"Mystery of the First Americans"

PBS Airdate: February 15, 2000
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NARRATOR: Walking along the banks of the Columbia River near Kennewick, Washington, two men made a grim discovery. Treating the case as a possible homicide, the police called in forensic investigator Jim Chatters. At the riverbank, he searched for the rest of the skeleton.

JAMES CHATTERS: Most of the large bones were visible. The big parts of the pelvis were there, there were parts of both thigh bones, pieces of both arms just lying right on the surface of the mud.

NARRATOR: Now his job was to provide the police with a description of the victim. Judging from the size of the bones and the wear on the teeth, it appeared to be a male about 45 years old. To determine race, he examined the skull.

JAMES CHATTERS: Well, the first thing I saw when I looked at that skull was a long narrow head with fairly prominent brow ridges and an extensive nose. This, to me, almost automatically said, OK, I'm probably dealing with a Caucasian. And in looking at this individual, if he's got characteristics that are similar to those of Europeans, then I'm thinking he's a fairly recent person.

NARRATOR: It seemed like a straightforward case. But then he found something that didn't fit - a gray object embedded in the hip.

JAMES CHATTERS: It was the color of gray stone or corroded lead. I took it in and had it x-rayed. Well, the x-rays couldn't see it, which meant it clearly was not lead or any other metal, and we CAT scanned it the next day and found it was the base of a rather large spear point. That made the story rather different.

NARRATOR: Why was a Stone Age weapon lodged in the hip of an apparently modern skeleton? Chatters sent a small piece of bone out to be dated at a radio carbon lab. A week later the results were back. The Kennewick Man was almost 9,000 years old.

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NARRATOR: An archaeologist as well as a forensic investigator, Jim Chatters knew that the 9,000-year-old Kennewick Man was a rare find. Only a handful of skeletons this old had ever been found in North America, and this one was in excellent condition. Chatters began to document the pathologies in the bones.

JAMES CHATTERS: This fellow told more of a story than most people I've ever dealt with. I mean, he not only had the spear point stuck in him - and it was healed there, he'd had it for quite a long time - but he had a whole series of other injuries too. If you sort of start from his youth, he broke his left elbow and appears to have gotten an infection or some serious bone damage. He had his chest crushed with a massive blunt blow, breaking the ribs off on either side and leaving them separate. That's an often fatal wound. It healed. He has a little skull fracture on the front left side, the kind that's consistent with being struck by a right-handed person wielding a club, and that had healed. In a few words, the man led a perilous existence.

NARRATOR: But the most striking thing about the Kennewick Man was the shape of his face and skull. In a skeleton this old Chatters would have expected to see the wide, flaring cheekbones and rounder skull of an American Indian. But Kennewick Man had a long cranium and narrow face, features more typical of people from Europe, the Near East, or India. Chatters had stumbled onto a mystery that until then had been known only to a few physical anthropologists. One of them was Douglas Owsley at the Smithsonian Institution.

DOUGLAS OWSLEY: Jim gave me a call and said that they were working on a skeleton and that it showed some features that were different from what he was expecting. Well, he explained the morphology. And that seemed like it could fit with the types of features, the types of characteristics that we had seen in some other skeletons from that time period.

NARRATOR: Over the past decade, anthropologists have detected a surprising pattern in the small handful of North American skeletons more than 8,000 years old.

DOUGLAS OWSLEY: Those are extremely rare. A well preserved skeleton that is that old, you could count the number of those on your fingers. As we began that systematic examination, we became totally dismayed at just how different the most ancient people are in terms of their physical features, their morphology.

NARRATOR: It seems that none of them looks like modern American Indians, who are presumably their descendants. Who they were and where they came from is a mystery - one that Kennewick Man might help to solve.

DOUGLAS OWSLEY: Because they are so few, that makes each one all the more important. And the fact that you might have one that is well preserved, with a nearly complete cranium, that could add just tremendous amounts of information to what we know about these people.

NARRATOR: Chatters was holding one of the most important anthropological finds of the century.

