No Problem: How Long a Cockroach Can Survive Without Its Head and What Contributes to This 0 17

To understand why cockroaches, like many other insects, can survive decapitation, it is worth drawing an analogy with humans. Firstly, when a human or large mammal loses its head, there is a significant loss of blood, leading to a sharp drop in blood pressure, which makes it difficult to transport oxygen and nutrients to vital organs. Additionally, breathing in humans occurs through the mouth or nose, and this critically important function is controlled by the brain, so without a head, breathing stops.

However, cockroaches do not have blood pressure like humans. These insects have an open circulatory system, where the pressure is significantly lower. After losing their head, the blood at the cut site simply coagulates.

These creatures breathe through spiracles—small openings located in various parts of their bodies. They direct air directly to the tissues through tracheae, and this process is not controlled by the brain, nor do insects need to transport oxygen through their blood.

But how can a cockroach survive without a mouth? Won't it feel hungry? Cockroaches are poikilotherms, meaning they are cold-blooded creatures. They require significantly less food than, for example, humans. Therefore, if the insect does not become ill or fall prey to a predator, it can live for several weeks without food.

Without a brain, a cockroach's body continues to function, performing simple actions and reflexes. This is due to the ganglia—clusters of nerve tissue distributed throughout each segment of the body that can perform basic nerve functions. All these features of the insect allow it to survive even after losing its head.