Nautilus Related to Geometry?

Ok nautiluses are not related to geometry, but their shells are a great example of the golden spiral and the Fibonacci spiral. To start off with, what is a Fibonacci spiral? A Fibonacci spiral is made when you take the square root of the area of a square and add that to the square next to it's square root. Expressed mathematically the dimensions would look like 1x1, 1x1 (because there is no square next to it so it is 0+1), 2x2, 3x3, 5x5, 8x8, 13x13, and so on and so fourth. The nautilus's shell does not mirror this exactly, but it is almost the same.

Fibonacci spiral:

The golden spiral is a logarithmic spiral (a self-similar spiral curve) who's growth ratio is the golden ratio (that being a+b is to a as a is to b). Golden spirals (approximate) are also found in galaxies some times. Nautilus shells are not perfect Fibonacci or golden spirals, but they are just about the closest thing in nature to them.