Gulp: Adventures on the Alimentary Canal



The superworm is extracted and set aside. Like the others, it is motionless but not dead. And as with all the earlier entrées, this one will wake up after half an hour or so outside the stomach and appear to be fully recovered. A second worm is left in place overnight, to rule out the possibility that superworms can shrug off the blanket effect and resume their efforts to escape. It is dead by morning. “There is no way in my mind that they can eat their way out of stomachs,” states Tracy.

Walt is not as sure. He was impressed by the vigor of the superworm’s struggle. “What if there were a weak spot in the stomach?” Might it be possible to escape a stomach by rupturing it with an especially forceful squirm?

That appears to be what was depicted in a photograph that went viral in 2005, of a dead python in a Florida swamp with the tail and hind legs of an alligator sticking out of its side.

“That’s what everyone was saying: that the alligator kicked its way out,” Stephen Secor told me. Secor had been flown out to the scene by a National Geographic television production team, who had hired him as an on-camera expert for a one-hour special spawned by the chimerical remains. Secor knew before he arrived that the dinner-kicking-its-way-out scenario was extremely unlikely. Pythons kill their prey before eating it.* “And there’s no way stuff can move once it’s inside there.”

There was in fact a weak spot. Secor pointed to a printout of the photograph I’d brought with me when I visited his lab in late 2010. Two-thirds of the way down the python’s exterior is a patch of black (dead) tissue—a poorly healed wound from some earlier incident. The rupture of this wound, Secor thinks, was caused by an alligator, let’s call him alligator B, who attacked the python while he was digesting alligator A. The python broke open at the poorly healed wound, and A popped out. So it wasn’t, at the end of the day, a case of dinner exacting revenge from within. Just another dog-eat-dog day in the Everglades.

THE OTHER THEORY Stephen Secor debunked for the National Geographic program was that the alligator dinner was so enormous the python simply burst. “That,” he said, pointing to the meal in the famous photograph, “is nothing.” The python is built to accommodate prey many times wider and bulkier than itself. The esophagus is a thin, pink stretchable membrane, a biological bubble gum. Secor went over to his computer and pulled up a slide of a python engulfing the head, neck, and shoulders of an adult kangaroo. This was followed by a shot of a python with three-quarters of a gazelle “down in,” with only the hips and rear legs remaining al fresco. Pythons use their muscular coils to pull the prey apart, like taffy, so it’s narrower and easier to get down. And they don’t swallow in a single peristaltic wave of muscle contraction, as we do. They do what’s called a “ptergoid walk.” They inch their jaws along on the prey like marines on their bellies, moving forward by the elbows, left, right, left.

The other reason Secor could dismiss the bursting-stomach theory is that he knows exactly how much pressure that would take. “We sealed off the cloaca of a dead python and inserted an air line down the esophagus.” Probably much like you at this moment, Secor was “sick of listening to people talk about pythons bursting.” I would give you the citation for his experiment, but Secor did not publish a paper. It was “just a fun thing.” He pointed to my printout of the python-alligator photo. “It was a lot more pressure than could be generated from this.”

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