Skin-crawling experiment Humidity levels in the region of the museum have increased recently, Sepulveda said. Normally, Arica is arid - it is located near the Atacama Desert, the driest desert in the world (outside of Earth's polar regions).
Chile's changing climate may explain why the mummies are disintegrating, said Marcela Sepulveda, a professor of archaeology at the University of Tarapacá.They found that the skin began to fall apart after 21 days at high humidity.
To save the mummies, the museum will need to keep the humidity in the room where the mummies are stored between 40 and 60 percent, the researchers found. Higher humidity could cause more degradation, and lower humidity could damage the mummies' skin, Mitchell said.
"It hasn't rained in parts of that desert for 400 years," Mitchell said.
Efforts to preserve the mummies are underway. The museum's researchers are measuring and adjusting the humidity, temperature and light in the room where the mummies are housed on a daily basis, Sepulveda said.
But in the past 10 years, fog has come in off the Pacific, possibly because of climate change, Mitchell said. And "because there is more moisture around, the mummies have begun to disintegrate," he said.
The Chinchorro were a hunter-gatherer group of people who lived along the coast of modern-day Chile and Peru, and they mummified people from all levels of society.
These measures could help preserve the Chinchorro mummies, which are at least 2,000 years older than Egyptian mummies. Radiocarbon dating puts the youngest mummies at 5050 B.C., making them the world's oldest man-made mummies, Mitchell said. (Some older human remains may have been mummified by natural processes.)
"These aren't just kings, these are ordinary people," Mitchell said. [Image Gallery: Inca Child Mummies]
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Images: Chilean Mummies Hold Nicotine Secret Photos: Mummy Hair Reveals Ancient Last Meals In Photos: A Look Inside an Egyptian Mummy This story originally appeared on LiveScience.com.
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