Neanderthal Man (23 page)

Oddly, the fact that the Vindija Neanderthals were cannibalized, or at least de-fleshed, by other Neanderthals may be responsible for the fact that we had found rather a lot of Neanderthal DNA and relatively little bacterial DNA in at least some of the Vindija bone fragments. If the Neanderthal corpses had been buried, months would have passed before all its soft tissues were consumed by bacteria and other microorganisms. There would thus be ample time for bacteria to penetrate the bones, degrade the Neanderthal cells and their DNA, multiply, and eventually die themselves. Extracting DNA from such a bone would mostly yield DNA of microorganisms. If, on the other hand, the Neanderthal had been butchered, the bones crushed, gnawed, and sucked free of any meat and marrow before being tossed aside, some bone fragments would quickly dry out, limiting the chance for bacteria to multiply in them. Thus, we might have Neanderthal cannibalism to thank for the success of retrieving DNA in some specimens from Vindija.

All this went through my head as I looked in the box containing bones so crushed that it was impossible to tell whether they came from animals or Neanderthals. I turned to Dejana Brajković and asked if we could at least sample some of these fragments, whose source was so ambiguous. I argued that if DNA were preserved in them, we could determine what species they came from. But Brajković was adamant; we could not touch any of the bones. She said she had heard that in a few years one would be able to hold a sensor close to a bone and thereby determine its entire genome sequence; thus it was inadvisable to sacrifice even a tiny part of a bone fragment now. I agreed that techniques would certainly improve in the future but expressed polite doubt about whether we would live to see the advance she envisioned. Again, I suspected the influence of powers greater than hers. I said we would discuss our needs with the Croatian Academy and be in touch.

In the afternoon, we visited Jakov Radov
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at the Museum of Natural History. He appeared to be supportive of our project but expressed grave reservations about the sampling of any bones in either the Krapina or Vindija collections. I was sure we had not yet gotten to the bottom of things, and in a gloomy mood we returned to our small and scruffy hotel room. I lay on  the bed, gazing at the paint peeling from the ceiling and feeling completely frustrated. As far as I knew, these were the bones containing the best Neanderthal DNA in the world. Many of them were of little or no morphological value, so fragmented that you couldn’t even tell whether they came from a Neanderthal, a cave bear, or some other animal. Yet some unknown person with influence over the people at the institute was apparently determined to make it impossible for us to work on them. Like a child denied his favorite candy, I felt like screaming and kicking, but my Swedish upbringing kept me from venting in such an obvious way. Instead, Johannes and I spent the evening in a bad restaurant around the corner from our hotel, brooding about our mysterious enemy.

The next day I gave a talk before the medical faculty of the University of Zagreb about ancient DNA in general and our Neanderthal work in particular. It was well attended, and many of the students asked questions. It cheered me a bit that some young people in Zagreb were enthusiastic about science. In the evening, we had dinner with Pavao Rudan, a professor of anthropology at the university, who stems from an old family of landowners on the beautiful island of Hvar, off the Adriatic coast. He invited us to join him and his colleagues at a restaurant named Gallo, which turned out to be one of the best restaurants I have ever been to. Course after course of excellent seafood and creative Mediterranean dishes were served, along with good wines. The meal was rounded off by a wonderfully refreshing drink of fruit juice, champagne, and some other ingredient that I couldn’t make out. I felt slightly better. Then, Pavao started to talk about science. As it happened, my conversation with him was to improve my spirits in a much more lasting way than the exquisite dinner.

First, we talked about his work on small human populations on the Croatian islands. He was trying to find genes and lifestyle traits that contribute to common disorders, such as high blood pressure and heart disease. For many years, he had had grants from the United States, France and the UK for this project, which testified to his scientific credentials. I figured that he would recognize a good project when he heard about it, so I talked at length about our plans and our problems. Pavao listened to my plight with sympathy and was willing to help. Crucially, he knew how to navigate the Byzantine politics of Croatia. He told me that he had just been elected to the Croatian Academy of Sciences and Arts and would soon be inducted as a member. He suggested that we approach the project not just as  a collaboration between our research group and the Zagreb institute where the Vindija collection was housed but as a collaboration between the Croatian Academy and another academy—that is, one I belonged to as a member.

