Goose bumps, also known as goose flesh or goose pimples, are the bumps that appear on a person’s skin, at the base of each hair. They are caused when a person is feeling cold or when is experiencing strong emotions like fear, pleasure, nostalgia, admiration and etc.
The bumps are actually caused by a reflex that is known as “arising” or “the pilomotor reflex”. It is common to many mammals (including humans). The other creatures get goose bumps for similar reasons – in cold conditions these bumps help the animal to create additional warmth on it’s skin, and when the animal is frightened they make it appear bigger.