Introduction

Abstract

All living organisms are, at various stages in their life history, capable of growth. Given suitable conditions, this can mean change in size (Fig. 1.1), change in form and/or change in number. These three processes together form an important part of the phenomenon of life. Among natural systems they help to distinguish the living from the non-living though, in a sense, many non-living systems also grow. Crystals, river deltas and volcanic cones can change recognizably within human time-scales.