When nuns at a monastery in Gower, Mo., exhumed the body of Sister Wilhelmina Lancaster to move it to a final resting place, they were reportedly surprised to find that her body showed few signs of decomposition four years after her death.
“Incorruptibility” — when a body shows little or no signs of decay after death — was thought of as an indicator of holiness in the Catholic and Eastern Orthodox churches for centuries. The Catholic Church doesn’t consider an incorrupt body to be automatic grounds for canonization, but the news has still prompted hundreds of pilgrims to visit Lancaster’s body, which was placed on display at the monastery’s church — and spurred questions about the feasibility of an incorruptible body.
“The condition of the remains of Sister Wilhelmina Lancaster has understandably generated widespread interest and raised important questions. At the same time, it is important to protect the integrity of the mortal remains of Sister Wilhelmina to allow for a thorough investigation,” the Diocese of Kansas City-St. Joseph said in a statement. “Incorruptibility has been verified in the past, but it is very rare.”
Yahoo News asked Heather Garvin, a forensic anthropologist and professor of anatomy at Des Moines University, to help demystify some of what happens after death — and the science behind it. Responses have been lightly edited for length and clarity.
Yahoo News: What does the decomposition process usually look like for a human corpse?
Garvin: During decomposition, the body will undergo several phases.
In early stages, you may get bloating or skin slippage as bacteria begin to do their job and tissues begin to break down.
This would be followed by putrefaction (or decaying of the tissues). As the tissues decay, they can become unrecognizable, and you may start to get some skeletonization.
The final stage would be complete skeletonization. While this sounds simple, it's not that simple. Instead of undergoing moist decomposition, tissues can become dehydrated and they can mummify. Mummified tissue can persist for long periods of time.
Does the type of burial (i.e., type of coffin or casket or the climate) play a role in how quickly or slowly a body would decompose?
Yes, the type of burial, material in which the coffin or casket is made out of, and the surrounding climate will all affect decomposition rates. Exactly how is not well understood, and this is because there are many other factors that would contribute to either a faster or slower decomposition rate.
Embalming is an obvious one, and embalmed bodies can preserve for very long periods of time.
A closed, anaerobic environment (lacking oxygen/airtight container) can also slow decomposition as bacteria responsible for much of the tissue breakdown need oxygen.
An airtight container would also mean that the body was not exposed to water, moisture, acidic soil, insects, etc.
There are so many confounding variables in the decomposition of a body that it is difficult to determine the effects of any single factor. It is also difficult to do large-scale studies of samples of individuals disinterred at specific lengths of time and under controlled environments.
The nun recently exhumed in Missouri had been dead for four years but reportedly showed almost no signs of decay. How common is that?
Exhumations of bodies four years after death are rare, so it is not easy to compare to larger samples. If someone asked me if it was possible to have a body in this condition after four years, I would say yes.
While the body was reportedly not embalmed, I would be curious as to whether there were any other cleansing rituals or preparations for the original viewing that could affect the decomposition.
All I have to work with is what I can see in the news articles. The hands look as though they are mummified. The photos, however, also show a kind of reflection or sheen on the hand surfaces, which makes me wonder whether anything was applied. What does the remainder of the body look like under the clothing? We see so very little of the tissue exposed in the photos.
If I have learned anything about decompositional rates, it is to expect the unexpected. I have seen decomposing tissue present in a case buried for eight years (no coffin — exposed to the soil and environment). In other cases, a body may become mostly skeletonized in weeks or months. It is highly variable.