the other hand, physcion and crude extract showed this effect on HSC-3 and HaCaT cell lines. Therefore, the death induction mechanism promoted by emodin, physcion and crude extract of this plant species should be mediated by an increase of the intracellular oxidative stress, DNA damage, and suppression of the PI3K/AKT important for cell survival. / CAPES
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SYSTEMATICS, TAXONOMY AND BIOGEOGRAPHY OF THE COSMOPOLITAN AND FOSSIL-RICH BUCKTHORN FAMILY (RHAMNACEAE JUSS.)Hauenschild, Frank 30 November 2018 (has links)
My thesis combines taxonomy, phylogenetics, divergence time estimations and ancestral area reconstructions, nomenclature, and other methods to shed light on the evolutionary processes that shaped the extant biodiversity of the buckthorn family (Rhamnaceae Juss.). In a first step, this thesis provides a major contribution to the taxonomic assessment and arrangement within the buckthorns. By describing the new genus Pseudoziziphus Hauenschild, and resurrecting four genera, this thesis highlights and compensates underestimated diversity. Simultaneously, it provides a phylogenetic framework based on the largest molecular data set in the family so far. In a second step, the taxonomic and
phylogenetic framework was used to reconstruct solid divergence time estimates and ancestral area estimates for Rhamnaceae, with a focus on the ziziphoid lineage, and the genus complex Alphitonia Reissek ex Endl. sensu lato. By this, it was possible to unravel evolutionary processes within the history of Rhamnaceae and provide a biogeographic scenario for the ziziphoid lineages, including Alphitonia s.l.:General Introduction 1 Bibliography 19 Chapter 1 36 Phylogenetic relationships within the cosmopolitan buckthorn family (Rhamnaceae) support the resurrection of Sarcomphalus and the description of Pseudoziziphus gen. nov. 37 Bibliography 48 Appendix 1 50 Supplements 55 Chapter 2 56 Analysis of the cosmopolitan buckthorn genera Frangula and Rhamnus s.l. supports the description of a new genus, Ventia 57 Bibliography 67 Appendix 1 68 Supplements 71 Erratum 72 Chapter 3 74 The influence of the Gondwanan break-up on the biogeographic history of the ziziphoids (Rhamnaceae) 75 Bibliography 96 Appendix 1 105 Appendix 2 115 Supplements 117 Chapter 4 118 Biogeographic analyses support an Australian origin for the IndomalesianAustralasian wet forest-adapted tropical tree and shrub genus Alphitonia and its close allies (Rhamnaceae) 119 Bibliography 144 Appendix 1 153 Appendix 2 161 Appendix 3 166 General Conclusions 172 Bibliography 182 Appendix 186 Spatio-temporal evolution of Allium L. in the Qinghai-Tibet-Plateau region: Immigration and in situ radiation 187 Curriculum Vitae 200 Declaration of Independent work 207 Author contributions 208
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Etude chimique et caractérisation de principes colorants historiquement employés dans l’impression des indiennes en Provence / Chemical study and characterisation of dyes historically employed in the manufacture of "indiennes" in ProvenceCuoco, Guillaume 27 November 2009 (has links)
Ces travaux portent principalement sur l’étude de trois plantes tinctoriales : la garance, le nerprun et la gaude. Ces végétaux ont fait l’objet de nombreuses cultures en Provence et constituaient la principale matière première en colorants rouges et jaunes pour les teinturiers et les artistes. Une optimisation des conditions d’extraction des colorants de la garance assistée par ultrasons a été effectuée en utilisant un modèle statistique. Ce procédé d’extraction simple, rapide et efficace, a été comparé à deux autres techniques utilisées conventionnellement. Une étude cytohistologique des racines de garance a permis d’examiner les effets apportés par les différents procédés d’extraction. Les cellules traduisent après extraction par ultrasons, de profondes déstructurations fournissant une explication au plus important rendement en colorant extraits en comparaison aux extractions classiques. Une étude fondamentale sur l’identification des colorants extraits à partir des fruits immatures d’espèces appartenant au genre Rhamnus a été effectuée. Une approche chromatographique utilisant la CLHP/UVVisible/ SM a permis d’identifier la partie flavonol. Elle présente principalement des composés glycosylés dont la partie rhamninoside est liée sur le flavonol en position 3 ou 4'. Des flavonols 3-O-acétyl-rhamninoside ont également été caractérisés et sont spécifiques de Rh. saxatilis. Les fruits matures renferment aussi des anthraquinones qui ont été séparées des flavonols et concentrées en utilisant l’Extraction sur Phase Solide (SPE). Après analyse par RMN, des dérivés rhamnoside et arabinoside acétylés de l’émodine, jamais décrits dans la littérature, ont été identifiés dont le 6-O-(3',4' diacétyl)-arabinopyranoside d’émodine et 6-O-(2',3',4'-triacétyl)- arabinopyranoside d’émodine