Lloyd Demetrius
Lloyd A. Demetrius is an American mathematician and theoretical biologist at the Max Planck Institute for Molecular Genetics at Berlin, Germany, and the Department of Organismic and Evolutionary biology, Harvard University. He is best known for the discovery of the concept, evolutionary entropy, a statistical parameter that characterizes Darwinian fitness in models of evolutionary processes at various levels of biological organization – molecular, organismic and cultural. Evolutionary entropy, an analogue of the Gibbs-Boltzmann entropy in statistical physics, is the cornerstone of directionality theory, an analytical study of evolution by variation and selection. The theory has applications to: a ) the development of aging and the evolution of longevity; b) the origin and progression of age related diseases such as cancer, and neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease; c) the evolution of cooperation and the spread of inequality. Education. Born in Jamaica, he carried out his undergraduate studies in mathematics at the University of Cambridge, UK. He received his PhD in mathematical biology from the University of Chicago in 1967. He was then a postdoc at the University of California, Berkeley. Career. Demetrius was a faculty member in a number of mathematics departments in the  US from 1970–1979: the University of California, Berkeley; Brown University; Rutgers University; and a research scientist at the Max Planck Institute for Biophysical Chemistry, Göttingen (1980–1989). Since 1990, he has been with the Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, first as a visiting professor (1990–1992), and then as an associate in population genetics. He has held visiting professorships at MIT, University of Paris, and was an occupant of a Chaire Municipale, a distinguished visiting professorship at the University of Grenoble. His research includes the application of ergodic theory and the theory of dynamical systems to the study  of evolutionary processes in biological and socio-economic systems. He has also pioneered the application of the methodology of quantum mechanics to the study of allometric relations between metabolic rate and generation time in cells. This work is the mathematical basis for the analysis of cancer and neurodegenerative disorders as metabolic and bioenergetic diseases. Honors and awards. Demetrius was a recipient of a Guggenheim Fellowship in 2019.