Sometimes people in non-Western cultures simply drill holes in a flute to match the hand of the person it's going to be made for. i.e, where do their fingers fall? that's where I'll drill the holes! So every flute was different.

Works fine with percussion or with other instruments as long as they are far enough apart in pitch.

Reminds me of a piece I was heard by Villa Lobos - flute at the top of its range vs cello. No wonder he was able to write 2,000 pieces. The instruments were so far apart there was no need to worry about harmony.