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  • They say you need a brain to get ahead, but I already have a head!

  • Hey brain dead chickens, Jules here for Dnews!

  • There’s an old urban legend that a farmer in Colorado cut the head off a chicken with

  • an axe, but instead of bleeding to death and being ground into chicken nuggets, the chicken

  • survived, headless, and just kept running around.

  • It sounds pretty crazy, but it’s just crazy enough to true, and it actually did happen

  • at least once, in 1945.

  • Not only did the chicken survive, it went on to live another, very famous, 18 months.

  • So, do chickens not actually need their heads?

  • Well, frankly, not most of it.

  • When Mike the chicken had his head lopped off, the axe missed two very vital parts:

  • the jugular vein, and the brain stem.

  • It also missed one of his ears but that wasn’t particularly important to his survival.

  • So while Mike was missing pretty much every part of his higher brain centers; the lower

  • part, which regulates things like breathing and heart rate, was still mostly intact.

  • And with a blood supply to keep it going.

  • There were some things Mike wouldn’t be able to do, like math, but since the brain

  • stem attached directly to the spine, in both chickens and humans, it could react to stimuli

  • and keep the body in homeostasis, and wellnot dead.

  • In fact, a human can technically survive without most of their brain.

  • In 2001, a boy named Trevor Judge Waltrip was born with a rare condition calledhydranencephaly”.

  • This is where the skull is filled with sacs of cerebrospinal fluid instead of the brain’s

  • cerebral hemispheres, which is the vast majority of what we think of asbrain”.

  • But despite effectively only having a brain-stem, Trevor lived to the age of 12.

  • Just like with Mike, Trevor was able to breathe, maintain a heartbeat, and respond to basic

  • stimuli.

  • And on an aside, simply not having a head doesn’t mean youre immediately dead.

  • Back when people got their heads cut off by guillotines, when France was cool, there were

  • anecdotal stories about body-less heads able to move their eyes, open their mouths as if

  • to speak, and blink for up to 30 seconds.

  • But today, scientists think that the brain really only has a few seconds after being

  • removed from the body, and thus a source blood and oxygen, before falling into a coma and

  • dying.

  • Any action after those few seconds is most likely a muscular reaction.

  • The same happens in chickens.

  • It’s not uncommon for a headless chicken, even one missing its brainstem, to run around

  • for a little while after decapitation.

  • The headless chicken’s muscles can continue to contract for a short while without a brain

  • telling them to do so.

  • And humans and chickens are not the only animals technically able to survive without a head.

  • Cockroaches can also cheat death, because theyre designed differently from us.

  • When a human or chicken heart beats, it pumps blood around the body to give it the energy

  • and oxygen it needs.

  • And one of the many things that happens when you're decapitated is you lose a lot of blood,

  • and your blood pressure drops, and your heart can’t keep up.

  • But cockroaches don’t rely on blood pressure.

  • Cockroaches and many other invertebrates have something called an open circulatory system,

  • where instead of going through blood vessels, the blood floats just around in the body cavities

  • and makes direct contact with the internal tissues and organs.

  • That means that when a cockroach is decapitated, the threat of the loss of blood pressure is

  • not that big of a deal.

  • Moreover, the roach can keep breathing with the brain entirely.

  • Roach breath comes in through holes along the body segment called called spiracles,

  • that send air to the cells that need it.

  • And because they don’t need to eat as often as humans, roaches they can survive weeks

  • without a head.

  • This gives you a living, breathing, headless cockroach.

  • Ok, I think my nightmares are set for the week.

  • No domain extension will help you tell your story like a DOT COM or DOT NET domain name.

  • And because you watch DNews, you can get 15% off Domain Dot Com’s names and web hosting

  • by using the code DNews when you check out.

  • So back to cockroaches -- why do they even exist?

  • Do they actually have a benefit to nature?

  • We have that answer right here.

  • So do you have any other general science questions?

  • Let us know down below in the comments and don't forget to like and subscribe to DNews

  • for more episodes everyday of the week.

They say you need a brain to get ahead, but I already have a head!

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B1 中級

沒有頭的雞真的能活嗎? (Can A Chicken Really Live Without A Head?)

  • 72 5
    Jack 發佈於 2021 年 01 月 14 日
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