4.1 It exposes attention
Gaze direction, head orientation and pointing indicate what matters now. Joint attention allows two people to know that they are attending to the same object or event, an important basis for teaching, reference and coordinated action.
4.2 It externalises affect
Faces, voices and bodies make fear, pain, confidence, submission, attraction and anger partly observable. These displays can trigger rapid responses before a verbal explanation finishes putting on its shoes.
4.3 It enables immediate reference
A gesture can select that animal, this path or the tool behind you without first inventing a name. Iconic and demonstrative action provides a bridge between experience and conventional symbols. [4]
4.4 It coordinates bodies
People use posture, timing, gaze and hand movement to manage turn-taking, joint labour, caregiving, conflict and ritual. Visual bodily signals are core devices for coordinating minds, not decorative subtitles beneath the allegedly real message. [2]
4.5 It remains active inside language
Speech in ordinary interaction is accompanied by mouth movement, prosody, gaze and co-speech gesture. Remove the body and the channel loses information about emphasis, reference, stance and timing. [3]
4.6 It supports communication without speech
Noise, distance, hunting, secrecy, disability and social convention can make bodily channels preferable. Silent gestures can coordinate action where speech would expose, interrupt or endanger participants.