Rat

The  is a type of animal. This animal is a warm-blooded, long-tailed rodent in the genus Rattus. Rats are a prey animal for snakes. Rats are known to Vault residents from the books supplied by Vault-Tec to the Vaults.

On July 13, 2268, as Butch DeLoria and his friends discuss possible names for their gang, Mr. DeLoria suggests "Tunnel Rats" as a cool name for their gang. Wally Mack replies, "Usually, snakes eat rats and lizards." Faced with this response, Mr. DeLoria says never mind and asks his friends for other names.