The metaphor of dance is a very apt way to portray the unfolding and increasing complexity of plant-life on Earth. The dance of plants is the dance of plant form in space and time. From a reductionist point of view, the conversion of solar energy is what plants are really all about, either at the level of the individual, or the community, or even in the characteristics of the plant-life of a given region. Form, is the physical expression of the energy captured and transformed by plants, and it provides the basis for all ecological relationships. It is not surprising then that, broadly speaking, the plants of tropical regions that have access to the greatest input of radiant energy also have the greatest exuberance, while those of energy- and nutrient-limited environments, such as alpine moorlands and bogs, have a more restricted range of body plans.