2 resultados para Hierarchy of classes
em Academic Archive On-line (Stockholm University
Resumo:
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. 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 Rhamnus s.l. L. (Rhamnaceae), to descriptive and experimental field studies in a local population of Frangula alnus (Rhamnaceae). Apart from the field study, this thesis is mainly based on comparative methods explicitly incorporating phylogenetic relationships. The comparative study of Rhamnus s.l. species included the reconstruction of phylogenetic hypotheses based on DNA sequences. 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. An independent contrast study within Rhamnus 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 Rhamnus s.l. Fruit size was correlated with seed size and seed number in F. alnus. 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. Phenological correlations with fruit set, dispersal, and seed size in F. alnus, 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 Rhamnus cathartica and F. alnus, respectively. On the other hand, flowering time was correlated with seasonal length among Rhamnus s.l. species. Phenological differences between biotically and wind pollinated angiosperms also suggested adaptive change in reproductive phenology.
Resumo:
Maria McCann paints a dark picture of masculinity and its effects in her novel As Meat Loves Salt (2001). The violent Jacob Cullen struggles with his masculinity as he faces the intricacies of religion, sexuality and politics in the midst of the English Civil War where he falls in love with fellow soldier Christopher Ferris. By using R.W. Connell and James Messerschmidt’s framework for the hierarchy of masculinities, I explore masculinities on local, regional and global levels and emphasized femininity in a close reading of McCann’s novel. My aim is not only to analyse the masculinities of the novel but also to use the framework to redefine toxic masculinity in order to make it a useable concept when analysing masculinities in literature. I redefine toxic masculinity because it lacks a clear definition anchored in an established framework used to study masculinity that does not see masculinity as inherently toxic. I believe that anchoring it to Connell and Messerschmidt’s framework will make it a useable concept. Due to the novel’s relationship to the Bible, I will use masculinity studies done on David and Jesus from the Bible to compare and reveal similarities with the masculinities in the novel, how they appear on the local, regional and global levels in the novel and its effects. I draw parallels between the love story in As Meat Loves Salt to the love story of David and Jonathan in the Bible by using queer readings of David and Jonathan in order to explore how masculinity affects the relationships and how the novel uses these two love stories as a study of toxic masculinity and how it relates it to hegemonic masculinity.