Fact
Goosebumps are a leftover from having fur
Your body is trying to fluff up a coat you no longer have.
Tiny muscles at the base of each hair contract in cold or strong emotion, raising the hair. In furred mammals this traps air for insulation or makes the animal look larger to a threat. In humans, with sparse body hair, it accomplishes nothing at all – a reflex outliving its purpose by millions of years.