A History of the Study of Phyllotaxis

The study of the patterns formed by similar units in plants (e.g. leaves, scales, florets) is traced from the first primitive observations in ancient times to the sophisticated studies of today. Mathematics entered into the study early, at first as a way of describing the patterns observed, with Fibonacci numbers and the golden section playing a major role, and later in the construction of models designed to explain their origin. Observation and experiment alternated with theory. Explanations offered alternated between functional and causal. Functional explanations 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 subject with the realization that phenomena similar to phyllotaxis occur in realms outside of botany.