If you’ve been keeping up with The Post-Mortem Post’s Decomposition Week Special, you already know all there is to know on the subject of Pallor Mortis, Algor Mortis, Rigor Mortis, Livor Mortis, Putrefaction, Biotic Decomposition and Skeletonization. We have good news for those of you who haven’t gotten your decomposition fix just yet because now we will move on to The Other Stages of Decomposition: Fresh, Bloat, Active Decay, Advanced Decay and Dry Remains.
“Fresh” is used to describe the time between death and the first signs of bloat. This stage includes Pallor Mortis, Algor Mortis, Rigor Mortis and Livor Mortis. Although no obvious changes can be observed on a “fresh” corpse in appearance or smell, bacteria has already begun digesting the body internally. Within a few minutes of death or the exposure of a corpse which was in a protective environment, Calliphoridae, commonly known as “blow flies”, sarcopha gidae (flesh flies), muscidae (species of fly) and ants begin to arrive. In 1-3 hours these insects will begin laying eggs inside the natural orifices of the corpse (usually the head and anus) and in any wounds present.
Bloat begins with the inflation of the abdomen due to a build up of bacterial gasses. Purge fluids may also begin to exit the nose and mouth. At this time, change in the corpse’s flesh tone will become evident as well as marbling. The corpse will begin to let off a distinct odor during bloat as it begins to Putrefy. Blow flies, flesh flies and muscids continue to arrive and lay their larvae in the corpse’s orifices and wounds. During bloat, Piophilidae (cheese flies), Fanniidae flies, Staphylinidae (rove beetles), Silphidae (carrion beetles), Coleoptera and Cleridae beetles arrive.
3. Active Decay
Active decay is apparent when the corpse begins to “deflate” with help from Dipteran fly larvae that puncture the skin, releasing bacterial gasses. The corpse will begin to take on a wet appearance due to the liquefaction of tissue as strong odors persist. During active decay, flesh on the head and anus will be removed by insects which will then begin to eat away at the chest and abdominal cavities. The Calliphoridae fly larvae is generally the most abundant species during this process and Sepsidue (lesser dung fly) arrive.
4. Advanced Decay
At the onset of Advanced Decay, also known as “Post-Decay“, most flesh has been removed from the corpse, though some may remain in the abdominal cavity. Most odor begins to dissipate, as well and larvae either leave, or grow into adults. No new larvae will be produced in a corpse in Advanced Decay, and far more adult insects are present. Dermestidae (skin beetles) will begin to arrive.
5. Dry Decay
Dry Decay breaks down into Separate Remains and Dry Remains; However, the stages are so similar they are next to impossible to differentiate. Due to this, both are lumped together as Dry Decay. At this time, little to no odor exists and most insects which were previously feeding on the corpse have left. During Dry Decay centipedes, millipedes, isopedes, snails and cockroaches may arrive.
Decay can be delayed by many factors discussed during Decomposition Week [links available at end of article]. Insects involved in the decomposition process may also be subject to factors which aid or hinder their consumption of a corpse. For instance, insects would be delayed when consuming the body of a victim of arsenic poisoning. Unsurprisingly, traces of cocaine left in a corpse cause insects to work very rapidly. Of course, a body may only decompose in this way when on a Body Farm or similar environment where it is exposed to open air and somewhat protected from large scavenging animals.
DECOMPOSITION WEEK EXTENDED (slightly): Come back WEDNESDAY April 15th to learn about Adipocere/Saponify and other forms of natural preservation. In an effort to include more information without creating an overload of information we have chosen to split today’s scheduled article into two separate pieces. Apologies to anyone who was looking forward to learning about spontaneous mummification today!
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