And that's exactly why I have my own set of unique fingerprints. It's because crossing over allows those gametes to obtain genetic information that is unique to that specific sex cell. Now, in our discussion of crossing over, we're going to focus on a type of organism we call the fruit fly. Now, in fruit flies, we're going to study two different traits. We're going to examine the structure of the wings and we're going to discuss the color trait of that fruit fly. Now, in fruit flies, we have two types of wings that can form.