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The Mystery of the Genome
Figure 13.
Irreducible complexity. In our red wagon example, the simplest improvement one might imagine would be some misspellings that would convert our red wagon into a blue tricycle. This seemingly small evolutionary step forward could never happen by chance because it requires creation of many new components, each of which represents “irreducible complexity”. It is not hard to imagine a misspelling that would change the paint code, or cause a wheel to fall off. However, to make an operational tricycle that actually works (something selectable by our quality control agent), requires extensive re-working of most of the components. Just one new component – the pedal apparatus – illustrates this. Creation of an operational petal apparatus for our little red wagon could not arise from a few misspellings. Several entirely new chapters in the manual would be required for manufacturing and assembling the various components of the pedal apparatus. But the new pedal apparatus would still not work – without a place for one to sit, and a place for one’s legs! Very obviously, the corruption of a wagon’s assembly manual via random misspellings (even with the help of our quality control agent) could never result in a shiny new blue tricycle. It could only lead to a run-down and broken wagon.