JAMES CHATTERS: I didn't expect that. I've never thought of myself as being that lucky. And as it turned out, I'm right. Four days after the date came in, I had a call from the coroner, saying, "Hey buddy, I've got bad news for you. I'm going to have to come get the bones."

NARRATOR: A coalition of five northwest Indian tribes, led by the Umatilla, had claimed the skeleton under NAGPRA - a federal law that provides for the return of Native American remains to their living descendants. The Umatilla believe they have lived in the Pacific Northwest since the beginning of time. If Kennewick Man was 9,000 years old, they said, he must be their ancestor, whatever he looked like. It's a feeling shared by many Native Americans.

BEA MEDICINE: Ancestors represent the tie to our world, to our earth. And we are very committed to respect and responsibility of how these human remains are treated and found.

NARRATOR: The Umatilla demanded a halt to all scientific study and the immediate return of the Kennewick Man for burial in a secret location. With the coroner on his way over to impound the bones, Chatters made a hasty record on videotape, thinking they might never be seen again.

JAMES CHATTERS: It was five o'clock in the evening - end of the work day, end of the week. I knew once the date came there would be very little time, but I thought, two weeks. But he came right over, within an hour, and that was the end of it.

NARRATOR: The Army Corps of Engineers was in charge. Scientists pleaded for a chance to study the bones first - but they were ignored.

DOUGLAS OWSLEY: We got no response from the Corps of Engineers and I got no response from the Umatilla. So it came down to the point that the skeleton was going to be turned over unless we took a more drastic measure.

NARRATOR: Owsley and seven other scientists filed suit in federal court to stop the return of the bones.

ROBSON BONNICHSEN: None of the scientists wanted to resort to a lawsuit. The government was moving forward with repatriation. We had no choice.

NARRATOR: If they did nothing, they risked losing all ancient skeletons, and the mystery of the first Americans might never be solved.

ROBSON BONNICHSEN: This is frustrating! We're in an enormously interesting time in our profession because we're starting to look at new ideas, and yet at the same time, we may not be able - or we may not be allowed to look at ancient human remains.

NARRATOR: The fate of the Kennewick Man is now in the hands of a federal judge.

DOUGLAS OWSLEY: The scientists have never said, "Kennewick Man is not Native American." He could be. Or he might not be. But what we have said is that he has to be studied. I feel that a clear and accurate understanding of the ancient past is something that the American public has a right to know about.

NARRATOR: For generations we've been taught that most Native Americans are descendants of a band of prehistoric hunters who walked to the New World from Asia about 12,000 years ago. The Asian connection was recognized from the beginning. American Indians seemed to resemble the people of Mongolia, China, and Siberia. In the 1930s, archaeologists near Clovis, New Mexico, found distinctive stone spear points among the bones of mammoths - a discovery that gave the first Americans an identity.

JOHN MONTGOMERY: This point would have been the ultimate in terms of a killing technology. And the fact that it was found embedded, in some cases, in mammoth remains, in the bones, it gave us this automatic picture of a very proficient hunter, and basically defined, based on this point type, that earliest culture called the Clovis culture.

NARRATOR: Clovis hunters left their stone points and butchered animal bones at kill sites all across North America. Radio carbon dating in the 1950s showed that the oldest site was 11,400 years old - and that date was the final piece of the puzzle. 11,400 years ago marked the end of the last Ice Age - a period when much of North America had been buried beneath massive glaciers up to two miles thick.

DAVID MELTZER: When you've got that much ice on land, what happens is is that it draws, essentially, water out of the oceans. So with that much ice on land, sea levels, worldwide, are lowered. By lowering sea levels, you expose the continental shelf between Siberia and Alaska. And so you create this entryway, this land bridge, and that made it possible for people to walk to the Americas.

NARRATOR: As the Ice Age came to an end, an ice-free corridor appeared between the receding glaciers, opening the door to the Americas for the first time, it seemed, in human history.

