Today, the guinea pig you’re most likely to recognize is the domestic species, Cavia porcellus. However, this species is not the only cavy around. The evolutionary history of guinea pigs is fascinating, and today’s domestic varieties have wild cousins.
Evolutionary Ancient History
Guinea pigs can trace their ancestry back to the late Miocene period, which is somewhere between seven and twenty-six million years ago. At the time, there were marmot sized critters called paramyids. These creatures evolved in several distinct directions, including the Caviidae family.
The Divide from Wild Guinea Pigs
Domestic guinea pigs, Cavia porcellus, shared evolutionary history with the rest of the species until somewhere between 5000 and 2000 BCE. At this point, humans in the Andes began domesticating guinea pigs. Cultures across the Andes have diverse uses for guinea pigs.
It was rare that guinea pigs were bought, and instead, they were often gifted for special occasions. Guinea pigs were usually allowed to roam free in the kitchen area and were fed from scraps. This exchange of guinea pigs prevented too much inbreeding.
Guinea pigs were also deliberately bred. In many Andean cultures, guinea pigs were not only gifts. They were also eaten on special occasions. Selective breeding allowed people to change their taste, as well as the look of guinea pigs given as gifts.
Some cultures also assigned the guinea pig a medicinal purpose as an evil spirit catcher. Traditional medicine held that guinea pigs could determine where the spirit was sitting in the body. The treatment involved moving the guinea pig over the patient’s body and finding the spot where it squeaked loudest. Then the guinea pig laid on that spot for a while. Black guinea pigs, in particular, were favored for this practice.
The Spanish Conquest
The Spanish conquest also played a role in the evolutionary history of guinea pigs. This change shipped guinea pigs across the Atlantic throughout the 1600s. This distance created separate gene pools, though the export of guinea pigs didn’t cease.
The other thing the Spanish conquest did for the evolutionary history of guinea pigs is replacing traditional practices. Since the spread of the Spanish meant the spread of Christianity, many cultural practices ceased. Guinea pig healing and gifting altered radically during this time, which in turn affected breeding.
Modern Guinea Pigs
Today, guinea pigs exist all around the world. The domestic variation is incredibly prevalent, and these hardy critters flourish. Many breeders’ associations devote themselves to guinea pigs and the several recognized breeds under Cavia porcellus.
The domestic guinea pig has several wild cousins around the Andes. These are genetically distinct varieties, some of which are quite rare. For example, a 2008 survey showed the Moleques do Sul Guinea Pig (Cavia intermedia) has less than 50 wild members. Most guinea pigs are at no risk of disappearing.