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Dennis Stanford and Bruce Bradley with a Clovis spear point
BBC Two, Thursday 21 November, 9pm
Stone Age Columbus
Next on Horizon
Homeopathic medicine defies scientific logic. How can diluting a drug make it more potent? In Homeopathy: The Test, Horizon pits sceptics against believers.

Stone Age Columbus - transcript

NARRATOR (JACK FORTUNE): This is the story of one of the greatest voyages in human history. It was a journey which took people across thousands of miles of snow and ice through some of the most extreme weather ever seen on Earth, but these were not famous polar explorers like Scott or Shackleton and they weren't adventurers in search of conquest. These were men, women and children travelling across oceans and ice floes in search of a better life and this is more than just an epic journey. It is threatening to rewrite one of the greatest stories of them all. For these people were travelling across the Atlantic from Europe to America and they would get there 17,000 years before Columbus, in the Stone Age. Last year archaeologist Bruce Bradley went on a mission to France to challenge one of the most widely accepted theories of early human history and here, in the back room of this small museum, he found exactly the evidence he was looking for because amid the arrowheads and needles he found something which by rights should not have been here at all, some distinctive two-sided spearheads that are at least 17,000 years old.

DR BRUCE BRADLEY (Smithsonian Institution): When I first saw this material when it was first brought out I was astounded, I was shocked, I was absolutely flabbergasted. Here is what we needed.

NARRATOR: Because of what he saw a mystery that everyone thought was solved will have to be reopened, for these spearheads say that one of the great sagas of pre-history, the tale of who were the first people to populate America, will have to be rewritten. Once upon a time we thought we knew it all. The story of who had been the first settlers in America was one of the most studied in archaeology.

DR PAUL MARTIN (University of Arizona): I think to know when people first came into the New World is important. Archaeologists have been looking for the earliest for a long time. It's been a Holy Grail for them - who was first.

NARRATOR: The answer it seemed lay with one remarkable find. In 1933 in a dried-up lake in Clovis, New Mexico archaeologists uncovered an ancient spearhead. It became known as the Clovis Point.

DR DENNIS STANFORD (Smithsonian Institution): It's a very distinctive type of artefact. As you can see here it has a flake that's been taken out of the base and there's also a, a flake on the other side removed from the base and these are called flutes and beyond that the projectile point is flaked on both sides. You see it's worked here and it's worked on this side which is what we call bifacial.

NARRATOR: And alongside the Clovis Point was one huge clue to its age. The skeleton of a mammoth which it had clearly been used to kill. When they dated the bones they found they were 11,500 years old. It made the Clovis Point the oldest human artefact ever found in America. That was just the beginning. Soon all over the country archaeologists were finding thousands of similar, beautifully crafted flints, from tiny arrowheads to much larger possible ceremonial pieces, all made in the same distinctive way. The Clovis Point soon became the icon of the first Americans.

DR MICHAEL COLLINS (University of Texas): There's Clovis in every one of the 48 states in the United States, Mexico, Belize, Costa Rica, in all kinds of environments. The Clovis Point itself, it may be the first really great American technological invention.

NARRATOR: And all these Clovis Points didn't just look the same. They all seemed to date from the same time, 11,500 years ago and then the archaeologists noticed something that transformed the Clovis story into one of the great sagas of human history. 11,500 years ago it was not just one mammoth that met a bloody end - they all did and a host of other great Stone Age beasts in America - the giant armadillo, the giant sloth, the great black bear - all were wiped out in just a few brutal years.

PAUL MARTIN: It was large animals for the most part that disappeared. It looks as though it didn't take long at all. It looks as thought it was over almost as soon as it began.