DAVID MELTZER: As that corridor opens up, maybe about 11,500, 12,000 years ago, that's just about the time when Clovis appears in the lower 48. So it all seemed to work out very, very beautifully in terms of the timing of getting these New World peoples from Asia into the Americas.

NARRATOR: It was a simple, persuasive story - a small band of nomadic hunters from Asia, colonizing a virgin landscape. Over thousands of years, they spread to every corner of the New World, and gave rise to most of the native people in the Americas today. This was the gospel of American archaeology.

DOUGLAS OWSLEY: But now there's been some real changes in the thinking of this. And this model is - too simple.

NARRATOR: The biggest challenge to the Clovis story comes from the southern hemisphere. In 1996, a group of prominent archaeologists met in southern Chile at a place called Monte Verde. They'd come to look at evidence of a human habitation site - reputedly, 1,000 years older than Clovis. They saw weapons, tools and other artifacts dated to 12,500 years old. Everyone was convinced. Clovis was not first after all. More evidence comes from southern Brazil. In prehistoric rock shelters, archaeologists have found some of the oldest human remains in the New World. As in North America, these early skulls don't look anything like present day Indians. One skeleton, called Luzia, is more than 11,000 years old.

JOSEPH POWELL: The date of 11,000 makes her potentially the oldest skeleton in the New World, and the fact that Luzia looks so very different may imply that she was part of a different population. The question of how she got there is another one altogether because her early age, combined with data from Monte Verde which is at least 12-13,000 years old, certainly means that people must have been migrating into South America much earlier than we previously thought.

DAVID MELTZER: That's a complicated issue because what it means is that they must have come in long before this ice-free corridor opened. And that raises lots of questions about the route that they took, how early they got here, what population or populations we're talking about here, whether there were single or multiple migrations.

JAMES CHATTERS: We don't really know who these early people were. We don't know how many people came and we don't know when they came in. So the whole idea about one migration across the Bering Land Bridge 12,000 years ago and moving into America, accounting for all peoples, all languages, all cultures is now thrown out. It's gone.

NARRATOR: But one fact from the old Clovis story remains unchanged - the Ice Age glaciers that once blocked the way from Asia to North America began to recede only about 12,000 years ago. If people were coming into the New World before that, how did they get past the ice? Archaeologists are now searching for answers along the Alaskan coast. What was it like during the Ice Age?

JAMES DIXON: Well, when I was a student we learned that the entire northwest coast of North America was covered by glacial ice all the way out to the continental shelf. So really, there was no opportunity for plants or animals, much less humans, to exist along that coastline during the last Ice Age.

NARRATOR: Jim Dixon and Tim Heaton have been taking a closer look at the environment of Alaska's coastline during the last Ice Age. Their work is changing our view of how and when the first Americans could have moved into the New World.

TIM HEATON: We just cleaned up this caribou antler I want you to take a look at.

JAMES DIXON: Oh, very nice!

NARRATOR: They've found evidence of abundant plants and animals at a time when the coast was thought to be a lifeless, frozen wasteland.

JAMES DIXON: No doubt it's a caribou. It's a magnificent specimen.

NARRATOR: Archaeology in this terrain is difficult. Most of the Ice Age coastline is underwater now, submerged by the rising sea level as the glaciers melted. The forest is a tangle of roots and vegetation that makes excavation nearly impossible. But scattered along this coast there are places where evidence of ancient life has accumulated undisturbed for tens of thousands of years. This is where Heaton and Dixon do their work - in ancient bear caves, deep underground. The cave floor is excavated inch by inch from dated layers of soil.

ARCHAEOLOGIST: Here, let me take one of those bags. Thanks.

NARRATOR: Then, everything is hauled out to the surface for closer inspection. Above ground, they strain the sediment through filter bags.

JAMES DIXON: Eventually, when I get down to the bottom there'll just be a small amount of small stones, and there might be a flake or a piece of bone or something in there.

TIM HEATON: I think it's a bone fragment.

NARRATOR: Every tiny piece of stone and bone is bagged and labeled for later analysis.

ARCHAEOLOGIST: Looks like wood.

