Why "Who's a Rat" Is Suddenly Everywhere – The Truth Revealed - Away State Journal
Rats are typically distinguished from mice by 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. There are 56 known species of rats in the world. [1]
Rat, the term generally and indiscriminately applied to numerous members of several rodent families having bodies longer than about 12 cm, or 5 inches. (Smaller thin-tailed rodents are just as often indiscriminately referred to as mice.)
Some rodents that we call “rats” are not true members of Rattus, including the pack rat, naked mole rat, and giant pouched rat.
The term “rat” encompasses several species within the family Muridae, the largest family of mammals. The most familiar species is the brown rat (Rattus norvegicus), also known as the Norway rat, and the black rat (Rattus rattus), often called the roof rat.
With nearly 60 species of rat discovered so far, these rodents come in all sizes. They are typically 5 inches (12 centimeters), or longer, according to Encyclopedia Britannica.
In many regions and in scientific/laboratory contexts, the most commonly implied "rat" among true rats (Rattus) is the brown rat due to its global commensal presence and extensive use in research.
From the enormous African Giant Pouched Rat that sniffs out landmines to the bizarre Blind Mole Rat that spends its entire life underground without ever seeing daylight, rat diversity spans an astonishing range of sizes, behaviors, and ecological roles.
