“I strive to maintain the romantic spirit of palaeontology amidst so much technology”
Palaeontologist Juan Luis Arsuaga, co-director of the archaeological site of Atapuerca, recently visited the UAB to give a conference at the Faculty of Biosciences in celebration of its 10th anniversary.
![Juan Luis Arsuaga](/Imatge/929/873/EntrevistaArsuagaG.jpg)
- We should focus on when our ancestors left Africa and spread throughout Eurasia, because Europe is not separated from Asia geographically. One of the natural frontiers we can consider is the Caucasus mountain range, where human fossils dating back two million years were found to the south of the Caucasus, in modern day Georgia. That is when the human expansion outside of Africa took place, we changed continents and at least at that moment humans were prepared to penetrate into Europe. When did the expansion into Europe and even into Asia occur? It started at the part of Eurasia closest to Africa more than 1.8 million years ago, and the oldest fossils we have can be found in Atapuerca and they date back some 1.2 million years. Archaeological sites also exist from that same time period in Orce, Granada, so we can say that has been a broad presence of humans in the Iberian Peninsula since at least 1.25 million years ago, and maybe a little more. And that is when humans occupied Europe. We do not know if it was continuous, because we still need more fossil registers, but there has been human occupation up to the present. There may have been periods, however, in which humans disappeared, or maybe there were successive waves of humans entering Eurasia. These are all the things we still need to establish.
- What discoveries do you consider have been most important at Atapuerca?
- What is best about Atapuerca is that it has a set of sites with a very broad registration of fossils from a vast period of time. Moreover, human fossils have been found from different time periods. It is rich in human fossils, which is what makes it very exceptional, because this is seen in very few sites, and it also contains fairly continuous information on the evolution of humans in Europe. So we've been able to report about the first European inhabitants up until the arrival of metallurgists or farmers and herders. In other words, the human populations which inhabit Europe today. Something which is not so well-known, for example, is that Atapuerca is a site from which we make significant contributions in palaeogenetics to the genetic history of today's European populations, in recent periods previous to the Romans. With this I mean that the ability to study and publish results ranging from the arrival of agriculture and livestock farming, or the Bronze Age, and go all the way back to the European settlements 1.2 million years ago is what makes the Atapuerca site unique.
- How have scientific advances contributed to your field of study?
- My discipline, which is palaeontology, has become so technical that I am starting to not like it. There is obviously an intellectual part and somewhat of a mechanical part, but today we also use the latest technology. Therefore, it is a very technological profession, even if what comes to mind is that palaeontologists and archaeologists are people who use very simple tools when working. However, this is not true because scans are taken continuously of the site and the latest digital technologies are used to register the objects, highly detailed topographic maps are made: all the available digital technology is applied to the excavations. And later, the materials are studied with the most modern restoration techniques, CAT scans are done of all the objects and basically all work is done with a computer. Therefore, a modern palaeontologist is basically a computer expert. And then we use isotopes, i.e., we study the fossils at atomic level, and also at molecular level, and their DNA and other organic molecules. In other words, many discoveries are made by scientists who actually do not study morphology. So I work hard to maintain the romantic spirit of palaeontology amidst so much technology, because I don't think it should be lost.
- How many species of the Homo genre have you found in these thirty years at Atapuerca and what conclusions have you reached?
- We've discovered many things because in 1994, we still thought humans had arrived in Europe half a million years ago, and now we are working on fossils which are over one million years old. So, basically, we are studying fossils from a period of time, seven hundred thousand years of history, that no one knew anything about. In fact, we didn't even consider it history, because there had been no humans around. We knew nothing about this period and everything we are discovering and learning about is new. Therefore, we can talk about a species which is 1.2 million years old, which we are not sure about, but which could be a Homo erectus, for example. Further on, we have a species dating back some 900,000 to 800,000 years, which we named Homo antecessor, which is an evolution of Homo erectus; we also have a species from 500,000 years ago named Homo heidelbergensis. We are digging Neanderthal sites. We have not found them yet, at least that is what we think, but we may find something soon. And there is also modern humans, the Homo sapiens. So we have all of the species which have existed in the past million years or so.
- Why do you think only Homo sapiens survived?
- Basically because we substituted the others, absorbing some of their genes, but essentially replacing them. When Homo sapiens appeared in Africa there were many other species in Eurasia, maybe even in Africa, but here, in the place where we are having this conversation, lived the Neanderthals. We know of species surviving in Asia, and even the Flores Man, that curious species, existed when Homo sapiens appeared. Their expansion outside Africa substituted other humanities. We have inherited some of our genes from the Neanderthals, very few, maybe around 3%, but we are now in their place. In other words, the other humanities no longer exist because we took over.
- How do you see our future as a species, taking into account all the scientific advances and today's society? Will we disappear in the near future?
- No, that will not happen. We must deal with very serious problems, but it has always been so, it is nothing new. However, we also have huge utopias to reach. Never before have we been so close to creating a sense of brotherhood of the whole species, of all the cultures and people. Last year I read a quote from an African leader who said: “The race I belong to is Humanity”, and I would say we have never been this close to achieving that.
- Will scientific advances, such as in the field of genetics, influence our evolution?
- I wouldn't want that to happen in our evolution, but as with every tool, it can be put to good and to bad use. Now we have the ability to edit genomes, modify the genetics of any species, even of our own. Therefore, this will also happen with other species, or at least with domestic species, and the tools will also be put to some medical uses.
Like many, I believe that we will not change the species, basically because we do not have a model to follow. Those of us who have children, for example, if we had been asked how we wanted them, we would not have had an answer. Because we do not have a reference model of the human being we aspire to be. Therefore, I imagine and hope that in general people will want to continue having children in a general way, following a genetic lottery, and that is perfect, so that all our talents are well distributed. I am in favour of that, I have the feeling that our talents are well distributed and that is how it should be.
I do not think we will use technology to create a new race, but we could. We could create a completely modified human, a chimera, but I hope we never see this.
- What is the greatest discovery you would still like to make?
- Well, I do not know, I hope it will surprise me, though. Until now everything we have discovered has surprised us, because finding something you know exists is not progress. Therefore, I hope to find something I am not expecting, because that would be a novelty. However, I do hope that we all, not just me, are fortunate. I have been fortune in my life, I have been able to witness important scientific discoveries, advances, I was practically born with the discovery of the DNA. One year before my birth, Watson and Crick had discovered the molecule of biological inheritance and now we have made so much progress in this field. And in many others, the speed with which science advances makes it possible to constantly discover new things, and I hope we can see and enjoy many more of them. And that they all basically serve to make all of humanity even happier.
- What is the future of Atapuerca, in terms of management, excavation sites and the contribution of young new researchers?
- I see this project as something that will transcend generations. What we have discovered will be researched by future generations, because there is still much to study and excavations which will continue. And the new generation of researchers will discover new things. I think the project bases are set and that it lies on several pillars: one is of course research, and the network of centres conducting it, which is already a consolidated part. The other is training, which is also important, our PhD program serves to transmit our knowledge and train new researchers. And then there is dissemination, with a spectacular museum in the city of Burgos. Therefore, the three aspects which could concern us for the continuity of the project are well established and that will help the project continue its course without too many obstacles, I hope. And I would add a fourth factor: which is social participation, with the creation of a private foundation with funding from individuals and companies; this is also a guarantee for its continuity.