1. Why are the muscles that make hair stand up vestigial?

2. what are the probable functions of the muscles that makes hair stand up?

1 answer

The muscles that make hair stand up are vestigial because they are remnants of a trait that was once useful in our evolutionary ancestors, but is no longer necessary in humans. These muscles, known as arrector pili muscles, were once used to help animals fluff their fur in order to make themselves appear larger and more intimidating to predators. In humans, these muscles are still present, but they no longer serve any purpose.

The probable functions of the muscles that make hair stand up are to help animals fluff their fur in order to make themselves appear larger and more intimidating to predators. This is a behavior that is still seen in some animals today, such as cats and dogs. Additionally, these muscles may also help animals regulate their body temperature by trapping air close to the skin.