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1	Comparative demography and life history evolution of plants Mbeau ache, Cyril January 2014 (has links) Explaining the origin and maintenance of biodiversity is a central goal in ecology and evolutionary biology. Some of the most important, theoretical explanations for this diversity centre on the evolution of life histories. Comparative studies on life history evolution, have received significant attention in the zoological literature, but have lagged in plants. Recent developments, however, have emphasised the value of comparative analysis of data for many species to test existing theories of life history evolution, as well as to provide the basis for developing additional or alternative theories. The primary goal of this study was to explore existing theories of life history evolution using a dataset of demographic information in the form of matrix population models for a large number of plant species. By projecting average matrix population models for 207 plant species, life tables and fecundity schedules were obtained and, in turn, were used to estimate relevant life history parameters. These parameters were then used to explore the i) lability of life history traits in plants ii) their continuum of life history variation, iii) the evolution of senescence and iv) the significance of demographic entropy in population ecology. Elasticities and sensitivities of life history traits showed significant phylogenetic signal compared to other life history traits, although, all the values of phylogenetic signal observed were < 1 indicating that life history traits are generally labile. Eighty one percent of species in the datset had mortality curves that increased with age compared to one hundred percent of species that showed a reproductive value curve that decreases with age at the end of life. In particular, the parameters that measured pace and duration were inversely related suggesting in general, the presence of senescence in our data set. Finally, the tenets of the directionality theory based on demographic entropy were generally not confirmed. This study provides an important contribution to the life history evolution of iteroparous perennial plants and confirms existing theories on life history evolution. 581.3
2	Social evolution in class-structured populations Rodrigues, Antonio M. M. January 2014 (has links) Inclusive fitness theory concerns the study of social traits. Often, individuals differ in their phenotype (e.g. size, weight, nutritional state) independently of their genetic make up, that is, individuals differ in their quality. Individuals can then be classified into different “classes” according to their quality, which enable us to understand social evolution in class-structured populations. This is important because individuals in natural populations often differ in quality, either because of intrinsic factors (e.g. size), or extrinsic factors (e.g. resource availability). My thesis concerns the evolution of social traits in class-structured populations. In chapter 1, I make a brief introduction to my thesis, providing the abstract of each chapter. In chapter 2, I outline a general theory of individual quality, where I show how individual quality impacts social evolution in two fundamental ways. In chapter 3, I show that resource heterogeneity greatly influences the evolution of conditional social behaviour. In chapter 4, I show that temporal group-size heterogeneity promotes the evolution of both conditional helping and harming. In chapter 5, I analyse the effect of individual quality on kin selection. I find that individual quality has an important impact in kin selection, which can lead to extreme forms of social behaviour. In chapter 6, I show that stable environments promote the evolution of negative density-dependent dispersal, while unstable environments promote the evolution of positive density-dependent dispersal. In chapter 7, I show that budding and low local quality promote the evolution of dispersal and cooperation. 577
3	Évolution dans des populations structurées en classes Soares, Cíntia Dalila 05 1900 (has links) No description available. Populations structurées par âge. Théorème du taux de croissance. Paramètre Malthusien. Valeur reproductive. Populations structurées en classes. Modèles démographiques. Croissance démographique. Sélection dépendante des fréquences. Séparation par échelle de temps. Équation de réplication. Théorie de Perron-Frobenius. Théorie des jeux évolutionnaires. Matrice de Leslie. Probabilité de fixation. Deux échelles de temps. Coefficient d'ascendance. Processus généalogique. Jeu de bien commun. Age-structured populations. Growth-rate theorem. Malthusian parameter. Reproductive value. Class-structured populations. Demographic models. Population growth. Frequency-dependent selection. Timescale separation. Replicator equation. Perron-Frobenius theory. Evolutionary game theory. Age-class-structured population Leslie matrix. Diffusion approximation. Fixation probability. Two timescales. Population-structure coefficient. Fixation fitness coefficient. Ancestry coefficient. Genealogical process. Public goods game.

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