So, if we want to be able to recover this very ancient and degraded material, we have to get rid of all of that extraneous D. So, we conduct this work in special laboratories that have highly filtered air; we have ultraviolet radiation built into the ceiling to sterilize the room in between uses; and we wear these Tyvek suits, which help keep our D. Most people, when they see them, they're used to seeing them in context of people in epidemics trying to protect themselves from disease.
We wear them for the reverse reason. We're trying to protect our samples from our D. We clean the teeth with bleach to remove and destroy any D. In a way, it's almost like getting a very belated dental cleaning. We use an abrasive tool to remove the outer layer, to really scrape off these contaminants. And then we use ultraviolet radiation that causes damage in any D. We can then liberate the D. Tina's meticulous cleaning methods pay off. She's found some of the best preserved ancient D. That is extraordinary and likely resulted because the region is so cold and dry.
One hundred milligrams of tooth material, about the size of a pea, is all that's needed to fully sequence a single human genome, the genetic blueprint, unique to each of us, that contains traces of our ancestors' D. We can take these pieces of D. Geneticists can find out clues to our origins by looking closely at small variations in our D. Population geneticist Anna Di Rienzo found that the genomes of all the samples collected in Mustang, even those from different caves, are very similar. One of the major findings of our study is that the gene pool of these populations hasn't changed in a major way over the period of time that we have sampled, which is roughly 3, years.
After comparing the samples from the cave people with each other, Anna then compared the genomes with different present day populations around the world. She's looking at small sections of their D. We can ask with this analysis, "Who are the populations that are closest, genetically, to our samples? Surprisingly, there was no match with people from any part of India today.
Although their burial customs differed from one group to another, and some had artifacts from India, and lived at different times, genetically, all the cave people were very close. The genetics were incredibly stable through time. This was fascinating to us, because we saw big changes, for example, between the Mebrak and the Samdzong period.
We suddenly see de-fleshing. That's a new thing, that's a religious change; and yet we don't see any change in the underlying genetics of the population. But researchers have spotted one genetic change, specific to high-altitude peoples of the Himalaya. It's an ancient mutation, or gene variation, a change in the order of the chemical bases, the As, Ts, Cs and Gs that make up the gene.
The variant prevents people from getting sick at high altitude, where the available oxygen is low. There are a few places in the genome, a few traits, in which we have experienced very recent evolution. So, one of these would be the adaptation to high altitude. There's only a handful of these genes that are very, very recently undergoing selection, and this is one of them. Most of the Himalayan people that live here now have this variant. The team wants to know if the ancient people buried in the caves also had this mutated version of the gene.
To gather even more D. Although it's only 30 miles away, as the crow flies, due east, getting there takes three days of driving and another three days on foot. It'll take 10 hours to hike to 12, feet in a day, a rapid 4,foot gain in elevation, not enough time for most people to acclimatize, or adjust, to the altitude. You'll see, as we're walking uphill, steadily gaining elevation, we have to breathe a lot heavier, might just feel like our performance is really down.
There's really nobody around. PBS is a c 3 not-for-profit organization. What we really needed was D. They'll analyze each one to piece together the story of the unknown people. A group went in much, much later, and they applied ocher to the remains.
Now, a lot of the locals don't really feel that, because they have that special makeup in their D. Meanwhile, we're out of breath. We're definitely feeling a lack of performance. We might feel like we have a little bit of a headache, a little dizziness. There's about 35 percent less oxygen available here than at sea level, so the team keeps track of how much oxygen is getting into their bloodstream, as their bodies adapt. We're at Meta, which is at about 11, feet, and we're just going to be checking the level of oxygen concentration in the bloodstream with a pulse oximeter.
The lower number is the pulse rate and the upper number is the percentage of oxygen that's being carried by the blood. When we breathe, oxygen enters our bloodstream and provides our cells the fuel they need to carry out their jobs. At sea level, a healthy person should have at least 95 percent oxygen saturating their blood cells. But at 12, feet, lowlanders who first arrive will only have between 80 and 90 percent. There is about an 82 percent carrying capacity of O2, percentage of oxygen in the bloodstream, currently. And their pulse is at about , These are fairly common numbers, actually, for arrival at altitude.
