I'm a young earth creationist, so of course I don't believe we have any "common ancestor" because the entire concept is unbiblical nonsense. But if you're interested check out this article that goes over how scientists may pretend that they have everything wrapped up in a neat little package with a bow on top but in reality they have many competing theories and no end in sight on how to solve their dilemma.

The Human-Ape Missing Link -- Still Missing | Evolution News