The art of origami has a well-known cast of characters—frogs, crabs, rabbits, and, of course, the queen of the repertoire, cranes. But add a physicist to the mix, one Robert J. Lang, and suddenly the art is elevated to … art. Lang’s approach to origami has a mathematical foundation (which must be how, from one piece of paper, he was able to fashion the long antennae and even longer legs of his Katydid HP, Opus 629). And yet the only science visible in the creatures he creates is that of the naturalist, the keen eye for both silhouette and behavioral posture that comes with years of looking. Running concurrently with “FaunaFold” is an exhibition of origami-oriented sculpture, “Alchemy Unfolding,” in which form emerges from a sheet of metal instead of paper. The ingenuity is amazing. —L.J.