NARRATOR: Yarrow Vaara is one of several Native Americans on the project.

YARROW VAARA: It's really exciting, every time when you so much as clink a rock, it could be an artifact, you never know what it could be, it could a 10,000-year-old tool, it could be a bone, it could be - it could be anything. You just don't know, and so whenever you hear anything, you have to go around it really carefully and find out what it is.

NARRATOR: This excavation has uncovered a continuous record of caribou, fox, and bear bones dating back 50,000 years.

TIM HEATON: Also in this cave we've found seal bones that appeared to be scavenged by bears. What this suggests is that bears survived the entire last period of glaciation, and if bears could have survived here, it's certainly clear that humans could have also.

NARRATOR: They weren't expecting to find human remains, but one day Heaton made a surprising discovery.

TIM HEATON: I was actually filling the very last bag of sediment on the last day of the excavation when, as I reached under this shelf, I flipped up a bone about this long, which turned out to be a tool, a bone tool. And because of that, I started feeling down in the very soupy sediments below, and I started pulling up pieces of jaw. There were so many I couldn't identify them immediately. But I found four different elements here that turned out to be parts of a human mandible and a human pelvis as well as a tool.

NARRATOR: The jawbone turned out to be more than 9,000 years old.

JAMES DIXON: This is a cast of the mandible that provides a lot of evidence about the individual and the individual's diet. As you can tell from looking at the teeth, they're rather heavily worn for an individual of this age. It's a young man about 23 years of age. And the reason we can tell that is the wisdom teeth, or these last molars to erupt, one has erupted and it's actually made contact with the upper teeth and is worn. The other has erupted but not made contact with the upper teeth. So this suggests he's in his early 20s. There are some slight indentations or nicks or notches in his front teeth here, the teeth that are still preserved, and this suggests he did some kind of repetitive task with a line or sinew in his teeth, either holding line or tying line. We've also done isotope analysis on the bone. And this suggests that the individual's diet was largely marine foods. In fact, his isotopic signature is so strong that it's equal to marine mammals such as ring seal and oceangoing fish. So this is incredible. This clearly shows that this young man was raised on a diet of marine foods.

NARRATOR: For Yarrow Vaara, this is like getting to know a long lost member of the family.

YARROW VAARA: I can trace my lineage back at least 19 generations to the origin of Kuwok. So to me that's really fascinating to think that the man who was found in this cave could be my great-great-great-grandfather at some point 10,000 years ago.

NARRATOR: In this case, at least, scientists and Native Americans have found a way to co-exist.

MILLIE STEVENS: We don't have to stop and wonder, well, how long have we been here? Where did we come from? We know. It isn't a guessing game. We know. But it carbon dates almost 10,000 years old, you know, so this, our legends - so the legends that we've been told, all along, you know, that's evidence that we've been here before the Ice Age.

NARRATOR: It appears that the Ice Age glaciers were not a barrier to the New World after all.

JAMES DIXON: We now realize that those early portrayals of this massive continental glacier all the way out to the ocean really is, is not accurate. And that by, oh, 14 to 16,000 years ago, this ice had retreated sufficiently to create habitat for plants and animals and ice-free areas that could have been used by humans.

NARRATOR: If the first Americans migrated along the coast from Asia, they could have reached the New World long before the ice melted away. The problem now is to discover the identity of those early people. The only direct evidence comes from human skeletons in collections like this one at the Nevada State Museum - and those may soon be gone. NAGPRA requires all museums to inventory their collections, determine which remains can be connected with present day Indian tribes, and make them available for reburial. None of the remains shown here is Native American, because state law prohibits their display in public.

AMY DANSIE: We never used to expect to have a time limit on when we could do the burials. And there was always an assumption that we'd have generations of scientific efforts to study these. That's why they're so carefully stored in a museum. Now all of a sudden, we have to come to grips with the law that demands repatriation if they are affiliated with living people.

NARRATOR: Doug Owsley and a team from the Smithsonian are helping with the inventory.

DOUGLAS OWSLEY: All right, we'll just go - sex and race, and we'll deal with age at the end of it.

