The current economic climate makes it nearly impossible for jazz big bands to tour -- especially those that offer new music instead of nostalgia. So it is welcome news indeed that District Curators and the Smithsonian Resident Associates are cosponsoring a two-year series of avant-garde jazz big-band concerts. That series got off to an auspicious start last night as the legendary but rarely seen composer George Russell brought his 14-piece Living Time Orchestra to the Museum of Natural History. Not only were the harmonics, melodic and dynamic shifts in the extended suites often astonishing, but the rollicking, joyful rhythms often tempted one to flout the Smithsonian's decorum and get up in the aisles to dance.

Like many big-band leaders, Russell, 63, plays piano, but he is also an ex-drummer, and he built his pieces up from the foundation of Stan Getz's drummer Keith Copeland and Boston Symphony percussionist Pat Hollenbeck. The ensemble's four electric instruments (bass, guitar and two keyboards) were usually given a muscular and deliberate rock motif, which lent the band a fat, insistent bottom. Over this bottom the eight horns played free-jazz solos, Ellingtonian harmonies and counterpoint modal figures. There was often so much going on at once that one's attention darted eagerly here and there about the stage.

The program reached back to 1947 for Russell's landmark collaboration with Dizzy Gillespie, "Cubano Be, Cubano Bop," which featured a taped performance by the late percussionist Sabu Martinez. "Electronic Sonata for Souls Loved by Nature," Russell's 1968 tribute to New York, evoked the city's energy and tensions in the competing horn parts and the very funky rhythms. The evening's highlight, though, was the 40-minute 1983 suite "The African Game," a stunning example of Russell's theory of "vertical form." The central rhythmic motif didn't so much change as it was complicated by layer upon layer of ever-shifting variations on the same pulse.