présents seulement dans Rh. alaternus. Les colorants jaunes de la gaude (Reseda luteola) ont été analysés par électrophorèse capillaire. En comparaison avec la CLHP, un gain important de la durée d’analyse a été observé tout en conservant une séparation convenable. L’ensemble de ces résultats expérimentaux a pu être appliqué avec succès à l’étude de colorants extraits à partir d’objets et d’échantillons historiques provenant de collections muséales et comprenant notamment des indiennes du XIXème siècle. Enfin, des essais de teintures ont été réalisés, en collaboration avec la société Les Olivades dans le but de développer une gamme de tissus à base de colorants naturels / This work concerns the study of three tinctorial plants: madder, buckthorn and weld. These plant species produced many cultures in Provence and represented the principal raw material in red and yellow dyes for dyers and artists. An optimisation of extraction conditions for madder dyes, using ultrasounds, was carried out with a statistical model. This easy, fast and effective extraction process was compared with two other conventional techniques. A cytohistological study on madder roots permits to examine effects produced by the different extraction processes. Cells reveal, after ultrasonic extraction, profound structural alterations, explaining the high yield in extracted dyes in comparison with classical methods. A fundamental study on the dyes identification extracted from Rhamnus species green fruits was carried out. A chromatographic approach using HPLC-UV-MS permits to identify the flavonol fraction. It is mainly composed of glycosiled compounds where the rhamninosid part is linked in position 3 or 4’ on the flavonol nucleus. 3-O-acetyl-rhamninosid derivatives were also characterised and they are specific to Rh. saxatilis species. Ripe fruits contained anthraquinonic compounds that were separated from flavonols and concentrated using Solid Phase Extraction (SPE). After NMR analyse, acetyl rhamnosid and arabinosid derivatives of émodine, never described in the specialised literature, were identified as emodin-6-O-(3',4'-diacetyl)-arabinopyranosid and emodin-6-O-(2',3',4' triacetyl)-arabinopyranosid were only present in Rh. alaternus. Yellow dyes of weld (Reseda luteola) were analysed by capillary electrophoresis. In comparison with HPLC, a reduced run time was observed while preserving a suitable separation. These experimental results were successfully applied to the study of ancient samples belonging from museums and including “indiennes” of the XIXth century. Finally, dying tests were carried out, in collaboration with Les Olivades society, in the aim to develop textiles containing natural dyes
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Connecting the dots: Remote sensing of Glossy and Common Buckthorn (Frangula alnus and Rhamnus cathartica) in the Oak Openings Region of Northwest OhioZmijewski, Kirk A. 22 August 2013 (has links)
No description available.
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Avaliação dos aspectos toxicológicos dos fitoterápicos: um estudo comparativo / Evaluation of toxicological aspects of the herbal medicines:a comparative studyTurolla, Monica Silva dos Reis 13 April 2004 (has links)
Esta Dissertação apresenta informações gerais sobre os medicamentos fitoterápicos e os aspectos toxicológicos de uma amostra de dez plantas medicinais comercializadas como medicamentos fitoterápicos no Brasil, pesquisados junto aos principais bancos de dados e fontes públicas de informação. A análise dos medicamentos fitoterápicos cobre as dimensões histórica, econômica e farmacêutica. No tocante aos aspectos toxicológicos, foram avaliados os dados de toxicidade pré-clínica de dez plantas selecionadas, e realizado um levantamento das informações publicadas para Hypericum perforatum e Piper methysticum, relacionadas ao termo toxicidade, segundo três importantes bancos de dados. Adicionalmente, este trabalho aborda as propostas para realização de ensaios de toxicidade pré-clínica para os fitoterápicos segundo a OMS e legislação brasileira, e as normas para avaliação de substâncias químicas segundo a OECD. / This thesis presents general information on herbal medicines and on the toxicological aspects of a sample of ten medicinal plants traded as herbal medicines in Brazil. The survey was carried out in the main databases and public sources of information. The analysis on the herbal medicines encompasses the historical, economic and pharmaceutical dimensions. In what concerns toxicological aspects, data on pre-clinical toxicity were evaluated for Hypericum perforatum and Piper methysticum, these keywords being related to toxicity in three important databases. In addition, this study discusses the proposals for pre-clinical toxicity trials on herbal medicines according to WHO and the Brazilian legislation, and the standards for evaluation of chemical substances according to OECD.
