Bigfoot Yeti and the Last Neanderthal Page 2
No testimony is sufficient to establish a miracle, unless the testimony itself be of such kind that its falsehood would be more miraculous than the fact which it endeavours to establish.
In other words, the proof would need to be so convincing that for it not to prove the miracle would itself be miraculous. That seemed like a good standard to aim for in my examination of the yeti and Bigfoot evidence. If I had doubts, then I only had to imagine myself presenting each piece of evidence to David Hume for his opinion on its value.
Hume also clearly recognised in his essay that rationality and human nature do not always agree when he wrote:
With what greediness are the miraculous accounts of travellers received, their descriptions of sea and land monsters, their relations of wonderful adventures, strange men and uncouth manners? . . . The avidum genus auricularum, the gazing populace, receives greedily without examination whatever soothes superstition and promotes wonder.
He could have been writing about yetis. I see close similarities between the level of proof he insists upon for miracles, given the fanciful inclinations of human nature ranged against reason, and what most of us would need before we believed in yetis or sasquatch or any other anomalous primate. A live capture, a thoroughly investigated body, possibly even a good-quality, unadulterated film or photograph might be enough. But in their absence is there anything else capable of providing such high levels of proof? It is my belief that DNA, if used properly, does have that capability. It cannot be forged, so far as I know, and with the results independently verified, would, I am fairly certain, satisfy even the great philosopher.
This adventure was not my first excursion into the world of anomalous primates. In 2000, I had received three hair samples in my laboratory from the remote Himalayan kingdom of Bhutan. They were from the migoi, the Bhutanese equivalent of the yeti. I had been asked to identify the migoi hairs using modern DNA analysis, in much the same way that I had used these techniques for many years to explore the human past.
The migoi hairs did not surrender their secrets easily, but eventually two of them were identified as known species of bear. The third remained a mystery. There was DNA, but I could not identify the creature it had come from. The migoi project was a sideline, an amusing distraction from the main work of the laboratory. The unused migoi samples joined the thousands of others in the freezer and we carried on with our mainstream research into human origins. But I never completely forgot about the migoi.
Ten years later, two scientific developments caused the migoi to bubble up into my thoughts once again. The first was purely technical. Our main difficulty in getting DNA from the migoi hairs had been that there was very little of it in the first place. Only the hair follicle, the root, contained enough DNA for analysis using the lab protocols of the time. Between then and now the protocols have improved a lot, so that these days an intact follicle is no longer necessary, and I found that I could get a very good DNA signal from a single hair with no root attached. This proved to be the technical breakthrough that made this current project feasible.
The second development was more intellectual than technical and arose from the surprising conclusion of a paper published in the journal Science in 2010. This article contained details of the DNA sequence from the fossilised remains of another human species, a Neanderthal, widely thought to be extinct. By comparing the Neanderthal DNA sequence with that of modern humans the researchers had concluded that the genomes of Europeans and Asians, but not Africans, contain a small amount of Neanderthal DNA. The explanation offered was that the ancestors of Europeans and Asians had interbred with Neanderthals. This conclusion supplied an intellectual focus for examining the notion, popular among cryptozoologists, that small groups of Neanderthals had somehow managed to survive in remote forests and mountains until recent times, or maybe even to the present day.
While scarcely guaranteeing success, these two developments – the technical ability to identify the species origin of any hair sample from a single shaft, coupled with the strong intellectual case for interbreeding – persuaded me that I now had the tools to do some proper science in what most scientists, for reasons we will explore later, regard as a taboo field. I certainly would not have contemplated getting involved in this work any earlier in my career. Now I am less concerned about what other people think, and have the freedom to explore avenues of research that would have been foolish when I was younger.
Let me be completely clear. I deliberately did not set out to find the yeti. Instead I set a goal to locate and analyse as many hair samples as I was able that had been attributed to anomalous primates, in particular to the Himalayan yeti, the Bigfoot/sasquatch of North America (I use the term interchangeably throughout), the Russian almasty and the diminutive orang-pendek of Sumatra.