If Mark were at sea level, 82 percent would be a low blood oxygen saturation, called hypoxia, and he'd be given bottled oxygen to breathe, but at altitude this figure is normal. In contrast, Himalayan people can tolerate low levels of oxygen, thanks to a genetic trait. Somebody who lives at altitude that's got the appropriate genetic adaptations, I'd expect their pulse rate to be lower. I'd also expect their oxygen saturation to be significantly higher than folks like me.
I guess we'll test that now. I was born in the Everest region, which is the elevation about 12, feet. My expectation is, is that Temba will have a relatively low pulse rate, and he'll also have a relatively high oxygen saturation in his blood, because he's adapted to high-elevation life, genetically. Your saturation is what? I can't see it very well. And his pulse rate is You know, pretty typical for folks that are adapted to this kind of life.
If most of the people living here today have this genetic variant, the question is when and where did this adaptation begin to appear? The team moves ever-higher, into the cold and arid alpine zone at 13, feet. It's a wonder people came to settle here at all. The villages are abandoned, as locals have gone to higher pastures for foraging. Life is hard here, which is why the Himalayas were settled so late. If you look at the pattern of human migration over the last 2,, years, mountains are one of the last places on the planet to, in fact, be occupied.
Polar extremes, like around the Arctic Circle, come somewhat earlier, as well. Mountains come somewhat later. These are difficult places for people to live. They've reached their destination of Kyang. The village feels like a ghost town. There's really nobody around.
I walked through, just trying to talk with some people, but it didn't look like, I mean, there were a few donkey people, just around the corner, but they left about 15, 20 minutes ago. These are the same pastures the early inhabitants used for their animals, thousands of years ago. Somebody lived here some long time ago, built the site and buried their dead somewhere around here, on these relatively fertile pieces of ground, surrounded by these incredible vertical environments.
We will have to find out what the dates are and if there are any associated artifacts that give us a sense of what this group of people might be related to, because, right now, they are essentially unknown to us, except for the fact that they exist. About vertical feet above the village is the naturally occurring cave, with manmade walls stacked above it.
It's just that it's exposed, and there's a lot of loose rock stacked up on the ledges. If you grab the wrong handhold or foothold, you could send a big rock down, or you could fall. Pete free-climbs the large crack leading deep into the cave. He'll place an anchor above him, for a safety rope if he falls.
Going up into the cleft and way back into the dark, wearing a respirator mask and a headlamp, it can be very narrow. I can certainly get very claustrophobic moving in there. It's very dusty inside. There's a lot of remains from birds and bats and every manner of rodent in there. You're just inching your way up through this crevice, and then you enter this very spacious bone room. It was very much crypt-like. I have a couple of jaws here, couple of femora, and then a few other human pieces, a piece of wood that's pretty interesting, that are all in a bag, right here, we'll collect on the way down.
The climb is too technical for the scientists to get inside, so, Pete maps out sections of the cave on a grid, and all bones and artifacts are bagged according to their location. The process with the grid that we're lining out is really just to try to give the archaeologists an idea of where, in the cave, these materials were actually taken from. The original burials have been disturbed, most likely by looters looking for valuable funerary goods. There's a real scattering of materials.
It looks like someone had actually been doing some digging, right down in this area, to my left. So, we're looking at a context that's more disturbed than I had anticipated. The presence of animal bones suggests they were sacrificed to bury with their human owners. This is a very common pattern in this part of the world is to inter the dead with domesticated animals of one kind or another. Here in Kyang, the only ones that we've seen so far are sheep or goat. If you find animals in a grave, like that, there's got to be a reason for it. It's most likely that the animals were sacrificed and placed with the dead person, for one of two reasons: It's definitely been imprinted on there, somehow.
