The Cuban-born, New York-based percussionist and singer Orlando "Puntilla" Rios--known for his virtuosic work with jazzy Latin pop stars like Celia Cruz, Tito Puente, and Eddie Palmieri--comes to town with an unelectrified presentation on the folkloric roots of Afro-Cuban music and dance. The rituals and songs in this show can be traced to a time of cultural upheaval in the Caribbean, when west African lucumi pantheism blended with 16th-century Spanish Christianity to produce a syncretic religion, santeria, that placed the Yoruba orishas, or deities, in a one-to-one correspondence with Christian saints. As the costumed dancers in this program flamboyantly portray the various orishas, Rios and his crew slam up the music essential to santeria rituals; the drumming is as richly polyrhythmic as anything you've ever heard, and the singers bring their voices together at distinctively Afro-Cuban, gorgeously odd (to Western ears, at least) harmonic intervals. This. eerie, sensual music sings eloquently of the unseen supematural while simultaneously embracing a frankly hot physicality--which is just what you'd expect from a culture that organically integrates the holy and the sexy instead of forcibly dividing them. Santeria--still widely practiced in Cuba and Puerto Rico as well as in Chicago and other U.S. cities--has as its secular concomitant rumba, a music-dance form often used as a vehicle for political and social commentary; it's also featured on this program. Field Museum of Natural History, James Simpson Theater, Roosevelt and Lake Shore, 322-8854. Saturday, March 5, 1 PM. $10 (includes museum admission).