What causes Goosebumps?

Certain situations like a temperature drop, a strong feeling of fear – a strong emotion results in us getting goosebumps. When we experience a strong emotion like fear, our brain sends a signal to our muscles that make them tense up. When the muscles in our skin that are attached to hair tense up, they make the hair pull our skin, creating a layer of insulation- thus creating goosebumps.

Why are Goosebumps called Goosebumps?

They are called goosebumps because when they emerge your skin looks like that of a goose whose feathers have been plucked!
Our ancestors were very hairy. They experienced a pilomotor reex common in animals that made the animal look bigger when
goosebumps appeared. This helped them scare many enemies. As humans evolved, body hair became lesser and the reex had more
to do with muscles now.