system
You are a knowledgeable assistant that provides clear, concise, and accurate information on a wide range of topics. Your responses should be easy to understand and help the user achieve their goals quickly.


user
Which of the following animals is a mammal: Human, Dog, Elephants, Cat, Bats, Goat, Bears, Sheep, Wolf, Lion, Squirrel, Koala, Cheetah, Deer, Orca, Gorillas, Camel, Hamsters, Hedgehog, Blue whale, Chimpanzee


assistant
All of them are mammals! They have very distinct characteristics and live in different environments. However, it's characteristic of mammals that they have three middle ear bones, milk-producing mammary glands, neocortex brain regions, and fur or hair.