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Monday, March 3, 2014

Pineapples!

You don't have to travel to Hawaii to enjoy the sweet, decadent taste of a fresh, well.... ripe, pineapple. And what's even better is that you can experience a little bit of Fibonacci, while you enjoy a 'taste of the islands.'


Count the spirals coming out of the base of this pineapple (kind of tricky). There are exactly eight!
Photo credit: Tom Robinson

While I am not overly enamored with my picture taking skills, I did want to show you what I'm talking about. And these patterns you see here are found on just about any pineapple, whether you cut it off the stalk in Oahu or pick it up at the local grocery store. Look at the very bottom of the pineapple. This was where it was connected to the plant and was removed when harvested. In the image above, you can just make out the spiraling scales, drawn in black marker, but frustratingly hard to make out. If you count your way around the base of the pineapple, you will count exactly eight spirals. Eight is a Fibonacci number!

Truth be told, some pineapples' scales are harder to count than others, and they don't always make a nice, clean pattern. But check it out the next time you are at the store (or in Hawaii!). I bet you find the same number of spirals that I did.

Notice how these highlighted (in black marker) scales make a spiral path up the fruit in the opposite direction from the last group? Counting each of the scales from bottom to top, I found.... yep - 13 scales.
Photo credit: Tom Robinson
Now, back up from the pineapple a little bit and look at the scales spiraling the OTHER direction. You can see them in the image above circled in black marker. Counting from the bottom to the top, curving around the fruit in a spiral, I counted exactly thirteen scales - another Fibonacci number! You have to do this carefully. It turns out that not all pineapples have scales that grow in exactly a clean spiral. But keep looking - I am certain you will find what you are looking for.

I have included some better drawings and images below so you can see these patterns a little more clearly. Mahalo!
Notice the 'phyllotaxy' in this image. Yum! Actually,
you can see some of the
spirals a little more clearly here.
Photo credit: geochembio.com

Next time you find yourself with a pineapple at hand, use this handy guide to start counting the scales in the spirals. There are at least two distinct patterns indicated here.
Photo credit: thinkquest.org

2 comments:

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  2. I have included some better drawings and images below so you can see these patterns a little more clearly. Mahalo!
    Pineapples Guide

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