["Researchers of human origins believe that the ancestry of humans can be traced by analyzing mutations of the DNA contained in the mitochondria of every cell...
The mitochondrial Eve idea is only valid if humans receive mtDNA only from the mother and if the rate of mutation is constant and known. Since none of these assumptions are known, the dating method may be invalid. Since recent research indicates tha there is mixing of paternal and maternal mtDNA, no conclustion about the rate or origin is reliable--mitochondrial Eve appears to be dead..."
]
Exposing Evolution. Second Ed.