I bet if we wet it in water,…. It's a simple bamboo stick, but the woven pattern on it suggests it was once part of a basket. Later, carbon dating reveals the people of Kyang lived around B. Their artifacts appear to be locally made, indicating the people were self-sufficient and lived off the land. The bamboo and wood could've come from nearby. This is a very nice, um, wooden bowl, soft wood. It has a really lovely little base on it that's been made, and it imitates a bowl that's been made on a wheel.
So, it's been carved to look like that. Jacqueline determines 23 people were buried in the Kyang cave, with no cut-marks, and the presence of flesh on the joints suggests they were buried whole, but the ages of the dead are surprising. Several of these individuals are younger than Several of the adult remains are also younger adults, so, below the age of 30 to 35, and that suggests that people did die of something that shortened their lives—could be starvation, could be an infectious disease—that, you know, moved really rapidly.
An enigmatic object found in the cave hints at ritual practices that may be connected to these premature deaths. One of the most interesting things we found during this work here at Kyang is this special stick. You can see it's well-carved. It's thin at the bottom, widens out. Clearly it's been meant to either be put in the earth or maybe in a socket of some kind.
The first thing that jumps out, when you look at this under the microscope that we have here in the field, is those are little tiny pebbles that have been placed inside little tiny divots. And the divots are holding, um, glue, some kind of cement that hold these things in place. But if you look at this image, it's the image of a person. What I really think this person is doing is holding something we found in the archaeological site, what I've been calling "fire sticks. They might be four or five inches long, and usually one end is burned.
You can see the wavy or sinuous line, which I would interpret as smoke coming out of the end of that fire stick. Cultural artifacts open a window on a people's long-vanished beliefs. The humanoid figure on the stick is so unusual, Mark travels to France, to see if anthropologist, Charles Ramble, can make sense of it.
This is not just discoloration from water or something? That's actually…what they've done to highlight, they've ground up some dark stone into very fine particles and then literally pushed it into the outline of this, to kind of emphasize and bring out the contrast. Charles has recently discovered an ancient text that describes a death ritual using sticks called "firebrands," much like the ones Mark found. Tibetans believed that people died because their souls were taken away by death demons.
And these are known variously as "shi" or as "shay. And rituals had to be performed afterwards, in order to separate the soul from the demons who had taken it. Reading from text I am Taklamembar, and this is how the vampire-killing firebrand, the emanation of my mind, came into being. The demon of bad death among males was killed with the firebrands.
The demoness of bad death among women was killed with the firebrands. There is one text: These firebrands, in this text, are being used as a means of killing vampires, and vampires are the agents that are responsible for death. They are serial killers. So, if people of a certain age, between 20 and 30, die in a series, that's the effect of vampires. So, the vampires are something that steal vitality and, eventually, life.
And they latch themselves onto a family, and they will continue to affect that family until they are got rid of. This may explain why the fire stick was found in the Kyang cave with young adults who died prematurely. It's unusual that we can find textual evidence to support archaeological evidence. Reading from text The killing of vampires with the firebrand is over. May there be good fortune, good luck, blessings and virtue. Stakes of this sort are very ancient. They've been found in many parts of central Tibet and also at the foot of the Great Wall.
And they date back to the third century B. The discovery of stick effigies at the foot of China's Great Wall is another piece of evidence confirming these people could've come from there. An important feature of the study is that it provides ancient D. We can see how the data changes over time. And this is what we call watching evolution in action. Anna finds that all of the people buried in the caves have the high-altitude adaptation.
But the study of their D. The earliest of the cave people have the first genetic variant, but the most recent burials, the Samdzong people, acquired a second variant. Both variants are seen in the people of the region today. In , the tiny pinky bone of an extinct human ancestor was discovered in a cave in the Altai Mountains of Siberia, called Denisova. The 41,year-old pinky bone had just enough D. The individual was female, young and had that second adaptation. This Denisovan population that had a relatively wide geographic distribution in Asia, maybe they already had adapted to high altitude.
