[Shadowfax]

"A fish is a class, not a species. If a salmon evolved into a catfish, that would be speciation."

Thank you. As I said in a previous post, I am reviewing some of the information provided by others before reconsidering my comments on speciation. However, it should be noted that the theory of evolution requires both new, more complex species AND new, more complex classes. The class of animal X must beget a new, more complex class of animal Y without intelligent intervention or the theory of evolution does not work.

I have yet to see any evidence that this has been observed, reproduced, or used to predict anything.

[Coyoteman]

it should be noted that the theory of evolution requires both new, more complex species AND new, more complex classes

Why not less complex?

[MineralMan]

"However, it should be noted that the theory of evolution requires both new, more complex species AND new, more complex classes."

No, it does not require that at all. Again, a misinterpretation of the Theory of Evolution. There is no requirement whatever for increased complexity, just for change and adaptation.

You see, we still have unicellular life on this planet, which negates your statement. In SOME cases lifeforms evolved to be more complex. In others, the level of complexity remained the same, but adaptations evolved to suit new or changed environments.

Increased complexity CAN occur through evolution, but evolution does not REQUIRE it to occur. Only change and adaptation.

Think of all the unicellular life forms on this planet. The number of species in that class outnumber all the rest of the lifeforms. Increased complexity is a rare occurrence in evolution.

[hail to the chief]

I still don't see why a species can't change so much that it is reclassified in another taxa. Species, class, and every other level of taxonomy are divided only by characteristics; it's a scientific application of "If it looks like a duck, and quacks like a duck, it's a duck."