As longtime readers here know, I’m endlessly fascinated by the ways in which people attempt to misuse genetics to legitimize pseudoscientific ideas.
Today I’m going to write about one example which I’ve been meaning to address for some time: pseudoscientific claims about the genetic distinctiveness of the Paracas peoples. (Please note that I don’t usually show images of Native American remains on this blog, but there was no other way to illustrate the details of this issue. Under the cut is an embedded video of the unwrapping of a Paracas mummy, as well as a photo with the mummy under its wrappings.)
Many ancient societies in North and South America practiced cultural modification to the crania of their infants, resulting in distinctive skull shapes in the adult population. This practice took several different forms, as anatomist Dr. Valerie Dean O’Loughlin notes in her 2003 paper Effects of Different Kinds of Cranial Deformation on the Incidence of Wormian Bones. (p147)
Cultural cranial deformation could be intentionally induced in a variety of ways (Dingwall, 1931; Dean, 1995a). The vault could be tightly encircled by bandages, producing a cylindrical or conical head shape (e.g., in South America). Securing the skull between two boards flattened those portions of the head in direct contact with the boards (e.g., on the Northwest Coast of North America). In some cultures, the deformation may have been unintentional, as when an infant was secured on a cradleboard for a long period of time, consequently flattening the back of the head (e.g., the Southwest US)
Reasons for modifying cranium shape were varied and sometimes culture-specific (Dingwall, 1931; Topinard, 1879; Dean, 1995a). Northwest Coast, Columbian, and Peruvian cultures viewed males who had deformed skulls as more brave and powerful. Most cultures that practiced intentional molding viewed a “molded” head as a sign of high status. Often, slaves were not allowed to practice cultural cranial deformation, and so their head shape was a physical sign of their social status (e.g., Northwest Coast). In addition, culturally modified skulls were viewed as a sign of beauty, and the more marked the deformation, the more beautiful the person was regarded as being.
The Paracas peoples, who occupied the southern coast of Peru between 800-100 BCE, are among the best-known practitioners of this custom. Makers of sophisticated textiles, and the forebearers of the Nasca culture, they have long attracted the attention of fringe theorists, who attribute their cranial modifications to a different ancestry from other Native American peoples. Their elongated crania have been variously explained as aliens, a separate human species, a “hybrid race” of super-human Nephilim , and all sorts of other nonsense.
Some number of the Paracas crania, excavated by Julio Cesar Tello in the 1920s have been on display in a private museum, owned by Juan Navarro Hierro. Several years ago, tour guide Brien Foerster sent skeletal samples from some of these crania to an anonymous geneticist and received a report that they “had mtDNA with mutations unknown in any human, primate or animal known so far.” Foerster made much of these results in books and interviews, which—along with the procedures used to obtain them and the identity of the geneticist–remain unpublished. This is a classic case of science-by-press release, and Ken Fitzpatrick-Matthews has an excellent rundown of this debacle on his blog Bad Archaeology, as does Doubtful News.
Recently I’ve been hearing claims about new DNA tests on the Paracas skulls put out by L.A. Marzulli in podcast interviews promoting his book Nephilim Hybrids: Hybrids, Chimeras, & Strange Demonic Creatures. In one interview he insisted that the newest DNA tests were conducted completely legitimately and under strict anti-contamination protocols, and yet the results showed that they were Nephilim/European hybrids. I was interested, so I read his book to see exactly what they did. Their approach serves as an excellent teaching opportunity in evaluating ancient DNA research.
Evidently there were two sets of DNA tests. The first round, which is what the bloggers above discuss, was conducted some time ago by an anonymous geneticist, who Marzulli says was fired for continuing to work on the Paracas skulls after his supervisors told him to stop. The new tests, results of which Marzulli published in his new book, were performed on a culturally modified cranium from a ‘private collection in Oregon’ that someone inherited from his grandfather, who had allegedly obtained it in Peru. (This work on privately “owned” human remains, presumably without consultation and for the explicit purpose of promoting pseudoscience, is insanely unethical).
