Natural Patterns

This is another challange based on an old bit of photography course work I did for my A-Level. Photo must be of a pattern found in nature. This can be in the form of something natural forming a natural pattern or a natural pattern on something. The pattern must be the main focus of the photo, but it should not be a simple texture shot. No photos that look like fabric or paint samples will be allowed.Check out sample photso for examples of what I'm after and What I'm not after. For my course work. I bought an octopus from the fish mongers and took close up shots of its tentacles arranged to look intersteing. Also shots of the pattern of it skin at differnt angles with different lighting and DOF.