African mothers

In 1987, US scientists looked at variations in mitochondrial DNA to trace the origins of the first modern human females. Mitochondrial DNA is passed on by mothers (but not fathers) to their children, and so can be used to trace the female line. Their results supported the 'Out-of-Africa' theory: the mitochondrial DNA of every population in the world today can be traced back to early African mitochondrial DNA. Scientists suggest our most recent common female ancestor lived in Africa about 200,000 years ago.