If you think selective breeding is proof of evolution, then you need to go back to the drawing board.
Dogs are still dogs, different ? yes, but most early attempts left them either dead or the inability to reproduce.
And BTW, these experiments were conducted, not in nature but by human intervention.
If you think great variability built into the DNA is proof of an evolutionist, then I’ll share my drawing board with you. Yes. Dogs are still dogs.
But, Marmeduke is not Scooby-doo.