To which species does the rat belong? - briefly
Rats belong to the genus Rattus within the family Muridae of the order Rodentia; the primary species are the brown rat (Rattus norvegicus) and the black rat (Rattus rattus).
To which species does the rat belong? - in detail
Rats are members of the mammalian order Rodentia, placed within the family Muridae, which encompasses the true mice and rats. Within Muridae they belong to the subfamily Murinae, the Old World rats and mice, and are classified under the genus Rattus. This genus contains several species, the most widespread being the brown rat (Rattus norvegicus) and the black rat (Rattus rattus).
Taxonomic hierarchy for a typical rat:
- Kingdom: Animalia
- Phylum: Chordata
- Class: Mammalia
- Order: Rodentia
- Family: Muridae
- Subfamily: Murinae
- Genus: Rattus
- Species: Rattus norvegicus (brown rat) or Rattus rattus (black rat)
The family Muridae is distinguished by a set of dental and skeletal features: a single pair of continuously growing incisors in each jaw, a robust skull, and a flexible clavicle that permits a wide range of locomotion. Within the genus, species differ in size, coat coloration, tail length, and habitat preference. The brown rat typically exhibits a larger body, a blunt tail, and prefers temperate climates and urban environments, whereas the black rat is smaller, has a longer, more slender tail, and thrives in warmer, tropical regions.
Molecular phylogenetic studies confirm that Rattus shares a recent common ancestor with other Murinae genera such as Mus (true mice) and Apodemus (field mice). Genetic analyses reveal low mitochondrial DNA divergence between R. norvegicus and R. rattus, supporting their classification as sister species within a monophyletic clade.
In summary, rats are classified as rodents of the Muridae family, subfamily Murinae, genus Rattus, with the brown and black rat representing the primary species encountered worldwide. Their taxonomic placement reflects both morphological traits and molecular evidence that link them closely to other Old World rodents.