They eat our food. They furnish their nests with our detritus. They chew through our sheet metal, our lead pipes and our concrete. They outsmart us at every turn. They are our shadow, our enemy, our next door neighbor. —”Rat City!” Spy magazine, 1988

http://phenomena.nationalgeographic.com/2015/08/14/yes-rats-can-swim-up-your-toilet-and-it-gets-worse-than-that/