Art rarely mashes up genres as disparate as modern dance, baroque opera and Roman epics. Yet the Mark Morris Dance Group has been pulling off the combo since 1989.  For their modern dance version of Purcell’s opera, “Dido and Aeneas,” at Northrop on Wednesday, the 12 dancers are collaborating with a live orchestra, chorus and solo vocalists.

“It’s one of the great pieces of music in the Western canon and [one of the first operas] in the English language,” said Morris. In addition to leading his eponymous group, he’s the piece’s choreographer and the orchestra’s conductor.