RAT

Rats are various medium-sized, long-tailed.Rats  are typically distinguished from mice by their size.The term "rat" is also used in the names of other small mammals which are not true rats.
           
                 Male rats are called bucks, unmated females are called does, pregnant or parent females are called dams, and infants are called kittens or pups. A group of rats is referred to as a mischief.
             Rats are a common food item for snakes, both in the wild, and as pets.

              Domestic rats differ from wild rats in many ways. They are calmer and less likely to bite; they can tolerate greater crowding; they breed earlier and produce more offspring; and their brains , livers ,kidneys, adrenal glands , and hearts are smaller

                Over the years, rats have been used in many experimental studies, which have added to our understanding of genetics , diseases , the effects of drugs , and other topics that have provided a great benefit for the health and well-being of humankind. Laboratory rats have also proved valuable in psychological studies of learning and other mental processes
               The average lifespan of any given rat depends on the species  but many only live about a year due to predation.