Earlier this year, scientists from Stanford University in the US concluded that a strange skeleton known as the Atacama Mummy belonged to a human girl whose physical malformations were the result of several severe genetic mutations. A team of international experts is now questioning these findings, and accusing the scientists of breaching standard research ethics.
The Atacama Mummy, or Ata as it’s known, was discovered 15 years ago in a deserted Chilean town in the Atacama Desert. The specimen is only about six inches long, it’s missing a pair of ribs, and it has a highly deformed head and face. Naturally, some UFOlogists figured the mummy was of extraterrestrial origin, prompting its appearance in a short documentary.
Scientific research suggested otherwise. A 2013 paper led by Garry Nolan, an immunologist at Stanford University, concluded that Ata was human, and that the skeleton’s bones gave the impression that it was between the age of six and eight years old when it died, though such an age would have be impossible. Earlier this year, Nolan, along with colleague Atul Butte, director of the Institute for Computational Health Sciences at the University of California-San Francisco, conducted a follow-up analysis. This paper, published in the science journal Genome Research, presented evidence showing that a series of genetic mutations were responsible for the strange features seen in the malformed specimen. The researchers concluded that Ata was a girl of Chilean descent who was a developing fetus at the time of her death, and that she suffered from a rare bone-aging disorder.
Within days of the study being published, a controversy emerged. The Chilean National Monuments Council launched an investigation, saying the mummy’s remains may have been acquired through illegal smuggling and grave robbing, and that the research was wholly inappropriate. Some Chilean scientists went so far as to say that Genome Research paper should be retracted.
Now, some four months after the paper was published, Nolan and Butte are facing another attack, this time from an international team of experts led by Sian Halcrow from the University of Otago, New Zealand. Their new paper, published today in the International Journal of Paleopathology, claims that Nolan’s research is replete with errors and misinterpretations, and that a genetic study probably shouldn’t have been conducted in the first place.
The authors of the new paper found “no evidence” of the skeletal anomalies described in the Genome Research paper. The abnormal characteristics described by Nolan and Butte, the authors say, are consistent with normal fetal skeletal development.
“We are experts in developmental human anatomy and archaeology, and the mummy looks normal for a fetus around 15-16 weeks gestation,” said Kristina Killgrove, a bioarchaeologist at the University of North Carolina at Chapel Hill and a co-author of the new study, in an interview with Gizmodo. “To the average person, I understand how Ata could look odd, but that’s because the average person doesn’t see developing fetuses or mummies.”
The researchers, for example, found no evidence of the bone abnormalities cited in the Genome Research paper, nor any evidence in support of the assertion that Ata’s bones gave the appearance of someone aged six to eight years. The missing 11th and 12th ribs is normal for a fetus of this age, the researchers say, as these ribs have yet to fully form.
As for the misshapen skull, the researchers refer to a number of possibilities, including a process called “plastic deformation,” where the skull, owing to heat pressure, becomes deformed when buried in the ground. More plausibly, the researchers say Ata’s cranial bones were “altered” by the mother’s cervix during delivery in a process known as moulding—a phenomenon sometimes seen in severe preterm fetuses. “The ‘elongated cranium’ of Ata is therefore phenotypically normal for a preterm foetus that has been delivered,” write the researchers in the study.
Finally, the researchers found no skeletal evidence of the genetic conditions cited in Nolan’s most recent paper.
“Unfortunately, there was no scientific rationale to undertake genomic analyses of Ata because the skeleton is normal, the identified genetic mutations are possibly coincidental, and none of the genetic mutations are known to be strongly associated with skeletal pathology that would affect the skeleton at this young age,” said Halcrow in a statement.
The flawed nature of the Genome Research study, the authors argue, highlights the need for interdisciplinary research approaches, which in this case should’ve involved experts in osteology, medicine, archaeology, history, and genetics. “A nuanced understanding of skeletal biological processes and cultural context is essential for accurate scientific interpretation and for acting as a check on the ethics and legality of such research,” said Halcrow.
Bernardo Arriaza, a bioarchaeologist from the University of Tarapacá in Chile and a co-author of the new study, said Nolan and his colleagues should have considered the archaeological context within which the mummy was found. It’s possible that Ata is a miscarried fetus, and from the very recent past. “This mummy reflects a sad loss for a mother in the Atacama Desert,” he said.
The authors also complain that no ethics statement or notice of an archaeological permit was included in the Genome Research paper.
“Given the fact that the mummified fetus was clearly human, the geneticists did not need to do further testing,” said Killgrove. “But more problematic than that was, once they did test and find it was human, they didn’t immediately stop and question the forensic or archaeological ethics. Whether the fetus mummy was ancient or more recent, Chile requires permits for this sort of testing. We believe that these geneticists should have involved a specialist in developmental skeletal biology from the beginning as they would not have made rookie mistakes. But we also want to use this as a cautionary tale going forward—genetics experts need to be informed about ancient and modern laws and ethics surrounding testing.”
Gizmodo reached out to both Garry Nolan and Atul Butte to get their comments and perspectives on the new International Journal of Paleopathology paper, but no response was received at the time of this article’s publication. That said, Gizmodo did receive a relevant statement from Nolan and Butte on March 29, 2018, in response to previous questions about the Chilean National Monuments Council complaints:
We affirm the need to respect the traditions of other cultures in genomic analyses. We have previously stated that we believe the skeletal remains should be returned to the country of origin and, by finding them to be human, this research supports the argument that these remains should be repatriated. This research clarifies what has been a very public and sensationalized story for a long time, and it was done out of a desire to bring some humanity to this discussion and dignity to the skeleton.
The skeleton has never been in the possession of either Stanford or UCSF, and we had nothing to do with removing the skeleton from its place of origin. The DNA and images come from remains that were not known to be human when the research began. It does not provide identifiable information about a living individual, as defined by federal regulations, and does not qualify as human subjects research, per the Federal Office of Human Research Protections. It has long been known that this skeleton was privately held in Spain, without any allegations of criminal conduct as to how it was acquired.
Speaking to the New York Times back in March, Nolan said he had no reason to believe that the mummy was obtained illegally, and that it wasn’t obvious they were dealing with a human specimen. Subsequently, his team didn’t require permission from Stanford University to study a skeleton that possibly belonged to a nonhuman primate.
We’ll update this post should we hear back from Nolan or Butte.