Goosebumps<>happen<>when mammals raise their hair with tiny muscles in the skin$$$mammals<>raise<>their hair
When you get goosebumps a small muscle at the base of a hair contracts to cause the hair to stand-on-ends .
Goosebumps happen(s) when mammals raise their hair with tiny muscles in the skin.
What happens when mammals raise their hair with tiny muscles in the skin?