In doing so, I found myself entering a strange world of mystery and sensationalism, fraud and obsession and even, at times, the supernatural. I felt safe in doing so only because I was protected by the ruthless rigour of genetic analysis. I was ready to listen to the stories of enthusiasts and eccentrics, liars and lunatics, without having to form an opinion. The only opinion that mattered belonged to the DNA. I certainly met some extraordinary characters along the way, many of whom you will meet later on – people who have spent their lives looking for these creatures and are utterly convinced of their existence. Any doubt is tantamount to heresy and at least one website devoted to Bigfoot has adopted this quotation from the American economist and social theorist Stuart Chase as their mantra.2
For those who believe, no proof is necessary.
For those who don't believe, no proof is possible.
The distinction between this and Hume's rationalism could not be more stark.
Cryptozoologists are the unrepentant advocates for one face of the yeti enigma, with plenty of ‘evidence’ to back their claims. On the other are the all too obvious holes in their argument and the glaring absence of a single piece of evidence that is universally convincing and accepted. This is the enigma I set out to explore.
3
The Last Neanderthal
It could not be described as an extraordinary death. Just an old man dying alone. And yet it was at that moment that we lost our last chance of knowing, really knowing, our nearest human relative. For this man was the last of a dying species, much closer in both genetic and cultural terms than any strained comparison with the chimpanzee, gorilla or orang-utan could ever be. Though he did not know it, this man was the last Neanderthal. His death marked the moment that he, and with him his entire species, became extinct. From that moment on we, Homo sapiens, became the only human species on the planet.
The location for this unannounced extinction was a cave high up on a limestone bluff above the Mediterranean in what is now southern Spain, not far from the modern city of Malaga. It happened thirty thousand years ago, ten thousand years before the coldest phase of the last Ice Age. His ancestors had ruled a continent for over a quarter of a million years. From Britain in the West to Iran in the East, they had hunted wild game and brought up their children. They had survived conditions much colder than today, more like Greenland than anything on continental Europe. To cope with the severe conditions Neanderthals had evolved to become compact, hairy and immensely strong. For all but the last forty-five thousand years they had the continent to themselves, the only human species.
But then a new form of human appeared from the Middle East; much lighter-boned, almost lithe by comparison. They had great difficulty in coping with conditions in Europe that were so very different from the plains of East Africa where they had evolved a hundred thousand years or more before. The new arrivals were our ancestors, Homo sapiens, and they would eventually drive the Neanderthals to extinction. The process was not deliberate, and for twenty thousand years the two human species lived side by side. But slowly the Neanderthals were confined to less and less productive territories. They had to spend longer and longer hunting to catch less and less. They seemed for some reason u
nable to adopt the superior weapons technology of their cousins. Weakened by hunger, most died from starvation rather than from any violent confrontation with our ancestors.
And that is what happened to the last Neanderthal. He was a man of about thirty years, born into a small group of five – his parents, an elder brother and two sisters. Apart from other members of the family, he did not see another Neanderthal during his entire life, and neither had his parents, who were actually brother and sister. Weakened by the genetic effects of inbreeding, his own sisters died young and his brother had perished while hunting, a common enough occurrence. His parents passed away when he was in his twenties. He was alone.
Unable to join up with others to form a hunting party, he scraped a living by scavenging the carcasses left behind by predators, including the relative newcomers, our own Homo sapiens ancestors. He took trouble to avoid them at a kill, keeping well out of sight behind whatever cover he could find until they had taken what they wanted and returned to camp. He also faced competition from other scavengers. Foxes and vultures were easily coped with, but when he heard the whinnying cry of a hyena, he hastily withdrew. The hyenas, fast, intelligent and with their fearsome bone-crushing jaws, would have killed him without a second thought. He managed to maintain this lonely existence for ten years. He thought of leaving to search for others of his kind, but he also knew that it would be risky to try to survive in unfamiliar territory. What he did not know is that his search would have been entirely futile. There were no other Neanderthals. He was the last.
