Vocal cords... watch and listen to a movie of them working. Shit, and we're impressed when a baby sits up. What about this? Every time you make a noise! That little pink hinge, holding that thing out just so, to modulate that sound, then your tongue moving in your mouth, and your mouth itself changing shape. Wow. Constantly! Then sounds join to get words (whatever words are), and suddenly we're in the area of recombinant grammars. Oh, and air vibrations, and ears, and pattern recognition and meaning and implicature, music!, rhetoric!, and this all being refolded into genes+context. (From outside there's the babble of people talking in a restaurant, food and wine and vocal cords vibrating the tiniest, most constrained and precise sign language there ever was, the block of air in my street a shimmering, shivering foam of talking.)