The Wisdom Of Trees (Da Vinci Knew It) : NPR
Hurricanes topple plenty of trees, but when you think about it, the more amazing thing is that many trees can stand up to these 100-mile-per-hour winds.
Now a French scientist has come up with an explanation for the resilience of trees. And astonishingly, the answer was first described by Leonardo da Vinci 500 years ago.
Leonardo noticed that when trees branch, smaller branches have a precise, mathematical relationship to the branch from which they sprang. Many people have verified Leonardo’s rule, as it’s known, but no one had a good explanation for it.
French physicist Christophe Eloy wasn’t particularly interested in trees, but he does specialize in understanding how air flows around objects — objects like airplane wings and such. So he decided to see whether he could solve the mystery of the branching trees.
“I just did it because it was a nice problem, but I think there are some implications for real-life applications,” Eloy says.
Leonardo’s rule is fairly simple, but stating it mathematically is a bit, well, complicated. Eloy did his best:
“When a mother branch branches in two daughter branches, the diameters are such that the surface areas of the two daughter branches, when they sum up, is equal to the area of the mother branch.”
Translation: The surface areas of the two daughter branches add up to the surface area of the mother branch