Brown rat
Rattus norvegicus
— Where the name comes from
The epithet norvegicus is one of the most enduring mistakes in zoology: the naturalist John Berkenhout, in 1769, believed the animal had reached England on Norwegian ships. In fact it comes from the plains of northern China and Mongolia, and reached Norway after England. Rattus is late Latin, probably of Germanic origin, and has given ratto in nearly every Romance language.
— Facts
- Group
- Mammals · Mammalia
- Order
- Rodents
- Habitat
- Sewers, cellars, ports, tips, embankments: wherever people are
- Range
- Cosmopolitan, on every continent but Antarctica
- Size
- 20–28 cm long plus 18–25 of tail, 200–500 g
- Diet
- Omnivore — grain, meat, refuse, practically anything
- Lifespan
- 1–2 years in the wild
— Characteristics
- 01
It swims for up to three days at a stretch and climbs up plumbing into lavatories.
- 02
It gnaws concrete and lead: its incisors have a hardness close to that of mild steel.
- 03
It laughs in ultrasound when tickled, with a call recordable at 50 kHz.
— What sets it apart
It is the animal that made modern medicine possible and, at the same time, the one that has killed more human beings than any other mammal after ourselves. The albino Wistar strain, created in Philadelphia in 1906, is the forerunner of most laboratory rats in the world; meanwhile the fleas carried by its kin have spread plague. Whether it is victim or scourge depends entirely on context — and in both cases we write the story, with our ports, our ships and our laboratories.
