A new study shows that crustaceans – lobsters, crabs, shrimp and prawns – do indeed feel pain. Even more, their nervous system remembers the painful experience and try to avoid a repeat in the future.
In the famous lobster scene in the Woody Allen movie, Annie Hall, lobsters scuttle all over the kitchen floor as Annie screams, “I can’t throw a living thing in boiling water.” Audience members laugh because they can relate. Most people who enjoy eating lobster have wondered at some point if their dinner suffered as it was boiled alive in the kettle.
Now a new study shows that crustaceans do indeed feel pain. Even more, they remember the painful experience and try to avoid a repeat in the future. (In case you’re fuzzy on your animal biology, the crustacean group includes crabs, lobsters, prawns, and shrimp.)
The discovery comes from research conducted on hermit crabs by Drs. Robert Elwood and Mirjam Appel at the Queens University in Belfast. The researchers sent electrical shocks to the poor crabs, and then watched and waited. Because hermit crabs live inside of host shells–they don’t carry their own–the scientists expected that stress would make them seek new shells. Sure enough, those crabs that had been shocked moved into new shells, even when their original shell provided better accommodations. Plus, as they migrated to the new shells, they demonstrated stress-related behaviors such as grooming their abdomens and banging their bellies against the empty shell. The researchers commented that the grooming behavior corresponds to mammals licking injuries in response to pain. They believe that the response indicates more than a simple reflex; rather, it shows a more complex central neuronal processing.
Dr. Elwood explains, “This research demonstrates that it is not a simple reflex but that crabs trade-off their need for a quality shell with the need to avoid the harmful stimulus…Trade-offs of this type have not been previously demonstrated in crustaceans. The results are consistent with the idea of pain being experienced by these animals.”
Dr. Elwood has a second paper coming out in which he and colleagues outline factors that make them believe that crustaceans suffer. According to that paper, crustaceans:
- Have pain receptors in their nervous system.
- Limp, rub, and show other pain-related behaviors after being hurt.
- Respond to analgesics and anesthetics with apparent relief.
- Release an adrenal-like hormone in response to pain.
- Avoid situations that caused them pain in the past and make choices based on “memory” of those experiences.
- Show signs of higher cognitive ability.
Other studies have found that contrary to popular thinking, although crustaceans can lose appendages and regenerate them, they do feel profound pain when those limbs are ripped off of them. Until these studies, scientific thinking assumed that since invertebrates lacked the neocortex found in humans, where pain registers, they didn’t experience pain as we do. But the researchers now believe that although these creatures have a different brain configuration, they certainly do feel pain.
While seafood aficionados may now have reason to feel guilty when consuming Larry the Lobster, it probably won’t do anything to help the nearly 10 million tons of crustaceans produced for human consumption annually. In fact, the research team expressed concern about the treatment of crustaceans by the research and food industries.
“There is no protection for these animals …as the presumption is that they cannot experience pain,” Dr. Elwood wrote. “Legislation to protect crustaceans has been proposed, but it is likely to cover only scientific research. With vertebrates we are asked to err on the side of caution, and I believe this is the approach to take with these crustaceans.”
If the thought of lobsters and shrimp writhing in agony (or rapping wildly on the sides of the kettle as they boil to death) gives you nightmares, you might want to switch to eating less sentient protein. Or perhaps you’re bothered by the bacteria and toxins shellfish gather from living on the ocean floor; or perhaps your concerned by the salmonella, antibiotics, bacteria, parasites, and chemical residues in farm-raised shellfish; or even by the fact that prawns and shrimp are routinely irradiated before coming to market. If not, go ahead and enjoy, but at the least, try to go for wild-caught or for organic, and don’t throw your sensitive, bottom-dwelling crustacean friends into the pot alive – at least without wearing earplugs to block out the sounds of pain.