In what ’s now Chile and Peru , a hunter - gatherer society called the Chinchorro had been mummifying their community members — men , women , children , even fetuses , and not just king and the elite — as far back as 5050 B.C. based on carbon 14 go steady . That ’s at least two thousand years originally than the dry gangrene of ancient Egyptian Pharaoh of Egypt . But in the last decade , these mummy — the old man - made mom in the world — have begin to break down , and at an alarming rate . In some cases , these millennia - old mamma were rapidly turning into black gook . Now , an scrutiny of the decay mummies reveals how rising humidity levels are to fault .
“ In the last ten years , the outgrowth has quicken , ” saysMarcela Sepulveda from the University of Tarapacá . Nearly 120 Chinchorro mummies are housed in the university’sSan Miguel de Azapa Museumin Arica , Chile . The elaborated process begins with an extraction of the head and pipe organ . The body would then be rebuild with fibers , and the skull cavity would be filled with shuck or ash tree . The contribution would then be sew together back together using reed , with a stick observe the spine flat and attached to the skull . Afterwards , an embalmer would restore the skin , sometimes using patch of ocean lion skins , and the entire mammy was then covered with a paste . Over the 3,000 long time of Chinchorro mummy - making , the library paste has changed from manganese to ocher to mud .
To detect a way to stop the deterioration , Harvard ’s Ralph Mitchelland colleagues first had to figure out what was causing it . “ We knew the mummies were degrading but nobody understood why , ” Mitchell says in anews tone ending . “ This sort of degradation has never been studied before . ”
After examining sampling of both damaged and undamaged skin , the team discovered that the degradation was due to the mummies ’ microbiome . The researchers then isolated the microbes present on the peel and culture them in the research laboratory . Before subjecting the precious sample distribution to test , they experimented with pig bed hide and found that the skin surrogates ( complete with microbes ) begin to degrade after 21 days of high humidness . When they repeated the exam with the genuine mummy skins , they confirmed that advance moisture in the air was prejudicial .
“ The key watchword that we use a circumstances in microbiology is opportunism,”Mitchell explains . “ With many diseases we come across , the microbe is in our consistence to lead off with , but when the surroundings change it becomes an self-seeker . ”
And humidness stage in Arica have been on the wage hike , according to Sepulveda . The ideal humidity range is between 40 and 60 percentage . Below that , acidification could damage the mummy , but above that , “ the aboriginal micro-organism are going to chew these guy rope right up,“Mitchell tells Live Science . However , while this can be controlled in a museum , “ how do you keep them outside the museum?”Mitchell asks . “ Is there a scientific answer to protect these important historical object from the devastating consequence of climate variety ? ” one C of these 7,000 - year - previous mummies might still be buried beneath the flaxen control surface of those coastal valleys .
image : Vivien Standen ( top , 2d ) , Marcela Sepulveda ( third )
