Guinea pigs (Cavia porcellus), although not quite as cute as baby ducks, are still adorable. They look sort of like the offspring of a rabbit and a mouse, but with even less tail. They have been bred in a million different colors, patterns and hairstyles. (Or, well, as many colors as melanin will allow...which is not that many.)
No, these rodents are not from guinea and they are definitely not pigs. They are related to the wild cavies of South America. The "Guinea" supposedly comes from French Guyana - I'm sure it's a common mistake. They have a piglike build and eat a lot, but otherwise are not terribly porcine. They also make those cute little piggie noises that gave them the native Ecuadoran name of "cuy."
Cuy, cuy, cuy...
Oh, and they're food, too.
They Actually Eat That?!
Yes, they are raised for food. They were food and traditional medicine before they were pets. They were domesticated in approximately 5000 B.C. by the native peoples of the Andes mountains.
Even cats won't eat these guys.
Why on earth eat something that adorable? Rodents, guinea pigs included, are whole foods. Nature did not design them to be cute; she designed them to be food for other animals and to keep plant populations in check. Cuteness was pretty much coincidental (as you will see on today's animal) until people started messing with them.
On that note...