Was the first musical instrument, a bone with holes in it i.e. a recorder? Or perhaps beating 1 or 2 bones/sticks on a suitable surface? But not currently for a chimpanzee, since a lack of rhythm for any such activity. Hence the requirement of rhythm to convert noise making to musical sound.
Would chanting (with a nascent sense of rhythm) seem more primitive than commencement of language sounds?
Might a developing rhythmic sign language, enhanced selection for fine motor control, and hence cerebellar development, go hand in hand?
Would a distant journey be easier with a rhythmic cadence, as now?
Was our species’ upside breakout (i.e. dominant population expansion) ~200,000 years ago, related to selection for cerebellar development i.e. new connections?
Hence might rhythm, and accompanying cerebellar brain connections, development, and/or their takeover, be required for initiation of music and language? Thus was the road to music and language a rhythmic one – a stable evolutionary strategy, relating more to cerebellum than just neocortex development?