Science of a Dead Body


Can dead bodies move like us? Do they feel anything? These questions are asked often.

Not really, dead bodies don’t function as the living ones, but there are things happening inside a dead body that might amaze you. We see the dead body but not the things happening inside.


There are some chemical reactions that happen inside a dead human or animal body. These reactions make the muscles of a dead body gradually harden up. This step by step process is known as Rigor Mortis. 

Let’s see how this process takes place:

After death of a person, firstly their heart stops circulating blood. This initiates the flow of blood from Capillary to arteries. Gravity makes the blood flow to the feet if the body is standing or to the back if the body is lying. At this point muscles start to loosen up.

After this the body temperature starts to drop. Body temperature decreases by 2 degrees after the first couple of hours from death. It continues to decrease by 1 degree after each hour. At one point this decrease in temperature comes to a halt. This process is known as Algor Mortis. Temperature of the dead body may fall to 15 degrees.

The very next step is Rigor Mortis. The decrease of Adenosine Triphosphate (ATP) triggers Rigor Mortis. It takes around 3/4 hours after death for this process to start.

The dead body keeps hardening up for up to 8 hours after death, though some body parts may still be flexible. All the muscles harden up within 8-12 hours. And continue to stay hard for the next 12 hours.  24-36 hours from death, the muscles start to loosen up again.

The whole process goes on for about 24-36 hours. Sometimes it might require 48 hours. If the dead body had caught Pneumonia or any type of cold, it might delay the Rigor Mortis process.