Hamsters are the guinea pigs of pets
Hamsters are the guinea pigs of pets This joke is a pun centered around the use of the word "guinea pig". Guinea pig can mean a specific animal of the species Cavia porcellus, but the word can also be used to denote that something is a test subject (because guinea pigs are traditionally used in animal testing in laboratory settings.) The phrase "A is the B of C" means if you were to take object A from category C, and compare it to an object in a different category it would be the most like object B. For instance: "Parmesan is the Mercedes-Benz of cheeses", which means that if Parmesan cheese were a car, it would be a Mercedes-Benz, since it is excellent. So, given those things the joke could mean (if you use the word guinea pig colloquially as a test subject) "people get hamsters because they want to test out the idea of having a pet". This is something that actually does happen - I myself have told kids that if they want to test out what having ...