The Battle of the Bulge
by Kathleen M. Wong on July 01, 2008
A kingsnake eating a gopher snake.
Photo by Alf J. Fengler.
Snakes are famous for the amount of food they can stuff inside their skinny bodies. It’s common for a snake digesting a mouse or other prey to have an unsightly bulge marking the location of the meal. A snake’s lack of a sternum allows its stomach to expand as far as muscle and skin will stretch.
Even so, that doesn’t explain how a snake-eating snake can squeeze in prey longer than its own stomach. To observe this feat, researchers took X-rays of kingsnakes in the act of swallowing corn snakes. They discovered that the swallower uses a combination of jaw ratcheting and body movements to compact the body of the swallowee into a series of bends. Meanwhile, the stomach and esophagus stretch toward the cloaca, or anal opening. Within two weeks, all traces of the hapless corn snake will vanish.