A HISTORY OF THE STUDY OF PHYLLOTAXIS

The study of the patterns formed by similar units in plants (e.g. leav es, scales, florets) is traced from the first primitive observations i n ancient times to the sophisticated studies of today. Mathematics ent ered into the study early, at first as a way of describing the pattern s observed, with Fibonacci numbers and the golden section playing a ma jor role, and later in the construction of models designed to explain their origin. Observation and experiment alternated with theory. Expla nations offered alternated between functional and causal. Functional e xplanations that were at first teleological gave way to those based on the idea of natural selection. Causal explanations alternated between the chemical and the mechanical. New light has been cast on the subje ct with the realization that phenomena similar to phyllotaxis occur in realms outside of botany. (C) 1997 Annals of Botany Company.