DNA-SCIENCE: An international team, lead by researchers from the universities of Copenhagen and Aarhus, has shed light on a mysterious 5000-year-old mass grave in Poland. Despite being killed brutally, the victims were buried carefully, flanked by gifts, in a mass grave. Ancient DNA has revealed the mass murder to be that of a large family. The new research results shed light on a particularly violent era in European prehistory of which little is known. The study has just been published in the prestigious American journal, Proceedings of the National Academy of Sciences (PNAS).