I hope you don't mind me answering your post ( it was not directed at me).
DNA tries to keep the life that it is ( say a human) in the center. What I mean by that, it tries to give a human all the parts and traits that humans have. There is great variety in humans tall to short, dark skin light skin etc. Mutations are usually considered bad. Like having 2 heads or four arms, or growths that are not supposed to be there.
The point is that though, DNA allows for variety, but it keeps you a human. You do not become something else. There is no chimp to human, jump. That is what we see today, and why should today, be any different from earlier times? The fossil record supports this and so does DNA.