____: Gotcha.

DOUGLAS OWSLEY: We are faced with the loss of human skeletal collections, irreplaceable collections. So what we decided to do was to carefully collect certain kinds of information that we knew how to analyze to try and minimize that loss. And with the kinds of information that we collect and the databases that we have, we can often assist in the process of determining tribal affiliation.

NARRATOR: Analyzing the shape or morphology of the skulls is part of the process. The business of measuring skulls has a dark past. A century ago, physical anthropologists used distorted data to argue that Africans, Asians and Indians were separate human species, inferior to white Europeans. To some degree, the field has carried the stigma of racism ever since. But the modern science is not about racial type casting. It's about understanding human diversity.

DOUGLAS OWSLEY: The human skull shows a lot of variability among different world populations. And those features are determined, in part, by ancestry. In collecting cranial measurements, we take over 60 measurements of different dimensions on the human skull. And so some measurements deal with breadth, some of them deal with height of the cranium. Some of them deal with facial forwardness, the projection in this dimension.

NARRATOR: Researchers have compiled measurement data on dozens of populations from around the world. With a large enough sample size, a statistical analysis can show the range of variability in a given population, and whether an individual falls inside the range - or outside. This technique has helped the museum identify and repatriate more than 100 ancestors of western Nevada Paiute Indians. But it's also turned up yet another mystery skeleton, like Kennewick Man, that cannot be connected with any modern tribe. It was discovered in the western Nevada desert 60 years ago, and has been in the museum collection ever since. The Spirit Cave Man was so well preserved, it was not thought to be very old. But recently, the museum decided to have it radio carbon dated. In the past, extracting enough carbon from bone to obtain a date would destroy a large piece of the skeleton, so it was rarely done. But today it takes less than half a gram of bone, and the dates are accurate to within 60 or 70 years. The Spirit Cave Man turned out to be 9,400 years old. At which point, the Fallon Paiute-Shoshone tribe claimed him under NAGPRA.

AMY DANSIE: Now we are under a legal challenge as to whether or not we have the right to proceed with our study. I don't know how far that will go, but it may go to court.

DOUGLAS OWSLEY: When you're talking about recent human skeletal remains, certainly that is within the rights of the tribes, to claim those skeletons. But when you start getting 1,000 years old, or 5,000 years old, or 9,000 years old, it becomes arguably much more difficult to demonstrate a clear cultural affiliation. And certainly to demonstrate that affiliation requires scientific study.

NARRATOR: The Spirit Cave Man's skeleton is off limits to NOVA's camera. But it's still possible to get a sense of what he looked like. A reconstruction of his living face begins with a 3-D CAT scan of the skull. At a medical imaging laboratory, the data is projected by laser into a tank of liquid resin, which hardens at the focal point of the beam. The result is an accurate replica of the Spirit Cave Man's skull. In the hands of forensic sculptor Sharon Long, it's the basis for a reconstruction of his face. She starts with depth markers that will determine the thickness of the facial tissue. Then she builds the face, using techniques developed and tested in criminal forensic cases. The contours of the skull and specific muscle attachment points determine things like the shape of the mouth, the length and width of the nose, and the opening for the eye.

DOUGLAS OWSLEY: Where you tend to miss is in those features that are really individualizing - how many wrinkles the individual has, for instance. How much weight the person is carrying. Those kinds of features that are really specific. But the underlying contour and the underlying profile is defined by the shape of the skull.

NARRATOR: Gradually, the face of the 9,400-year-old Spirit Cave Man is revealed. But is it the face of an American Indian - or someone else? Native Americans have always been considered close relatives of the so-called Mongoloid people of northeast Asia. But the Spirit Cave Man seems more Caucasoid, like the people of Europe, the Near East, or India, especially when compared with two other faces from the Nevada State collection - Wizard's Beach Man and an 850-year-old Native American from Nevada.

