rat

Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, with the genus Rattus containing the most familiar rats. Other rat genera include Neotoma, Bandicota and Dipodomys. Among the most well-known rats are the black rat and brown rat, both of which are native to Asia. Rats belong to the same subfamily as mice and are often distinguished based on their size. Usually the common name of a large muroid rodent will include the word "rat", while a smaller muroid's name will include "mouse". The common terms rat and mouse are not taxonomically specific. Like mice, they are known to invade properties for food, water, warmth, and shelter. There are 56 known species of rats in the world.