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Avaliação dos aspectos toxicológicos dos fitoterápicos: um estudo comparativo / Evaluation of toxicological aspects of the herbal medicines:a comparative studyMonica Silva dos Reis Turolla 13 April 2004 (has links)
Esta Dissertação apresenta informações gerais sobre os medicamentos fitoterápicos e os aspectos toxicológicos de uma amostra de dez plantas medicinais comercializadas como medicamentos fitoterápicos no Brasil, pesquisados junto aos principais bancos de dados e fontes públicas de informação. A análise dos medicamentos fitoterápicos cobre as dimensões histórica, econômica e farmacêutica. No tocante aos aspectos toxicológicos, foram avaliados os dados de toxicidade pré-clínica de dez plantas selecionadas, e realizado um levantamento das informações publicadas para Hypericum perforatum e Piper methysticum, relacionadas ao termo toxicidade, segundo três importantes bancos de dados. Adicionalmente, este trabalho aborda as propostas para realização de ensaios de toxicidade pré-clínica para os fitoterápicos segundo a OMS e legislação brasileira, e as normas para avaliação de substâncias químicas segundo a OECD. / This thesis presents general information on herbal medicines and on the toxicological aspects of a sample of ten medicinal plants traded as herbal medicines in Brazil. The survey was carried out in the main databases and public sources of information. The analysis on the herbal medicines encompasses the historical, economic and pharmaceutical dimensions. In what concerns toxicological aspects, data on pre-clinical toxicity were evaluated for Hypericum perforatum and Piper methysticum, these keywords being related to toxicity in three important databases. In addition, this study discusses the proposals for pre-clinical toxicity trials on herbal medicines according to WHO and the Brazilian legislation, and the standards for evaluation of chemical substances according to OECD.
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Adaptation and Constraint in the Plant Reproductive PhaseBolmgren, Kjell January 2004 (has links)
<p>Conservatism is a central theme of organismic evolution. Related species share characteristics due to their common ancestry. Some concern have been raised among evolutionary biologists, whether such conservatism is an expression of natural selection or of a constrained ability to adapt.</p><p>This thesis explores adaptations and constraints within the plant reproductive phase, particularly in relation to the evolution of fleshy fruit types (berries, drupes, etc.) and the seasonal timing of flowering and fruiting. The different studies were arranged along a hierarchy of scale, with general data sets sampled among seed plants at the global scale, through more specific analyses of character evolution within the genus <i>Rhamnus </i>s.l. L. (Rhamnaceae), to descriptive and experimental field studies in a local population of <i>Frangula alnus</i> (Rhamnaceae). Apart from the field study, this thesis is mainly based on comparative methods explicitly incorporating phylogenetic relationships. The comparative study of <i>Rhamnus</i> s.l. species included the reconstruction of phylogenetic hypotheses based on DNA sequences.</p><p>Among geographically overlapping sister clades, biotic pollination was not correlated with higher species richness when compared to wind pollinated plants. Among woody plants, clades characterized by fleshy fruit types were more species rich than their dry-fruited sister clades, suggesting that the fleshy fruit is a key innovation in woody habitats. Moreover, evolution of fleshy fruits was correlated with a change to more closed (darker) habitats.</p><p>An independent contrast study within <i>Rhamnus</i> s.l. documented allometric relations between plant and fruit size. As a phylogenetic constraint, allometric effects must be considered weak or non-existent, though, as they did not prevail among different subclades within <i>Rhamnus</i> s.l. Fruit size was correlated with seed size and seed number in <i>F. alnus</i>. This thesis suggests that frugivore selection on fleshy fruit may be important by constraining the upper limits of fruit size, when a plant lineage is colonizing (darker) habitats where larger seed size is adaptive.