Atacama alien-mummy mystery solved

The tiny corpse which the Chilean hunter, Osca Munoz, found near a church in a ghost town called La Noria in 2003 triggered the fantasies of many superstitious people. Many thought that the tiny body, with an unusually formed head, was that of an alien. There's even been a documentary movie about "Ata" the mummy — the skeleton was named after the Atacama Desert, where it was found. 

Now, the speculation can stop. Researchers say they used genetic analysis to prove that Ata was a tiny premature baby, misshapen by hereditary disease. The team of scientists from the University of California, San Francisco and Stanford University published their findings in the journal Genome Research.

Circumstances of death remain unclear

It is still uncertain, however, whether the child was stillborn or died shortly after birth. 

But the scientists did discover other details during their five-year-long investigation. For instance, they found multiple genetic mutations. Those were responsible for specific malformations of bones and the skull — typical for short stature, scoliosis (a twist of the spinal column) and deformations on muscles and bones. Besides the deformed skull, the body also had only ten, rather than the usual twelve pairs of ribs.

Microbiologist Garry Nolan from the Baxter Laboratory for Stem Cell Biology at Stanford says his interest in the case was triggered when he received a picture of the mummy from a friend.

5 years of research

Besides taking several samples from humans, the scientists also used reference genome samples from chimpanzees and rhesus monkeys. This helped them to rule out secondary theories about the corpse's heritage.

A comparison to the genomes from other people in the region proved that the corpse was of Chilean ancestry. A chromosome analysis showed that Ata was a girl. The scientists extracted the material for the gene sequencing from one of the ribs. 

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Ralph Lachman from the Department of Pediatric Radiology at Stanford found that several parts of the girl's bones looked like they were those of a 6 or 7-year-old.

The scientists concluded that Ata had suffered from a rare bone degeneration, which results in a faster aging of bones. The fact that Ata's body was mummified by the dry and hot desert climate helped the researchers draw their conclusions. They estimate that Ata died roughly 40 years ago.

Was it a case of grave robbery?

The circumstances of how and when Munoz found Ata's body remain unresolved. Munoz did not disclose the exact date or time he found the skeleton, or where exactly he found it.

Munoz said the body was wrapped in a white cloth when he found it, with a purple ribbon inside a leather bag. That, combined with the fact that the body was found near a church — and a graveyard — suggests that the find had something to do with grave-robbery, which said to be common in that area.

That may lead researchers to conclude that Ata had most likely received a ritual burial — until her resting place was disturbed by treasure hunters, like Munoz, who sold the mummy to an antique dealer.

After that, Ata changed hands several times. The last buyer was a collector in Spain.

Nolan has called for the mummy to be buried back in Chile. "I think it should be returned to the country of origin and buried according to the customs of the local people," the scientist said.

fs/cd (dpa, afp)