NARRATOR: And so an epic story was born. Somehow from somewhere 11,500 years ago people arrived in America for the first time. Whoever they were they were warriors and they brought with them a fearsome weapon, the Clovis Point. In just a few years they charged down the length of the continent killing all the great beasts as they went. It was a fantastic story. There was only one outstanding question: where did this intrepid band of hunters come from, who were they? When the archaeologists looked for an answer they found it in the weather of the Ancient World. 11,500 years ago was the end of the last great Ice Age. Huge swathes of the northern hemisphere still lay frozen under ice. These giant ice-sheets locked up vast quantities of water. It meant that sea-levels were far lower than they are now. Huge tracks of land were exposed meaning the continents of Asia and America were joined with a bridge of land linking Siberia and Alaska across what is now the Baring Strait. It seemed clear that this was the route the Clovis people must have taken as they undertook an intrepid journey across into a new continent 11,500 years ago, so their story entered the history books. The first Americans were the Clovis, a people from Asia, and they had stayed isolated ruling America for 11,000 years until their first fatal contact with Columbus and the people of Europe in 1492. It became an accepted fact. It was such a powerful story that for years no archaeologist bothered to look back beyond 11,500 years ago. Everyone knew there could be nothing there, so no-one dug any deeper, but one day somebody did. Jim Adovasio has spent the past 30 years excavating an ancient settlement near Pittsburgh. Layer upon layer telling the story of who lived here and when going back at least 11,000 years.

DR JIM ADOVASIO (Mercyhurst Archaeological Institute): On these surfaces that you see before us we have signs of repeated visits by Native Americans to this site. These discolorations literally represent a moment frozen in time. Just below the surface I'm standing on roughly 11,000-11,200 years ago is where the conventional Clovis first model says that the earliest material should stop basically, that there ought not to be anything beneath it, no matter how much deeper we dug.

NARRATOR: But then Adovasio did the unthinkable - he dug below the Clovis layer - and that's when the trouble started.

JIM ADOVASIO: The artefacts simply continued and we recovered blades and blade cores like this all the way down to 16,000BC.

NARRATOR: If Adovasio was right then someone had been in America thousands of years before Clovis. It was an astonishing revelation. In fact it was too astonishing. When Adovasio published his findings he was simply dismissed out of hand.

JIM ADOVASIO: The majority of the archaeological community was acutely sceptical and they invented all kinds of reasons why these dates couldn't possibly be right. People have invested in the Clovis first position for more than 70 years. For a lot of people they think that this is not only a repudiation of a well accepted dogma, it's a repudiation of themselves.

NARRATOR: And so it was for other scientists. Anyone who dug back beyond 11,500 years ago had to be either mad or worse.

MICHAEL COLLINS: The best way in the world to get beaten up professionally is to claim you have a pre-Clovis site.

DENNIS STANFORD: When you dig deeper than Clovis a lot of people do not report it because they're worried about the reaction of their colleagues.

MICHAEL COLLINS: And then accused of planting artefacts. People will reject radiocarbon dates if they're older than 11,500 years ago just simply because there's not supposed to be any people here at those times and it just goes on and on and on.

NARRATOR: And so it could have stayed. The Clovis theory remained dominant with just a few awkward dissenters, but then something happened which opened up the whole mystery once more. Douglas Wallace is not an archaeologist, but nonetheless he is trying to write a complete history of the world. It's just that his history is based on the science of genetics. Stored at temperatures below minus 250°C he has samples of DNA from every part of the world, a complete record of who we all are and where we came from.

DR DOUGLAS WALLACE (Emory University): We can get insight into our history by looking at modern DNA samples. If and when we need a sample from a population in Africa or a population in Asia we can then go to that tube, pull that tube out, resurrect those cells, amplify them, isolate their DNA and ask yet a new question.

NARRATOR: Wallace was particularly interested in a type of DNA called mitochondrial DNA. As humans reproduce mitochondrial DNA is passed along the female line from mother to daughter. The only change that takes place is when there are mistakes in copying as the cells reproduce. The mistakes are called mutations and they take place with a clock-like regularity. By comparing the number of mutations in his samples from around the globe Wallace could trace not only the route our ancestors followed as they migrated across the planet, but also when they did it.

DOUGLAS WALLACE: So what we've been able to do using genetic variation and comparing the genetic variation of aboriginal populations from all the major continents of the world we've literally been able to reconstruct the history of migration.

NARRATOR: Sp the DNA should tell Wallace not just where the first American came from, but even when they made the journey. When he looked at his samples he found that genetically speaking every Native American's DNA was made up of a combination of four groups which he called A, B, C and D. They all came from Siberia and north-eastern Asia. So far this discovery was consistent with the Clovis theory, but then came the revelation. When he worked out the dates he realised there were several waves of migration and the earliest group had come over nearly 10,000 years before the Clovis, some 20,000 years ago. Immediately Wallace thought he had to be wrong. He repeated his work. So did other labs. The results were absolutely clear.

