Question: Why do people blush?

Bridget Waller answered on 18 Jun 2010:

Super question! Unfortunately…we don’t know. 🙂 But, Darwin thought that we only blush on the parts of our skin that others can see, and that it signals self-consciousness. Physiologically, we blush because the blood rushes to the surface of our skin to cool down (vasodilation), which is an autonomic nervous system response to feeling nervous. We don’t know if it has evolved to signal emotion, and this might be unlikely given it is more visible on lighter skins than darker skins, and thus might not be universal (common to all people).