Even rats hate rats

The other day I was getting take-out from my very favorite Italian place near here, Max's Soha, when I heard a scream and a squeak. I looked down and saw that four rats were getting into it, having an all-out brawl, right on the street corner near a stairwell, just flogging each other with their tails, clawing, fisticuffs all around, fur flying, literally. It went on for a very long time and they finally scattered in all directions. I guess even rats can't stand rats, which is sad when you think about it. I spend so much time being disgusted by putrid, fat, stinking rats that I forget they are sentient mammals, with self-esteem issues and concerns like everybody else. You'd think rats would be united with an 'us against the world' attitude toward us humans, but being vermin has taken its toll on their self-image. Their response is to brawl in the streets.