I don't understand why an organism reverting to a previous state is in any way a problem. "[i]Since ... every organism's biology is an ever-changing process we [b]must [/b]assume that it won't revert to its original or simpler form anyway[/i]" - but I can't grasp why we should have to assume that at all, nor why the theory would have any problems with organisms doing so? I can not see what that assumption is predicated upon. If there is light, the organism will start adapting to light. If there is then no light, the organism will start adapting to darkness. If the light comes back...and so on. There is no prohibition on life reverting to an original or simpler form - and the joy of the gene means that in that simpler form it will keep a handy little note encoded inside itself on what's a good plan for dealing with light or dark. Packing away all those encyclopedias of information. Evolution has no concept of 'progress', nor of 'good' or of some sense of one thing being better than any other. It is the constant blind search for what works, what prevents the intrinsic pressures of the universe killing it off. It is mindless and without values. Many adherents to the theory posit that whales adapted themselves for the land, but ultimately went right back into the sea. Returning to the sea was a reversion to a prior strategy. Should the universe suddenly loose all environmental pressures - every cell is free from all predation or possibility of damage - then the theory would hold that all life would begin slowly start turning itself back into something like an amoeba, because all the other adaptations are not needed. Through micro-evolution, the complex can become [i]possible [/i]- not inevitable. Evolution is blind - a numbers game, trying combinations until something works works. Me banging on my locker, shouting at it, checking to see if it was really my locker. Given that the history of the planet is finite, whether you care to measure that time-frame in the billions or in the thousands, then complexity was not only not inevitable - it was actually actively unlikely. There was no guarantee I would ever have tried jiggling my locker. The core of Johnson's point remains that the theory "[i]has never been shown to be capable of creating...new complex body parts such as wings, eyes, or brains[/i]." Which on the surface does make complete sense. It's ridiculous to suggest early life detected light and said to itself "Right, I'm going to need eyes, a nervous system, and a cappuccino". But some species did start finding it was very handy to have surface cells that could tell if it was lighter or darker. And then which direction was lighter or darker. And maybe if some part of an area had a darker bit that the rest. Apposition eyes became compound eyes became retina, etc. So on. [I'm clearly making up that example from the top of my head.]