The world's oldest mummies in Chile are at a threat from decomposition due to climate change. These ancient relics are even older than the Egyptian mummies of pharaohs and their decorated tombs.

According to Bernando Arriaza, a professor at the University of Tarapaca, the ancient Chincorro people who lived in the Atacama Desert of Chile started mummifying their dead around 5,000 years ago, while the Egyptians began much later in about 2600 BCE.

Since then the desert has preserved the mummies and other ancient remains and has given significant information about the Chincorro people to archaeologists.

According to archaeologists, the idea of preserving bodies as mummies came from observing the natural process the dead went through under the dry conditions of the desert. The mummies were also adorned with clay masks, reed blankets, human hair and other articles.

The desert region has been declared a World Heritage Site by UNESCO to help save the relics, however, it might not be enough. While there are many museums in the ancient city of Arica which display the relics from Chincorro culture in climate-controlled exhibits, the remaining antiques that are still buried in the arid desert are at risk.

"If we have an increase in sea surface temperatures, for example, across the coast of northern Chile, that would increase atmospheric humidity," said Claudio LaTorre, a paleo-ecologist at the Catholic University of Chile. "And that in turn would generate decomposition, (in) places where you don't have decomposition today, and you would lose the mummies themselves." 

Other ancient clues in the region that archaeologists could find may also be lost.

"Human-induced climate change is one aspect that we're really worried about, because it'll change a number of different aspects that are forming the desert today," said LaTorre. 

Arriaza has been advocating the preservation of mummies and has been working to raise awareness on the matter.

"It's a big, big challenge because you need to have resources," Arriaza said. "It's everybody's effort to a common goal, to preserve the site, to preserve the mummies." 

(With inputs from agencies)