Monday, March 02, 2009

"Are the Mechanisms that Produce Phenotypic Variation "Random"?


Some "intelligent design" supporters have recently asserted that all of the 47+ mechanisms listed in my blog are “random” or “accidental", and therefore the old creationist argument that "RM & NS" doesn't explain the origin and evolution of life is still valid. However, this is simply not the case. On the contrary, a large percentage of these mechanisms are the result of processes that are not “random” by any reasonable definition of that term. I have repeatedly been very careful to point this out, but that clearly has been missed by many "intelligent design" supporters.

It is also not the case that the 47+ processes are not “guided". Indeed they are “guided”, by the various internal and environmental forces that produce both the variations and the various evolutionary mechanisms that operate upon them (i.e. natural selection, sexual selection, founder effects, genetic bottlenecks, neutral “drift” in deep evolutionary time, exaptation, heterochronic development, changes in homeotic development, interspecific competition, species-level selection, serial endosymbiosis, convergence/divergence, hybridization, phylogenetic fusion, background and mass extinction/adaptive radiation, and internal variance).

That said, however, it is also demonstrably the case that none of the mechanisms listed above can be shown empirically to be “foresighted". Indeed, the whole idea of “foresightedness” in natural processes seems to me to violate several very well-established principles of physics, including the Second Law of Thermodynamics.

How can any natural process be empirically shown to be genuinely “foresighted"? Do rocks fall “in order to” reach the ground? Do gas molecules move “in order to” produce the phenomena we describe with Boyle’s Law? Do the electrons in the valence energy shells of hydrogen and oxygen form shared couplets “in order to” produce water? Do particular genetic changes happen “in order to” produce phenotypic changes that have no effects on organisms’ survival and/or reproduction now, but might have in the future? And how can anyone show any of these to be the case?

It is important to note that the terms “foresighted” and “goal-oriented” are not equivalent. The latter term is entirely compatible with both physics in general and evolutionary biology in particular. Indeed, the genomes of all living organisms are “goal-oriented programs” (as most clearly pointed out by Ernst Mayr), in that they organize and control the assembly and operation of the living organisms for which they code.

However, the processes by which such genomes have come into being (i.e. the 47+ mechanisms listed here, operating through the various mechanisms of micro- and macroevolution listed above) have not been empirically shown to be either “foresighted” nor “goal-oriented". It seems to me that this would be extremely difficult, if not impossible to do. What kinds of empirical observations could one conduct that would unambiguously verify today that some component of an existing organism’s genome or phenome was present in that organism now because at some point in the future it might become necessary for that organism’s survival and/or reproduction?

Clearly, once an organism has survived and/or reproduced one can point to its various attributes and say “yes, that attribute appears to have contributed to the organism’s survival/reproduction". However, that is no more evidence of “foresightedness” than a lottery winner saying “I chose these lottery numbers (or bought those particular scratch-off tickets) because I knew they would be winners". This is known as the “fallacy of affirming the consequent” (also called post hoc, ergo propter hoc argumentation) and is logically inadmissible in the natural sciences.

As always, comments, criticisms, and suggestions are warmly welcomed!

--Allen

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4 Comments:

At 3/03/2009 07:21:00 PM, Blogger Steve Petermann said...

"However, the processes by which such genomes have come into being (i.e. the 47+ mechanisms listed here, operating through the various mechanisms of micro- and macroevolution listed above) have not been empirically shown to be either “foresighted” nor “goal-oriented."

So what is the empirical evidence that these processes are NOT "foresighted" nor "goal-oriented? Seems to me this would require a detection scheme for non-intentionality. Is there such a thing or is this just an intuition or "gut-feel"? ID critics often *say* that mutations or other changes are random, but if they mean by that (from a statistics dictionary) "Of or relating to a type of circumstance or event that is described by a probability distribution" that doesn't necessarily mean these changes are not intentional. These types of processes are ubiquitous in all sorts of processes including those we call intentional.

 
At 3/04/2009 12:44:00 PM, Blogger Mike said...

" I have repeatedly been very careful to point this out, but that clearly has been missed by many "intelligent design" supporters."

There comes a point where being diplomatic just slides into apparent sarcasm. Maybe the question is why do they ignore it? My suspicion is that they're locked into the philosophy that there is only one truth, the "God's eye" absolute truth, and that we're capable of knowing what that is. Therefore there is no such thing as separate spheres of knowledge for science and theology. "Intention" MUST be addressed by science because, /sarcasm
after all science is the search for absolute truth, and everyone knows that. /end sarcasm

What is so antithetical to the evangelical "world view" in the idea that "intention" isn't something that can be addressed by this limited, human, construct we call science?

" Seems to me this would require a detection scheme for non-intentionality."

I'm going to be completely undiplomatic and point out that this is stupid. First thing they teach you in research graduate school is that you can't prove a negative. You prove to me that the Flying Spaghetti Monster didn't create the universe, and the number 42, and get back to me.

 
At 3/04/2009 09:38:00 PM, Blogger Steve Petermann said...

I'm going to be completely undiplomatic and point out that this is stupid. First thing they teach you in research graduate school is that you can't prove a negative. You prove to me that the Flying Spaghetti Monster didn't create the universe, and the number 42, and get back to me.


Ok, fine. So non-teleologists should absolutely stop claiming that evolution is non-teleological, right?

 
At 3/04/2009 10:12:00 PM, Blogger Allen MacNeill said...

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