Lobsters lack the brain anatomy needed to feel pain, said Dr. Ayers, who builds robots modeled on lobster and sea lamprey neurobiology. Lobsters and other crustaceans are often swallowed whole by their prey, he added, so they never needed to evolve the ability to detect pain from say, warming water or an electric shock.
Michael Tlusty, a lobster biologist at the University of Massachusetts Boston, takes a middle ground. He agrees that lobsters lack the brain anatomy that we associate with pain sensation. But crustacean brains are so different from ours, he said, that no one can really say for certain what they are feeling.
For instance, when a lobster’s claw is being attacked, it will jettison its own arm to escape. “When a human does that, we make a movie about it,” Dr. Tlusty said, referring to the 2010 survival drama “127 Hours.”
Lobsters continue to twitch after they’ve had their limbs ripped off, he noted, but it’s unclear whether that’s in response to unpleasant sensations or a programmed reflex — like your leg kicking when a doctor taps your knee in a particular place.
Dr. Elwood got the idea for researching lobster pain about a dozen years ago at his local pub. Celebrity chef Rick Stein, known for his seafood dishes, was having a pint, and Dr. Elwood introduced himself. The chef stumped him by asking if lobsters felt pain when cooked.
In several studies since, Dr. Elwood has shown that crustaceans guard wounded limbs and avoid areas where they’ve been shocked — even leaving their shells behind if necessary. When he traveled to Singapore, he said he watched as street sellers kept grabbing live crabs as they scuttled off a barbecue grill, keen to get away.
He’s now convinced that those responses are the crustacean equivalent of pain. As David Foster Wallace observed in his famous article “Consider the Lobster,” lobsters remain the only animals we still kill in our own kitchens. We have to face the ethics of that decision, he noted, while we more easily ignore such feelings about other animals in our diet.
Boiling might take as long as a minute to kill a lobster, long enough for it to suffer, Dr. Elwood said. A skilled chef who slices right into a lobster’s head should be able to kill the animal faster, he said. “That should be a reasonable way of doing it.”
He also mentioned a commercial device called a Crustastun that zaps the animal with electricity, promising to kill it instantly. The Swiss government cited electrocution as a preferred method of killing, though the Crustastun, which reportedly costs $3,400, is meant to be used by processors or large restaurants.
Dr. Ayers dismissed the method, saying he’s seen animals moving for minutes after being stunned. He said he loves lobsters as much as anyone — he’s devoted his career to studying them, and his son is a lobster fisherman — but he said he doesn’t see a more humane way of killing lobsters than dunking them headfirst into a pot of boiling water.
Dr. Tlusty has an alternative strategy: He puts lobsters on ice to slow their nervous system before they meet the pot.