Buzz
There’s a popular belief that rubbing an alligator's belly can render it powerless. While some may not think about the challenge of getting close to such a creature (keeping in mind how near its stomach is to those sharp teeth), we're here to confirm this is actually true—and alligators aren’t the only animals known for this reaction.
"Belly rubbing is known as tonic immobility," explained Sean Henderson from the National Zoo to The Washington Post in 2008. "It’s a state of hypnosis triggered by flipping the animal onto its back and fully extending its neck," which, as we noted, happens when you stroke its belly. Henderson cautioned, though: "Tonic immobility typically occurs when the animal is under extreme stress. Don’t attempt this yourself!"
In Isaac Marks’s Fears, Phobias and Rituals: Panic, Anxiety, and Their Disorders, tonic immobility is described as the “extended stillness and reduced responsiveness in an animal that was once active, in response to a perceived threat.” This state can last anywhere from 15 seconds to several hours, but on average, it lasts about eight to 10 minutes in chickens. (Yes, they can experience it too!)
Sharks, too, are creatures that can experience tonic immobility. There appear to be two main methods for inducing this response in sharks, with rubbing their nose being the most effective. While the exact cause remains unclear, one ecologist suggests that “[an] untested possibility is that a shark’s electroreceptors are concentrated in the snout area, and perhaps overstimulating this area ‘shocks’ them into immobility.”
Another method of immobilizing a shark is to flip it onto its back. WIRED described an unusual instance where a shark was put into tonic immobility by another animal:
“In 1997, witnesses observed a female orca off the coast of California seemingly induce tonic immobility in a great white shark on purpose. The orca kept the shark upside down, triggering tonic immobility, and held it still for 15 minutes, which led to the shark suffocating to death.”
Remember when we mentioned that tonic immobility affects chickens as well? WIRED suggests that it might be a defense mechanism for the birds. “You can lay it on its side, tuck its head under its wing and gently rock it, or place it on its back and stroke its sternum,” the article explains. “You can wave your finger in front of its face—starting near its beak and slowly pulling it back. The chicken will focus on your finger.”
Tonic immobility impacts different animals in various ways. “I’ve seen alpacas and llamas ‘calmed’ into a relaxed state by softly rubbing the upper gum just beneath the cleft in the upper lip,” veterinary surgeon David Anderson shared with the Cincinnati Enquirer. “The animals stop resisting being held and cease vocalizing.”
