 Some research has shown that cats rarely pick fights, but when they do it is usually for protecting food and/or litters, and defending territory.The first sign of an imminent tomcat duel is when both cats draw themselves up high on their legs, all hair along the middle of their backs is standing straight up, and they mew and howl loudly as they approach one another.The steps the cats make become slower and shorter the closer they become to one another.