Mitochondrial Eve by GlendonMellow on DeviantArt (original) (raw)
Mitochondrial Eve is a concept in biology of a bottleneck the human race passed through in its population some time in prehistory.
Mitochondria, the cell's batteries, are passed down only through the female line. They also are semi-independent symbionts with us, and mutate at a different rate.
After comparing the mitochondria of a sampling of many of the populations on Earth, scientists found everyone's mitochondria's dna is almost perfectly uniform.
It;s a beautiful, romantic idea.
You may read more at The Flying Trilobite