Communication is more than just speaking from our mouths, it's about whole the body communicating. Even the
shoes you wear can relay information about you. When you speak you are relaying information by the way you hold your mouth, where your eyes are looking, what you are doing with your hands and even where you place your feet. Speaking on the phone is more challenging than face-to-face and anyone who is learning a foreign language will be able to testify to this fact. In the early days of learning a new language, we rely heavily upon bodily gestures and position. We might even be tempted to act out the task we are trying to communicate. Children also know this well, whilst their language is limited. They will typically be active for much of the time. Over the years, as the language develops, it's almost as though our body plays a lesser role, as our speech manages aptly without it.
