Phyllotactic pattern generation: A conceptual model

Abstract

A conceptual model is proposed here that shows how all types of whorled and peculiar patterns in phyllotaxis derive straightforwardly from normal and anomalous spiral patterns. This is a complete model of phyllotaxis, integrating the author's interpretative model for generating spiral patterns. The paper underlines that a better understanding of the variety of phyllotactic patterns, and of the transitions between them, involves a phylogenetic perspective. It stresses the working hypothesis that spiral patterns are primitive and that all other patterns, such as whorled systems, are by-products of evolution from spirality. An important epistemological consequence on mathematical modelling is drawn out of this hypothesis, namely that models of knowledge or interpretative models, able to take care of the spiral patterns, must be formulated and then followed by simulation, mechanistic or conceptual models that are able to reproduce the transitions to all other types of patterns. © 1988 Annals of Botany Company.