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1	Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails 2014 October 1900 (has links) According to theory, habitat selection by organisms should reflect the associated probability of survival or reproductive success. Understanding habitat selection, at multiple scales, is of interest not only from a theoretical perspective, but from an applied perspective for species conservation. Northern pintails (Anas acuta) are migratory, temperate-nesting birds that breed in greatest concentrations in the prairies of North America. Declining populations suggest that habitat loss and changing land use may have decoupled formerly reliable fitness cues from selection of suitable nest habitat. I used data from 62 waterfowl nesting study sites in prairie Canada (1997–2009), to examine whether nest survival, a primary fitness metric, at nest and habitat patch scales, was predictive of habitat selection at corresponding scales. In addition, I used systematic long-term annual pintail population monitoring data (1961–2009), and recruitment indices (juvenile:adult female ratio) from hunter harvest, to examine adaptive habitat selection among landscapes within the Prairie Pothole Region (PPR). The influences of breeding population density and landscape composition were examined at all scales. At nest and patch scales, pintail nest survival varied with nest initiation date, nest habitat, pair density, and landscape composition. Nest habitat preference reflected patterns in nest survival suggesting nest habitat preference is adaptive. Preference was generally low for habitats with low nest survival (e.g., spring-seeded cropland) and high for habitats with high nest survival (e.g., idle grassland). Differences in preference among habitats weakened at high breeding density and in landscapes with more grassland. Population-level recruitment tended to be greater when pintails settled in landscapes that were wetter than normal, contained more grassland, and were moderately variable in local elevation. Pintails were strongly associated with wetter than normal landscapes but shifted into cropland-dominated landscapes and flatter landscapes when populations were high. My results indicated that pintails express adaptive habitat associations with density-dependence acting through buffer mechanisms. Finally, I use the results of the above analyses to, 1) model and map the estimated long-term average spatial abundance of pintail pairs across the PPR as a function of landscape-level covariates, and 2) construct a deterministic model predicting pintail productivity given habitat and landscape attributes. These models allow conservation efforts to be targeted to affect the most birds, and they allow estimation of the demographic response to conservation actions. northern pintail habitat selection demographic models conservation planning
2	Forecasting Mortality Rates using the Weighted Hyndman-Ullah Method Ramos, Anthony Kojo January 2021 (has links) The performance of three methods of mortality modelling and forecasting are compared. These include the basic Lee–Carter and two functional demographic models; the basic Hyndman–Ullah and the weighted Hyndman–Ullah. Using age-specific data from the Human Mortality Database of two developed countries, France and the UK (England&Wales), these methods are compared; through within-sample forecasting for the years 1999-2018. The weighted Hyndman–Ullah method is adjudged superior among the three methods through a comparison of mean forecast errors and qualitative inspection per the dataset of the selected countries. The weighted HU method is then used to conduct a 32–year ahead forecast to the year 2050. Mortality modelling mortality forecasting Lee–Carter method singular value decomposition functional demographic models functional principal components analysis mean forecast errors ARIMA. Other Mathematics Annan matematik
3	Peter Guthrie Tait : new insights into aspects of his life and work : and associated topics in the history of mathematics Lewis, Elizabeth Faith January 2015 (has links) In this thesis I present new insights into aspects of Peter Guthrie Tait's life and work, derived principally from largely-unexplored primary source material: Tait's scrapbook, the Tait–Maxwell school-book and Tait's pocket notebook. By way of associated historical insights, I also come to discuss the innovative and far-reaching mathematics of the elusive Frenchman, C.-V. Mourey. P. G. Tait (1831–1901) F.R.S.E., Professor of Mathematics at the Queen's College, Belfast (1854–1860) and of Natural Philosophy at the University of Edinburgh (1860–1901), was one of the leading physicists and mathematicians in Europe in the nineteenth century. His expertise encompassed the breadth of physical science and mathematics. However, since the nineteenth century he has been unfortunately overlooked—overshadowed, perhaps, by the brilliance of his personal friends, James Clerk Maxwell (1831–1879), Sir William Rowan Hamilton (1805–1865) and William Thomson (1824–1907), later Lord Kelvin. Here I present the results of extensive research into the Tait family history. I explore the spiritual aspect of Tait's life in connection with The Unseen Universe (1875) which Tait co-authored with Balfour Stewart (1828–1887). I also reveal Tait's surprising involvement in statistics and give an account of his introduction to complex numbers, as a schoolboy at the Edinburgh Academy. A highlight of the thesis is a re-evaluation of C.-V. Mourey's 1828 work, La Vraie Théorie des quantités négatives et des quantités prétendues imaginaires, which I consider from the perspective of algebraic reform. The thesis also contains: (i) a transcription of an unpublished paper by Hamilton on the fundamental theorem of algebra which was inspired by Mourey and (ii) new biographical information on Mourey. 510.92
4	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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