DOUGLAS WALLACE: All of the papers that had been published have come to a very similar conclusion: that the first migration was in the order of 20,000-30,000 years ago.

NARRATOR: There was now no doubt. The epic Clovis theory had to be wrong. The great quest to uncover the story of the early settlement of America had to start all over again. Archaeologists decided to go back to basics and none more so than Dennis Stanford from the Smithsonian Institute. He started with what was still the only real clue: the Clovis Point itself. He decided to look for spear points along the route from Asia to America trying to see if he could trace the people who had brought the Clovis Point to the Americas, but as he worked back through Alaska and then Siberia the trail went dead. The only tools he found were quite different.

DENNIS STANFORD: After looking at the collections we were disappointed that we didn't find what we thought we would find and I was surprised to find that the technologies were so much different.

NARRATOR: In Siberia he found Asian tools that bore no relation to Clovis Points at all. Most were made from lots of small flints called micro- blades embedded in a bone handle.

DENNIS STANFORD: Microblade technology is striking a long thin flake from the core and then making a projectile point or a knife blade out of bone and then cutting a slot in it and then putting the microblade in the slot and that's a totally different philosophy entirely than using the bifacial projectile point, as you can see here, it's just a total different mindset.

NARRATOR: There was now a real puzzle. The DNA said the earliest Americans could only have come from Asia, yet the Clovis Points seemed to have come from somewhere else. The man who set out to solve this paradox was archaeologist Bruce Bradley. Bradley has a skill that allows him to see things in stone tools that others cannot. He's a flint knapper, an expert at crafting flint objects.

BRUCE BRADLEY: So what I'm doing here is I'm choosing to be Clovis, in other words I'm choosing a Clovis approach to this piece of stone now. I'm going to grind it a little bit, strengthen it.

NARRATOR: If he could work out how the Points had been made it might be a clue to who the people were who had brought them to America.

BRUCE BRADLEY: Every piece that we find, if you know how to read it, can tell you the story of the technology from which it comes.

NARRATOR: What Bradley found was that the Clovis Points didn't just look distinctive, they had also been made in a very distinctive way.

BRUCE BRADLEY: You can see how this, starting from this side went and took off this whole other side. This is what we call an overshot outré passé flake, a very intentional process. Now I've set up to do, go this way.

NARRATOR: The result of this process is that the flint flakes off in large, useable chunks. Such flakes have been found wherever you find Clovis Points.

BRUCE BRADLEY: Not only do I have a spear point, but with this technology I have a large number of big, useable flakes that are going to be very good for making other kinds of tools and so every single flake has that little story to tell.

NARRATOR: Bradley was certain that the big flakes had to be a clue. Whoever had made the Clovis Point had used a technique quite different to that used in Asia, so where had they come from and then he remembered a textbook he had seen when he was a student. It showed pictures of ancient spearheads made 20,000 years ago, long before Clovis, by a people called the Solutreans, but their points looked very like Clovis Points. The trouble was that the Solutreans came from France.

BRUCE BRADLEY: Even then I was thinking this can't be right, something's going on.

NARRATOR: Nevertheless, the idea began to form in his mind. No matter what the textbooks of the DNA might say, perhaps some of the earliest Americans were not Asian, but European.

BRUCE BRADLEY: It was sacrilege to even mention the possibility, you know, it, it certainly wasn't part of the scientific process at that point in time. There was no possibility, forget it, don't even think about it.

NARRATOR: The heresy was that it was a challenge to the identity of Native Americans. They believed they were an Asian people with no European blood at all. It had long been a crucial part of their culture.

DR LAWRENCE GUY STRAUS (University of New Mexico): Before we run around suggesting that the Native Americans of Asian origin are not the original peoplers of the Americas, we should think long and hard about what the consequences of saying those things might be. There are historical reasons for that.

DR JOALLYN ARCHAMBAULT (American Indian Programme, Smithsonian Institution): Some Indian people will undoubtedly find it upsetting. The thought that some of our ancestors might come from Europe, the very peoples who conquered us and took away our land and colonised us, will not be a comfortable thought with many Indian people and I really can't blame them.

