Here Mucyo guides some Morrocans on a dance tutorial for Rwandan dance. I have been informed by a reliable source that the wide open arms are meant to imitate the horns of a cow. The graceful movement from side to side is also based on the movement of a cow. You can also not the rythmic drumming because that's what the dance follows 1,2,3,4 and 1 again.

If you're interested the instructor (the one with the Afro) has an instagram page. mucyowicyogere_333 with the username Mucyo w' Icyogere.

In case the video isn't playing properly here is the direct link to the post on instagram.