Mummification
Why don't mummified bodies rot?
Mummification just means a corpse that has been preserved without rotting. This can happen a number of different ways.
Some mummification is intentional, like the famous Egyptian mummies. Their bodies were preserved by drawing out all the moisture with salt. This, combined with the natural dryness of the Egyptian desert, preserved the bodies.
Removal of moisture is key. Bodies rot by being consume by bacteria which require moisture to live.
An article helpfully entitled Why don’t mummies rot?, says:
Bodies rot because bacteria thrive in the moist conditions of decaying flesh and organs. Bacteria can’t live, however, where there is no water.
So, a mummy was either purposefully dried out (like the famous Egyptian mummies), or it was left in a place where bacteria couldn’t survive.
The tops of mountains have both cold temperatures and low moisture. This explains why the 200+ bodies on Mount Everest (like the infamous Green Boots) or the Children of Llullaillaco don’t rot – they’re at a high enough altitude that their is very little air, and therefore very little moisture.
In 2016, a yacht was found adrift off the coast of the Phillipines. Onboard were the mummified remains of the lone sailor – a 59-year-old German man. He had died of natural causes, and his body had been preserved by the salty air which drew out all the moisture.
“The air, heat, and saltiness of the sea are all very conducive to mummification,” said Peter Vanezis, forensic pathology professor at Barts and The London School of Medicine and Dentistry. “It starts within two to three weeks. The fingers and other extremities … dry quickly, and in a month or two they are well gone.”
From an article entitled, Do Mummies Decompose?:
the accidental mummifications involved the bodies being kept in conditions ideal for preservation. Deserts, peat bogs, and ice all protect dead bodies from being eaten, as many microbes find extreme heat, acid, or cold inhospitable.
[…]they stripped the bodies of nutrients and kept them dry, ensuring they would last for centuries to come
Why I Looked It Up
Just got to wondering one day. We accept a “mummy” as a horror movie trope and artifact of history, but I started wondering what separated them from bodies that just decompose out of existence. There had to be some reason why mummification happened instead of decomposition.
Postscript
Added on
From a description of some mummies in Italy.
The natural mummification of the Mummies of Venzone is due to particular environmental conditions that occurred in some tombs of the Cathedral in which the Hypha bombicina Pers developed, a mold with the property of dehydrating tissues inhibiting decomposition.