quote:
Originally posted by SixOfSpades:
If a system can be enclosed, and then manipulated, and the results of that manipulation are predicted according to a theory, and it turns out that that prediction was correct, is it not logical to infer (after hundreds of tests) that the THEORY was correct?
In other words, if a population of fruit flies (some with normal wings, some with curled wings) is placed in a sealed case with food hanging from the ceiling, the theory of natural selection states that the flies with normal wings would thrive, and those with curled wings would eventually die out, even though both types are free to inter-mate and produce offspring, because those with curled wings have more difficulty in reaching the food. Actually performing this experiment shows this prediction to be valid, and therefore, the theory of Natural Selection is vindicated.
Natural Selection and Evolution are essentially one and the same: The difference is scale. Natural selection operates on the scale of the individual organism; Evolution operates on the scale of the entire species. And since we now know that changes in the environment provoke changes in organisms, and that our own environment is constantly changing, the logical conclusion is that we have been evolving ever since we existed.
Indeed, we have been evolving as long as we've existed. No arguments from me there. There is more difference than scale when common ancestry and random beginnings of life come into play. These entail more than natural selection. As you said, evolution operates on the scale of an entire species, and I personally belief it operates at an even higher order than that. However, I do not believe that it operates, for example between mammals and reptiles, reptiles becoming mammals and so forth, and there just isn't proof at this point to say that this happens.