Domestic guinea pigs are big, tailless rodents. Males in this species are larger than females. Despite their common name, these animals are not in the pig family and they don't come from Guinea in Africa. The origin of their name is still unclear. They originated in the Andes of South America and studies suggest they are domesticated descendants of a closely related species of cavy such as Montane guinea pig, and therefore do not exist naturally in the wild. Due to a selective breeding, these animals have different hair colors and different coat textures and length.
Domestic guinea pigs are not found naturally in the wild; it is likely descended from closely related species of cavies, such as Brazilian guinea pig, Shiny guinea pig and Montane guinea pig, which are still commonly found in various regions of South America. Now they are introduced as pets in Europe and all over the world. These animals are native to grassland habits. However, they were very adaptable and could survive in different environments.
Domestic guinea pigs are social and thrive in groups of two or more individuals. Groups of females, or groups of one or more females and a neutered male are common, but males can sometimes live together. They are crepuscular animals, being active during dusk and dawn. Guinea pigs can jump small obstacles but are poor climbers, and are not agile. When they sense danger these animals either freeze in place for long periods or run for cover with rapid. When happily excited, guinea pigs may repeatedly perform little hops in the air (known as "popcorning"). They are also good swimmers. Guinea pigs often self-groom and may sometimes participate in social grooming. Dominance within male groups is established through chewing each other's hair, biting (especially of the ears), aggressive noises, head thrusts, and leaping attacks. Guinea pigs communicate through a variety of noises, including wheeks, rumbling, bubbling or purring, chattering, squealing or shrieking, chutting and whining.
Little is known about the mating system in Domestic guinea pigs. Females are able to breed year-round, with the peak in spring. A sow can have as many as five litters in a year, but six is also possible. The gestation period lasts 59-72 days. Litter size ranges from 1 to 6, with 3 being the average. Newborn pups are well-developed with hair, teeth, claws, and partial eyesight. They are immediately mobile and begin eating solid food, though they continue to suckle. Females can once again become pregnant 6-48 hours after giving birth. Guinea pigs practice alloparental care, in which a female may adopt the pup(s) of another. This happens if the original parents die or are for some reason separated from them. Females nurse their young for 14-21 days until weaning. Males in this species reach maturity in 3-5 weeks, while females are able to breed as early as 4 weeks old, and can carry litters before they are adults.
The guinea pig was first domesticated as early as 5000 BC for food by tribes in the Andean region of South America (the present-day southern part of Colombia, Ecuador, Peru, and Bolivia). From about 1200 AD to the Spanish conquest in 1532, selective breeding resulted in many varieties of domestic guinea pigs. In Western society, the domestic guinea pig is very popular as a household pet, a type of pocket pet, since its introduction by European traders in the 16th century. Their docile nature; friendly, even affectionate, responsiveness to handling and feeding; and the relative ease of caring for them have made and continue to make guinea pigs a popular choice of pet. The domestic guinea pig plays an important role in folk culture for many indigenous Andean groups, especially as a food source, but also in folk medicine and in community religious ceremonies. The animals are used for meat and are a culinary staple in the Andes Mountains, where they are known as cuy. A modern breeding program was started in the 1960s in Peru that resulted in large breeds known as cuy mejorados and prompted efforts to increase consumption of the animal outside South America.