Eat and/or be eaten

At the pet store.
Employee: "The rule of thumb is that if a fish can fit another fish into their mouth it pretty much will."

A new breed?

At the pet store.
Small boy: "Nana, nana, look! What's dat? What's dat?"
Woman: "It must be a rat squirrel or something like that."

Beastly Body Image

At the pet shop. Small girl with her parents.
Mother: "How about this gerbil? Should we get this one?"
Girl: "No, his butt sticks out too much."