I remember some long-ago TV programme about some aspects of social anthropology touching on this. They said, I think, that dancing was important for social bonding because it entailed synchronised moving to music, and also because, in many cases, it also involves physical contact between the dancers.

In many societies, when people are elated and celebrating, (e.g they've just heard some great news), their spontaneous reaction will be to join hands and dance in a ring, clockwise, possibly singing or chanting something together. Ceilidh dancing includes some moves that are quite primal and instinctive for humans - and many, it has to be said, which are not quite instinctive enough for some of us :-)

Marje