GOOSE BUMPS. “Piloerection, leading to ‘goose bumps’ or ‘goose pimples,’ can be considered a vestigial phenomenon in mostly hairless humans, and the arrector pili smooth muscles that pull on hair follicles and cause this autonomic reflex can be viewed as vestigial structures.”
https://evolution-outreach.springeropen.com/articles/10.1186/s12052-014-0012-5