Stuffed snake.

After eating a big meal, you might feel too stuffed to move. That's what happened to this 18-foot-long snake found on a road in Kampung Jabor, Malaysia.

The reticulated python managed to swallow a pregnant sheep--whole! The snake was so full that it couldn't slither off the busy road, so firefighters had to haul it away.

Normally, pythons don't go after such big prey. They hunt for birds or small, cat-size mammals.

But when the snakes are extra hungry they may eat larger animals, including deer or even humans.

To locate its victim, a python uses its sense of smell and another special ability: heat sensing. Holes in the snake's jaws--called pits--house nerves that enable the snake to sense infrared body-heat, says Bill Holmstrom, a reptile scientist at the Bronx Zoo in New York.

After a python targets its kill, the snake lunges at its victim, biting the prey with as many of its approximately 80 curved teeth as it can. With its prey still in its toothy grasp, the snake constricts, or coils around its meal. Then it squeezes its victim's body until the animal stops breathing.

But how does a slim snake fit a big animal like a sheep into its mouth? Flexible rubber-band-like ligaments connect its jawbones together. By stretching these ligaments, the python can open its mouth wide enough to swallow animals bigger than itself. Then, it uses its curved teeth like a shovel to push the animal down its throat. The python moves its powerful body muscles in a wavelike motion to guide the food down into its stomach.

It can take weeks for a snake's digestive fluids to break down something as large as a sheep. But "it looks like [this] python is regurgitating its meal," says Holmstrom. "They tend to do that when they are under stress and they have just eaten." Too bad, says Holmstrom: The sheep would have provided the snake with enough nourishment for a full year.