By “Biff” Andrews

Pi, which is rounded to 3.14159, is a constant number that deals with circles. Pi-r-squared is the area of a circle. Pi times D is the circumference. Everybody learns that by the ninth grade.

But there’s another constant number, Phi, which also appears everywhere in nature. Ninety-nine percent of the populace is unaware of it. The number is 1.618033….

The number is based on the Fibonacci sequence — 0-1-1-2-3-5-8-13-21-34-59-93 … — where each number is the sum of the two numbers before it. Simple enough, right?

But this “Phi” — the Divine Proportion, the Golden Mean, the Golden Ratio — appears everywhere in nature, primarily in three ways — spirals, pentagrams, and phyllotaxis, the arrangement of leaves around a stem.

Just as an example, the length of the human forearm is 1.618 times the length of the hand. In the hand, the three bones of each finger are in Golden Ratio lengthwise, and we have 8 fingers total, 5 digits per hand, 3 bones in each finger, 2 bones in one thumb and one thumb on each hand. Is it a coincidence that these are all Fibonacci numbers?

The cochlea of the inner ear is a perfect Fibonacci spiral. Coincidence? The features of the human face are all in Golden Proportion.

Let’s examine spirals in nature. Look at the top of a whelk, or a moon eye or a Scotch Bonnet, or the side of a chambered Nautilus. Any of them forms a perfect Golden Spiral.

Place a 1-inch square next to another, next to a 2-inch square, next to a 3, next to a 5, next to an 8 and arrange them in a circle and you have a perfect spiral. By the way, this is the arrangement of the interior rooms of the Parthenon.

Phi in art, music, mathematics, and so on are each books unto themselves.

Look at the arrangement of seed nubs on a tapered pinecone or squares on a pineapple. They are arranged in spiral form. The seeds on a sunflower are in a spiral/counterspiral arrangement.

Coincidence?

How about the petals on flowers? There are three on a lily and iris, five on a buttercup, larkspur and columbine, eight on delphiniums, 13 on corn marigold ragwort and cineraria, 21 on aster and black-eyed Susan, 34 on plantain and pyrethrum, 55 or 89 on michaelmas daisies and the astraceae….

Coincidence? Or “spooky”?

Or is it evidence of Divine Proportion, an orderly universe set in motion by a rational Supreme Being?

Deism was a 17^th– and 18^th-century belief created in the Enlightenment that the world was the creation of a “Watchmaker God” who was indifferent to humans. But if you could understand science, you could understand God.

I don’t think so. Understanding nature — and that there are certain “constants” that help one understand it — this may be the beginning of wisdom.

But don’t take my word for it. Google “Phi” or the “Golden Mean” or the “Golden Ratio” or the “Golden Section” or “Divine Proportion.”

I was 60 years old before I ever heard of phi and read a couple of books on it. I am convinced it’s not a coincidence.

Susan and Bradford “Biff” Andrews are retired teachers and master naturalists who have been outdoor people all their lives, exploring and enjoying the woods, swamps, rivers and beaches throughout the region for many years. Email them at b.andrews22@live.com.