[5] Pacas are large rodents with dots and stripes on their sides, short ears, and barely visible tails.

Pacas are eaten by people in Belize, where they are known as "gibnut" and, having been served to Queen Elizabeth II, "the royal rat".

Similar to guinea pigs, they have square heads, small ears, sides patterned with spots and stripes, and virtually invisible tails.

Predators except humans include jaguar, puma, ocelot, margay, jaguarundi, bush dog, boa constrictor, and caiman.

Population density can reach up to 70 adults per 20 ha (49 acres), and pacas often constitute some 20% of the biomass of terrestrial mammals.

They play a vital role in seed dispersal, and, with seasonal adaptations, their home ranges are often centered on a group of fruit trees.

Like rabbits, pacas are coprophagous and absorb protein and carbohydrates from specially produced moist fecal pellets.

Pacas have altered the common rodent strategy — safety in numbers — and mind their offspring carefully.

At 650–710 g (23–25 oz) at birth, the young are born in holes too small for both predators and the mother to enter, which are then covered with leaves and twigs.

They primarily live in rainforests near streams, but can also be found in a wide variety of habitats, including mangrove swamps, gallery forests near water currents, and even in public parks.

[9] The smaller mountain paca lives in the northern Andes and the Páramo grasslands, with a peak occurrence between 2,000 and 3,000 m (6,600 and 9,800 ft) above sea level.