http://www.nytimes.com/2009/05LISA ROSS: UNREVEALED, through June 13. That installation art of an extraordinary sort is as old as humankind receives further buttressing from large color photographs documenting holy sites in the Xinjiang Uyghur region in northwest China. In desert terrain, indigenous Muslims mark the graves of their dead with tangles of tall sticks and flags. Modest graves can be just a few sticks and a flag or two. Religious leaders, who are often viewed as saints, merit relatively large, shrine-like masses that are as high as 60 feet. Either way, the structures spirituality is self-evident. A video whose only sound is the flags flapping in the wind further explains their power. Daneyal Mahmood Gallery, 511 West 25th Street, (212) 675-2966, daneyalmahmood.com. (Smith)