I was in fact a member of several scholarly academies. Such memberships are honors that I had until then regarded as quite irrelevant to my everyday science. I never attended their meetings, having imagined that they consisted of earnest discussions attended by esteemed scientists well into their dotage. But now they suddenly seemed important. Which academy should we approach? I suggested the National Academy of Sciences in the United States, perhaps the most prestigious academy membership I held, but Pavao advised against it. He suggested we should rather approach some academy in Germany. We settled on the Berlin-Brandenburg Academy of Sciences and Humanities, of which I had been a member since 1999. He suggested that I approach the president of the Berlin Academy and ask him to write to the president of the Croatian Academy to propose our project as a collaboration. He also advised me to wait a few weeks, until he had been inducted into the Croatian Academy. Along with other sympathetic members, he could then put in a good word for the project with its president.

The next morning, Johannes and I flew back to Leipzig. I was feeling a bit more optimistic. We didn’t have the bones with us, as I had hoped, and persuading the Croatian Academy that it would be in the best interests of science to work with us remained a challenge. But with the help of Pavao, we might have a chance.

Back home, I immediately phoned Günter Stock, president of the Berlin-­Brandenburg Academy. He listened intently and was ready to help; he liked the idea of strengthening ties with Croatia. With the help of his assistant for foreign relations, I drafted a letter from him to the president of the Croatian Academy, proposing the Neanderthal Genome Project as a collaboration between the two academies. We also suggested that we would be willing to support the establishment of a catalog of the Vindija collection, by donating a computer and resources for someone to do the work.

But I didn’t leave it at that; I wanted to do everything I could to overcome the mysterious resistance in Zagreb. One way to do this would be to involve all relevant parties there in the project. So I wrote to Jakov Radovčić
and invited him to the upcoming July press conference with 454, suggesting that he present the paleontological aspects of Neanderthals to the press. He responded that he had other obligations that made it impossible for him  to attend. I also contacted Frank Gannon, director of EMBO, the European Molecular Biology Organization, to which I also belonged, and asked him to contact Dragan Primorac, the Croatian minister of Science, Education and Sports, on our behalf. Dragan Primorac is an unlikely politician. He is a professor of forensic science at the University of Split in Croatia as well as an adjunct associate professor at Penn State University in the United States. Dragan, who has since become a friend, answered that he would put in a good word for our project with the academy. I had no idea whether all these initiatives would help our project, but I wanted to leave no stone unturned.

In the meantime, the letter from Professor Stock on behalf of the Berlin-­Brandenburg Academy formally proposing the Neanderthal project, as well as a letter from me, had arrived at the academy in Zagreb. Pavao Rudan, asked by his colleagues for his opinion, suggested some conditions for the proposed collaboration: at least one Croatian co-author should appear on all papers we were to publish on the Vindija material, the Croatian Academy should be mentioned in the acknowledgments, and at least two scientists from Croatia should be invited to Leipzig each year as long as the project lasted. I agreed to these conditions and added that we, along with the Berlin Academy, would support the establishment of a catalog of the Vindija collection.

All this took time. Summer turned into fall, and fall turned into winter. I was meanwhile pursuing other promising Neanderthal sites, concentrating on places where our previous work had shown that DNA was preserved. The first and most obvious one was the Neander Valley site itself, where the type specimen had been found in 1856. At that time, the cave had not been scientifically excavated but was emptied out by quarry workers, who collected bones as they happened to notice them. Since then, the entire cave, as well as the small mountain where it was situated, had been quarried away for limestone. Frustratingly, many of the bones of the type specimen had never been collected. Some years earlier, Ralf Schmitz, with whom we had worked on the type specimen, had had the crazy but brilliant idea of trying to find the missing bones. After painstaking investigation of old maps, long walks in Neander Valley, and the exercise of a great deal of intuition, he had managed to find the place, then partly under a garage and car-repair shop, where much of the cave debris had been deposited 150 years ago. He began an excavation, and his efforts paid off handsomely in  that he found not only fragments of the type-specimen individual but also bones from a second individual. In 2002, we retrieved mtDNA from this individual and published it with Ralf.
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Now Johannes returned to the bits of samples we had left and did new DNA extractions, analyzing them with our new methods to look for nuclear DNA. The results were discouraging. The extracts contained between 0.2 percent and 0.5 percent Neanderthal DNA—not enough to sequence the genome.