NARRATOR: Despite the controversy Bradley was stirring up, he decided to pursue his idea. He went to south-western France where the Solutreans had lived 17,000 years earlier. In his mind was one simple question: could they possibly have been amongst the first Americans? In France one thing became abundantly clear. The Solutreans were a remarkable people.

BRUCE BRADLEY: Of all the Stone Age cultures that we've studied, the Solutrean people continually come out as being the most innovative, the most adaptive and probably the most inventive. We have evidence that they invented the heat treatment of flint to make it better to flake. I mean they invented all kinds of things like the eyed needle and the, the list goes on and on and on.

NARRATOR: Bradley's research took him to the local museum in the town of Les Eyzies. What he saw were displays of hundreds of what looked very like Clovis Points.

BRUCE BRADLEY: I see this stuff and I just, it's, I don't know, it's so exciting. The similarity is just, it's mind-boggling.

NARRATOR: But the close similarity of the spearheads was not enough.

BRUCE BRADLEY: What we're seeing here is only the finished objects, only the things that museum people thought were really good for display. It doesn't always show you how things were made.

NARRATOR: To establish a link between the Solutreans and the earliest Americans he needed to find out if they shared the same technology. Had the Solutreans used the same big flake method to make those spearheads?

BRUCE BRADLEY: So what we do is we go back to the collections of the broken materials which is probably 99% of what there is here and in that we're seeing the various ways that the Solutrean were making the things, not just the finished objects and so it's the pieces that are hidden away that are going to tell us the most.

NARRATOR: And there in the drawers he found what he needed, clear signs that the Solutreans really had made their spearheads just like the early Americans.

BRUCE BRADLEY: The thing that I first noticed when I looked in this drawer specifically was a few pieces right on the very top - this is a good example here - that shows a kind of flaking that, where the flake is struck from one side and went across the surface removed some of the other side and these pieces show it over and over and over again. I mean just about any piece you pick up shows this very special technique. This is the technique we see uniquely in Clovis and when I saw so much of it just sitting there I just knew there had to be some kind of a connection. There's nothing in here specifically that makes them Solutrean except that we're in France and they came from here.

NARRATOR: To Bradley it was the first proof of a direct link between the people of America and Europe, but critics pointed to one problem in particular. The Solutreans had lived 17,000 years ago and the Clovis Point had apparently not arrived in America until 11,500 years ago. Where had the Solutreans been in the intervening five thousand years? It was a question that even troubled Bradley's colleagues.

DENNIS STANFORD: I was going through the old arguments, yeah, well Solutreans, five thousand years older than Clovis and you've got the Atlantic Ocean out there, so I wasn't convinced that we really ought to push forward on it.

BRUCE BRADLEY: I remember it a little bit differently. You said are you out of your mind?

NARRATOR: Bradley needed to find something to bridge the 5,000 year gap between the Solutreans and the Clovis and then from a site called Cactus Hill in Virginia a wonder: a Solutrean-style point and it dated from far earlier than the Clovis.

DENNIS STANFORD: And here we have a projectile point from a feature that dates right at 15,900 years or 16,000 years ago which is clearly right in the middle between Clovis and Solutrean and what's really exciting about it is that the technology here is very similar to Solutrean. In fact it's closer to Solutrean than Clovis where you can see that it's in a progression between Solutrean and Clovis so you have Solutrean, Cactus Hill and Clovis.

NARRATOR: The evidence of the points was that there was no 5,000 year gap. The Solutreans hadn't disappeared. They seemed somehow to have gone from France to America some 16,000 years ago, but it was still far from proof. Critics pointed out a massive problem, one that was 5,000 kilometres wide: the Atlantic Ocean. How, they asked, could a Stone Age people have made a journey that was thought to be beyond mankind until thousands of years later? The fact was the Solutreans lived in south-west France. Between their settlements here on the coast and America lay one of the biggest expanses of water in the world and there was something that made the journey far more formidable then: the Ice Age.

BRUCE BRADLEY: The environment would have been pretty much a frozen environment similar to what we see in the Arctic today and the ice was the furthest south that it, that it ever got. The environment would have been almost diametrically opposed to what we see here today. We wouldn't see people lounging on the beach.

