A scientific theory is a proven hypothesis backed by facts, laws, and observations. I.E. Gravitational theory, Cell Theory, Atomic Theory, Theory of evolution, Theory of relativity etc. If you are confused about chimps and humans than you do not understand evolution. We have observed direct creation of a new species in fruitflies. Also ring species. DNA alone prooves using chromosome 2 in the human genome that we did share a common ancestor with apes and bonobos. You can choose to believe this or not, but it [i]is[/i] a fact.