Why do we get goosebumps?

One rainy afternoon, Na ran in from the yard, her shirt wet and cold, the fan blowing on her arms. Her arms came up in tiny bumps, rough to the touch.

Cú Bông guessed her skin was shrinking in the cold, like the peel of an old apple.

That evening, in dry clothes and wrapped in a warm blanket, Na listened to Dad tell a ghost story. At the scary part, the bumps came back, though she wasn't cold at all. Through a magnifying glass, Na saw a fine hair standing up in the middle of each bump.

Beside many hairs in your skin is a tiny muscle. When it tightens, it pulls the hair upright, and the skin around it rises into a little bump. When lots of these muscles tighten at once, a whole patch of skin comes up in goosebumps.

Goosebumps often come when we are cold. When we are frightened or feel something strongly, the body releases adrenaline, which can make those muscles tighten too.

Pick each scene to compare Na's arm. Which two scenes give the same bumps for different reasons?

Goosebumps happen when the tiny muscles beside our hairs tighten and pull the hairs upright. Cold, or a strong feeling such as fear, can bring them on.