The five stages of decomposition

Decomposition of a corpse is a continual process that can take from weeks to years, depending on the environment. It is a natural process involving the breakdown of tissues after death. To illustrate the process of decomposition I’ve created these cards with the five stages.

Fig.1 The five stages of decomposition.

Fresh
Shortly following death, circulation fails, and blood drains to the lower parts of the body, creating a blue discoloration. Muscular tissues become gradually more rigid. Cellular enzymes begin breaking down surrounding body tissue.

Fig.2 Fresh (aka autolysis).

Bloat
Gases begin to accumulate within the body, causing a bloated appearance, and force fluids to escape from wounds and body orifices. Ultimately, the pressure of gases and fluids can rupture the skin.

Fig.3 Bloat.

Active decay
Maggots and aerobic microorganisms enter the body tissue, leaving and returning as they go through stages of their lifecycle. Fluids accumulate around the body, accompanied by strong odors.

Fig.4 Active decay.

Advanced decay
Maggots leave the body in a state of advanced decay, with a corresponding increase in soil carbon and nutrients such as phosphorus, calcium, magnesium and, in particular, nitrogen.

Fig.5 Advanced decay.

Dry remains
All soft tissue is gone, leaving only dry skin, cartilage and bone bleached white where it has been exposed to the elements. There may be increased plant growth as a result of additional nutrients in the soil.

Fig.6 Dry/skeletonized remains.

How quickly a body decomposes depends on several factors: surrounding temperature, whether the body is buried or exposed to air or water, and the number of bacteria present. A body that is exposed to the elements such as air and water will decompose faster and have more insect activity than a body buried or confined in a sealed space. In similar fashion, a body decomposing in warm temperatures will break down faster than if it is left in a cold environment.

The exception to this is if the temperature is so hot that moisture, a needed component in decay, isn’t present. In that case, the body mummifies and dries out. However fast or slow a body decomposes and goes through these five stages, it is nature’s way of releasing the materials back into the earth so new life can be born again.