• The capibara's jaw joint allows chewing forward and backward, unlike most mammals that chew side to side. This feature helps them efficiently chew plant food even in winter, when it is less nutritious.
• Capibaras have sweat glands on the surface of fur-covered skin areas, an unusual feature among rodents. They lack underfur, and their guard hairs are barely different from the rest of their fur.
• The capibara's premolars and molars lack roots and grow throughout its life. Its incisors are wide and have a longitudinal groove on the outer surface.

The capybara pup is born covered in fur that dries quickly after being in water, and possesses short legs with membranes between the toes to aid swimming. The species has a large head with a short muzzle, and its eyes, ears, and nostrils are positioned high on the head for easy breathing while swimming. An adult capybara has a heavy, barrel-shaped body covered in coarse, sparse fur and four legs with small membranes between the toes, which allow for swift swimming and comfortable walking on soft ground. The adult’s sharp incisors grow continuously, assisting in the consumption of tough grasses and bark.