Every year he grew weaker, not least because hunger drove him to scavenge even long-dead cadavers, after which he was often violently sick. Evolution had not prepared him for this life, unlike the vulture and the hyena who could eat rotting flesh without suffering any ill effects. Eventually he became too weak to leave his rock shelter, a hundred feet up a sea cliff and only accessible by a difficult climb from the shore. Emaciated and unable to move, it was here that he died. Slipping into unconsciousness his eyes closed for the final time on the blue Mediterranean with the afternoon sun shimmering on the ruffled surface of the sea.
I wrote this rather fanciful account of the final demise of the Neanderthals in 2005, when I had been contemplating writing a book on the topic. It comes from the prevailing opinion at the time, that after sharing Europe and parts of western Asia with our Homo sapiens ancestors for twenty millennia, Neanderthals became extinct. And when a species becomes extinct, one of them has to be the last survivor. I placed him in southern Spain because it is there, in Zaffaraya Cave not far from Malaga, that the youngest undisputed remains, a mandible, or lower jaw, of a Neanderthal was excavated in 1983. The jaw was dated to 29,550 years BP, the youngest found so far. (Before Present is the standard archaeological term for times past, measured against 1 January 1950.)
In the few years since I wrote those words, a lot has changed. Neanderthals had clearly travelled further into Asia than Iran, with remains found twelve hundred miles further east in Okladnikov Cave among the Altai Mountains of southern Siberia in 2007. Yet more human species have been discovered, most notably at Denisova Cave, also in southern Siberia. What has also changed is what we have found out from genetics. We already knew a great deal from the study of mitochondrial DNA. This small piece of DNA has been a favourite of mine since I and my research team were the first to recover genetic material from ancient human bones in the late 1980s. In ways I will explain in more detail later, mitochondrial DNA has led the way in all explorations of genetic ancestry, from the very recent to the very remote. Its unique pattern of inheritance, being passed down only through the maternal line, means that it traces our matrilineal genealogy, from mother to mother, virtually unchanged from the present day back for thousands of years into the deep past. I have used mitochondrial DNA extensively in my research, both from ancient human fossils and living people, to trace the origins of, among others, the Polynesians, early Europeans, the British and most recently, the Americans.
As far as our genetic relationship to the Neanderthals is concerned, by 2005 we had the genetic fingerprints of mitochondrial DNA recovered from a handful of Neanderthal fossils. These showed that although Neanderthals were certainly related to Homo sapiens, they had not been our direct ancestors, which many had once thought. Five years later, the arduous business of sequencing the Neanderthal nuclear genome had been completed. To everyone's surprise this work came to the conclusion that, in Europe and Asia but not Africa, a small but significant proportion of our DNA had been directly inherited from Neanderthal ancestors through interbreeding.
In a small way, the Neanderthals live on in many of us, but I still wondered about their practical extinction. Largely insulated from our own mortality, it is hard for most of us to imagine that whole species can disappear. But, of course, they can and do and have done since the dawn of time. So the extinction of a human species is not in the least remarkable, yet it has necessarily to be accompanied by a final death of the sort I imagined happening in Zaffaraya Cave. Somewhere, at some point, there had to be a last Neanderthal.
I never did write that book. I wondered, only very vaguely, whether I could ever find a modern human with a Neanderthal mitochondrial DNA, which would offer instant proof that they had bred with our ancestors. The closest I got was a very unusual skull that I came across, entirely by chance, in the museum of the Royal College of Physicians in Edinburgh. In 2008, my son Richard was studying for his A-Levels at the Edinburgh Academy and was doing an art project involving anatomical drawings. I visited the museum to look out some suitable material for his project. During this visit, I got talking to the curator Andrew Connell, who told me about the ‘Neanderthaloid’ skull.
