7,000-year-old Chinchorro mummies are turning gelatinous

The Chinchorro mummies of Chile survived more than 7,065 years without deteriorating until about 10 years ago, when moisture began to allow bacterial growth that is making them turn gelatinous and black, says an American university professor who examined the mummies. Experts are taking steps to preserve them.

Moisture in the air and on the mummies is allowing bacteria to grow, said Ralph Mitchell, a Harvard University professor emeritus of applied biology. About 120 mummies, which radiocarbon dating date from 5050 BC and before, are rapidly deteriorating in the archaeological museum of the University of Tarapacá in Arica, Chile, on the northwest coast of that South American country.

The university is near the Atacama Desert, in some parts of which it hasn’t rained for nearly 400 years.