Palms sweaty, heart racing, too panicked to even breathe? No, you aren't being stalked by some monster ): you're about to speak in public!
While some would claim public speaking is a fate "worse than death," public speaking might actually feel worsethan death: at least you won't feel stage fright in death! If public speaking is so nerve-racking, do genetics cause social anxiety?
At some point in your life, you will have to communicate in front of people. Learning what stage fright really is could make you more comfortable doing so. Basically you, as a human, are wired to care about your reputation or what people think of you. So what happens if you get up there and forget a few lines or completely bomb a speech? This fear of being considered an idiot by your peers is a natural instinct called the flight or fight response, a primitive function in your brain that acts to self-protect at all times. The flight or fight response is a very difficult thing to control. Though it's present in all animals, most creatures don't have to get up in front of the entire animal kingdom to make any speeches!
Via Vicki Kossoff @ The Learning Factor