Some horses run fast, way out in front while others trot along more slowly at the back.
Until earlier in this century, scientific research was much the same. There was a lot less interaction, One person might be inventing the bicycle, while someone else in another part of the world was working on the steam engine. To give an example of this lack of communication, Oxygen had to be discovered 3 times before people finally accepted that it really did exist. Nowadays, research is still like a team of horses, but they're all yolked together, all interdependent upon each other, so that one can't race ahead without the co-operation of the others. A better understanding of the visual system will help us significantly in our understanding of the hearing system.