Definition for Mitochondrial Eve
From Biology Forums Dictionary
In the field of human genetics, the name Mitochondrial Eve refers to the matrilineal most recent common ancestor (MRCA) of all currently living anatomically modern humans, who is estimated to have lived approximately 100,000–200,000 years ago. This is the most recent woman from whom all living humans today descend, on their mother’s side, and through the mothers of those mothers, and so on, back until all lines converge on one person. Because all mitochondrial DNA (mtDNA) generally is passed from mother to offspring without recombination, all mtDNA in every living person is directly descended from hers by definition, differing only by the mutations that over generations have occurred in the germ cell mtDNA since the conception of the original "Mitochondrial Eve".