</p><p>Phenological correlations with fruit set, dispersal, and seed size in <i>F. alnus</i>, suggested that the evolution of reproductive phenology is constrained by trade-offs and partial interdependences between flowering, fruiting, dispersal, and recruitment phases. Phylogenetic constraints on the evolution of phenology were indicated by a lack of correlation between flowering time and seasonal length within <i>Rhamnus cathartica</i> and <i>F. alnus</i>, respectively. On the other hand, flowering time was correlated with seasonal length among <i>Rhamnus</i> s.l. species. Phenological differences between biotically and wind pollinated angiosperms also suggested adaptive change in reproductive phenology.</p> / <p>Äpplet faller inte långt från trädet. Men varför? Den biologiska mångfalden präglas i stor utsträckning av fylogenetiskt bevarade karaktärsdrag; närbesläktade arter är lika. Det pågår en diskussion bland evolutionsbiologer om i vilken utsträckning denna konservatism är ett resultat av naturlig selektion eller av en begränsad anpassningsförmåga.</p><p>Denna avhandling diskuterar begreppet evolutionära begränsningar i relation till den reproduktiva fasen hos växter. I fokus ligger särskilt evolutionen av bärliknande (endozoochora) frukter respektive evolutionen av säsongsmässiga mönster (fenologi) för blomning och fruktsättning. Avhandlingen är hierarkiskt organiserad så att olika delstudier gjordes på olika skalnivåer: fenologi- och fruktevolution analyserades för fröväxter respektive gömfröiga växter; inom brakvedssläktena Rhamnus och Frangula (Rhamnaceae); samt för en lokal population av brakved (Frangula alnus). Populationsstudien baserades på såväl experimentella som deskriptiva data, medan övriga studier i huvudsak genomfördes med fylogenetisk komparativ metodik baserade på litteraturdata. Som en del av de komparativa studierna rekonstruerades fylogenetiska hypoteser för Rhamnus s.l. utifrån DNA-sekvenser (ITS, trnL-F), vilka gav stöd för att Frangula och Rhamnus är monofyletiska systersläkten.</p><p>I en biogeografiskt kontrollerad fylogenetisk kontrastanalys upptäcktes inga skillnader i artrikedom mellan djur- och vindpollinerade växter. Bärliknande frukter verkar dock vara en betydelsefull karaktär (key innovation) i skogsmiljöer. För det första var fylogenetiska klader med bärliknande frukter mer artrika än systerklader med torra frukter. Dessutom var uppkomster av bärliknande frukt korrelerad till habitat med mer sluten vegetation.</p><p>En fylogenetisk kontrastanalys av allometriska effekter visade på en positiv korrelation mellan växtindividens och fruktens storlek inom Rhamnus s.l. Upprepade analyser av dessa allometriska samband i olika monofyletiska subklader inom Rhamnus s.l. indikerar dock att allometri, såsom evolutionär begränsning, är svag. I populationsstudien av F. alnus var fruktstorlek positivt korrelerad till såväl fröantal som frövikt. En generell hypotes utifrån denna avhandling blir därför att frugivorer (de djur som äter bären och därmed sprider växtens frön) utövar ett starkt selektionstryck på växter som koloniserar ett habitat där fröstorlek är adaptivt, eftersom fruktstorlek påverkar frugivorernas (ssk. fåglars) sätt att hantera frukten.</p><p>Reproduktiv fenologi var korrelerad till fruktsättning, fröspridning och fröstorlek hos F. alnus. Detta stödjer tanken att evolutionen av blomnings- och fruktsättningstider begränsas av avvägningar (trade-offs) och partiella beroenden mellan blomning-, fruktsättnings-, spridnings och rekryteringsfaserna. Inomartsvariation i blomningstid för F. alnus respektive getapel (Rhamnus cathartica) över en nordeuropeisk latitudinell transekt var inte korrelerad till säsongslängd, vilket antyder att utvecklingen av blomningstider är evolutionärt begränsad. Å andra sidan påvisades en sådan korrelation mellan blomningstid och säsongslängd i en mellanartsstudie inom Rhamnus s.l. Den fylogenetiska kontrastanalysen mellan djur- och vindpollinerade växter visade också på adaptiva skillnader i fenologi. Blomningstiderna inom en klad med biotiskt pollinerade arter var mer åtskilda än inom den vindpollinerade systerkladen, och den välkända iakttagelsen att vindpollinerade träd blommor tidigare på säsongen fick även stöd i ett fylogenetiskt komparativt perspektiv.</p>
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