If you liked The African Queen, make a bee-line to Washington, D.C.’s Smithsonian Institution. It’s offering a spectacular view of those mysterious, ecologically fragile spaces where half the world’s plant and animal species live. The show’s vivid dioramas carry a message. The forests where the musician wren sings and the bromeliad flower blooms are in danger. We lose nearly an acre of rain forest every second to farmers, loggers and ranchers. At the Smithsonian until Jan. 2, the show then goes on tour.