A t dusk in the east Texas town of Montgomery, the pale golden sky gives way to striations of pink and plum light. In the distance, on the Cartwright farm, cows converse in low baritones. From somewhere farther away on this 246-acre spread comes a surprising sound: a gentle, jazzy timbre, resonating like a bass. Music, yes, but not exactly strings. It's the love call of the high-stepping emu (pronounced ee-myoo), a large, flightless bird that is appearing with increasing frequency on farms and ranches not only in the United States, but around the world. Duncan and Bitsy Cartwright have raised emus since 1989, when they first saw this odd bird at the Houston Livestock Show. Today, they have 33 breeder pairs and over 200 chicks. "I got interested in agricultural diversification," says Duncan. "Products of the bird have a lot of potential. And agriculture needs all the entities it can to be profitable." As Duncan points out, birds can be raised on a fraction of the land required for cattle or hogs. His entire emu flock exists happily on 4 acres. The emu belongs to an order of birds known as ratites (Strunthioniformes), which are characterized by their lack of a keel on the breastbone. There are four suborders of ratites: rheas, ostriches, cassowaries and emus, and kiwis. Earth-bound and top-heavy, these birds look like primordial turkeys: tiny heads, big bodies, and skinny legs. Indeed, the ostrich has its origins in the Eocene epoch, about 55 million years ago.