Why a South American Mummy Melted into Black Ooze

With the thriving of tropical diseases in regions they never touched before, an Arctic Sea rapidly melting, at temps that could increase by one degree Fahrenheit per decade, and record breaking storms, all tied in with what could have been a deliberate gag order in Florida earlier this week, it seems like the consequences of climate change are more frightening than anything conjured up by a Hollywood action movie – details that were far more adverse than the 2004 epic The Day After Tomorrow. The latest unpleasant effect of increasing tropical temperatures, however, sounds a bit more like something out of a horror movie than real life – a centuries old mummy, unearthed in the Atacama desert, is brought to a museum in Chile, where the corpse slowly degrades into black ooze – perhaps a sort of dark metaphor for the destruction of human lives from fossil fuel.

Unfortunately, this is beyond metaphor. Over 100 mummies kept in the Universidad de Tarapacá of Arica, Chile — have begun degrading.

“The tissue change is reflected in the appearance of dark and bright spots,” explained Marcela Sepulveda, who works as an archaeologist at the Universidad de Tarapacá’s museum.

These mummies are at least seven millennia old, belonging to a tribe known as the Chinchorro, who once dwelled along the South American coastline, throughout what is now northern Chile and into southern Peru and subsisted primarily on fish from the nearby Pacific Ocean. They were at least as ancient as the Mesopotamians, predating ancient Egyptian kingdoms by thousands of years. Perhaps the most surprising aspect of the Chinchorro, however, was their practice of mummification, which predated Egypt, and unlike the Egyptians who typically only mummified royalty or members of the priesthood, the Chinchorro preserved all their dead in the same way. It was a sacred rite that did not discriminate against age or economic status.

The first of these mummies were found in the Arica desert, just inland from Chinchorro civilization, back in 1917, known for being one of the driest places on Earth.

Hundreds have been unearthed, but although the preservation may have worked well for 7,000 years, that’s beginning to change.

“The tissue change is reflected in the appearance of dark and bright spots,” explained Marcela Sepulveda, an archaeologist at the Universidad de Tarapacá, by email.

While the ones in the museum are deteriorating slowly, new mummies are being found in an already damaged state, according to Sepulveda. “When you excavate mummies you can see that degradation is already there,” she said. The cause behind this? An altering climate.

Arica may no longer be so dry. The city has already reported a rise in both precipitation and humidity in recent years. “Everybody say(s) that here,” she averred. Back in 2013, Christopher Burt, a weather historian also noticed a difference in Arica’s weather, a change evident in weather records kept between 1971 and 2000.
While this may not be directly attributed to humans, it clearly represents a change in climate that has real implications for human life, however unplanned and small it may seem. Ralph Mitchell, a Harvard microbiologist, teamed with the Chilean archaeologists to find out why the specimens were becoming more decrepit. Many of them were uncovered in the 1980s and only about ten years ago did researchers notice signs of deterioration due to changes in the air. “Our colleagues in northern Chile say it’s terribly obvious that the place is foggy a lot more than it ever was,” Mitchell said.

Mitchell and two of his Harvard colleagues worked with Sepulveda and one of her fellow researchers to determine if climactic change could be responsible, hypothesizing that a greater amount of airborne moisture was enabling levels of bacteria to grow and initiate deterioration cycles on these ancient relics.

Testing both samples of mummy skin and also dried pig skin, in alternating conditions of humidity allowed them to analyze the types of microbes that could grow off of the skin. More humid environments were invitations for what Mitchell called bacterial “opportunists” to begin their work – finding nourishment in the dried skin. For their experiment, Mitchell’s team used common variations of skin bacteria.

While the research has yet to be published, the findings were already publicized by Harvard earlier this week. Mitchell’s work in microbiology has already led him to work on the preservation of historical artifacts – ranging from ancient book manuscripts in museums to the Apollo spacesuits.

The fate of the Chinchorro mummies are just one example of how climate change can significantly impact world artifacts, emphasizing again how climate change has had a sizable impact on so many branches of science. UNESCO World Heritage Centre has been behind this problem for some time, addressing it back in 2007 in a report to the United Nations, stating that “the impacts of climate change are affecting many World Heritage properties and are likely to affect many more, both natural and cultural, in the years ahead.” Obvious spots already are the Parthenon in Greece which has been affected by air pollution for decades, and also many American landmarks in Virginia and Maryland that may have to deal with rising sea tides.

The U.S. Agency for International Development has also shared its concern over the impact of climate change on these sites, noting where in India there has been a problem similar to that seen in the Arica desert: “Buildings in the rare medieval city of Leh in Ladakh, India, were constructed in a high altitude desert environment and are ill suited to current increases in precipitation.”

Archaeology magazine listed a similar example several years ago, occurring in a different climate. The Scythians, an ancient Iranian nomadic culture, left burial mounds in modern Siberia as tribute to their warlords, known as “kurgans.” As the permafrost near Siberia is beginning to thaw for the first time, leaving craters in its wake, these burials are exposed to the air for the first time in centuries, leaving them vulnerable to irreversible cases of deterioration.

“Historic marbles in the outdoor environment are at risk from climate change,” Mitchell said, naming a prime victim of this extreme weather – many statues from the classical Greek and Roman Age of Antiquity. While many climatologists and politicians are working to save the planet’s future from the dangers of climate change, it becomes easy to forget that much of the past may end up disappearing as well.