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Northern Chile is home to some 7,000-year-old mummies, some of the oldest mummies in the world. But scientists say the mummies are in danger. NPR's Jasmine Garsd has this story about mummies, strange oozing substances and a mysterious fog.
JASMINE GARSD, BYLINE: A few years ago at a conference in Dublin, Harvard professor Ralph Mitchell was approached by a French scientist with a question he never expected to be asked - what do you know about mummies?
RALPH MITCHELL: And the answer is very little. I'm a microbiologist.
GARSD: The Frenchman was asking on behalf of Chilean archaeologists who were very concerned about the fate of their own famous mummies, the ancient Chinchorro mummies. Their skin had begun to turn into a shiny, translucent dark coffee-color, hard to the touch. From afar, it looked like the mummies were turning into black jelly.
MARCELA SEPULVEDA: (Foreign language spoken).
GARSD: Marcela Sepulveda is an archaeology professor at the University of Tarapaca in Chile. She says the Chinchorro mummy-making process was very complex. The Chinchorro were hunter-gatherers on the Pacific Coast where Peru and Chile are today. They were good at making mummies and the region's climate helped them. The Atacama Desert is the driest in the world. On average, it gets less than 1.5 centimeters of rain every year, so bodies buried there are often naturally preserved. But the Chinchorros made an art out of it.
SEPULVEDA: (Foreign language spoken).
GARSD: She says the mummies tend to be extended, lying on their side and buried in the sand. There are a lot of variations in the methods. Sometimes the body was molded with fibers or clay. In other cases organs were extracted and the bodies stuffed. Climate and expertise made the Chinchorro mummies last for 7,000 years. Perplexed, the Chileans contacted Professor Mitchell. Many years ago, Mitchell investigated the dark stains on the walls of King Tut's tomb. This time, he was sent a tiny piece of mummy to test. Mitchell says people always ask him if it was some mysterious ancient pathogen worthy of an Indiana Jones movie. But what he found was a very common bacteria.
MITCHELL: The key word is opportunistic. And its many ways the same as with a number of human diseases. The organisms are there and are waiting for an opportunity.
GARSD: Mitchell explains that everything around us is covered in bacteria.
MITCHELL: There are no shortage of bacteria and mold all around us, so the same thing is true with these mummies. The skin is covered in very common microorganisms and as soon as you add moisture - think of bread in your refrigerator, same kind of thing.
GARSD: So why not place all the mummies in a dry, cold area? Because there are hundreds of Chinchorro mummies and housing them will require careful planning and investment. And once the bacteria question was answered, there was an additional piece to the puzzle - how do mummies in the driest region in the world get wet?
MITCHELL: Over the past 10 years, the climate has changed along the coast and the fog is rolling in, something never seen before. They're getting fog - cool, wet days - and the moisture is settling on the mummies.
GARSD: But it's more than just about mummies.
MITCHELL: As the climate changes globally, I don't think we've ever thought about cultural heritage materials, but they are at risk.
GARSD: And solving that, Mitchell says, is the bigger puzzle. Jasmine Garsd, NPR News. Transcript provided by NPR, Copyright NPR.