Many chickens meet their end with a swift blow to the neck. But there’s lore that chickens can run around headless, and there were even news reports of a chicken nicknamed Miracle Mike who reportedly lived 18 months after a farmer tried — and failed — to kill it by cutting off its head.
So can chickens really survive without their heads?
The reality is that they can’t live long that way — less than a minute, experts told Live Science.
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After decapitation, chickens commonly flap their wings and move their legs, said Dr. Marcie Logsdon, a veterinarian in the Exotics and Wildlife Department at Washington State University’s Veterinary Teaching Hospital in Pullman, Washington. However, “I think the actual running around is fairly uncommon,” Logsdon said. “It’s usually just going to be strong muscle contractions of both the wings and the legs, and that’s a very common thing,” she said. Those movements typically last a minute or less, she added.
However, the answer to whether a chicken is alive or dead in the seconds following decapitation depends on how death is defined. In the case of a decapitated chicken, brain death occurs first, while cardiac death happens a few seconds later. So, in those moments after brain death and before cardiac death, one could view the chicken as either alive or dead, depending on the definition of death used.
Brain death is a state of unconsciousness in which the entire brain is permanently damaged and an individual cannot breathe on their own. Brain electrical activity in chickens stops within 30 seconds after cervical dislocation (breaking the neck), according to a 2019 study published in the journal Animals. Decapitation includes breaking the neck, so according to the framework of brain death or loss of brain activity, chickens survive a few seconds after decapitation.
“That is not to say that the animals are consciously aware of anything happening for those seconds, but there is residual electrical activity occurring,” Andrew Iwaniuk, a comparative neuroscientist at the University of Lethbridge in Alberta, Canada, who specializes in bird brains, told Live Science.
We sometimes get some jerking. That does seem to be very exaggerated in chickens.
Dr. Marcie Logsdon, veterinarian in the Exotics and Wildlife Department at Washington State University’s Veterinary Teaching Hospital
Cardiac death, which happens when the heart permanently stops beating, tends to occur a few seconds after brain death, Iwaniuk said. “The time difference would be in the order of less than 10 seconds,” he said.
As a result of these different definitions of death, Logsdon considers a chicken’s post-decapitation movements “post-mortem reflexes,” whereas Iwaniuk views the chicken as alive during those last stirrings.
Chickens move after decapitation because “there’ll be some residual neural activity in the spinal cord,” Iwaniuk said. Continued breathing is also due to residual neural activity, he said. The heart muscles, on the other hand, can continue to contract and release without neural input — until they run out of energy and oxygen, he said.
Further, the brain normally sends signals telling the muscles to relax when they aren’t needed, Logsdon said. Decapitating a chicken stops those signals, and when that happens, “we sometimes get some jerking,” Logsdon said. “That does seem to be very exaggerated in chickens.”
Miracle Mike
Something very different happened in the case of Miracle Mike. In September 1945, the BBC reported in 2015, Wisconsin farmer Lloyd Olsen decapitated a group of chickens to take to market, but one of them didn’t die. For 18 months, the rooster, who came to be known as Miracle Mike, toured the U.S. in sideshows. Olsen and his wife fed the rooster through its esophagus and cleared its airway to try to keep it from choking, but it did eventually choke to death in 1947, after the Olsens misplaced the throat-clearing syringe, the BBC reported.
This story may seem to illustrate that a chicken can live without its head. But the reality is that there’s only one widely known case of a chicken living without some of its head. Instead of beheading Mike by cutting straight across the neck, Logsdon explained, the farmer “cut off a chunk of the brain and essentially most of the face.”
Mike’s decapitation left him with the back of his brain as well as one ear, the BBC noted. He likely retained the brainstem, located at the back of the brain, which controls basic physiological functions like breathing and heart-rate regulation, Iwaniuk said. Mike probably also had his cerebellum, which helps coordinate movements, Logsdon said.
“It’s probably why he was able to actually stand up and walk, as opposed to just running around and flailing,” Logsdon said.
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