NARRATOR: At the time of the Solutreans ice-sheets stretched down from the Arctic obliterating life as far south as southern France. The weather, even in south-western France, would have dropped to 20 degrees below freezing. The Atlantic would have been thick with icebergs and over-run with blizzards. It is difficult to conceive of a journey to America through this.

LAWRENCE GUY STRAUS: There are 5,000 kilometres of open North Atlantic Ice Age conditions to be crossed. There are icebergs floating around in the Bay of Biscay and it's a polar desert.

NARRATOR: The problem confronting Bradley and Stanford was to show how the Solutreans could have survived these extraordinarily harsh conditions. Could this Stone Age people have used their technology to take them across an ocean? How would they have travelled, kept warm and found food? There was one place on Earth where Stanford hoped he could find out, from the one people on Earth who still live in conditions like those endured by the Solutreans: the Eskimos. Stanford flew to Alaska, to the small town of Barrow. Barrow stands on the edge of the continent at the northern most tip of the United States. Here people have to endure temperatures that reach below -35°C in the winter. Nowadays they live a thoroughly modern existence, with supermarkets, four-wheeled drives and snowmobiles, but Stanford hoped that ancient Eskimo techniques might demonstrate how much the Solutreans could have achieved with their inventions thousands of years ago.

DENNIS STANFORD: I'd like to show you some old needles. This needle is 20…

ESKIMO WOMAN: Needle. (Yeah) Oh.

DENNIS: 20…

WOMAN: Eskimo needle.

DENNIS: No, 20,000 years old.

WOMAN: Ah that 20,000…

NARRATOR: The Solutrean needle was almost identical to Eskimo ones, made of bone and used until recently. The Eskimos used these needles to fashion warm, waterproof clothing out of fur.

ESKIMO WOMAN: Eskimo mukluks. This way and this way and this way and this, that way.

DENNIS STANFORD: To make a waterproof seam.

WOMAN: They use… Yeah, waterproof.

DENNIS: Right.

NARRATOR: The Eskimos used caribou skin and sinew to make their clothing. The Solutreans could have hunted the same animals and they would have had exactly the same function. That needle would have been their passport to survival in the Ice Age landscape. It would have allowed them to keep warm and dry. Even so, their survival was far from certain in this polar desert. What would they have eaten on a voyage which would have taken months? Again the Eskimo has provided the answer. There is all the food anyone could want - in the sea.

RONALD BROWER (Inupiat Heritage Centre, Barrow): The sea has been our garden. We don't have any growth, growing things. There's nothing growing up here, so we depend on the sea for our livelihood and most of our hunting is based on sea mammal hunting. We have the great whales, polar bears, walrus, seals and fish and this is a good time for us to be going out to do some crabbing, for example.

NARRATOR: What Stanford realised was that the Solutreans could have done exactly the same. They had all the tools they needed to hunt at sea, from spears to bows and arrows. Above all they had the crucial Clovis Point.

DENNIS STANFORD: The projectile points that we found that are Solutrean in age are almost identical to the in blades that Eskimos use on their seal hunting harpoons and the Clovis Point makes a wonderful harpoon point. The technology's there, the technology is definitely there.

NARRATOR: But then came the critical question: how would they actually have travelled, could they have made boats capable of surviving journeys across thousands of miles of icy water? It would be easy to assume that Eskimos today would rely on the most modern craft when going out to sea, but in fact this isn't the case.

RONALD BROWER: You need something resilient here and these advanced technological materials do not work well in the Arctic. They freeze, they break. Unbreakable plastic breaks apart.

NARRATOR: Instead Eskimos still build their whaling boats with sealskin, wood and caribou sinew. The frames are sealed with oil applied directly from seal blubber. These are exactly the type of materials that would have been available to the Solutreans.

DENNIS STANFORD: People have been using this type of craft for at least 10,000 years that we know of and probably 20,000. The flexibility of this type of, of boat is, is really amazing and it's specially built for Arctic waters.

NARRATOR: 17,000 years ago the Solutreans had all the materials and the skills they needed to build Eskimo-style boats and what Stanford discovered is that the flimsiness of these open boats is deceptive. Once launched into the water these craft are capable of making extremely long journeys through the ice.