That's part of the history that we would like to dissect. At some point in pre-history, Homo sapiens, our modern human species, must have mated with the now-extinct Denisovans. It's likely the only way humans could have obtained the second high-altitude gene adaptation. We don't know exactly where the encounter between this Denisovan-like population and the modern human populations occurred.
It's possible that this mutation was present in the Denisovan-like population but was not advantageous, yet after the mixing between these two, and the modern human population moved to high altitude, it became advantageous. The finding was very exciting. It's telling us something more than just the fact that modern humans and Denisovans mixed, but, also, that Denisovans gave modern humans an allele that allowed them to conquer this so-called "Third Pole," and to adapt to these very harsh conditions of high altitude and hypoxia. Genetics and the study of ancient D.
This new ability that we have to actually sequence ancient genomes is teaching us so much we didn't know about human history and pre-history. So, already, we're rewriting the storybook of humanity. We're definitely still evolving. The point at which we stop evolving is when we're an extinct species; that's the end of evolution, right there. Those slight changes give us the ability to adapt to changing environmental conditions.
Here in the Himalayas, we can trace how we evolve over time. That the people here can thrive at altitude shows just how adaptable we, as a species, can be. We now know more about the early cave peoples' beliefs and how they endured one of the toughest places on Earth. And the knowledge gained by recovering ancient D. Watch Online Full program available Soon. How do corpses become mummies?
See how natural forces and artificial techniques preserve bodies through the ages. What is a mummy? Get a primer on mummies worldwide—from ancient Egypt to the Incan Andes to the peat bogs of Eu How did ancient Egyptians prepare a body for burial?
Discover Secrets of The Himalaya - Kindle edition by Mahayogi Pilot Baba, Ravindra Sehgal. Download it once and read it on your Kindle device, PC, phones or. 'Himalaya Unveils Mystery'. The original script is has been compiled in two volumes. These are 'Unveils Mystery of Himalaya' as volume I and 'Discover Secrets.
Witness the elaborate process of mummification in this slide show. A new forensic investigation of a 5,year-old mummy reconstructs his death and reveals an ancient way of life. PBS is a c 3 not-for-profit organization. Littered among the bones are stunning artifacts. The part I hate the most is you make a dumb move, you're done.
Top technical climbers are needed to reach the early human remains.
Somehow, the ancient people adapted to the Himalayan extremes, but life wasn't easy. People are people, there's always conflict and violence. Relics are unearthed from sacred death rituals. Pete has assembled a team of scientists and the world's best climbers. Is that pretty much above the big portal, as far as you can tell? There are over 10, caves here, and they've targeted the most promising.
The climbers are working with archaeologist, Mark Aldenderfer. The task is enormous, made ever more difficult by the unforgiving altitude. The locals are skillful traders. Their cash crop is goats. Going up a pretty big pass. Pete will first map the bones and artifacts, to provide context. There are 10 cave tombs, in all.
Does it ever get easier? It's a foot cliff, with a foot drop into the uppermost caves. Mark believes the caves were carved out intentionally, to entomb the dead. Now, the hard part begins, doing the lab work. Later, carbon dating of the remains will show the people lived between and A. But there's something unusual about how the ancient people treated their dead. That's a cut mark. Yet, an artifact found in one of the Samdzong tombs challenges this notion. A Buddha in a cave with human bones seems out of place. This could be the earliest Buddhist relic ever found in the high Himalaya.
A forensic investigation of Samdzong's artifacts commences, to determine their possible origins.
One cave had a coffin-like bed inside. Two mysterious pieces of metal were also found in the cave. I really don't want to flatten it too much. So, that look like a nose? That kind of looks like an eye.
We have two masks. They are death masks. And there's even a third one. This guy's got more color. He found there are two layers of precious metals in the masks. The technique that they used was hammer welding. Pinholes can be detected on the outer rim of the mask. They need more evidence. We can be quite sure that we are dealing with Chinese silk.