Marzulli insists that the aDNA tests were conducted by a legitimate laboratory, and included their reports in the appendix of the book. I looked up who did it, and he’s right: they’re a legit commercial ancient DNA service. Out of professional courtesy I’m not going to post their name here, because if I were in their position I would hate to be associated with this nonsense. (It’s easy enough to find out who they are, if you really want to know.) Based on their reports to him, they cautioned him extensively about their concerns regarding contamination of the sample, and he ignored those cautions to promote his own ideas.
I’m going to take you through what Marzulli claims they did to obtain the bone and hair samples in both sets of tests, and show you where they failed to take some crucial measures to prevent contamination. First, let’s take a look at his and Foerster’s original attempt to sample DNA from an individual in the private Peruvian museum. Marzulli describes it this way in his book: “The lab told us the sample may have been contaminated. However, I was there and watched the proceedings, and the hair that came off of the skull while Joe Taylor was unwrapping it was put immediately into a collection bag.” He reports that the anonymous technician who did this work recovered mt haplogroup U2e1 from the remains, and that this DNA was absolutely not contamination.
There is no discussion of the laboratory methods, so I’m unable to evaluate them (always a red flag with ancient DNA work). However, the sampling procedure is documented in this video (Warning: watching this completely unnecessary destruction of a child’s remains is difficult.) .
It’s very clear where the contamination took place. I’m going to annotate a screen capture of one frame to illustrate. (Note: This image does show part of a child’s mummy. The wrappings are intact in this frame).
As you can see from the image, the individuals attempting to sample DNA from this mummy made some attempt to cover themselves, but it’s entirely inadequate for ancient DNA work. There is exposed skin on every individual in the room, the gentleman’s beard and hair are uncovered, and at one point they start squirting water all over the mummy, claiming that because it’s distilled, it won’t introduce contamination. Wrong. All water used in ancient DNA work has to be purchased from vendors who guarantee that it’s certified DNA free. Distilled water has lots of DNA present in it. Any one of these things could have (and probably did) introduced contamination to the sample they tested.
By contrast, here is what I wear when sampling for ancient DNA analysis in the field (no human remains are visible in this image):
Some exposure of the face is unavoidable, but is kept to a minimum with a head covering that also hides the ears, forehead, and hair. I don’t stick my face directly over the tissue I’m sampling, I don’t allow any portion of my hands, wrists, or arms to go uncovered, and I certainly don’t squirt water on the sample. Once collected, the sample (bone) is immediately put into a sealed, sterile bag, and not opened again until it’s inside the sterile ancient DNA isolation laboratory. Then it’s thoroughly bleached and UV irradiated to remove surface contamination. (Also, please note that this sampling and analysis was done with the permission of the descendant community).
In their second attempt to retrieve Nephilim DNA from individuals from culturally modified crania—this time, from the skull in someone’s private collection– Marzulli claims that they sampled the remains wearing a full body suit, face mask, sleeves, gloves, and shoe coverings, and that “enabled us to reduce contamination, however, this artifact had been handled by numerous people over the years, and we have come to understand that just breathing on it can contaminate it.” Note that although he claims they have come to understand this, he never admits that contamination was likely responsible for the results of the first test of the child’s mummy.
There are ways to mitigate surface contamination, but based on his description of how they sampled the cranium, he doesn’t employ them. Using a Dremmel tool, he says they drilled into the skull, “cleaned the area” with compressed air, changed drill bits and then drilled out powdered bone from the skull. Blowing compressed air into the hole will do exactly the same thing that squirting water does: introduce DNA. No bleach or UV were used to decontaminate either the tools used to collect the bone sample, nor the sample itself. Also, photographs of the cranium (which I’m not going to show, as per my policy of minimizing the use of images of indigenous human remains) show it to be extremely shiny, as if it has some kind of varnish on them. If that’s the case, there are likely layers of contaminating DNA deposited on the surface of that bone, effectively sealed in by that varnish.
