Cats purr, and it may help them feel calm and cozy.
A soft purr often means a cat is happy and relaxed while it rests.
More facts about Pets
A dog's nose print is one of a kind, like your fingerprint.
Hamsters stuff food in their cheek pouches to carry it home.
Goldfish can learn to remember things for months.
A guinea pig "popcorns" — it hops in the air when it's happy.
The tallest dogs can look a grown-up right in the eye when standing up.