Cellular Automaton - Mathematical / Biological Process

Pictured - Conus (3-5) and Cymbiola (1-2) Shells. A computer generated form using a Mathematical Model (6).

Patterns of some seashells, like the ones in Conus and Cymbiola genus, are generated by natural cellular automata. The pigment cells reside in a narrow band along the shell’s lip. Each cell secretes pigments according to the activating and inhibiting activity of its neighbour pigment cells, obeying a natural version of a mathematical rule.

Have a look at this gif showing a computer generated simulation from jeremykun.com: http://jeremykun.files.wordpress.com/2011/06/randomlife.gif?w=1800