The ancient man fascinates. For example, what about the Neanderthal from the Netherlands? And in Europe? And what new insights await us? Former Spinoza winner Wil Roebroeks answers twelve burning questions.
Humanoids probably roamed this part of Western Europe just under a million years ago. Remains of these hominids may be buried under a thick layer of sediments in the bottom of the North Sea. Only with a new glacial, far in the future, when the North Sea will dry up again, will this archaeological archive become available.
However, with the sand extraction in the North Sea for the Second Maasvlakte, among other things, fossils of early humans are already sporadically surfaced, such as the skull roof of the Neanderthal, which was named 'Krijn', which was found in June 2009. This interview with Wil Roebroeks, professor of Archeology at the University of Leiden, is about early hominids in our country and the archeology of the North Sea.
How old are the oldest European hominin fossils?
They are between 800,000 and 1.2 million years old. Fossils of 1.7 to 1.8 million year old hominins have been discovered just outside Europe, in Georgia1 . The oldest remains in the Netherlands date from about 300,000 years ago. These are stone tools that were found in South Limburg. But what we could potentially find here is expected to be two to three times as old. In England, the oldest traces of hominids are dated to about 800,000 years.
The fact that those tracks have been found there and not yet here has to do with the fact that a large part of the Netherlands is a subsidence area. The deposits are often simply so deep that we cannot reach them. The Pleistocene only appears on the surface in our country in the south and east, but this generally concerns small outcrops of sand and gravel layers.
On the east coast of England, in Norfolk, we are lucky that the tracks are not in, but on the edge of the North Sea basin. Deposits from the primeval Thames, for example, are accessible there at current sea level, while deposits of a comparable age along our coast lie tens of meters below the seabed; if they have been preserved at all. In England the deposits are well preserved because there is a thick layer of boulder clay over the Pleistocene sediments.
Can we call Krijn – the Neanderthal found in the North Sea in 2009 – the 'first Dutchman'?
There has been a constant coming and going of people throughout history, and more importantly, a constant changing of the land-sea division. I don't think it makes much sense to talk about the 'first Dutchman'. From the perspective of prehistoric times, we are all immigrants. Forty thousand years ago the Neanderthals lived here, which has made way for the Homo sapiens . Based on DNA analysis, we now know that the first farmers, who settled here 7,000 years ago, were not related to the local hunter-gatherers who lived here at the time.
Could Krijn have been brought in from elsewhere via ocean currents?
During large parts of the Pleistocene, the current North Sea was simply dry land. This piece of skull probably only came into contact with seawater for the first time when it was sucked up by the shell sucker. Before that time it lay in a river deposit covered with sand and gravel layers. This individual must have died somewhere between 80,000 and 40,000 years ago on the banks of the early Rhine.
As the river shifted its course to the north, sand dunes crept over it. The fossil had been in a dry area all along, until about 8,000 years ago the country was inundated by the emerging North Sea. The amateur archaeologist who collected the fossil knew in which area the piston was working. Such a ship has a concession for a certain area. For example, we know with an accuracy of a few square kilometers where the skull fragment was sucked up. Geologists have determined from which ancient riverbed the skull originated.
How can you tell that it is a Neanderthal?
We are very lucky that it is a piece of skull, part of the forehead with eyebrow arch. From a piece of femur or the side of a skull it would have been very difficult to determine which hominin it came from. The eyebrow arch of the Neanderthal is very characteristic. The Max Planck Institute for Evolutionary Anthropology in Leipzig, this skull fragment has been compared with dozens of scans of various skull shapes and has thus been able to determine with great certainty that it is a Neanderthal. It must have been a young individual, because the sutures of the skull are not fully grown.
The fossil is now on display at the Museum of Antiquities in Leiden, but remains the property of the finder, a Belgian collector. There is a good chance that there are more pieces of Neanderthal bones in collections at people's homes that have not been recognized as such.
What was it like for you to hold the fossil of the 'Dutch' Neanderthal in your hands for the first time?
I remember being quite moved. At such a moment you have physical contact with a being that walked on the North Sea plain a long time ago. It's a kind of relic. What makes this fossil extra special is that it shows so clearly that we as archaeologists are missing a huge area of research.
Until 10,000 years ago, the world's land area was much larger than it is today because a lot of water was locked up in the ice caps. Close to home the North Sea bed was dry; further afield, for example, Australia, New Guinea and Tasmania formed one entity. Huge areas, many times larger than the Netherlands, are currently inaccessible to archaeologists. After the current warm period – in roughly 10,000 to 20,000 years – when the ice sheets have grown again and a new glacial starts, these areas will dry up again and become accessible for archaeological research.
How important are amateur archaeologists in your field?
These are extremely important:they are the eyes and ears of the profession. There are amateurs who could work as teachers at university. In our research in England, some amateurs are co-authors of scientific papers. The finder of the Neanderthal fossil, Luc Anthonis, is also listed as a co-author in the Journal of Human Evolution .
I myself started as an amateur. I was born in South Limburg, where it was bursting with geology and archaeology. When I was 10 years old, I carved belemnites and other fossils from the Limburg limestone together with my brothers. From that same limestone, farmers cut flint 6000 years earlier to make axes and other tools.
When I was little, excavations were done in our neighborhood by the University of Groningen . I saw excavators and huge potholes. I loved that people had lived in my hometown thousands of years ago. It was difficult not to get infected with this hobby.
Yet you went to study history…
Yes, modern history with a specialization – entirely in the spirit of the times – social and economic history. But I have always remained active as an amateur archaeologist. After my master's degree in history I started studying prehistory; the blood was creeping…. That study also included a large subsidiary subject Quaternary Geology.
