Proceedings of the National Academy of Sciences of the United States of America, Vol. 93, No. 25 (Dec. 10, 1996), pp. 14243-14248 (6 pages) Symmetry is commonly observed in many biological systems.
Symmetry breaking is often seen as a bad thing. The greater the asymmetry in our faces, so we are told, the less attractive we appear to others. However, if nature did not break a subtle symmetry ...