Many members of other genera and families of rodents can also be referred to as rats as they share a number of features like that of true rats. They’re different from mice and must be confused together. Rats are large muroid rodents while mice are little muroid rodents. Muroid family is a really complex family and the terms rat and mice aren’t taxonomically relevant.
The best known species are the Black rat Rattus rattus and the Brown rat Rattus norvegicus. These species are commonly known as Old World rats or true rats and they originated in Asia. They are larger than Old World mice which weigh hardly 500 grams. The term rat is also used for some small animals which are not true rodents for example, kangaroo rats, bandicoot rats and North American pack rats. They’re also rodents but do not belong to the genus Rattus. Males are known as bucks, unmated females are called as does and the pregnant females are known as dams. The young ones are known as kitten or pups. A group of rats can be termed as pack or mischief. In some developed countries the domesticated rat species have been kept as pets in houses. R. norvegicus is commonly kept as pet and it originated in China and spread to Europe and finally in the New World. Pet brown rats are also known as fancy rats.
The common species act as commensals as they live human surroundings. Such cause tremendous damage of the stored food products. Many species of brown and black rats have become endangered due to loss of natural habitats. Wild rats are known to be carriers of a range of parasites and pathogens like Toxoplasma gondii. Many species act as vectors of the Rat flea and are responsible for the spread of plague and other related diseases. Specially bred species are kept as pets since the 19th century. Pet species do not cause any type of damage to other pet animals like dogs and cats.
Brown rats are often used as model organisms in scientific research. With the publication of Rat Genome Sequence Brown Rat is now a very useful genetic tool. Domestic species differ from wild ones in many of ways. They are calm and hardly bite and are able to tolerate crowding into a greater extent. Rats are consumed as food by people and sometimes eaten in emergency conditions too. Bandicoot rodents are the famous foods of some Southeast Asian areas. Their meat is a good source of protein. Rattus rattus and the rat flea Xenopsylla cheopis are very notorious for their distinguished role in the transmission of bubonic plague.
They have a unique role in both culture and religion. In India it is considered as the vehicle of Lord Ganesh. Their statue is always found in the Ganesh temple. In the Chinese culture it’s first of the twelve animals of Chinese zodiac. European association with rats is strongly negative. Rats act as substitute for vulgar interjections in the English Language. They’ve been hated as they act as vectors for a range of disease causing agents and have dirty habits. One of the famous stories about rats is The Pied Piper of Hamelin in which a rat catcher saved the town from rats with the magical tune of his flute. The genus Rattus at present contains 64 species.
They are both beneficial as well as harmful.