Neither the constitutive nor the inducible evolved strains grew on lactose in the absence of IPTG. (Hall 1982b)
I might not be getting the idea here, but doesn't this say that neither of the strains were capable of growing on lactose in the absence of IPTG? That is to say, both the original and the evolved strains lacked this capability?
This would indicate to me that we can ignore the significance of this third mutation when examining the point that this example provides. The bacteria developed the ability to metabolize lactose, a seemingly irreducibly complex system. They did not develop the ability to transfer the lactose through their cell membrane, a different matter altogether. The argument is not that cells can arbitrarily develop any quality that is required to live in an environment on demand; for instance neither strain would survive without a petri dish, but it makes no sense to consider this lack a mark for irreducible complexity.
In any case, the question is not if this particular bacterial strain could spontaneously develop the ability to metabolize lactose after devastating genetic damage. The point is that genetic alteration in a specific area does not make the system come tumbling down. The irreducible complexity argument suggests that knocking out one part of the system would prohibit everything from functioning properly, and thus there is no way to develop into such a system gradually. Not only is this argument inherently flawed (it may have been supported by other mechanisms which were selected out as they no longer contributed to survival) but arbitrarily including other lacking factors makes the comparison pointless. It is like arguing that a car is irreducibly complex because if you remove the pistons it cannot climb walls; it never could climb walls, so be frikkin' impressed when it develops pistons out of the blue and leave it at that.
Essentially, it seems to me that an irreducibly complex system (that was already in place) was tinkered with and mutated into a similar irreducibly complex system.
A system which was thought to be irreducibly complex had an element removed, and it did not cease functioning but rather mutated into a working arrangement. Thus, it was proven not to be irreducibly complex.
Consider the order 1,2,3,4,5 that's an arrangement. If 3 goes down then you can reconstruct it.
Umm... we can reconstruct it because we know what should go in the order. It does not reconstruct itself, or mutate a new number that can go there. Finally, it isn't even a system since it does not do anything. It is equally effective with or without the number, or even with a mutated new number.
Honestly I don't even know what, if anything, you were trying to get at there. Perhaps you could try again?
But why tinker with a system that already knows how to deal with the situation Traderdrew, that's how it was designed.
Wow, the entire thread appears to have whooshed right over your head. Let me summarize here: Some people believe (for a variety of stupid reasons) that organisms were designed, and to try to find proof of this they suggest that organisms are irreducibly complex. A system that it irreducibly complex is suggested to be a system where removing one part of it will cause the entire system to stop working; the significance being that this would prevent it from having developed gradually over time.
This was shown not to be the case for bacteria who had a chunk taken out of their metabolic system, and yet managed to acquire a new piece to go there that the previous strain did not. Thus, the metabolic pathway was not irreducibly complex as it previously appeared.
Furthermore, the entire concept is rubbish because evolution can produce systems which fail if a portion is removed. This makes irreducible complexity a failed argument for creation anyway.
It doesn't really matter if the system which was broken was IC or not but it happens that it was. That is why the removal of part broke it. I think you are wrong that the system did not cease functioning. It was IC and it broke.
It ceased functioning in the way it used to function, but it did end up functioning in a different manner. One portion of the metabolic pathway was removed and yet the rest of the pathway was perfectly functional with the addition of an alternate piece.
Does irreducible complexity demand the removal of one portion without the addition of a substitute? Either way, the argument is dead.
We have complete storage systems that know what has to be there. Not because it has it's own intelligence but, because that's they way they were programmed. When you turn on your computer, how does it know what to do?
When you turn on your computer it reads magnetic polarities off of a platter in your computer's hard drive. This storage system does not know what has to be there, rather it retrieves what we put there. Those polarities can and do become corrupted and that will cause the computer to function incorrectly.
Perhaps you don't know enough about computers to draw such analogies Lucy-poosy.