Breath catches before sound does. Across dry grass, a cheetah's rib cage pumps while its paws turn a chase into a blur; the animal can hiss, yelp, chirp, and purr, but the full-throated roar of lions and tigers is absent. That absence is not a missing feature. It is part of the machine. Body mass does not grant the roar; the vocal tract does.Roaring is specialized hardware. In lions and tigers, a ...More