I just learned that a common cockroach can live for approximately 9 days without its head before it will die.?

Question

Why doesn't it die right away and why does it take so long to die?

Answer 1

The first thing you need to do is define is what "death" is. Normally when we talk about death we mean brain death. When you chop a cockroach's head off it is brain dead within minutes. The body will continue to survive for several days but the cockroach itself is very dead.

As for why the body survives so long, it's really twofold.

First off insects don't have blood like we do. When you chop a human's head off all the blood runs out of the cut. The body needs blood to supply its oxygen and nutrients so the blood loss associated with decapitation kills the body. Insects don't have blood or blood vessels like we do, so when you chop the head off they lose very little fluid. That removes one of the primary causes of death.


Secondly a cockroach's brain is really only used to process sensory information, it isn't used to keep the body going. When humans get their heads chopped off the body dies almost immediately because the brain is controlling most of the functions that keep the body going. The human brain controls breathing, it controls temperature regulation, it even controls our ability to stand upright. Without a brain the body stops breathing and suffocates, and if that didn't happen we would either freeze or cook.

Cockroaches don't breathe and being cold blooded they don't have any real temperature control system so they can't die from those things. Even the ability to balance and walk isn't controlled by the brain in cockroaches. Those things are controlled by the the insect equivalent of the spine.

So al that a cockroach really loses when the head is removed is the ability to process information from the eyes and antennae. Since those things aren't crucial for survival their is no reason for the body to die. After a few days the inability to drink, combined with fluid loss from the wound, will result in death.

Answer 2

Because they have an ever changing molecular structure. The body of a cockroach can adapt to just about any poison you throw at it and it is designed to protect itself with its outside shell. When a head is cut off of the cockroach just like the human body. The body doesn't know it is dead yet because it goes into shock. So usually our bodies tend to receive the message faster than there's do.

Answer 3

Because its anatomy is like many insects in such a way that their head is not as important as a human's. With us, removing the head would disconnect our brain from our body and our circulatory system would be severed.

A roach does not have these, and instead has a very primative form of a nervous system (with no brain). So, the body is able to stay alive on its own because the head contains nothing of real use to survive except a mouth... which it eventually dies in 9 days because it cannot eat.

Answer 4

May be, as the heart is functioning it lives. It should have died due to the lack of food, but this character cockroach is immune to all chemicals and is very difficult to kill it. Even when Japan was bombed during the World War ,they survived that attack. They also multiple in very large numbers and survive in all filths.

Answer 5

Every creature is unique and have different ability and talent.Not only that the cockroach will live even wothout a head but also it can withstand extreme radiation.

Answer 6

who cares why it can live without its head. If you ever incounter one squish the guts out of the body and you wont have to worry about it living even 9 seconds longer.

Answer 7

because they can fly and we all know that anything that can fly can definitely live without a head

Answer 8

I tried spraying zonrox, and they can't live a minute.

Answer 9

i think it's just 1 week

Answer 10

No one seems to know, but it's scary