The Dancers are Apache Spirit Dancers. If you search on Bing you get lots of hits, including very modern ones. Apparently the dances survive in the annual festival in Gallup NM.
Here is a url with several more pictures.
http://www.worldfpa.org/poto.asp?id=88
I haven’t been able to find what the spirit dances represent but it seems clear the costumes are depicted on the petroglyphs found all over the southwest. The question is...... did the Apache develop a cult from seeing the petroglyphs? or have the costumes been in use for 11,000 years when the article says the petroglyphs were rendered?
This is information I’ve waited years for...and then the concept they were influenced by the drawings and develop a cult from it, aack! Archaeolgist/anthropologist nightmare.
Darn I want to know the answer to these things.