Seashell & Nautilus

Why are sea shells, nautilus, and snails so pleasing to the human eye? That’s right, the golden spiral is also found in these creatures. As shown in the picture to the below, it is quite obvious to see the shell in the golden spiral. Without knowing it was related to mathematics, one would first assume that the spiral was modeled after seashell. Or was the seashell modeled after the spiral? Either way, it is obvious that these two figures are very similar in shape and proportion. If you were to draw the a golden rectangle on the seashell then draw the squares resulting in the picture below, you can see how these are related.