Climate change is bringing rain and humidity to usually dry and arid Northern Chile, causing ancient mummies to decompose as they are exposed to increased moisture and the elements. The phenomenon puts some of the world’s oldest known mummies at risk of deteriorating after thousands of years of artificial and natural preservation.
The mummies were created by the people of the Chinchorro culture, a fishing community who lived in what is now Chile and Southern Peru from 5,000 BC to 500 BC. They carefully prepared their dead by removing skin and organs and filling out the bodies with animal skins or clay and reeds. Some even had their original skin put back onto reshaped bodies, as if they were reupholstered for the afterlife.
Chinchorro burial sites have produced the remains of adults, children, and even babies laid to rest in shallow graves. The Chinchorro used different items, including human hair wigs, feathers, and clay masks to adorn the dead. Some mummies are black from being covered in a manganese paint; others are red from ochre paste made from red clay.
The bodies found in the Atacama Desert date back to 2,000 years before the Egyptians began preserving bodies, making them the world’s oldest known artificially preserved mummies. They’ve survived because the Atacama Desert is generally one of the driest places on the planet, but climate change has brought precipitation and humidity to the area. And while many of the mummies have been removed and placed in museums, there are still many in the desert, some of them deliberately re-buried by archaeologists in an attempt to reduce exposure.
Over the past decade, scientists have noticed that the bodies been deteriorating at an accelerated rate, with some even growing mold. In a 2015 report from the Harvard School of Engineering and Applied Sciences, scientists confirmed that rising humidity in the desert was making the mummies less likely to stay well preserved. That same year, it rained more than 2 inches in the Atacama Desert; the equivalent of several years’ worth of rain, according to the National Oceanic and Atmospheric Administration.
Benardo Arriaza, a Chinchorro expert at the University of Tarapacá in Arica, said that the different materials found at the sites, along with the weather changes and a lack of funding, make it difficult to preserve the bodies. “The type of deterioration varies according to the types of mummies and materials,” he explained via email. “Those bio-archaeological materials that have more soft tissue or organic residues can be more affected or susceptible.”
It’s hard to tell just how many mummies are buried in the area, and archaeological teams are often overwhelmed by the effort to save them. But Arriaza is hopeful that there is potential to improve how the mummies are preserved, so that Chile does not lose a crucial part of its history.
“A new archaeological museum is being built [in Chile],” he said. “This will be a wonderful opportunity to build up to new standards, code in conservation, exhibitions, and collection management... the Chinchorro represents an early emotional and artistic expression of ancient populations, a reflection of collective grief as well as hope for a better life. The mummies have been preserved for thousands of years, and we are doing everything we can to ensure their preservation.”
Climate change isn’t just a threat to the history of the Chinchorro: It’s affecting archaeological sites around the world. In the UK, sites that date back 4,000 years to the Roman era are in danger of decomposing as the peatlands that preserve them dry out, exposing artifacts to the elements. In Alaska, an indigenous archaeological site could disappear as permafrost that used to act as a buffer quickly thaws. Researchers worldwide are rushing against time to save human history as extreme weather changes our landscapes.