Pine Cone

Segments of a regular polygon are placed along a logarithmic spiral. The positions of the segments are determined by the angular advance of the subsequent segments. The edges of the segments lie along various spirals. When the angular advance is proportional to the golden ratio, the number of spirals are Fibonacci numbers (8, 13, 21 in the default case). Many plants (including pine cones, leaves, and branches) exhibit this arrangement of segments.