The preservation time of skeletons is closely related to the surrounding environment.
Human bodies, lacking protective skin or fur, can begin to noticeably decompose after about a week in a hot, humid environment.
Typically, a body exposed outdoors for about a month will have its skin and muscles fully decomposed, leaving only the fascia.
In about two months, the body will become skeletal; human bones exposed outside can last for at least a year, but under suitable conditions, they generally decompose completely within five years, leaving no trace.
Bodies buried underground decompose more slowly than those on the surface.
This is because lacking oxygen below ground reduces the activity of aerobic bacteria, slowing decomposition.
The specific decomposition time depends on the soil's moisture and temperature.
Generally, a body buried underground will completely skeletonize after one to three years.