AMY DANSIE: We've noticed that in the overall profiles of the three faces the degree of facial forwardness, or prognathism, varies quite a bit. Spirit Cave Man has virtually none, and that's one of the traits that has been referred to as Caucasoid. Wizard's Beach Man is kind of in between the two of them in that respect, and you can see the difference when you look at the later Native American, where his face sticks out from an up and down plane. Another characteristic that is surprising about the Spirit Cave Man is his small bilobed or bifurcate chin. It's really quite pointed, and this is usually considered a Caucasoid trait. This is one of the traits that forensic anthropologists look for. It's also fairly small, the jaw is fairly small compared to the Native American, where it comes way down, very strong and square. This square jaw is one of the traits that is used to identify Native Americans.

NARRATOR: If Spirit Cave Man was the only early American with these features, he might be explained as simply an odd looking Indian. But he's not the only one. A year and a half after Kennewick Man was taken away, Jim Chatters was still one of the few people who had ever seen the skeleton. He had constant calls from the media asking for a description, so he decided to try a facial reconstruction of his own. He started with a cast he'd made from the original skull.

JAMES CHATTERS: That came out pretty good.

TOM McCLELLAND: Yeah. Well, we'll bring this jowl down a little bit -

NARRATOR: He and sculptor Tom McClelland tried a different technique, first building the underlying facial muscles, and then applying the skin.

JAMES CHATTERS: How do you like what I did with that cheekbone?

TOM McCLELLAND: I see what you did. That's good.

JAMES CHATTERS: Yeah, he's looking pretty good now. We can probably let him go at this point.

TOM McCLELLAND: Very believable.

NARRATOR: The result bore a striking resemblance to British actor Patrick Stewart, and caused a great deal of confusion. Were the first Americans really Europeans? Chatters described the face of Kennewick Man as having "Caucasoid" traits - but the headline said "white." Some people blamed Chatters for stirring up racial conflict.

JAMES CHATTERS: I was taken completely by surprise by the accusation of racializing an ancient skeleton, for saying it was Caucasoid-like in characteristics. To me, that was a descriptive concept. It told people what it looked like.

NARRATOR: The concept of race, itself, is controversial. Since there are no clearly defined boundaries between races, some think that race has no biological meaning at all, and to say that it does promotes racism.

JAMES CHATTERS: It's become a political quest, and I think that's what's driving this, to a great extent, is more modern day political correctness than actual good science and good biology. There are differences between people. There are good historical reasons for those differences to exist. They tell a story about the history of those populations.

NARRATOR: Doug Owsley and colleague Richard Jantz are trying to sort out that history. They've done a statistical analysis of the half dozen American skulls more than 8,000 years old to see where they fall in relation to modern people.

DOUGLAS OWSLEY: We can compare each one, as a group or individually, to one of these modern populations that are in our reference samples from North America, from Asia, from Europe, from other parts of the world. Well, when you do that what you find is that they're not modern, they're distinctively different. And the one grouping that they're very far from in terms of their morphology is Native Americans.

NARRATOR: But they don't fall in the range of Europeans or any other modern people, either.

DOUGLAS OWSLEY: But if you were to force the question and say, who are they most like, you could do that. And if you did that in the case of Spirit Cave, for instance, what you'd find is that statistically, the population that he's most like is the Ainu of Japan.

NARRATOR: The Ainu are the indigenous people of Japan. Their ancestry reaches back deep into prehistory, long before the ethnic Japanese arrived some 2000 years ago. Today there are fewer than 100 full-blooded Ainu left. But in the 19th century, there were many more. Anthropologists called them Asiatic Caucasoids, because they had facial features and body hair that seemed more European than Asian. In fact, the Ainu are thought to be a remnant of a very ancient population that was once widespread in the Old World. The first anatomically modern humans are thought to have come out of Africa about 100,000 years ago, and spread throughout Europe and Asia.

DOUGLAS OWSLEY: The first people in Asia, morphologically, are very similar to the people that are going into Europe. They don't show the really distinctive, unique features that we see in northern Asian populations of today, like the Chinese or the Koreans, Siberian groups. And they are the very first people in Asia.