It had formed part of the collection of the late Dr David Greig. He had an interest in abnormal skulls, many of which were displayed in the museum. The ‘Neanderthaloid’ skull was one of these. Greig went as far as writing a monograph on it which the College published in 1933.1 Andrew Connell got a copy down from the shelf. It contained some masterly drawings of the skull, whose accuracy was confirmed when I examined the skull itself. However, what the monograph does not contain are any details of the skull's provenance or how it came to be in Dr Greig's collection. Andrew Connell thought this highly unusual for the otherwise meticulous Greig and suspected this lack of detail masked an unsavoury provenance of some kind. Edinburgh was after all the home of the notorious grave-robbers turned murderers Burke and Hare and of their patron Dr Robert Knox, who received the bodies for dissection. It is entirely my speculation that the ‘Neanderthaloid Skull’ might have been added to the collection in this way, but the silence about its origins was certainly extremely unusual for Greig.
When I had a close look at the skull the brow ridges were remarkably prominent – hence its labelling as ‘Neanderthaloid’. But other parts of the face were less like a Neanderthal. For one, the cheeks were not pushed forward and there was a fairly prominent chin. There were numerous bony lesions on the surface indicative of pathology, possibly tuberculosis. Greig's monograph, which contains a very detailed description of the skull, does not come to any conclusion on the significance of the brow ridges or the surface irregularities. The skull had been cut in half to reveal the inner cranium and the section revealed a thick rim of parietal bone at the level of the cut. There were four teeth, none of them in good condition.
The first thing I wanted to know was the age of the skull. Had it been over thirty thousand years old it probably was a genuine Neanderthal, interesting but not unique. But if it were much younger then it would have been more interesting, a surviving Neanderthal or a hybrid perhaps. It looked quite modern, but to be sure I needed to carbon-date a sample.
After considering my application, the College kindly allowed me to drill into the parietal bone and I sent this off to my colleagues in Oxford for dating. It certainly did turn out to be modern, with a radiocarbon date of only 270 years. To see if it was from a surviving Neanderthal I drilled out another section and sent
that to Adelaide for DNA extraction and mitochondrial DNA sequencing. The extraction was successful and the sequence was a good one. It was not Neanderthal however, but sub-Saharan African.
I discussed the results from the Neanderthaloid skull with Prof. Chris Stringer from the Natural History Museum in London. Chris is the foremost expert on Neanderthal fossils and someone with whom I have worked on other projects in the past. We talked about the feasibility of finding Neanderthal DNA that had survived into modern times and wondered where best to search for it. Finding Neanderthal mitochondrial DNA in just one living Homo sapiens would be sure proof of interbreeding between the two human species. Chris suggested three locations: southern Spain around Zaffaraya but also the Caucasus region and the Altai Mountains of Siberia. The youngest Neanderthal was found in Spain and the other regions are known hotspots for Neanderthal fossils and ones where Chris thought I would also have the best chance of finding a living person carrying the mitochondrial DNA of a Neanderthal. I carried on with other work, though still keeping an eye open for people with the characteristic features of the Neanderthal: the flat forehead, prominent eyebrow ridges, receding chin and so forth. I saw plenty of candidates, but none so remarkable as in Paris, at the Muséee de l'Homme.
I had been in Paris for a few days on business and decided to call in to the museum, a short way across the Seine from the Eiffel Tower. There was no particular reason for the visit other than I had not been there for a long time. The Musée de l'Homme is the Parisian equivalent of the Natural History Museum in London, but with a focus on human evolution, as its name suggests. On the first floor of the museum is a diorama of life-size models of our earliest ‘ancestors’ starting from the distinctly ape-like Australopithecines, through more advanced forms to modern Homo sapiens. The models complement the museum's fabulous collection of human fossils displayed in glass cabinets nearby. It was a Saturday afternoon, and the museum was full of children scampering to and fro, occasionally looking at the displays though more often just running the length of the hall and back again. As I worked my way along the diorama through millions of years of evolution, I eventually came to the penultimate model in the series, the sturdy figure of a Neanderthal.