A person cannot live without a head, but what about cockroaches? It turns out that this is a common thing for them, and they are able to exist in this state for quite a long time - up to several weeks. Why so - explains the physiologist and biochemist Joseph Kunkel from the University of Massachusetts at Amherst (USA).
According to him, cockroaches do not have such powerful blood pressure as humans. “They don’t have a huge network of blood vessels or tiny capillaries that need to maintain high pressure for circulation,” Kunkel said.
Once a cockroach is decapitated, it doesn't bleed to death (as a human would), instead the wound simply folds over.
But what about breathing?
Cockroaches breathe through spirals or small holes in each segment of their body. The brain does not control this breathing, and the blood does not carry oxygen throughout the body. Instead, the coils direct air directly to the tissues through a set of tubes called windpipes.
What about food?
Cockroaches are cold-blooded, meaning they need much less food than humans. “After eating once, an insect can live for several weeks. A headless cockroach will just sit quietly until it becomes infected with fungi, bacteria, or a virus. Then he will die,” the scientist explained.
Does the head live its own life at this time?
Not only the body of a cockroach can survive decapitation - the head also remains alive and is able to wave its whiskers for several more hours.
Read more:
It is quite difficult to answer the question of how long domestic cockroaches live. It depends on many factors. There are legends about this type of insects that they are able to live for several years, and sometimes even without food, water and a head. Some of these judgments remain true, but it is worthwhile to understand in more detail the features of such survivability of the Prussians.
Separately, it must be said that they demonstrate a higher resistance to radiation compared to humans. Withstand radiation 15 times more intense than the fatal dose for humans. Similar characteristics of insects determine their adaptability to different living conditions, which is why it is not so simple.
Total life span
One of the most interesting questions is how long cockroaches live. To answer it, you need to familiarize yourself with the growth characteristics of these pests. All representatives of these insects have an incomplete development cycle. This means that a larva (nymph) hatches from an egg, which, after a series of molts, becomes a full-fledged adult (imago). However, how long does it take from the moment of hatching to the physiological death of the Prusak?
Conventionally, the entire life cycle that red, black or any other types of cockroaches go through can be represented in the following sequence of events:
- After laying eggs in the ootheca (the capsule where the female stores them) and until it swells, an average of 4-5 weeks pass.
- Then the female drops the ootheca in some secluded place, where after a couple of days small (up to 3 mm) larvae hatch from it.
- Nymphs already lead an almost normal lifestyle for cockroaches at home, with the exception of the breeding function.
- After a certain number of molts, the larvae mature and turn into adults (adults). At a temperature of 30 ° C and above, this process in red cockroaches takes about 2 months. With thermometer readings in the range of 22-25 ° C, the time increases to six months.
The average life expectancy of the average red Prussian, which is most often found in people's homes, is 9-10 months. At the same time, it is sexually mature for 20-30 weeks, which allows you to very quickly increase the size of the pest population. An important role here is played by the high fecundity of female insects.
Some species may exist for a longer period. So Madagascar cockroaches live for almost two years. A representative of a black insect, which often bothers people, can exist for about 1.5 years.
How long do cockroaches go without food and water?
Given that cockroaches are cold-blooded creatures, they can go without food for quite a long time. Cockroaches do not expend energy to maintain a stable body temperature, which allows them to eat very rarely.
One standard meal for insects can be enough for 40-70 days (depending on the type of pest). A slow metabolism contributes to a very slow expenditure of energy reserves, which does not allow hunger to develop quickly. However, despite this, quite a lot remains.
If we talk about water, then the situation is a little different. For any organism, moisture is the source of life. The Prussians are no exception. They need water for digestion, the functioning of the circulatory system, respiration and many other vital metabolic processes in the body. Without it, cockroaches die within a week. Therefore, it is worth taking care of eliminating a variety of fluid leaks from taps, flowerpots, etc.
The ability of cockroaches to live without food and water determines their highest adaptability.
How long do Prussians live without a head?
American scientists have proven that cockroaches have the ability to exist without a head. Not only that, their head can also work offline, but with a number of flaws.
The reason for such a paradoxical possibility remains the anatomy of these insects, which differs significantly from the human one.
Headless cockroaches live thanks to the following points:
- For breathing, they use small tubes that are located not on the head, but throughout the body.
- They do not need a main brain to support basic life support functions. All processes are carried out with the help of separate nerve ganglia located throughout the body.
- The circulatory system functions perfectly even without a head.
