"So what?" - Antiguv
So...technically, an organism would be genetically superior if it had all of its functionality without also having unused genetic code as baggage. Natural Selection *should* favor those without the unused code...
So what? If the organism has no problem reproducing and nothing pressuring it to extinction, it will abide. Just because something would be preferable doesn't mean evolution will force it into existence so long as what is already the case is sufficient for the task at hand. Evolution doesn't have a structural objective independent of a functional one..
However, might I add that you just gave an excellent argument for why an intelligent designer would be expected to design differently..
The Intelligent Designer was the low bidder.
Unless evolution was the design objective, in which case it's pretty amazing stuff.
"Completely unused code requires more energy for genetic copying, yet delivers, by definition, no benefit to the organism."
Actually, Guv, Southack is right, only very marginally, on this. I can think of some environments where blowing ATP on conserving DNA that is not used would put a real squeeze on an organism (thermophilic organisms growing at the expense of coal gas combustion emmissions, for example). However, this would not be true of Giardia - it's got plenty of plenty when it's inside you. And that goes for the vast majority of organisms. The minor "waste" of energy (since that what it all boils down to) would probably not put any organism out of existence in competition with other organisms in its niche. It would take something more substantial.
"So what?" - Antiguv
So...technically, an organism would be genetically superior if it had all of its functionality without also having unused genetic code as baggage. Natural Selection *should* favor those without the unused code...