Today I was reading an article where the writer was referring quite comfortably to "insertions, deletions, and mutations" as the source of new or different genes.
That's pretty new stuff ~ 10 years ago they'd have accused you of dipping too much snuff if you included "deletions" or "insertions" with "mutations".
So, stick insects turn their wings on and off ~ through time ~ so much for "...... key rules......".
Turns out that the vast majority of our DNA is not active - like files on a computer whose pointers have dissappeared. Occasional "archaic DNA" gets expressed once in a great as a vestigial tail or a penis bone.
Evolution only favors adaptive traits.. not complexity over simplicity.. otherwise whales wouldn't have evolved away their limbs..