Guinea Pig Profile
South America is home to some of the most exceptional rodents on the planet.
It’s thought that five tiny animals drifted to what was at the time an island continent, floating across from Africa to radiate into the new ecosystem and diversify into some incredible species.
Among them, are the giant capybara, the fawnlike mountain paca, and a familiar animal that’s not from Guinea, nor remotely related to a pig.
Guinea Pig Facts Overview
| Habitat: | Savanna, montane, grassland, marshes |
| Location: | South and Central America |
| Lifespan: | 14 years in captivity |
| Size: | Up to 25 cm (10 inches) long |
| Weight: | Up to 1.2 kg (2.6 lb) |
| Colour: | Varied |
| Diet: | Herbivorous |
| Predators: | Raptors, |
| Top Speed: | Slow |
| No. of Species: | 6-10+ |
| Conservation Status: | Least Concern to Critically Endangered (IUCN) |
The name Guinea pig has a bit of a mysterious origin, but Guinea in this context is likely just a euphemism for “far away”. The pig part is harder to explain, but this might be a comment on the squeaks they make.
These calls are part of a wide repertoire of vocalisations, reflecting the sociality and intelligence of this medium-sized rodent.
Guinea pigs make up between 6 and 10 species, dotted about in various ecosystems in South America. Some are solitary and elusive, others hugely social and prevalent.
Interesting Guinea Pig Facts
1. They’re not just pets
When we think of guinea pigs, most of us think of the adorable little squeaky slippers that school classrooms used to have before allergies became a thing.
As a pet, the guinea pig is widely popular on account of them being docile, adorable, and smart. But this is just a slither of the guinea pig population worldwide, and there are possibly nine or more other wild species that deserve just as much recognition.
Also known as cavies, guinea pigs occupy a range of niches as adaptable rodents, some doing the same work as cattle in particularly grassy regions, converting plant matter into nutritious poop.
Others are more solitary and live underground. 1
2. Some are tunnelers
Many species will occupy burrows given to them by another animal, but the greater guinea pig digs its own.
This is a solitary species and creates large tunnel and runway networks through its vegetation ranges in eastern Uruguay and south-eastern Brazil. 2
3. Others are herd animals
Some species are far more social, forming huge herds of formidable herbivorous presence. These herds usually contain many females, a dominant male, and their offspring. These prefer wide plains and will spend a lot of time feeding, grooming one another, and chattering away.
These herds are ecologically significant, not only because of the pressure they exert on the vegetation but from all the food they provide to bigger animals. 3
4. Some are critically endangered
For 8000 years, a species of guinea pig has existed on a tiny 10-hectare island off the coast of Brazil. It’s thought there are now between 24 and 60 mature individuals and they may be in decline.
Interestingly, in the 8000 years that they’ve existed here, the Santa Carina guinea pig population has likely never been bigger, and there are no predators on the island and no other competitive herbivores.
But this species only exists here, and is totally dependent on two species of grass, which it eats voraciously. This is a strange case where a species isn’t under any new threats, but is so vulnerable that it could disappear any moment! 4
5. They’re food animals
These animals feed a lot of large predators, and humans are no exception. The first domesticated guinea pigs likely came about 7000 years ago somewhere in the tribes of the Andes.
These tasty little rodents were so well respected that they show up in ancient artwork from the Moche people in Peru, and have had a long history of providing meat for local people.
But they also support the wider predator community in the same way. Able to breed all year round, these are classic rodents who can explode quickly into large numbers. As such, they’re a major source of protein for all sorts of predators from cats to owls, snakes, coyotes, and more or less anything that can catch them.
And for humans, they’re even more significant.
6. They’re research subjects
Since the 17th Century, similarities between guinea pigs and humans were recognised as enough to warrant various tests being run on the rodents.
This species has been more or less replaced by rats and mice now, but the origin of the term “guinea pig” as a test subject stems from their lengthy tenure as recipients of unthinkable torment in the name of science.
Some are still used to this day, and the animal testing landscape remains one of the dirtiest secrets in animal ethics.
While it’s undeniable that their suffering has contributed to huge gains in human medicine – the discovery of adrenaline was thanks to such testing – a vast amount of testing is either for non-essential purposes or results in no gain whatsoever, and this tragic reality is compounded by just how lucid and smart these animals are. 5
7. They’re smart
People who’ve kept them as pets will attest to how quickly guinea pigs can be trained. An excited squeal as you open the fridge door, a gentle purr when they’re picked up and cuddled, or a satisfied mumble while eating pumpkin all suggest that these are very aware and emotional animals, and highly social.
Guinea pigs do well with friends and each has its own personality, as is the case among all rodents, even the less popular rats and mice.
When very excited, they explode up into the air like a startled gazelle, bouncing about in a behaviour known as popcorning.
8. They make cute noises
Much of the guinea pig’s behaviours are accompanied by one or more of a wide range of vocalisations, ranging from the excited “wheek!” to the more agitated squeals of an upset rodent.
In between, there are various sounds in its repertoire which can send messages of dominance, fear, or arousal. For a rodent, this vocal range is quite impressive, though more for the fact that their vocalisations are in the audible range, while many animals talk to one another using sounds we can’t hear.
Guinea Pigs Fact-File Summary
Scientific Classification
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Rodentia |
| Family: | Caviidae |
| Genus: | Cavia |
Fact Sources & References
- “Guinea Pig”, Science Direct.
- “Greater guinea pig”, eol.
- “Cavia cavies and Guinea pigs”, Animal Diversity Web.
- “Santa Catarina’s Guinea Pig”, IUCN Red List.
- David Adam (2005), “Why use guinea pigs in animal testing?”, The Guardian.