May 18, 2007 Ballistics and the Math of Dandelions

I am watching the birds come to the feeders. I realize birds rely on trajectory. They understand the force of gravity and use it to their advantage. Now that the leaves are out, birds tend to work through holes. There is a hole I can see from the dining room, I cannot see from the library. From the dining room I can see a path through the leaves that goes back 300 meters ever increasing in height to near the tops of the trees. From the library holes only extend back about 50 meters.

I watched a Rose-breasted Grosbeak bomb in from 250 meters out. All the way through the hole. There were twists and turns to be sure. The path was not that of a falling body, The Grosbeak checked its’ fall and turned with the lift of its’ wings. A chickadee will do this, but not with the twists and turns. It follows an almost straight path. Dewit, dewit. A series of convex curves but straight on the y axis. I wonder if coming from the neotropics differentiates the Grosbeak form the Chickadee? If spending the majority of one’s life in a world with leaves as opposed to a world where leaves fall to the ground makes a difference?

Since we are on the topic of mathematics I wonder how many people have really looked at a dandelion seed head? It is a perfect ellipsoid. The number of strands in a single seed pod seems to always be a prime 61, 73, 89... I wonder if anyone has taken the time to count the individual seeds or plot their relationship? To me they seem to be arranged on the basis of a pentagon which would lead me to hypothesize it may be related to phi, 1.618. Like pi and e, phi is one of those numbers that seem to be fundemental to the structure of the universe.