h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

In the Andean Region of South America, guinea pigs or cuys as they are called locally are in fact a delicacy. I was aghast at the fact (I had a pet guinea pig as a child) at first, but then again, this is still a major protein source for the Andean indian groups, who raise the cuys often in their houses, letting the animals scurry around underfoot and feed on fallen table scraps, etc.

Strider25

This is why they are so friendly and easy to keep. The ones that we keep for pets are not directly descended from wild animals but are genetically modified by artificial selection.

Like most domestic animals they have little ability to evade predators.