Irreducible Complexity

“…Natural selection can only choose systems that are already working…
if a biological system cannot be produced gradually it would
have to arise as an integrated unit, in one fell swoop,
for natural selection to have anything to act on.” 1
Michael J. Behe

Irreducibly complex mechanisms, living or man-made, require a system of co-dependent components in order to function.

Today’s world turns on personal computers. Take away the hard drive and the irreducibly complex machine becomes useless junk. Without a keyboard or the electronic mouse, the machine would simply stand-by, waiting for instructions—but unable to function.

computer mouse in mouse trap

© Stephen Coburn

Like man-made computers, animal and plant life forms could not exist without all DNA components in place. Biochemist Michael J. Behe coined landmark phraseology when he suggested molecular systems in living organisms are irreducibly complex.” He illustrates the world of molecular machines by citing the mousetrap as a prime example. A mousetrap is close to the simplest human designed mechanism imaginable. When all its components function in unison, the trap destroys mice. Remove any single part, and the trap morphs into harmless fragments of useless matter.

The simple but “irreducibly complex” mousetrap consists of five basic parts anchored by four staples. It requires the complete, designed package of parts for minimal function. A spring too weak, a trigger too short, or a missing staple and the mouse might steal the cheese, survive unscathed and scoot away safely with the last laugh.

One skeptic suggests the trap could do without the wooden base by stapling the trap’s metal parts to the floor. The argument fails, for the floor itself becomes an essential part of the mechanism.

A fully functioning mousetrap is the product of human intelligence. No one argues that inanimate machines design and build themselves without input from an intelligent source.

Design and construction of living molecular mechanisms requires input from an intelligent source. Living mechanisms display designs infinitely more complex than objects designed by human intelligence. Assembling operational living systems requires insight beyond nature’s whims.

Canyons separating everyday life forms have their counterparts in the canyons that separate biological systems on a microscopic scale. Like a fractal pattern in mathematics…unbridgeable chasms occur even at the tiniest level of life.” 2

Whether whales transitioning from bears, or birds from dinosaurs, part-way-there transitional forms couldn’t survive a gradualist genetic journey.

A prime example of irreducible complexity in the living world is the bacterial flagellum, a molecular machine which functions with 40 basic components, 30 of which are unique.

The flagellum’s microscopic propeller cranks at an amazing 100,000 RPM (Rotations per Minute) and is capable of abruptly stopping and reversing on a quarter turn. If any single component is missing, the entire organism breaks down. Time is of the essence. It’s an all-or-nothing scenario; each component must be in place simultaneously for the living mechanism to function. 3

“Irreducible complexity” is the joker in evolution’s card deck. Organs of living systems cannot evade this cardinal principal. Human eyes could not see without optic nerves and could not survive without the built-in luxury of being bathed by the lachrymal gland’s soothing liquid.

Behe cites the chemical apparatus marshaled by the half-inch bombardier beetle as an irreducibly complex system in action. When threatened by an enemy it can release a scalding hot liquid as a defense.

The components of the system are (1) hydrogen peroxide and hydroquinone, which are produced by the secretory lobes; (2) the enzyme catalysts, which are made by the ectodermal glands; (3) the collecting vesicle; (4) the sphincter muscle; (5) the explosion chamber; and (6) the outlet duct.” 4

Behe inquires rhetorically: “What exactly are the stages of beetle evolution, in all their complex glory? Second, given these stages, how does Darwinism get us from one to the next?” 4

As the number of required parts increases, the difficulty of gradually putting the system together skyrockets, and the likelihood of indirect scenarios plummets. “Darwin looks more and more forlorn.” 5

This is an excerpt from a chapter of the 2016 Edition
of “Three Days Before the Sun”, now available
from leading online retailers.


Copyright © 2012 Warren L. Johns.  All Rights Reserved.  Contact: