From a biological perspective, death occurs when the bodily functions that are vital to sustaining life cease. It can be brought about by a number of factors ranging from ageing, predation (being hunted for food), illness and diseases, hunger, dehydration, malnourishment, homicide, or suicide. The human body goes through some interesting changes before the process of decomposition begins. Even though topics related to death is very morbid and rather unpleasant, it is important from a scientific perspective to know what happens to your body after you die. This article follows a timeline – from the moment right after death to the beginning of decomposition. But first, how is “death” scientifically defined?
Clinical Death v/s Biological Death
In biology, death is classified into Clinical Death and Biological Death. Clinical Death is what happens when a person’s respiratory system fails, or simply stops breathing. Organs such as the brain and the heart might still be alive and functioning for a limited time depending on what has happened to the person. But this window closes if the body is not resuscitated and what follows is called biological death. In biological death, the person cannot be revived as the brain cells have already died due to lack of oxygen. Typically after a person has stopped breathing, they have a window of 4 to 6 minutes before some brain damage begins to occur. After 6 to 10 minutes, brain damage is likely, and beyond 10 minutes, irreversible brain damage is observed.
Moments After Death
The moments after a person has been declared biologically dead, Primary Flaccidity occurs. What this means is- the body loosens up, the jaws fall open, muscles tension is relaxed, eyelids loosen up, the skin will sag and joints become flexible. Parts of the body will flatten over the surface on which it rests and it exhibits almost no resistance. Within a few moments, Pallor Mortis is observed, i.e., the skin takes on a pale complexion and this more pronounced in decedents that have white or light skin. The main reason for this is lack of capillary action within the blood vessels after the blood stops circulating. In other words, the blood stops flowing and sinks to the lower parts of the body due to gravity. This is followed by the “death chill” or Algor Mortis. Here, the body begins to cool down, from 37-degree Celsius (normal body temperature) to the ambient surrounding temperature. And finally, as all muscles are relaxed, the sphincter tone loses control and as a result, faeces and urine pass.
2 Hours After Death
Since the circulation of blood has ceased, the blood begins to accumulate in the parts of the body where it is in contact with the ground. This phenomenon is called the Livor Mortis. And if the body is left undisturbed long enough, then a reddish-purple discolouration is observed in the parts where blood has accumulated. Three or four hours after death, chemical changes at the molecular level starts affecting the body and it results in Rigor Mortis. It is characterized by the general stiffness throughout the body. It begins with the eyelids, the face, neck, and jaws. It spreads through the chest, abdomen, arms, legs and eventually to the fingers and toes. Infants and smaller children do not exhibit rigor mortis due to their smaller muscle mass.
12 Hours After Death
Rigor mortis completely stiffens up the body roughly 12 hours after death. At this point, it becomes difficult to manipulate or move the arms or legs of the deceased as it is very stiff. Also, other factors affect the rate of rigor mortis starting from the age of the decedent, the gender, physical condition, ambient temperature etc. Later, the body begins to loosen up again due to the chemical changes that occur in the cells. Eventually, rigor mortis recedes in the reverse order, starting from the fingers and toes until it reaches the neck and face. This is known as secondary flaccidity. Skin begins to dry up, giving the appearance that your nails and hair have grown.
42 Hours After Death
Two or three days after death, a greenish discolouration starts in the lower right abdomen. This eventually spreads over the whole abdomen and then to the arms and legs. The cell structure in the organs starts breaking down with the help of bacteria that was already present in the gut. This process is known as putrefaction. At this stage, terrible stench starts emanating from the body as the process of decomposition is in full swing. Weeks after death, maggots consume almost 60% of the fat and soft parts of the body. Eventually, the skin colour turns from purple to black as bacteria continue to breakdown the body. If the body is left at 10 degrees Celsius, all the remaining flesh, skin and tissues will decompose in about 4 months until just the bones are left.