"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