Why do we have to exhale (or inhale) in order to speak?
Every time we speak, sing, or make any other kind of advanced noise with our throats, we exhale, or to put it that way, blow air through our throats. Why is this required? After all, speakers do not need any air blowing through them, they simply vibrate the air and create the vibrations (sounds) they're supposed to. Why can't humans create (intelligible) sound just by having an organ that vibrates the air around us? Also, are there any animals that can? (None that I can think of at least). Would it be an evolutionary gain, or just rather pointless? PS: Obvoiusly we can clap out hands and the like, but that's not what I'm talking about. **Edit**: The question is not about exhaling/inhaling, but rather why we need airflow in the first place; why we cannot use a mechanism similar to that of speakers.