Google searches uncovered that a mathematical concept called the Fibonacci number sequence underlies the structure of tree branches.

WSJ: A Youngster's Bright Idea Is Something New Under the Sun; Scientist Is 13-Year-Old Aidan Dwyer

One of the byelaws prohibits "people climbing on any wall, fence, tree, barrier, railing or structure without a reasonable excuse".

BBC: New laws to combat 'tombstoning' in East Yorkshire