A Numbered Daisy

An alternate version of a color plate for “Dancing elves and a flower's view of Euclid's Algorithm,” published in 2006 in the Mathematical Intelligencer, volume 28, no. 4. The photograph is a closeup of the center of a daisy, and the seeds are numbered in the order of growth. The coloring highlights families of 21, 13, 8, and 34 spirals. All of these numbers are in the Fibonacci sequence
1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...,
in which each number is the sum of the previous two numbers.

The original daisy photograph was taken by Marian Goldstine. I learned how to number seedheads properly from John H. Conway.