Pick up a pinecone and count the spiral rows of scales. You may find eight spirals winding up to the left and 13 spirals winding up to the right, or 13 left and 21 right spirals, or other pairs of numbers. The striking fact is that these pairs of numbers are adjacent numbers in the famous Fibonacci series
Stuart Kauffman (1996). “At Home in the Universe: The Search for the Laws of Self-Organization and Complexity”, p.151, Oxford University Press