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Changes in the rate at which biological evolution proceeds are widespread and common. Advancements in methodology make it possible to characterize such historical evolution more accurately and reveal complex scenarios where rates vary among organismic groups and even between individual lineages. The work presented here embraces such complexity, seeking to exploit phenotypic rate variation to reconstruct patterns and processes of evolution deep in time with unprecedented accuracy. Chapters 1 and 2 demonstrate for the first time that it is possible to reveal historical, directional trends in morphology that played out over millions and millions of years using only data from living species. These trends arose as a consequence of rapid and repeated instances of directional evolutionary change and the approach employed to detect them may be the only way to study historical adaptive trends in morphology that cannot otherwise be observed in the fossil record. Where evolution is fastest, natural selection has acted more strongly; this idea is developed further in Chapter 3 which presents a novel way to characterize an exceptional subclass of rates of morphological evolution that can be defined as positive phenotypic selection. In both Chapters 3 and 4 it is shown that such intense episodes of natural selection have punctuated the evolution of diverse groups including plants, dinosaurs and hominins. Chapter 5 demonstrates that it is possible to uncover explicit underlying causes of positive phenotypic selection and takes us one step closer to being able to truly understand the drivers of natural diversity. As a complete work, this thesis harnesses and exploits phenotypic rate heterogeneity to inform inferences about patterns and processes of evolution deep in time and to understand how natural selection has acted to sculpt morphology, giving rise to the diversity we observe today both in living species and the fossil record.

This thesis explores the relationship between a leading French Catholic family and the Church in the second half of the sixteenth century. This is a socio-cultural study rather than an investigation of the French Church during this period, although some insight into the Church is given. The Church is used to provide a focus for an examination of noble experience. The thesis notes that male and female religious were integral members of the family network. The means by which the dynasty maintained an alternative patrimony in the Church is outlined. Consideration is then given to the resources which high ecclesiastical office brought an individual, both tangible - in the form of economic assets - and more theoretical - access to patronage opportunities and influence, which contributed to an individual's power. The economic resources which benefice tenure brought are examined and their management analysed. Patronage is viewed more as an expression of a noble culture of interacting social networks than as a product of a hierarchical power structure. The position of the Lorraine-Guise Cardinals in relation to the French Church is assessed. Their power within the Church was a result of personal qualities rather than institutional structures. The power which came with tenure is discussed, as is any relationship between ecclesiastical and secular power. A final chapter looks at the experience of women religious. Churchmen and women could contribute in certain ways to family interests, but there is no evidence of large-scale despoliation of the Church through ecclesiastical kin.

All massive nearby galaxies, including our own, host supermassive black holes. Active galactic nuclei (AGN) are seen when such black holes accrete, and when they produce powerful jets of synchrotron-emitting plasma, they are termed radio-loud AGN. The close correlation between black hole mass and galaxy bulge mass in elliptical galaxies indicates that AGN feedback may be the key to the regulation of galaxy formation. It is thus necessary to fully understand the structure of AGN, the way that they are fuelled, and their duty cycle, in order to study the feedback processes and get a clear picture of galaxy formation. In this thesis, independent methods are developed to constrain the accretion disk and radio jet angles to the line of sight. H IX emission from a sub-sample of high-redshift quasars is measured from near-infrared spectroscopy and modelled as sums of different components, including the characteristic double-peaked profile which results from a thin, rotating accretion disk. Comparing the models using Bayesian evidence, almost all quasars were found to have infrared spectra consistent with the presence of a disk. The jet inclination angles of the same set of quasars were constrained by fitting a model, including the effect of Doppler boosting and the receding torus model for dust obscuration, to the radio \ spectral energy distribution. The fitted disk and jet angles correlate strongly, and are consistent with a model in which the radio jets are launched orthogonally to the plane of the accretion disk, as expected if the jet is powered by energy drawn from the spin of the black hole. Both disk and jet angles correlate with the observed linear source size, which is a projection effect; when deprojected using the fitted angles, the distribution of source sizes agrees with a scenario in which the sources expand into the surrounding medium at a constant rate up to ~ 1 Mpc and then shut off, probably as the nuclei become quiescent. The accretion disk angle was found to correlate weakly with the low-frequency radio luminosity, which provides direct, albeit tenuous, evidence for the receding torus model.