Monday, March 25, 2013

What Darwin Didn't Know- Ch 1 - The Scope of Challenges Pt 4 - Whole-Package Problem

Book Cover: What Darwin Didn't Know
I've dove into Geoffrey Simmons' "What Darwin Didn't Know" (2004), to evaluate an anti-evolution book.

I'm maintaining an index of my responses here.

Today's Chapter - 1: The Scope of Challenges - Part 4: The Problem of the Whole-Package Phenomenon- Pt 1

"The Whole-Package Phenomenon?"

Oh, right, irreducible complexity! I was wondering when this would be officially trotted out. It's about the closest that creationists/intelligent design proponents get some any kind of cogent objection to the theory of evolution.

The Dover Trial

It's interesting to note that this book was published about one year before the infamous Dover vs Kitzmiller trial, where many of the items Simmons brings up in the book, were laid out before the court to defend the school board's anti-evolution decisions. This was the Creationist/ID's best opportunity to put their best arguments forth - and they were steamrolled.

If you have about two hours, there's a lecture by Ken Miller, who participated in the trial, about the topics brought up during the trial, particularly irreducible complexity.

At this point, Irreducible Complexity is basically in ruins. I don't think I'll spent a lot of time personally tearing apart each example, but I'll do some research to find good resources as to what's wrong with them.

Irreducible Complexity (IC)

In short, the concept of Irreducible Complexity is the notion that, given any structure (like the bacterial flagellum , where if any individual part is removed, the function breaks, so therefore evolution could not have selected for the structure, because how can one naturally select for something that isn't functional yet? They claim evolutionary theory cannot account for these structures.

Irreducible complexity (IC) is an argument by proponents of intelligent design that certain biological systems are too complex to have evolved from simpler, or "less complete" predecessors, through natural selection acting upon a series of advantageous naturally occurring, chance mutations.
The main problem I see IC proponents making is that they're operating under a very limited understanding of evolution. The argument stems from assuming that all that evolution does is successive additive steps. 

Photo of Natural Stone Arch
Courtesy  Mlcreech on Wikipedia
... but there are different types of paths than that one type.

Consider the stone arch (pictured to the right).

I'm willing to bet you can quickly discern how that object formed, even without an intelligent architect. This structure would be irreducibly complex (mostly - obviously if a single small chunk is removed it would probably stand - but you'll get the point) - if any cross section is removed at any point along the arch, the structure would collapse.

According to the IC proponents, the fact it's irreducibly complex would necessarily mean that it couldn't occur naturally.

... but you know how it formed - a mound of dirt/rock piled up as sediment, and was then eroded away, with one mound having its middle section eroded away, most likely from wind.

So, to abstract it to a two-stage process:

  • A non-IC structure was established by additive steps.
  • The non-IC structure had parts subtracted until it was irreducibly complex

If you can understand this, you'll understand how many of these arguments tend to fail. A person who isn't aware of these nuances of evolutionary theory might be swept up by the concept of IC erroneously. If you understand how this structure can form on its own, then you currently have a superior understanding of how evolution works than Michael Behe and Geoffrey Simmons - with many IC proponents frequently couching the argument explicitly in the idea that evolution works strictly through additive steps, and only additive steps, completely ignoring the subtracting steps, transfers of function, etc - enough pathway types to account for virtually all their IC examples.

As I mentioned, there's another event that occasionally happens, that solves many of these examples of irreducible complexity, is a concept known as "transfer of function" (or "Exaptation") - where a non-IC structure forms, but then is used for another function entirely, with maybe a few extra parts, that then becomes an IC structure.

The common examples is that of a bacterial syringe that it might use to attach to, or inject into, another cell, that's a non-IC structure, but could, with a few modifications, become a functional motor that's then an IC structure (this is covered in depth in the Dover Trial - starts at 39:45 in the Ken Miller video above).

The proponents of Irreducible Complexity rely on this over-simplification of evolution to fabricate the "problem" - sure, there are structures that stop working if a part is removed, but there are combinations of other paths, outside of a simple additive series of steps, that can get to the same spot, even if it is the more scenic route.

IC is a wall. You can't walk through the wall directly forward. What do you do? You step to the side until you find a door, step forward through the door, then side-step back, and congratulations, you've gotten to the other side of the wall, that was just in front of you before, without breaking any laws of physics (or the wall)!

IC is basically a failure of imagination, and when used to support the concept of Intelligent Design (ID), becomes an argument from ignorance - since "evolution cannot explain it and we don't know what else it can be, the answer must be an intelligent designer."

Next up, I'll start going through the examples Simmons brings up in the book.

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