I have 2 cats, who enjoy sleeping on the bed with my wife and me, but during the night we notice that they both start at the foot of the bed, and creep up, leapfrogging each other to be higher up and closer to our heads. This occasionally erupts into fights, over what I can only assume is their position on the bed.
My question is, is this normal behavior? Is one cat trying to assert dominance over the other one by their position on the bed?
Background on the cats: Male(neutered) 1.5 years old, female(spayed) 6-7 months old. Get along seemingly okay except for some altercations (see this question).