At that time – we are talking about the late 1970s – you could take any secondary subjects you wanted, such as Aboriginal anthropology, and hunter-gatherers like early humans. I now realize that wide choice of secondary subjects was an enormous luxury. You just did that, whether you got credits for it or not.
Already during my studies I was mainly interested in the early phase, the archeology of the hunter-gatherers from more than 10,000 years ago, so everything from pre-agricultural times. In the Netherlands, hardly anyone was doing this professionally at the time, which made it extra fun. I am currently working on a project about the Tasmanian Aborigines, who until a few hundred years ago lived about the same as European hunter-gatherers in the last glacial.
If you get a cash prize again2 would receive, which research would you give priority to?
Then I would like to expand the research on the English east coast and take that as a starting point to better tackle the entire North Sea basin. The Netherlands does scandalously little about the archeology of the North Sea. Little is known, especially about the southern part of the North Sea, because there is little oil and gas there. The Maasvlakte that is now being reclaimed offers enormous opportunities. It is a project that involves a lot of money, but only a very small amount goes to archaeological research.
Such a large area as is now being developed here is unprecedented for the Netherlands. The quarry created here by suction work is large, think of a few thousand football fields and then ten meters deep! Guidance from archeology is almost entirely lacking. Archaeological preliminary research is now mandatory on land locations.
Before you dig such a quarry in the sea, you should determine which strata are there and of what age they are. We now only have a very coarse model of the North Sea bed that only 'predicts' at what depth certain layers occur. This model should be further refined and the opportunity is now here. There is now more drilling because the sand extractors want to know where the gravel and sand layers that are of interest to them are located. We would like to see additional boreholes drilled to map the area in detail and to date the strata using pollen content, snails, rodent remains and other well-dated fossils.
Why isn't this happening?
The problem lies mainly with the archaeologists themselves. They do not see the importance of the older periods. In the view of many archaeologists, those 'hairy monkeys' do not fall within their field of cultural heritage. The service responsible for this, the Cultural Heritage Agency , has not always been so committed to the older periods. That interest comes gradually, but very slowly. The government should declare that the period of the Neanderthals also belongs to our cultural heritage.
Let's take an example of the English, who say:"Everything is archaeology". In the reconstruction of early landscapes, the English want to collect knowledge about those landscapes in all epochs, whether that is 10,000 years or half a million years ago. Even if there were no humans and only prey animals, such an area is interesting because that situation also requires an explanation that is archaeologically relevant.
It is therefore no coincidence that you are doing research in England…
It is not only more interesting geologically there because the layers are so easily accessible, but above all it is much easier to work there. In England you can still improvise an incredible amount, while in the Netherlands a lot is brokenly regulated. The problem with many Dutch projects is that you need to know now, so to speak, what, where and how you are going to excavate in three years' time, while in English projects you can constantly adjust your research question.
What new insights about prehistoric man are waiting for us soon?
I think that Neanderthal will be included in the species of modern man in the foreseeable future. Instead of Homo neanderthalensis will he then Homo sapiens neanderthalensis to be named. We owe this insight, among other things, to DNA research of Neanderthal fossils.
Even more exciting, DNA analysis of a hominin bone remains from the Denisova Cave in Siberia shows that a hominid lived here that is just as closely related to us—modern humans—as to Neanderthals. It is a primeval man that we only know because of its DNA signal and not because of its skeletal shape. This new "species" - the Denisovan - probably walked the Earth for a very long time, between half a million and 30,000 years ago. The idea is now that half a million years ago Neanderthals arose in western Eurasia and Denisovans in eastern Eurasia.
We know that all humans outside of Africa carry Neanderthal genetic material. When modern humans left Africa sometime between 100,000 and 50,000 years ago, they mixed with 'local' primordial humans, such as the Neanderthal and the Denisovan. So you can say that Asians and Europeans are genetically more similar to Neanderthals than Africans.
In archeology we have always said that Neanderthals and Homo sapiens were similar in important aspects of their behavior, as evidenced by excavations of simple tools from both groups. Recent DNA research confirms that a small population of Neanderthals has been absorbed into a much larger population Homo sapiens .
And can we expect another revolution in archaeology?
In my opinion, that will be a technical one from the field of molecular biology. I expect a lot from the integration of classical methods and high-tech natural sciences. I think that much can be gained in the exchange of knowledge between the two disciplines.
A nice example is that we as archaeologists are increasingly being consulted by a new branch of medicine:evolutionary medicine. Researchers in that field are increasingly interested in the diet of early humans. Their idea is that some of our diseases of affluence, such as cancer, obesity and cardiovascular disease, stem from the fact that our bodies are designed for a different type of environment, climate, activity and food supply. Consider, for example, lactose intolerance:a large part of the adult world population becomes ill from drinking milk. The ability to digest milk as an adult only started a few thousand years ago, DNA research has shown.
The Max Planck Institute for Evolutionary Anthropology is able to reconstruct the diet of the Neanderthal on the basis of proteins from bone material. Previously, as archaeologists, we were dependent on the scarce food remains at the site of the encampments. Fire is also such an interesting subject for both disciplines. Some archaeologists believe that fire was discovered several million years ago; others think of a quarter of a million years ago. The latter would mean that humans have eaten raw products for much longer.
1 In the Gea of March 2010 (p. 3-7) an article is devoted to the Dmanisi skull from Georgia.
2 In 2007 Wil Roebroeks received the Spinoza Prize, a Dutch cash prize (to be spent on research) that is awarded annually to top researchers who are pioneering and inspiring in their field.