The only limitation that sets the time for how long a cockroach lives without a head is the absence of a mouth apparatus with the ability to absorb food. Therefore, in this state, the Prussians can withstand up to 40 days of existence.
One way or another, but cockroaches remain one of the most tenacious creatures on the planet. When they appear in the house, you must immediately begin to fight them, because they are at a tremendous pace.
Find out who else can live 9 days without a head, as well as how the classic cockroach experiment went:
The entire detachment of cockroaches is considered very hardy insects, although in terms of existence without food, they easily “plug them in their belts”. But cockroaches differ in that they continue to move for a long time after decapitation. Scientists were interested in the question of how long a cockroach lives without a head.
Is life possible without a head
Why does the headless body of a cockroach function for a long time
Under a microscope, Tipping would decapitate the periplanet and seal the cuts with dental wax to keep moisture from escaping from the insect's body. He found that in sterile laboratory conditions, a cockroach can live without a head for several weeks. The word "live" here is conditional, since the body was passive and did not move much, but reacted to touch.
On a note!
In non-sterile conditions, the body lives no more than 7 days without a head, as mold fungi and bacteria “eat” it.
And the physiologist and biochemist Joseph Kunkel, who studies the development of cockroaches, had to explain why the decapitated body “lives” for many more days. Kunkel explained this phenomenon by the peculiarities of the internal. If compared with people, then a person who is decapitated dies from blood loss. But even if the blood could be stopped, people would still die. The fact is that the center that controls breathing is located in the brain in people. With decapitation, the nerves stop receiving signals to control the intercostal muscles, and the muscles stop stretching and compressing the chest. There are no muscles in the human lungs, they swell due to the expansion of the chest. As a result, when the brain dies, people suffocate, even if the head remains in its place and there was no blood loss.
Cockroaches are different. Their brain is very conditional. The insect has several nerve centers, ganglia, distributed throughout the body.
On a note!
Cockroaches are cold-blooded creatures. When cooled, all processes in their body slow down. If you keep the bodies of insects in the refrigerator, they "live" longer.
Head without cockroach
The severed head also continues to "live". She wiggles her mustache. But this part stops moving pretty quickly. She does not have the "fat reserves" of the body, so she only exists for a few hours. If you supply the head with nutrients and put it in the refrigerator, it will live longer.
Cockroaches are the most tenacious creatures on earth. It is generally accepted that they can not die for a long time without food or water sources.
And also there is an opinion that they can live for some time without a head. Entomologists can clarify and explain how long cockroaches live without a head.
How many lives without a head
How many days a cockroach can live without a head was determined by researchers from the United States. During the experiment, it was found that a cockroach without a head continues to exist for up to 9 days.
And while maintaining specific conditions, this time increases and the insect survives up to three weeks.
During the study, they established not only how long a cockroach lives without a head, but also how long a head can exist autonomously.
Can live without a head
If a person is left without a head, then in a matter of minutes he loses a critical amount of blood, his blood pressure drops, and oxygen and nutrients stop flowing to his internal organs.
However, the head of the cockroach is important in the sense that it contains the mouthparts necessary for the intake of food. But the cockroach lives without a head without any problems, since it is not necessary for him to eat daily.
In humans, respiratory acts are carried out through the nose and mouth.. And the cockroach breathes with the help of spiracles (special holes localized on the body) and small tubular elements (trachea).
At the same time, the brain is not involved in the process of breathing. After depriving the head, the insect's body continues to receive oxygen in the same quantities.
Life cycle and features
The life cycle of a cockroach is characterized by an incomplete chain of transformations. An adult cockroach does not have a pupal stage after the eggs hatch.
Features of the development of cockroaches:
- The fertilized female lays her eggs in the ootheca. It is a dense capsule located on the abdomen. After a while, the ootheca becomes dark and begins to increase in size against the background of eggs growing inside.
- After 14-28 days, the female drops the capsule in a damp, hard-to-reach place. Nymphs appear there (miniature cockroaches up to 3 mm in size). Some types of Prussians do not shed the ootheca, but wear it on themselves until the very appearance of offspring.
- The nymph transforms into an adult, passing through 6-10 molts. As the nymph grows older, the chitinous cover of the nymph darkens and hardens. In the hot season, this process takes up to 2 months, in the cold - up to 6 months.
Most commonly found in homes, the Prussian can have a lifespan of 5 months to a year.
In the absence of favorable conditions for existence (limited access to water or food), the life span of a cockroach decreases several times.
