@bluedoodlee,
A lot of hardwoods bruise and there really isn't anything you can do to prevent it other than throwing down some rugs in areas where there is a lot of foot traffic or replacing it with a harder wood.
It's not enough to know that the floor is "pine" or "cherry" -- you have to know what kind of pine or cherry it is as the hardness can be very different. For example, American cherry has a Janka rating of 950, Brazilian cherry has a rating of 2350.