Since this is a blog about the origin of humans and their history through time I thought a good place to start would be as far back as possible, which leads me to Bryan Sykes of Wolfson College, Oxford and this great book he wrote on genetics. The Seven Daughters of Eve explains how all Europeans came from one of seven women based on genetic studies done on mtDNA. This number is contested and some believe there are as many as eighteen haplogroups, with even more additions if you include all people outside of Africa. Although the women didn’t all live at the same time, they do all trace back to one woman, the mitochondrial Eve. Sykes is now studying the nine Japanese haplogroups, none of which coincide with the European groups.
Although many people may have left Africa to travel north, not many of them survived. The time and place for a successful exit was limited. It is amazing to think that only a handful of women survived all the attempts to travel north to find a better, more abundant life.
You can find more information about Bryan Sykes and his other books here Wolfson