Why do we get Goosebumps?
Stand outside in the cold or watch a horror movie, and you might
see the skin on your arms look bumpy as the hairs stand up. We call this
"goosebumps," but the medical name is cutis anserina.
Goosebumps happen when the tiny muscles in each hair follicle, called
arrector pili muscles, contract, says Dr. Jennifer Holman, a
dermatologist at University of Missouri Hospital Many other animals,
including your cat or pooch, get goosebumps too. In the cold, goosebumps
serve to pull the hair upright creating an insulating layer of hair and
warm air around the body. If an animal is afraid, pulling the hairs up
makes the animal look larger and may scare away other animals.