Are Degus Rats? (Understanding Classification of Degus)

As you’ll probably already know, degus are rodents. They have a particular appearance that distinguishes them from other pocket pets. But to people that know little about degus, they can be mistaken for rats. So, are degus rats, or are they related to rats in a way?

Degus aren’t rats and aren’t closely related to rats. Degus belong to the parvorder Caviomorpha and are related to chinchillas and guinea pigs. Rats belong to the parvorder Myomorpha and aren’t related to degus. Both degus and rats are rodents (order Rodentia) and do share certain characteristics.

Although degus aren’t mice or rats, the name ‘degu’ is derived from the indigenous word dewü, meaning ‘mouse’ or ‘rat’.^[1]Muñoz Urrutia, Rafael, ed. (2006), Diccionario Mapuche: Mapudungun/Español, Español/Mapudungun (in Spanish) (2nd ed.), Santiago, Chile: Editorial Centro Gráfico, pp. 104, 105, 141

But degus aren’t directly related to rats; they are part of the larger ‘family’ of rodents. So what makes a degu more closely related to chinchillas and guinea pigs and what are the differences between a degu and a rat?

Degus and Other Caviomorphs

The parvorder Caviomorpha is a kind of suborder of the larger order of rodents (Rodentia). The caviomorphs are thought to be the first rodents in South America.^[2]Defler, T. (2019). The Caviomorphs: First South American Rodents. In: History of Terrestrial Mammals in South America. Topics in Geobiology, vol 42. Springer, Cham. … Continue reading The chinchilla and guinea pig are also part of this parvorder and share certain characteristics with the degu.

But the caviomorph does not only include degus, chinchillas, and guinea pigs. The following animals are also caviomorphs:

• hutias
• capybaras
• chinchilla rats
• viscachas
• tuco-tucos
• agoutis
• pacas
• pacaranas
• spiny rats
• New World porcupines
• coypu

Below you can find different images of caviomorphs.

As you can notice some of these animals look alike, while others look very different. The same goes for degus. Degus don’t look like chinchillas and guinea pigs, but they share certain characteristics.

Differences Between Degus and Rats

Physical differences

Degus have round bodies and typically brown fur, although different color variations are known. In addition, most degus have a band around their eyes, accentuating them and differentiating them from the rest of their furry body.

Rats, on the other hand, have a more thin and elongated body. They are also known in different color variations but don’t have a band around their eyes.

Degus have furry tails with hair tufts on the tip. Rats don’t have much hair on their tail. Their tails look bald but actually contain fine short hairs. The tip of a rat’s tail doesn’t have the distinctive tuft you’ll see on degus.

Size differences

Degus typically weigh between 170 and 300 g (0.37 and 0.66 pounds), while rats weigh a bit more and average between 450 and 650 g (1 and 1.43 pounds). Rats are a bit heavier, but they’re also longer.

Degus can reach a length up to 15 cm (5.9 inches), while rats will grow up to 28 cm (11 inches). In both cases, the tail is not included in the measurement.

Want to Learn More?

If you’re interested in learning more about degus as pets, please read the following articles:

• Complete and illustrated degu diet guide
• Degus vs fancy rats: which pet is suitable for you?

If you’re interested in getting degus as pets, you should read our beginner’s guide to keeping degus as pets and our degu care guide.