Prodi writes:
The problem is that evolution makes predictions in both directions and anywhere in between. Any number of vestigials (or complete lack of vestigials) can be explained as being due to the randomness of mutation and uncertainties about what selective pressures were at work. As result, nothing is really proved since the evidence would be accommodated regardless of what is actually found.
Not at all. Evolutionary theory predicts that features, vestiges or innovations occurred via small steps based on prior structures and did not just appear suddenly out of no where. If only humans had appendixes or Ostriches had wings with no evolutionary history that would be a problem.
ID would not predict vestigial structures in any form at all.
Prodi writes:
If we found a frog with vestigial wings, people would see it as an organ “on its way in” rather than “on its way out,” and possibly even use it as further evidence for evolution. For example, flying fish have wings, but that isn’t considered to be evidence against evolution, in spite of the fact that they clearly have no ancestors with better wings.
If fully formed bird style wings were found on flying fish (and no less on a frog) that would present a *serious* problem to evolutionary theory. No amount of hand waving and mumbling about mutations and selective pressure would dismiss the problem. I don't know much about flying fish (frying fish is another story
) but without looking it up I would take a long-odds bet that they are adapted fins and NOT structured like tetrapod limbs.
This is the key difference between evolution adapted features and what one would expect or predict by a Intelligent Designer.
Think in terms of innovations to the automobile. Automobile feature progression are an outcome of Intelligent Designing. So that when lets say fuel injection became perfected this feature was quickly added to all makes - Fords, Chevys, Toyotas, and even motorbikes, outboard motors, etc.
If automobile progression was an evolutionary process you would expect this feature to popup suddenly in say Chevys and be found only in Chevys and not Fords or Toyotas. However if fuel injection was really an advantageous feature you would expect that this features would eventually be "discovered" in Fords but probably implemented in an entirely new and different way being subjected to specific historical constraints of Fords.
And this is what we see in the special adaptation of flying creatures! The various mechanisms that allow a creature to fly are widely different and occurred at different evolutionary time frames along different evolutionary paths resulting in different ways to do the same thing.
[Note: my acknowledgment to Jar for first highlighting this metaphor]
One finally thought. I don't know in what terms of an Intelligent Designer you are thinking of but what do think about the character of this designer in view of the parasitic nature of life? Here is thread I would like to capture you thoughts on this issue.
Message 1
This is the poison pill to most theistic varieties of Intelligent Design.