ymelu is incorrect across the board.
To begin with, the Theory of Evolution is certainly falsifiable. (OK, first understand I am not a biologist.) Logically, if you took an organism with a rapid generational period (a fruit fly for example) and placed different populations in separate and measurably different controlled environmental conditions, according to the theory you should note differences between the populations over generational time. Under repeated experiments, if the theory were false, the organisms would never change. (Someone tell me if there is a problem with this logic.)
Not predictable? Hog-wash. Remember that classic study with the moths in England? I can certainly predict the evolutionary change of moth generations based upon a firm understanding of the environmental conditions and a strong understanding of the existing biological function of the organism in question. I can predict the evolution of the species set given a solid foundation. The fact that we often lack that cannot be held against the complex issues of evolutionary change.
From the religious aspect - since it was brought up - I have no problems accepting both the existance of God and the Theory of Evolution. I believe that God, in the understanding of his infinite wisdom and power, is certainly capable of creating and manipulating through a manner as sublime as evolution. To believe otherwise - to my mind - belittles the almighty.
Here I was trying to type up a response in my Crystal Reports class, and find a half-dozen people beat me to my thoughts. :(
e-troon: I accept your observation re: the moths. It is a nice catch, and just the kind of thing I would let slip 15 years removed from any meaningful biology studies. :) Adaptation it is.
However, I would contend that my items regarding the flies still holds. Your question "But will they develop completely new features as a new species?" is valid. The trick would be to maintain the experiment long enough and under conditions sufficient to measure the differences between resulting adaptions and actual species differentiation. Which would be exactly the point to a determined effort to falsify the theory, holding to the origin of this nodeshell.