Do wild guinea pigs exist?

You might be surprised to hear this, but, yes, they do!

The guinea pig (cuy) is a species of rodent that's part of the genus Cavia in the family Caviinae. There are at least five currently recognised wild species of guinea pig, including the Brazilian cavia aperea. This species can be found across South America in countries such as Brazil, Colombia and Venezuela. There's also the Andes-dwelling montane guinea pig (cavia tschudii).

Guinea pigs are indigenous to South America, and it's believed domestication occurred in the Andes around 6,000 years ago. It was as a result of wild guinea pigs being taken in as pets and for food that the species of guinea pig we have as a pet today evolved.

It is believed the cavia tschudii is most likely to be the main ancestor of the domestic guinea pig (cavia porcellus). And that the domestic guinea pig is a hybrid of other Cavia species. So, it’s clear that the domestic guinea pig has been bred by humans and did not evolve naturally.

Where do wild guinea pigs live?

We know wild guinea pigs are native to South America, but what kind of conditions do they live in? Well, the habitats of wild guinea pigs range from dry, rocky, high-altitude meadows to marshy, tropical floodplains. And when it comes to what they eat, their diet mostly comprises plant material like grasses and herbs.

Both the cavia aperea and cavia tschudii have stable populations, with fathers involved in the bringing up of the offspring. Cavia tschudii live in smaller groups with one or two boars and three to five sows on average in a sort of colony. The boars are much more willing to fight it out, and the hierarchy is fiercely observed.

The state of Santa Catarina in South Brazil is home to a rare guinea species, with a population of around 42. The species evolved several adaptations to survive island life, after their ancestors left the mainland about 8,000 years ago because of rising sea levels. Unfortunately, because this species has such a small population size and low reproductive rate, hunting and natural disasters pose very real threats.

How do domestic guinea pigs differ from wild guinea pigs?

One of the most obvious differences is the appearance of domestic guinea pigs. We all love that there are so many piggy breeds because it means we get them in a variety of colours (and hairstyles!) but wild guinea pig fur tends to be a uniform pale to dark brown with pale to dark grey underparts. This is likely because shades of brown best help camouflage them against predators.

The wild cavia tschudii also tends to be smaller and lighter, weighing on average 500g to 600g. This is very different to the average pet guinea pig which tends to weigh anywhere between 700g and 1500kg. This is likely due to our piggies being descended from wild guinea pigs that were used as a source of food.

It's no surprise that as a result of domestication by humans, guinea pigs have developed behaviours that their wild counterparts do not exhibit. Pet guinea pigs are more sociable, less stressed and therefore less aggressive because they do not have to compete for food, etc. They also don't face the threats that wild guinea pigs do, such as predation and natural disasters.

Pet guinea pigs also make sounds that wild guinea pigs don't, or the reasons for making them differ. Wheeking is a prime example. We know that our piggies will wheek their little heads off when they think food is around or on the way. They're basically saying “feed me!” Wild guinea pigs do wheek, but it's probably more as a fear or alarm response. This article goes into more detail about the differences between wild and domestic guinea pigs and is well worth a read.

A Montane Guinea Pig (Cavia tschudii) with her pups. Photo by José Tomás Urrea (click for image source) © José Tomás Urrea

Summary

So, wild guinea pigs do exist and still live throughout South America today. And it was the domestication of the wild guinea pig around 6,000 years ago that eventually bred out the cavia porcellus species. Which is the species we now know and keep as pets.

While our pet piggies have little resemblance to wild species, isn’t it amazing to think they are all ultimately descended from the wild guinea pig? Makes us love our little bundles of fluff even more!