My first book tells the story of research into the human origins using DNA. I had become interested in this field after Dr. Robert Hedges, the director of the Oxford Radiocarbon Laboratory and I managed to extract DNA from some of the ancient bones stored in his department. It was soon clear that in order to put our results into context we needed to know much more about modern populations so we began collecting thousands of DNA samples from all over the world. We concentrated on mitochondrial DNA because that was the DNA we had extracted from the ancient bones. We soon began to appreciate its special qualities. Firstly there was plenty of sequence variation to work with and secondly the simplicity of its strictly matrilineal inheritance pattern avoided the complexity of genetic recombination which scrambles DNA at every generation. We discovered that mitochondrial DNA fell into a small number of distinct clusters which, by an inevitable logic, must have originated from a single woman at some point in the distant past. The Pleaides, the mythological parallel to Eve In Europe there are just seven clusters descended from seven women covering over 97% of Europeans. In the book I wanted to emphasise that these ancient women were real individuals rather than statistical constructs and deserved their own names - Ursula, Xenia, Helena, Velda, Tara, Katrine, Jasmine. I worked out how long ago, and whereabouts, they lived. From this and archaeological evidence I imagined what their lives had been like. When the book was published in 2001 the lab was flooded with requests from people wanting to know which of these women was their own ancestor. To cope with this completely unexpected demand the University set up Oxford Ancestors, the world's first genetic genealogy company, which continues to this day.