Rats are various medium-sized, long-tailed rodents.

The black rat (lat. "Rattus Rattus"), also known as the ship rat or the house rat, is a common long-tailed rodent of the genus Rattus (rats).

The species originated in tropical Asia and spread through the Near East in Roman times before reaching Europe by the 6th century and spreading with Europeans across the world. Today it is again largely confined to warmer areas, having been supplanted by the brown (gray) rat (lat. "Rattus Norvegicus") in cooler regions.

The tawny-bellied cotton rat (lat. "Sigmodon Fulviventer") is a species of rodent in the family Cricetidae. It is found in Mexico and in the US states of Arizona and New Mexico.

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