Thirteen year old Aidan Dwyer was walking in the woods in Upstate New York in the winter and noticed a spiral pattern to tree branches. Aidan realized the tree branches and leaves had a mathematical spiral pattern that could be shown as a fraction. After some research he also realized the mathematical fractions were the same numbers as the Fibonacci sequence. “On the oak tree, the Fibonacci fraction is 2/5, which means that the spiral takes five branches to spiral two times around the trunk to complete one pattern. Other trees with the Fibonacci leaf arrangement are the elm tree (1/2); the beech (1/3); the willow (3/8) and the almond tree (5/13).”*



Aidan’s backyard in Northport, NY.

The 7th grader next wondered why nature used such a pattern? He concluded trees do so to collect maximum sunlight. So, he constructed two side by side solar arrays – one a typical flat-panel array that was mounted at 45 degrees, and the second, a solar array based on the Fibonacci pattern of an oak tree. He put both outside facing south. To his amazement, during the month of December, the tree design made 50% more electricity, and the collection time of sunlight was up to 50% longer than the flat panel array!

Aidan discovered that the Fibonacci pattern helps deciduous trees, in higher latitudes, efficiently track the Sun and collect the most sunlight even in the thickest forest, on the cloudiest days. If an object blocks the light to a flat panel array, the array stops producing energy. But, the Fibonacci pattern allows some solar ‘leaves’ to collect sunlight, while some ‘leaves’ are in shade. Plus, the Fibonacci pattern helps the branches and leaves on a tree to avoid shading each other. Snow and debris slide off as well. Aidan is currently building tree arrays based on the other Fibonacci patterns of the elm, beech, willow and almond trees. He questions; is one pattern more efficient than another?



The American Museum of Natural History has awarded Aidan a Young Naturalist Award for 2011.

See the detailed description of his discoveries on the Museum’s website: *www.amnh.org

Postscript: Many have questioned why Aidan did not measure power output from the solar cells, instead he only measured voltage, without a load attached (“open circuit”). The American Museum of Natural History stands by its award.