Chapter 8: Implications for Everyday Systems

Section 6: Growth of Plants and Animals

Branching in animals

Capillaries, bronchioles and kidney ducts in higher animals typically seem to form trees in which each tip as it extends repeatedly splits into two branches. (In human lungs, for example, there are about 20 levels of branching.) The same kind of structure is seen in the digestive systems of lower animals—as visible externally, for example, in the arms of a basket star.

From Stephen Wolfram: A New Kind of Science [citation]