DENNIS STANFORD: Boats like these can, could have made the journey that we're hypothesising for Solutrean people quite well. In fact I was noticing on the distance signs here in the middle of town they say it's about 1500 miles to Greenland and we know that prehistorically Eskimo peoples moved that distance from here to there several times.

NARRATOR: The way Eskimos travel is to work along the edge of the ice hopping from ice floe to ice floe. 17,000 years ago the northern Atlantic, as far south as south-west France, would have been filled with pack ice and the Solutreans would have been able to travel in the same way.

DENNIS STANFORD: Well it certainly is exactly the way I think the Solutrean guys were dealing with the ice edge 'cos you can get in and off of the ice real rapidly and, and if the weather gets a little, little nasty then you just pull up off the, out of the water and onto the ice. Operating along the edge of the ice like this you could keep hitting the water all summer.

NARRATOR: Stanford and Bradley felt the Eskimos had greatly strengthened their case. The Solutreans had everything they needed to make a journey like this and to the Eskimos the proposed feat of these Stone Age people would not be at all out of the ordinary.

RONALD BROWER: There's nothing that would have prevented other people from crossing the Atlantic into the Americas 17,000 years ago. It, it would be a perfectly normal situation from my perspective.

BRUCE BRADLEY: Why not a journey like this? I mean I'd turn the question around. It's not could they have done it, is how could they not have done it?

NARRATOR: But however convinced Stanford and Bradley were that the Solutreans were capable of this epic voyage their critics would need something stronger and then, completely by chance, a remarkable piece of new evidence emerged. Back in America, Douglas Wallace was continuing his mammoth task of writing the history books according to the evidence of DNA. So far his work showed that the Native Americans had four distinctive types of mitochondrial DNA - A, B, C and D - all of them from Asia. Then one day a set of samples from a north-eastern Native American tribe called the Ojibwa arrived on his desk.

DOUGLAS WALLACE: When we studied the mitochondrial DNA of the Ojibwa we found, as we had anticipated, the four primary lineages - A, B, C and D - but there was about a quarter of the mitochondrial DNAs that was not A, B, C and D.

NARRATOR: There was a mysterious fifth source of DNA. He called it X, and X was very strange. It was of European origin. At first he thought it must have got there some time in the last few hundred years, after Columbus.

DOUGLAS WALLACE: When we got that result we naturally assumed that perhaps there had been European recent mixture with the Ojibwa tribe and that some European women had married into the Ojibwa tribe and contributed their mitochondrial DNAs.

NARRATOR: But he was wrong. When the dates of X came back it was dated thousands of years earlier, some 15,000 years in fact, the time of the Solutreans.

DOUGLAS WALLACE Well what it says is that a mitochondrial lineage that is predominantly found in Europe somehow got to the Great Lakes region of the Americas 14,000-15,000 years ago.

NARRATOR: It seemed there could now be no doubt. Some of the earliest Americans were really from Europe. The DNA proved it and so it is now possible to tell a quite different story about the first settlement of America and one which makes sense of all the evidence. The Ice Age led not to one, but a whole host of migrations to America as people fled the frozen wastes in search of something better and one of these groups, perhaps the most important of all, was an extraordinary people from Europe.

BRUCE BRADLEY: For me the, the most important aspect of our theory about people leaving south-western Europe and eventually ending up in North America is that I, I think it takes into consideration the abilities of people to adapt to new environments, to embrace new places and to ignore the, this possibility ignores the humanity of, of people 20,000 years ago.

NARRATOR: It was a journey that would have seen them hopping from ice floe to ice floe, spearing food out at sea, huddling together to keep out the fierce cold. Eventually they would have arrived at the rich fishing grounds at the edge of a new continent. There some of the Solutreans settled and helped build an enduing culture that spread across the continent and transformed the landscape of America. Though controversial, this discovery may not be so upsetting to Native Americans after all.

JOALLYN ARCHAMBAULT: I think the value of this research is that it shows that we are truly all one species and that our ancestors tends of thousands of years ago were very much like us and they had new ideas and that they did crazy things in small boats crossing big bodies of water to go somewhere else. I mean I think that's marvellously creative and courageous.

NARRATOR: As humanity moved inexorably across the planet this great voyage of the Solutreans to settle a new world has emerged as one of the last great colonising efforts of our species.


 
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