The technician who did the DNA extraction and work on the samples notes the same thing in his or her report (included in Marzulli’s book)
Without physically seeing the item itself, I can only guess that the skull was heavily handled over the years. Therefore any surface of the skull that is exposed to the environment could be contaminated. If the powder from the interior of the skull was just scraped off the interior surface, we could just be looking at surface contamination even though it was from inside the skull cavity. There is also no way of knowing how much contaminant DNA can leech into a sample from the surface. It is also possible that the tools used to remove the powder were not sterile and contained exogenous (outside the sample) DNA.
Finally—and very importantly—it is standard for ancient DNA researchers to sequence their own DNA, and that of the archaeologists, biological anthropologists, and anyone else who may have handled the remains, in order to rule out that any results might be inadvertent contamination from them. Marzulli, Foerster, and others involved have never done that. This is important because the laboratory detected two different mitochondrial haplogroups in the samples Marzulli sent: T2b, and B4. It’s impossible to know whether either haplogroup was introduced by the persons involved in sampling. As a reviewer I wouldn’t accept either result as endogenous DNA: it would need to be redone under proper conditions, verified by at least two independent extractions, and include comparative sequences from the individuals sampling the DNA to ensure that the sequences recovered weren’t from them.
That being said, Marzulli’s response to the results provided to him was fascinating. He notes that “The bottom line is that mitochondrial DNA was found from the powder and it was haplogroup T2b,” which is not an autochthonous Native American maternal lineage. This result fits with his mythology that the Paracas people “arrived roughly 3,500 years ago, which fits the timeline of the diaspora from the Levant of Promised Land perfectly.”
Marzulli completely ignored the finding of haplogroup B, which is quite common in South America, presumably because it would fit with the archaeological interpretation that these individuals are indigenous to the region.He wants to believe that the Paracas individuals are genetically different, because that is required by his worldview:
I believe the Nephilim tribes fled, and some went north into Europe while others traveled the Mediterranean Sea to the Atlantic; and then, as Thor Heyerdahl proved in his bestselling book Ra, all one needed to do was set sail, and the trade winds would push you to the island of Barbados in the ‘New World’
He concludes by saying: “People will complain that the sample was contaminated. They’ll tell us the results were skewed. They’ll come up with every excuse imaginable in order to keep the evidence from the public.”
Yes, that’s exactly what we’re saying. All the samples taken were almost certainly contaminated, as I’ve shown you in some detail. There are tried and true ways of preventing and detecting contamination, but they were not employed here.
It’s perhaps also noteworthy that a very large section of his new book is devoted to discussing the “demon fairy” discovered in Mexico*….which he has just admitted was a fraud. This collapse of his evidence doesn’t seem to have deterred him from his belief in the reality of Nephilim. Nor do I expect that my discussion here will deter him.
I took a long time to write this post, because I kept wondering if it would do more harm than good to bring attention to Marzulli and Foerster’s outrageous claims. But ultimately I decided that this was a good example to use in teaching some basic concepts in ancient DNA research. I hope that interested readers will be better equipped to think critically about ancient DNA claims in the future. Ancient DNA is a useful tool, but only when it’s employed under the most stringent conditions. You simply can’t be sloppy with these methods, or you’ll end up with meaningless results.
*I swear I’m not making this up. He really talks about it as if it’s important evidence of his Nephilim idea. Demon. Fairy.
For further reading:
How to tell if an ancient DNA study is legitimate: https://violentmetaphors.com/2014/02/07/how-to-tell-if-an-ancient-dna-study-is-legit/
Jason Colavito’s blog discusses Marzulli’s claims in several posts: http://www.jasoncolavito.com/blog
Andy White also has several good discussions of Nephilim hybrid claims: http://www.andywhiteanthropology.com/blog/category/nephilim
Robert Martin has a great piece on cranial modifications here: https://www.psychologytoday.com/blog/how-we-do-it/201606/honey-i-squished-the-kids-heads
Finally, I’m actually giving a talk about genetic mythologies, including Nephilim claims, at this year’s Skepticon on November 12th in case you’re interested in hearing more.