RICHARD JANTZ: This is 28,000 years, from China -

NARRATOR: What we know of these early Asians is based on just a few skulls.

RICHARD JANTZ: - it's one of the earliest anatomically modern homo sapiens in Asia.

NARRATOR: One of them is a 28,000-year-old specimen from China, which looks very much like the 9,000-year-old Spirit Cave Man.

RICHARD JANTZ: And there are some marked similarities in the facial architecture.

DOUGLAS OWSLEY: Tremendous similarity in the shapes of the eye orbits in the sense that they're both somewhat rectangular, similar interorbital distance, overall appearance of the orbits, shape of the nose. And it's a little bit smaller skull, it's a little bit more lightly built, but many of the features, including the very heavy mandible and the prominent symphysis here, those features are very much the same.

RICHARD JANTZ: And let's look at it from the side.

DOUGLAS OWSLEY: How's the overall shape of the vault?

RICHARD JANTZ: Not bad, is it? Not bad.

NARRATOR: So the key to understanding the first Americans is not that they looked like Europeans, but that they looked like Asians - at least, the way some Asians looked 20,000 years ago, when people were on their way to the New World. Further complicating the picture, the oldest skeletons found in South America appear to be related to a different group of early Asians.

JOSEPH POWELL: Spirit Cave Man, for example, doesn't look a whole lot like these 9,000-year-old skeletons from Brazil. And in many ways, the South American samples look much more like Australian aborigines or people from Melanesia.

NARRATOR: The 11,400-year-old skeleton called Luzia is one of those early South Americans who resembles Australian aborigines. But that doesn't mean that she came from Australia.

JOSEPH POWELL: What may be going on is that Luzia represents a group of people who started from a central place in Asia, some of whom migrated south into Australia, others who came into the New World. We're not saying that Australians came across in boats, but simply that those two populations, at some point, could have had common ancestry.

NARRATOR: The evidence points to a major change from the earliest people of the New World to modern Native Americans. The question now is, how did that change happen? One possibility is that the early ones, like Spirit Cave Man, evolved into modern people by a process called genetic drift.

JOSEPH POWELL: Imagine this is a group of Paleo-Indians with a certain amount of diversity within them, as there is within any group of humans. As they enter into the New World they spread out, not just geographically but biologically, through the random process of genetic drift. For example, one group may be caught in an avalanche and everyone dies. They're extinct. Another group is severely affected by epidemic disease. Maybe this is the group that Spirit Cave Man belonged to. So very few people in that group survive. In fact, Spirit Cave Man dies and is buried in the cave. Other groups begin to grow in size, they become larger through time, and they begin to act like biological magnets, pulling the smaller groups closer and closer towards them. As that happens, they become more and more similar genetically and morphologically, so they share a common appearance. Eventually, we have much less diversity than we originally started out with. 9,000 years later, when Spirit Cave Man's skeleton is found, he doesn't look like any of the people today. But that doesn't mean he wasn't part of the original founding group.

NARRATOR: Another possibility is that the first Americans were replaced by later people who brought in a different look. It's believed that people with the so-called Mongoloid features of modern Asians first appeared toward the end of the Ice Age, and eventually replaced most of their earlier cousins in eastern Asia. But what happened in the New World? Owsley and Jantz believe that early Americans, like Kennewick Man on the right, were also replaced by these Mongoloid Asians - people who appear abruptly in the fossil record, and look more like modern Native Americans.

DOUGLAS OWSLEY: By at least 7,000 years ago, we see the northern Asiatic face beginning to appear - a very broad face, a tendency towards a round head. And we see those individuals coming into the New World. And they're distinctively different. You can recognize, you can see metrically but also visually these northern Asiatic features that represent later migrants into the New World.

NARRATOR: The old Clovis story said that a single founding population from Asia gave rise to most of the native people in the Americas - and that their doorway to the New World did not open until the end of the Ice Age. But the human fossil record, and the archaeology from Alaska, tell a different story. Parts of the coast were ice-free, even when glaciers covered half of North America. So a coastal migration route would have been open to the early people of Asia - like the ancestors of the Ainu and the Australians - people who resemble the first inhabitants of the New World. Then, as the glaciers began to recede between 11 and 12,000 years ago, the interior route opened up - a natural pathway, perhaps, for nomadic hunters from northeast Asia.

