10 Useless Human Body Parts

The arrector pili muscle causes the phenomenon we commonly refer to as goose bumps. There are small muscles attached to our hair follicles which when contracts causes the hair to stand up. In most animals the goose bumps are a defence mechanism. When in fear the hair ends rise up to make them look bigger in hopes of deterring predators. The arrector pili muscles cannot be consciously controlled. Some experts have come up with one purpose for the contraction of the muscles and their legitimacy of staying in our body is that the ejected hair helps trap and retain hot air inside our body. But since human body has relatively very less hair to allow thermal insulation, the argument kind of falls flat.