Fibonacci Rectangles and Shell Spirals

Another illustration that exemplifies the Fibonacci numeric sequence starts with one small square of 1 inch on each side (see Figure 2.1). After drawing the first box, a second box of 1 inch in size is added in the progression of the Fibonacci sequence (0, 1, 1, 2, 3, 5).

Figure 2.1.

On top of both of these, continue to draw 1-inch boxes, thereby completing a square the size of 2 (1+1=2). Again, repeat this process in the sequential order of the Fibonacci series, as a new square can be drawn that touches both a unit square and the latest square of side 2. This results in having sides 3 units long and another touching both the 2-square and the 3-square that now has sides of 5 units (see Figure 2.2).