Svante Pääbo studies DNA preserved in the remains of ancient organisms and what it can tell us about human evolution. NOMIS supports his investigation of the changes that occurred in human proteins involved in the development and function of nerve cells during the past half-million years. This project is a crucial first step toward understanding the genetic underpinnings of what makes modern humans unique.
Svante Pääbo is a NOMIS Distinguished Scientist Awardee and the director of the Department of Evolutionary Genetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. We spoke with him about his career and about how he creates a unique working environment in his group.
NOMIS: You were still a PhD student when your research was published in Nature. Did this early success trigger your interest in a research career?
SP: I do not think that success per se was important. What was crucial was rather my fascination with ancient history and Egyptology. This meant that when I got into molecular biology it seemed natural to apply this to ancient remains, which I knew were lying around in museums.
NOMIS: Your mother was a scientist; did this influence you?
SP: Growing up with my mother, who was a chemist, instilled in me a feeling that research is cool and interesting. That surely influenced me.
NOMIS: Other scientists have referred to you as a role model with respect to team-leading. Do you know why?
SP: [Laughs] You should ask my team if this is really true…
NOMIS: But how do you create a productive research environment?
SP: I — like everyone else — want to have fun. I want enjoy being at my workplace and want to work with people who also have fun. That is not always possible, but we try to create an environment where one can have a good time.
NOMIS: What are your criteria for selecting candidates to be on your team?
SP: We try to involve the group in all decisions, including the decision about who gets hired. When we recruit students, postdocs or group leaders, they get to talk to almost everybody. After that, we discuss how the candidates would fit in scientifically as well as socially. It is very important that people get along, because it is only in an environment in which you feel safe and at ease that you dare to express crazy ideas — there is nothing more stifling than fear.
NOMIS: What about grades — are they informative to you?
SP: Someone who has perfect grades in every subject makes me a little suspicious — not that we would refuse to interview someone like that, but I would want to explore whether they have passions or interests. Someone who is very good in certain subjects but perhaps mediocre in others is more what we may look for.
But above all, it is important that somebody can explain, for example, what they did in their Masters thesis. Do they think critically about it? That is much more important than if they have been lucky with their project and produced a fancy paper.
It is also important that they have thought about what we are doing, and perhaps even propose experiments that could be done — even if these are things that an insider knows are not realistic.
NOMIS: Was your environment supportive of you in terms of pursuing your research?
SP: At the time when I was working on my PhD, it became obvious that one could address a lot of evolutionary questions by applying the then-new techniques of cloning DNA in bacteria to present-day organisms. One could, for example, find out how different species were related to each other. To me, it was very tempting to try to “go back in time” to see what DNA sequences were around thousands of years ago. But I was not sure that my PhD supervisor would be supportive of this, so I initially kept it secret. Nevertheless, the environment was certainly supportive in that there were enough resources around to try crazy things like this, things that had only a remote chance of success.
NOMIS: In retrospect, what was the most difficult period of your research career?
SP: The preservation of DNA from ancient mummies and other dead organisms quickly led me to believe that we could address all kinds of interesting questions. But then came the realization that many of the DNA sequences that were retrieved, including those first sequences from an Egyptian mummy, which I published, came from present-day human DNA in the environment, and not from the ancient organisms. For example, our group showed that if you extracted DNA from an ancient mammoth or cave bear, you could almost always get human DNA from it, and only rarely elephant-like or bear-like DNA. This human DNA came from museum keepers, from archaeologists or from ourselves.
For a number of years we thought that any work on ancient DNA would have to be restricted to extinct animals, because in these cases human DNA contamination could be easily recognized as such. That was disappointing to me as I was really interested in human history and human evolution. Fortunately, this changed when new techniques were developed. And over the past ten years, it seems that all my wild dreams from 30 years ago are coming true.
NOMIS: Do you think that your research influences current paradigms within philosophy or social science?
SP: “Paradigm” is a grand word. I leave that to others… Perhaps the fact that Neandertals contributed genetically to present-day humans has influenced how people think about Neandertals. Yet, how people speculate about the interaction between these two forms of humans says much more about the person speculating and almost nothing about what happened tens of thousands of years ago. Some would view the disappearance of Neandertals as the first genocide committed by modern humans; others would focus on what was perhaps peaceful coexistence for many thousands of years. What really happened, we do not know.
NOMIS: As a scientist you are constantly pushing the envelope. Does this in any way reflect a personality trait? Are you a risk taker?
SP: As a scientist you are, in my opinion, an extremely privileged person: You are paid a salary for playing around with ideas you find interesting — it is amazing. So what we do is not really “risk taking” in my mind. But many scientists who open up new fields may perhaps have a certain irreverence for the received wisdom. Maybe they even take a delight in questioning what everyone else believes. They may have a certain disrespect for authority.
This interview was conducted by Cosima Crawford on Feb. 15, 2017.