We feel them. We see them. But why do we get them?
The physiological reaction commonly known as goosebumps occurs when small muscles attached to individual body hairs contract, which leads the hair to stand on end.
George A. Bubenik, a physiologist and professor of zoology at the University of Guelph in Ontario, Canada, provided his research to Scientific American.
There, Bubenik explains how goosebumps were passed along genetically from our ancestors. They used the reaction as a way to retain heat, and he also argues that goosebumps allowed humans to appear bigger than they were to fend off predators.
With modern humans having less body hair, goosebumps no longer serve less in terms of functionality but still provide for good banter in our everyday lives.