The Neandertal, the enigmatic Stone Age man who appears to have vanished without a trace from the earth 30,000 years ago, lives on in modern humans. Each of us carries up to four percent of Neandertal genes. Researchers working with Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig worked on decoding the Neandertal genome for 20 years and compared it with the Homo sapiens genome. In the process, the researchers explored a series of questions: What does the Neandertal genome divulge about us modern humans, and how do we differ from each other? Which human capacities and characteristics hark back to Stone Age man? Why did our closest relative become extinct? One thing is now certain: the Neandertal and modern man mixed - and we are far more closely related than we previously believed.