Among structural systems inspired in nature, tree structures – or branching structures – are perhaps the ones which most directly present a formal and functional analogy. But the structural behavior of trees and the requirements they have to meet differentiate them from branching structures.
In the first place, the nature/structure relation of these systems is clear if we compare the function of the parts of a tree, which explain its form and generating processes, with that which gives rise to branching structures. In trees, leaves serve an essential function for growth and require exposure to the sun, for photosynthesis. Branches are supports that allow efficient distribution of the leaves, depending on the kind of tree and on the environment, ensuring maximum solar exposure throughout the day. Similarly, the branches – together with the roots and trunk, which also have the function of giving support and shape to the tree – form a system of conduits for water, nutrients, and the sugar generated in the leaves. Hence, functional requirements are what more clearly explain the shape and configuration of the various elements of a tree (...)