Another site, Mezmaiskaya Cave in the northwestern Caucasus, had been excavated by an archaeologist couple, Lubov Golovanova and Vladimir Doronichev, who were based in St. Petersburg, Russia. They had found remains of a small Neanderthal child. This child had probably been deliberately buried, and not consumed, as all its bones were intact and found in their expected positions. An exciting aspect of this child was that while the Neanderthals we had analyzed up to that point were all about 40,000 years old, this baby was between 60,000 and 70,000 years old. Lubov and Vladimir had visited our institute, bringing with them a small piece of a rib from the child for us to analyze, and also a fragment of a Neanderthal skull found in a higher layer of the cave. When Johannes made extracts from these specimens, the rib turned out to contain 1.5 percent Neanderthal DNA. This was still not as much as we had hoped for; moreover, the rib was so tiny that we could never hope to get enough DNA for a genome sequence from it. But it might contribute some data to our efforts.

The third site we explored—El Sidrón—was in Asturias, in northwestern Spain. I visited it in September 2007. When a child dreams of becoming a paleontologist, this is the type of site he or she imagines. El Sidrón is located in beautiful countryside. The cave entrance is small and hidden, and the cave has served as a refuge for people throughout the ages. In front of the entrance is a memorial to a fighter who hid there during the Spanish Civil War and was killed by the fascists. After crawling through the entrance, one walks about two hundred meters to a side gallery, twenty-eight meters long and twelve meters wide, on the right. There, Professor Marco de la Rasilla of the University of Oviedo and his collaborators and students excavate every summer. They have found bones from one Neanderthal infant, one juvenile, two adolescents, and four young adults. The long bones were crushed and full of cut marks. Only the bones of the hands were found  together; they had been separated from the bodies and thrown to the side. Marco de la Rasilla believes that the body parts were disposed of in a small pond on the surface some 43,000 years ago and then washed into the cave.

New bones were being discovered at this site each summer, and we agreed that they should be collected for DNA analysis in ways that would maximize DNA preservation and minimize the chance of contamination by present-day human DNA. Working with Carles Lalueza-Fox, a molecular biologist at the University of Barcelona, and Antonio Rosas, a physical anthropologist at the National Museum of Natural Sciences in Madrid, the excavators equipped themselves with sterile gloves, clothing, face shields, and other tools typically used in our clean room. When they came across bones deemed suitable for DNA extraction, they donned the sterile outfits, removed the bones, and placed them directly in an icebox to freeze them. Back in Antonio’s lab in Madrid, computer tomography of the bones was performed to document their morphology. The bones were then sent, still frozen, to us in Leipzig. Almost no one had touched them since their discovery, and bacterial growth would also have been minimized. I had high hopes that when Johannes made extracts, they would contain a lot of Neanderthal DNA, but of all the DNA in the bones, just 0.1 to 0.4 percent came from Neanderthals. From none of these sites, nor several others that we tried with even less luck, did we find enough DNA for a Neanderthal genome sequence. Vindija Cave was the only site where we had so far found a bone that had anywhere near enough DNA. Yet in Zagreb, things moved at a glacial pace, if at all.

One bright spot, late in the summer of 2006, was the arrival of a talented Croatian graduate student, Tomislav Mari
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, in our group. Tomi had accompanied us when we visited the Institute for Quaternary Paleontology and Geology, and his cultural connections with Croatia came in handy as we tried to reach an agreement over the Croatian Neanderthals. Our project had become a matter of public debate there—a debate I could follow thanks to Tomi’s translations of the Croatian newspapers. In July, after we had announced the Neanderthal Genome Project at the press conference in Leipzig, one of the big dailies,
Jutarnji List,
interviewed Jakov Radov
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, who was described as someone “without whom no Neanderthal research can be imagined.” Said Jakov: “The question is: What is the goal of the research? Also, it is still not clear that one can retrieve the whole Neanderthal genome. . . . They are using a chemically aggressive method which destroys the material, which is too precious for us to sacrifice.” In November the same paper quoted him again: “Three and a half months ago, Svante Pääbo  was in Zagreb looking for more samples for his molecular genetic analysis. . . . However, I think we should take special care of the samples and keep them safe, so the next generation of researchers can use them.”