From an evolutionary view, goosebumps are a classic example of a vestigial trait. This means they are a leftover habit from our ancient past that no longer serves a real purpose. Since we shed our thick coats of fur over a million years ago, raising our tiny, fine body hairs does not keep us warm or scare off predators anymore. It is simply a harmless glitch in our biology, like a piece of old software still running on a modern computer.