Cancer and Evolution?

Strolling back from my morning coffee run, I noticed a pigeon with a giant cancerous growth underneath its left wing. I didn’t know pigeons suffer from tumors, although it surely makes sense.

I was feeling pity for the poor little fella, but suddenly my thoughts turned in a different direction: what if the tumor growth had actually been something that helps the pigeon survive? What if the distinguishing features of a pigeon were actually determined not by slow mutation and selection, but by a mechanism that allows for sudden appearance of a new feature without slow motion?

I was always puzzled at cancer, because it seems to occur naturally in animals, as if it were a normal condition of life. Given how much time the body spends putting itself in balance, it would have seemed that the cell regulation would have had an easy time suppressing whatever causing the uncontrolled growth that goes with cancer.

Now, if tumors in general are the way new features are tested, this would explain a lot. Animals that are not able to have tumors because they optimized their cellular reproduction would be doomed to eternal stagnation. Animals that are incapable of controlling their reproduction fully would have an easier chance at sudden mutation.

Just a thought, but a fruitful one at that.