Theories

Scientifically, we do not yet know exactly why. But there are many theories. The following is an exerpt from a website I found that had a couple of great theories on why we may have developed this embarrassing response.

Blushing is universal, as well as exclusive to humans. “Ray Crozier is a psychology professor at University of East Anglia in the United Kingdom. He's concluded that blushing evolved as a means of enforcing the social codes to which we humans must adhere for our societies to function in a friendly manner. By blushing when we're embarrassed, we are showing others that we recognize we've just misstepped socially, and that we're paying the price for it. Others who see us blushing after an awkward situation understand from experience the unpleasant feelings we're undergoing at that moment, and blushing may serve as a nonverbal, physical apology for our mistake.

Crozier tells the BBC that embarrassment displays emotional intelligence. "A prerequisite for embarrassment is to be able to feel how others feel -- you have to be empathetic, intelligent to the social situation" [source: BBC].

This empathy and social intelligence appears to develop in humans at an early age, around the time we enter school and we begin to engage in social situations with others . By studying the development of this social intelligence, psychologists have found that blushing from embarrassment develops alongside our consciousness of others. This lends further support to the notion that blushing has a purely social basis.

If the phi­losopher Thomas Hobbes was correct in his description of early societies as being "nasty, brutish and short" [source: Hobbes], then blushing may have developed as a means for displaying genuine regret over an insult to someone else. Since we humans are animals, too, a glance at our neighbors on the Tree of Life shows us that insults can lead to violence. As a result, animals have developed ways of displaying apologetic signs to show others they're sorry for what they've done.

Think about your dog rolling over after being caught digging in the yard. Exposing his or her belly to you shows you the dog is not challenging your anger at the situation -- it's a demonstration of contrition. For most people, it's pretty difficult to continue to feel anger toward the dog once he or she has rolled over. So blushing could be a way humans show their own contrition for bad social form.

Another interpretation suggests that blushing is the opposite of contrition; it's the appearance of rage. This explanation posits that blushing is the result of one aspect of your personality coming under assault. The NPA theory of personality (Narcissism, Perfectionism, Aggression) says that three components form the basis of all personalities. These components can occur in varying degrees to form a variety of different personality types. The narcissistic (N) aspect is based on a quest for glory and recognition among one's peers. When this quest is derailed publicly -- say through an embarrassing situation -- we experience the surge of adrenaline and the ensuing blush.

 Regardless of what proves to be the ultimate explanation for why we blush, people seem to have developed an aptitude for forgiveness alongside their physical response to embarrassment -- if we hadn't, there'd be no reason for blushing. So the next time you suffer an awkward situation of your own making and feel your cheeks grow warm, just remember -- this, too, shall pass." (Clark 2013).

So, based on these theories we can propose that blushing may or may not be directly related to social intelligence, feeling shameful or being angry. Regardless of the true meaning to why we have developed this response, it is universal among humans and we all have experienced it at one point or another.

"Why do people blush?" science.howstuffworks.com/life/blush1.htm