The infamous ancient Chinchorro mummies, which have been preserved in the country of Chile for more than 7,000 years, face a very grave threat (excuse me I had to) rising levels of moisture.
The fast deterioration began within the last decade and has affected some of the 120 mummies that are stored at the University of Tarapacá’s archeological museum in the northern port city of Arica, the scientists said.
It was not clear why only some of the 120 mummies started decaying into black ooze, so Chilean preservationists asked Mitchell and his colleagues to study the microflora, or namely the bacteria that is found on the mummies.
Extensive examinations showed that the bacteria do not originate from ancient organisms. At best they are simply bacteria that thrive on people’s every day skin, Mitchell said. He mentioned the bacteria is an “opportunist” reason being; as soon as the correct temperature and perfect moisture appeared on the scene, they started to use the skin as nutrients.” How convenient it must be for them.
Unless the mummies can be preserved with the correct temperature and humidity environment, “the native microorganisms are going to chew these guys right up,” Mitchell stated.
Skin-crawling scientific tests
In their examinations, Mitchell and his crew raised the air’s humidity levels from dry to damp, observing how each humidity level affected the skin of the mummies. The preservationists did their initial tests on pig skin, to limit the amount of mummy skin they needed to use. Thankfully they are smart enough to do this.
Humidity has increased steadily in the region of the museum recently Sepulveda said. Normally, Arica is arid — it is found near the Atacama Desert, the driest desert in the world (outside of Earth’s polar caps).Chile’s ever changing environment may explain why the mummies are decaying rapidly, said Marcela Sepulveda, a professor of archaeology at the University of Tarapacá.They soon found that the skin began to fall apart after 21 days under high humidity conditions. To preserve the mummies, the museum will need to maintain the humidity in the room where the mummies are stored. The ideal levels should be stalled between 40 and 60 percent, the scientists found. Increased humidity could cause more decaying, and unfortunately lower humidity could damage the mummies’ skin too, Mitchell said.
“It has not rained in parts of that desert for 400 years,” Mitchell said.
But in the last decade, fog has come in from the Pacific, possibly because of environmental change, Mitchell said. And “because there is more moisture around, the mummies have begun to decay,” he said. Here we go again blaming global warming but maybe it is the real culprit? Who knows.
Efforts to save the mummies are in progress. The museum’s preservationists are measuring and adjusting the humidity levels, temperature and even the light in the room where the mummies are stored on a daily basis, Sepulveda said.
By the Way
The Chinchorro were a hunter and gatherer tribe of people who lived along the coast of modern-day Chile and Peru. Not knowing that we would be observing them in the future they went ahead and mummified people from all levels of society. Legendary people never die!
These cautionary measures could help save the Chinchorro mummies, which are a minimum of 2,000 years older than Egyptian mummies. Radiocarbon dating puts the youngest mummies at 5050 B.C., making them the earth’s oldest man-made mummies, Mitchell said. (Note: Some older human remains may have been mummified by natural processes.)