I have spent the last three days on Gotland, touring the famous fossil sites with my colleagues and 44 students. Most of the students were beginners and had just started their geology course last week. Others had already taken geoscience courses and were more familiar with the subject. Geology is very much a field science and without seeing rocks, sediments, and fossils in their context, it is difficult to imagine and understand what all this is about. Although I am sure that the students learned a lot, discovered fossils, took samples home, and now know that the Silurian rocks on Gotland are 430 million years old, they probably are also quite confused by the new terminology and by the fact that geological time is gigantic.
Tomorrow my next excursion starts, now to France and back to Les Eyzies with the students who took our evening class in Human Evolution earlier this year. Students from Lund and Stockholm University will – during four days – visit the famous archaeological sites dating from the time of the Neandertals and the Cro Magnons (anatomically modern people). I am sure we will discuss the recent news that all of us have 2.5% Neandertal genes, and that North Europeans can thank the Neandertals for parts of their immune system.
The question whether Neandertals and modern humans had had contacts and were interbreeding with each other had been longstanding, until the publication of new genetic research in May 2010 that showed that modern humans mingled with both Neandertals and a group, called the Denisovans, who lived at about the same time. While Europeans and Asians carry about 2.5% Neandertal DNA, living Melanesians also have 5% Denisovan DNA. This discovery was partly possible because of the find of a little girl’s finger bone in a cave in Siberia, which showed that it belonged to the hitherto unknown Denisovans, and partly it was based on sequencing of DNA from Neandertal finds.
DNA analyses can tell us very much about our ancestors, and has revolutionised the way we now view the most recent part of human evolution. However carefully made archaeological excavations, demonstrating that finds of Neandertals, Denisovans and anatomically modern humans can be made in the same layer and date to the same time period, are really needed. So much is still based on speculation!
A new temporary exhibition at the Musée de la Préhistoire in Les Eyzies entitled A Thousand and One Women of the End of the Ice Ages will show a variety of Magdalenian tools and art made of ivory, antler, and flint from many major archaeological sites in Poland, Germany and France. I am really looking forward to see this exhibition, especially since one of my very old friends and a specialist in Magdalenian culture will join in.