Video
Cockroaches live even without a head
How many live in different conditions
The body of pests is distinguished by a special endurance. Entomologists have been studying these insects for years and know exactly how long a cockroach will live without a head.
They also explain how long these pests live in other extreme conditions.
Water requirement
Cold-blooded insects can live longer without food. Water is essential for the functioning of any living organism. Water is the main element of the cell cytoplasm.
Pests feed mainly on wet waste. Without liquid, the normal functioning of the salivary glands and the normal digestion of food are impossible.
It also disrupts blood circulation. These insects conserve water at extreme temperatures and low humidity due to the fact that they have water-impervious covers of chitin.
Can it live without food
Cockroaches are able to starve for quite a long time. Domestic Prussians go without food for up to 40 days, and black individuals for more than 60 days.
The body temperature of these living creatures varies widely, adjusting to the surrounding temperature regime. They do not use energy to maintain their own temperature.
Their metabolic processes are much slower than in animals with a constant body temperature.
After one meal, the Prussian can live up to 15 days without feeling hungry. But since cold-blooded animals receive energy from external sources, they prefer to live in warm living quarters with high humidity.
Can survive without oxygen
Biologists have identified the ability of cockroaches to hold their breath for 40 minutes or more. They stop breathing if carbon dioxide levels rise too high.
And also cockroaches react sharply to too high an oxygen content.. To protect their internal organs, they temporarily stop breathing.
Entomologists have an assumption that cockroaches hold their breath in order to retain moisture, which is dynamically consumed during this process.
This is a useful adaptation mechanism. In practice, cockroaches live longer without a head than without oxygen.
Temperature regime
These insects love moderate temperatures. At -5 °C insects die in half an hour. At -10 °C, mature individuals and eggs die after 2 minutes.
However, excessively high temperatures can also significantly reduce the pest population. At +50 °C, which persists for 1-2 hours, the insect also dies.
Harm from cockroaches
Cockroaches are capable of causing such harm:
Such insects are especially dangerous in schools or kindergartens. There they may well become the culprits of the mass spread of infections.
If insects are regularly found in a children's educational institution, then it makes sense to urgently invite insecticidal services.
Known for their survivability, cockroaches are often spoken of as being capable of surviving a nuclear war. Some even claim that these arthropods can exist without a head. Turns out, it's a real fact: sometimes a headless cockroach lives for weeks.
"In order to understand why insects can survive after decapitation (decapitation), it is necessary to understand why this does not happen in humans," says physiologist and biochemist Joseph Kunkel of the University of Massachusetts Amherst.
Decapitation in humans leads to loss of blood and a drop in blood pressure, which in turn disrupts the delivery of oxygen and nutrients to vital organs. In addition, a person breathes through the mouth or nose, and this vital function is controlled by the brain, respectively, after decapitation, breathing stops.
In order for blood to pass through the vast network of human blood vessels, especially through the thinnest capillaries, it is necessary to maintain pressure at a certain level. In arthropods, the circulatory system is arranged differently: it is not so extensive, it lacks thin capillaries, which allows the pressure to be significantly lower.
“When you cut off a cockroach’s head, the blood vessels in the neck are clogged with clotted blood,” Kunkel notes, “and no fatal bleeding occurs.”
What's more, these tenacious creatures breathe through spiracles - small openings on each segment of the body. The brain of a cockroach does not control breathing, and oxygen is carried throughout the body by blood; air enters the tissues directly from the spiracles through the tubes (tracheae).
In addition, cockroaches are poikilothermic creatures, that is, cold-blooded. Consequently, they do not expend energy on maintaining a constant body temperature, and therefore can be content with much less food than humans. Having eaten once, they are able to live for weeks after that.
“Unless they are attacked by some kind of predator, they will just sit quietly and motionless,” says Kunkel.
Cockroaches have ganglia in each segment of the body - accumulations of nervous tissue capable of performing basic reflex nerve functions. Even without a brain, the body of an insect can function at the level of simple reactions. It can stand up, respond to touch and move.
A lone head can also continue to function and move its whiskers for several more hours. If you cool it, it will last even longer.
Decapitating a cockroach may seem like a creepy task to some, but researchers have conducted many experiments with the bodies of these insects to answer a number of serious questions. Decapitation deprives the arthropod's body of the hormones that control maturation and are secreted from the glands located in their heads. This discovery allows scientists to study metamorphosis and reproduction in insects, and also reveals how neurons work.
