On of the less well known 'rules' of composition is Fibonacci's Spiral - I was amused this afternoon to find the rotted remains of a tree stump that illustrated this... albeit slightly imperfectly - but only slightly!
Wow, that really does look like Fibronacci's Spiral. You had commented on my August 21 posting of a sculpture depicting that spiral. I'm thinking of putting together a composite of that image turned in all four directions. Stay tuned....