If there is no debate
there's no debate among biologists that evolution happens, and that natural selection plus random variation are responsible.
the debate is between the scientists and the creationists. And it only exists because creationists repeat the same mantras over and over again, no matter how many times they are refuted.
Natural selection can only select from existing traits, not create new ones
wow! really!!??
if you'll read closely, crash said
crash writes:
natural selection and random mutation
he did not say "only natural selection".
it is the random mutations that create the new traits.
mutations cannot produce new traits if the potential for variation did not exist
what do you think a mutation is? take the line AAACCCGGGTTT. a mutation might make it AAACCCTTTGGG. You now have two variants.
mutations create variations.
as to your final point (i'm not even going to touch on the past observations, other's are handling that quite well), there is no controversy among biologists, except for the odd one here and there. I garuntee that you will not find a single biologist who rejects the basics of the ToE [(natural selection + random mutation) / time ] for evidentiary reasons. If they do, it will be over religious reasons.