Butterflies and Moths

I received a comment from a friend on the butterflies. Natural selection through breeding can be considered survival of the fittest, which would be evolution. This is a great point. What I was concerned about was applying such a broad label with so many unknowns. Did the butterflies lose some characteristics by breeding with such a small gene pool? Thus did they de-evolve? Do these butterflies periodically go through this process? In which case it would not be evolving or de-evolving, but a normal part of their long-term life cycle. Thinking about butterflies; Dallas was emendated with web worms this year. Some trees were stripped nearly bare of leafs. Breeding conditions were ideal with the abnormally cool and wet weather we have had the last few months. A few days ago they all disappeared. Yesterday two white moths found each others on the inside of my back door. Looking on the web Species Hyphantria cunea - Fall Webworm Moth these webworm pictures of the moth match what was in my house. If all of the webworms turn into white moths at the same time we should have a spectacular show.