GENETICS

Mitochondrial Eve

~200,000 years ago

Palaeolithic · Middle Stone Age · MIS 7

In 1987, mitochondrial DNA from 147 people across five regions of the world was stitched into a single family tree, and its root lay in Africa, in a woman who lived roughly 200,000 years ago. The press named her mitochondrial Eve. A larger study of 189 people, including 121 Africans, confirmed the shape of the tree, its deepest branches all African, and placed the common maternal ancestor between about 166,000 and 249,000 years ago.

Why it matters

Eve is the most misread figure in genetics. She was not the first woman, and not alone: her contemporaries have living descendants too, just not through an unbroken chain of daughters. Every gene traces its own tree to its own ancestor, most of them far older than her. What the mitochondrial root really showed is that the deepest branches of humankind grow inside Africa, and that everything outside is a recent shoot.

Dating & uncertainty

This is a statistical date, not a fossil. Coalescence estimates depend on the assumed mutation rate and its calibration: proposals have ranged from about 100,000 to 250,000 years, and the 1991 study, calibrated against chimpanzees, gave 166,000 to 249,000 years. The name is kept here because it is universal, not because one woman mothered us all: population genetics says otherwise.

Sources

1. Cann, Stoneking & Wilson (1987), Nature · Mitochondrial DNA and human evolutiondoi:10.1038/325031a0
2. Vigilant et al. (1991), Science · African populations and the evolution of human mitochondrial DNAdoi:10.1126/science.1840702
3. Ayala (1995), Science · The myth of Eve: molecular biology and human originsdoi:10.1126/science.270.5244.1930

Our species’ history as one day

08:45:4215 h 14 min before midnight

if the 315,000 years of Homo sapiens were compressed into a single day