The degu is a small animal with a body length of 25.0 to 31.0 centimetres (9.8–12.2 in) and a weight of 170 to 400 grams (6.0 to 14.1 oz. It has yellow-brown fur above and creamy-yellow below, with yellow around the eyes and a paler band around the neck.
Degus are strictly herbivorous, in the wild feeding on grasses and browsing the leaves of shrubs, though they will also take seeds.
Perhaps the most remarkable feature of degu physiology is their intolerance of dietary sugar.
Although they are active by day, in high summer they do not leave their burrows in the middle of the day and instead emerge to forage in the mornings and evenings.
Degus entered the research spotlight due to their unique relationship with sugar and diabetes, but are also studied for a wide variety of other reasons.
Another interesting area of degu research is circadian rhythm function, i.e. the ability of the brain to tell what time of day it is.
In elderly degus, neural markers have been discovered which are remarkably similar to those in humans with Alzheimer's disease, which is the first time this has been seen in a wild-type rodent
small mammal native to Chile.