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Complexity and Evolution

Creationists often say that life must have been created in its current state because it is too complex to have developed through evolutionary processes. There are two flavors of this argument from ignorance, and it is a fallacy that freethinkers and non-freethinkers alike should be aware of.

Both are essentially the same argument and the same fallacy. The argument is known as the “God of the Gaps”; wherever there is a gap in our knowledge; it is simply presumed that god did it.

Flavor 1: Tornados and Airliners

One flavor of the theory is for people with an incorrect understanding of the Theory of Natural Selection. Fred Hoyle inadvertently popularized the Tornado in the Junkyard metaphor in his 1983 book The Intelligent Universe:

“A junkyard contains all the bits and pieces of a Boeing 747, dismembered and in disarray. A whirlwind happens to blow through the yard. What is the chance that after its passage a fully assembled 747, ready to fly, will be found standing there? So small as to be negligible, even if a tornado were to blow through enough junkyards to fill the whole Universe.” (p.19)

This meme promptly took off among proponents of creationism, launching many books and sermons. Variants of this metaphor were invented, each involving order arising from chaos by random chance. Creationism was rebranded as “Intelligent Design.”

Unfortunately, this metaphor or straw-man argument completely misrepresents the Theory of Natural Selection as saying that something random happened and then- poof! – complex order appeared!

Actually, the opposite is true. Natural Selection proposes that survival and reproduction do not occur randomly. Instead, survival and reproduction occur consistently more frequently among organisms with traits that are adaptive to their environments than among organisms with traits that are maladaptive.

Organisms with traits that promote survival and reproduction in their environments out-reproduce organisms without those traits, and therefore each successive generation has more instances of that trait.

Does that sound like a roll of the dice, with an equal probability of any outcome?

The majority of Americans are not taught about Natural Selection in schools, so this wrong, random-chance definition of the theory may be the only one they’ve ever heard.

Flavor 2: The God of the Gaps

In contrast to the folks who simply don’t understand natural selection, professional religious apologists actually tap into scientific literature in areas such as archeology and molecular biology.

They look for observations that have not yet been explained. A gap in our understanding, they propose, must be where god did things.

If they find a case where we’ve found a fossil for an ancient organism that is very similar to another species, but has key differences, they will point to the fact we do not yet posses a transitional fossil as evidence that god created the two species separately.

The subsequent discovery of the transitional fossils doesn’t result in abandonment of creationism, but rather results in moving on to the next fossil gap Sometimes it is claimed that two new gaps exist between the transitional fossil and the other two!

More sophisticated versions of the god of the gaps argument propose that organic structures with many interdependent parts such as the eye or a cell’s flagellum could not have evolved because only one of those parts could appear in an organism at any given time. This concept is called “irreducible complexity.”

Because any one part is useless without the rest of the assembly, it confers no evolutionary advantage. Therefore the entire apparatus must have appeared all at once, personally designed by a god.

Assuming the unlikelihood of spontaneous assembly, it is proposed that god makes the little flagella that bacteria use to swim around in our colons. (Unfortunately, we’re not making this stuff up, folks.)

As you can see, we’ve circled back to the airliner in the junkyard argument: It’s too complex to have appeared all at once.

The answer is: It didn’t. The Theory of Natural Selection requires change to occur in gradual, advantageous increments.

Irreducible Complexity Debunked

Regardless of the flavor of the god of the gaps argument, it has been debunked. First of all, it is largely based on a false characterization of the Theory of Natural Selection.

The tornado operates by random chance with only one step, whereas evolution operates according to a systematic process applied upon an uncountable number of organisms at any given moment and across eons of time.

Also, examples of transitional fossils are not at all rare. Indeed, all fossils are transitional – the concept of species is simply a human invention to categorize them.

Any interested person with either a textbook or access to the internet can see that the tree of life has essentially been mapped, using decades of evidence consistent with evolutionary theory. If you’re going to talk fossils, there’s no excuse for ignorance on this point.

Also, evolutionary pathways have been identified for many of the examples of supposed “irreducible complexity” cited by creationists.

For example, the bacterial flagellum we mentioned earlier – a spinning, whip-like motor and propeller built at the molecular level – has been shown to resemble an earlier and simpler structure built for secreting toxins into cells. Huge advances have also occurred in our understanding of the evolution of the eye.

The dominos keep falling for the god of the gaps argument as scientific knowledge expands. Curiously, though, creationist literature still features the debunked arguments.

Is this a failure of intellectual honesty? You decide.