Gulp: Adventures on the Alimentary Canal

For me the confusion can be traced to the movie Anaconda, the scene in which the giant snake rises from the water to regurgitate Jon Voight’s character, his face melted like wax. Some time back, I visited the lab of my favorite snake digestion expert Stephen Secor, the technical consultant on Anaconda. I told him I wanted to experience gastric acid, to get a sense of what it might feel like to be alive inside a stomach. He made me promise not to tell his wife, who oversees safety protocol for the university’s labs, and then he took a bottle of hydrochloric acid off a shelf and put a dab—five microliters—on my wrist. I braced for sharp heat, as from a drop of scalding water. It was a full minute before I felt anything at all, and then only a weak itch. He added another drop. At three minutes, the itch turned to mild irritation, which held more or less steady for twenty minutes, then faded to nothing. It left no mark.

But stomachs secrete more than a single drop of hydrochloric acid. And they keep on secreting, readjusting the pH as the digesting food buffers the acid. My guess is that the situation inside an actively secreting stomach lies somewhere between what occurred on my wrist and what happened to the Japanese factory worker who fell into a tank of hydrochloric acid seven feet deep. The case report states that his skin turned brown and the delicate tissue of his lungs and digestive organs underwent “dry coagulation necrosis.” Burning—whether from acid or from heat—denatures proteins. It changes their structure. It is denaturing that solidifies the boiling egg, that curdles milk, that distorts the burn victim’s skin. Inside a stomach, hydrochloric acid denatures edible proteins, making them easier for digestive enzymes to break down.

The effects of gastric acid are insidious but far from instantaneous, especially if the eaten entity is, like a superworm, protected by an exoskeleton. Crabs vomited after three hours in the stomach of the Asian crab-eating snake Fordonia leucobalia have been known to stand up and run away. I have an eyewitness for this: University of Cincinnati biologist Bruce Jayne. Jayne had “gently massaged” the snakes’ bellies to get them to surrender what they’d eaten, so he could tally it for his research. Because you can’t just ask them.

But without Bruce Jayne to massage the belly, without Lee Lemenager to pull the surgical thread, without God making the whale regurgitate, there would seem to be no way out.

Parasites are the exception. “Parasites bore all over the place,” says Professor Tracy. Some are equipped with a boring tooth, like a drill bit installed on the top of the head. “That’s what they’ve evolved to do. But these are mealworms, for crying out loud.” Larvae burrow, but they don’t bore. “How the hell would they know to tunnel out?” Walt the vet agrees. He is off and running with a story about the giant kidney worm, a parasite that bores out the entire organ and then exits the body through the urethra. He jerks his elbow toward the endoscope. “You could watch it coming with that scope.”

TRACY IS GOING to give the superworms one last chance, the best possible chance, to see if they can chew their way to freedom. They will be put inside a dead stomach—one with no secretions and no muscle contractions.

Where do you find a stomach on a Thursday afternoon in Reno?

“Chinatown?” suggests someone.

“Costco?”

“Butcher Boys.” Tracy pulls his phone from a pocket. “Hello, I’m from the university”—the catchall preamble for unorthodox inquiries. “I’m wondering, is there any chance at all we could get a fish stomach from you?” Tracy waits while the man goes to ask someone and/or make twirling finger motions at his temple for the benefit of his coworkers. The lab falls quiet. The feeder crickets chirp in the next room. “No stomachs of anything? No. Okay.”

John Gray lifts his head and says, in his quiet way, “I’ve got a dead leopard frog in the freezer.”

Everyone takes a break while Gray goes to defrost his frog under a warm tap. Walt entertains us with talk of an alternative-medicine experiment going on at the medical school—healers practicing Reiki on mice. Tracy walks next door to get a toad to show me, a new species he discovered doing fieldwork in Argentina. He returns with it in a glass dish, cradled against his belly. He looks like a kid standing in the kitchen with his cereal bowl. It’s a nice toad, less warty than some. I tell him this, and he seems pleased. “You could be the first person to like this species.” Second, I’m pretty sure.

“You could be the last too,” says Lee, more of a frog guy.

Gray rejoins the group with the defrosted leopard frog, now pinned in a dissecting tray. Lee snips up the midline of the belly and peels back the flaps of skin as if they were stage curtains. Professor Tracy slides a superworm into the stomach.

The 1925 essay “The Psychology of Animals Swallowed Alive” opens with the author sitting “in quiet contemplation digesting after dinner” and wondering whether animals that swallow their prey live* are “worried by the acrobatic effects of victims trying to escape.” If this leopard frog were alive, if frogs have the neurological wherewithal to worry, then the answer must be yes, they sometimes worry. The mealworm, with obvious worries of its own, animates the frog stomach like a sock puppet, arcing and straightening and squirming in the snug pink sac for fifty-five seconds. Then it stops completely. “Blanket effect,” says someone.

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