Towards improved predictions of growth and metabolism in the animal kingdom

Metabolism is a fundamental process of life that fuels vital biological processes including growth. The rates of metabolism and growth often correlate with other biological and ecological traits, including body size, in distinct ways. Thus, understanding variation in the body mass-scaling of growth and metabolic rate is an important area of research when studying the ecology, evolution and life histories of organisms. The overall aim of this thesis is to improve predictions of animal growth and metabolic rates, and to explain variation in these processes. Many methods for estimating individual growth rates (rate of mass increase over time) impose invalid assumptions, such as isomorphic (shape-invariant) growth. This thesis proposes a new growth curve fitting framework that relaxes the assumption of isomorphy and can capture marked diversity of growth curves, including exponential and supraexponential body mass change. Furthermore, because growth is fuelled by metabolism, the mass-scaling exponent of growth (