Why animals don't have wheels

Cecil's Columns/Staff Reports
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Consider this…If higher order animals had wheels, the only advantage would be when gravity is working with you (i.e. downhill). It would seem like it isn’t very energy conservative. When you walk uphill, or even level for that matter…your energy expended by taking a step and placing it on a surface, moving your leg and placing it on a surface maybe 2 or 3 feet in front of you. A wheel has constant contact with the surface it is on. Since contact equals friction, friction equals resistance, and resistance requires a greater energy expenditure to complete a task, it would seem that a wheel would be more of a hindrance then a benefit. Besides, wheels wear down…when was the last time someone had to have the soles on their feet replaced?

This is in fact a comment on Cecil’s column: Why has no animal species ever evolved wheels?, so I have moved the topic to the appropriate forum. – CKDextHavn

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CJD1984’s comments are very good except that the soles on your feet are being constantly replaced by new skin cells as the old cells wear off.
I know of only one animal wheel motion for transportation in nature, and that is a small one-celled animal with a wheel motion on its single cila that rotates to move it forward.
Other single cell animals tend to have cila that whip back and forth for forward motion.

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Welcome to the SDMB, and thank you for posting your comment.

The column (including Slug Signorino’s illustration) can also be found on pages 209-211 of Cecil Adams’ book “Triumph of the Straight Dope”.