Chapter 8: Implications for Everyday Systems

Section 6: Growth of Plants and Animals

Observed phyllotaxis

Many spiral patterns in actual plants converge to within a degree or less of 137.5°, though just as in the model in the main text, there are usually deviations for the first few elements produced. The angles are particularly accurate in, for example, flower heads—where it is likely the positions of elements are adjusted by mechanical forces after they are originally generated. Other examples of phyllotaxis-like patterns in biology include the scales of pangolins and surfaces of tooth-like structures in certain kinds of rays and sharks.

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