Watch the vocal chords of singers while they sing video
Geege Schuman stashed this in Anatomy
It's pretty alien looking, looks like a beak, maybe that's what it evolved from? Amazing that such a rudimentary looking thing can make such a precise and beautiful sound.
Nope, it evolved post-ape less than 100k years ago:
They do look like baby birds though. Can't get that image out of my head.