DAVID MELTZER: So these could be very, very different populations, coming into the New World literally thousands of years apart from one another, possibly from different sources in northeastern Asia, we don't really know that. But certainly we are looking at the possibility of multiple migrations into the New World, possibly going on different routes.

NARRATOR: It also appears that the human tendency toward conflict with strangers was part of the picture.

JAMES CHATTERS: One of the most surprising things that I've seen in looking at these early skeletons is the level of violence, the level of conflict between people. Kennewick Man has a spear point embedded in his pelvis, and he's got a head wound that could easily be from an assailant. Spirit Cave has a fractured skull. It's becoming commonplace to see these individuals with serious injuries inflicted by other people. It's not what we would expect to see. Our idea about low population density hunter-gatherers is that they were generally, you know, lived peaceful lives in egalitarian societies and so on. That may not be true at all.

NARRATOR: Was the New World a battlefield, or a melting pot of Old World clans? Most likely, it was both.

JOSEPH POWELL: We may not be able to pick out one process alone. This is a very complex issue. You may have people moving in, you may have gene flow, you may have genetic drift, all of those things working together are creating the picture that we see today.

NARRATOR: Genetic studies may someday tell us more about the complex origins of the earliest Americans and how they relate to modern people. But it may never be possible to connect a 9,000-year-old skeleton with any particular living group.

JOSEPH POWELL: As we move farther and farther back in time, it becomes more and more difficult to find a direct lineal connection, and that's the problem we run into with these early skeletons is that, are they so far back in time that they are the ancestor of all groups or, perhaps, none? It requires that at least some of those early people left behind descendants. If they had no kids, we're not going to be able to trace that connection, and at any point over those 400 generations between the end of the Pleistocene and today, it's possible to break the chain.

NARRATOR: As the court case drags on, the fate of Kennewick Man is still unresolved. A team of government appointed scientists found that he was not closely related to any American Indians, and that he was, instead, closer to the Ainu. But the case is not over. Because he predates Christopher Columbus, Kennewick Man is, by legal definition, Native American. The Umatilla claim to his bones is still pending. Joe Powell was a member of the government team.

JOSEPH POWELL: The political situation puts a lot of pressure on scientists. To say that these early skeletons are not related to modern American Indians has political ramifications for modern groups of people, indigenous people in the Americas. To say that - to deny that they are different also has potential ramifications, both from a scientific and political standpoint. So, this whole issue is tied up in politics to some degree. Scientists have worked very hard to try to extract themselves from that, but it can't be avoided.

NARRATOR: All stories of early human history are incomplete. Advances in human genetics, archaeology and anthropology will add new chapters - or perhaps rewrite it altogether.

DOUGLAS OWSLEY: I think one of the things that we have to realize is that the story is very complicated. We haven't begun to figure it out.

NARRATOR: The search for scientific truth requires evidence. Without it, mysteries will remain mysteries forever. The future of this science will depend on finding common ground with the Native people who view all the ancient ones as their ancestors.

BEA MEDICINE: Among the Lakota, we have a term that says [speaks in Lakota], which means "all my relatives." And that means, you know, the deceased, it means the living, it means the future people. So the notion of ancestry and kinship is exceedingly important to all Native peoples.

AMY DANSIE: There are many other issues besides physical reality and facts involved in something like this. Human feelings, humans' perception of sacredness and spirituality, and whether the human spirit is still sensitively involved with its mortal remains. I mean, these are questions no human has ever been able to answer to the satisfaction of any other human. These are all unknowns that science can't even touch.

NARRATOR: If we look back far enough in time, all people are members of a single family. How we came to exist everywhere on earth and in such variety is our collective story, and one we're just beginning to understand.

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____: Those are our blood relatives.

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