Seashell and fibonacci numbers

[Skye]

I found a cone shaped seashell on the beach that had been eroded away so three of the sprirals were cut in half. It looked cool so I took it home, and then I thought of Fibonacci numbers. So I measured the three spirals at their widest points, getting 10 mm, 17 mm and 27 mm.

 

The first two add up to give the last one, and the ratio between the first two is 1.700, between the second two is 1.588. These are pretty close to the golden mean of about 1.618, especially since I was using a dodgy plastic ruler.

 

Ok so it's not ground breaking mathematical work, but it's probably the closest I'll ever get.