Genetic research has revealed how humans settled on Earth Mitochondrial DNA is only passed down through the female line, while the Y-chromosome is passed down through the male line. It is now proven all humans alive today are descended from one woman who lived in East Africa from about 124,000 to 200,000 years ago. She passed on her mitochondrial DNA to both men and women, which is why she is called the mitochondrial Eve. Obviously, she had contemporaries, but their descendants' lines were interrupted in ancient times. There was also a Y-chromosome Adam, who passed it to all modern men. He lived in Africa about 120,000 to 156,000 years ago. Thanks to this kind of research anyone today can find out where their ancestors came from.