Since her public debut in 1978, Lucy has been on a first-name basis with the world. Not bad for someone from rural Ethiopia who had been an unknown for 3.2 million years or so.
Paleoanthropologists Donald Johanson and Tom Gray had discovered Lucy’s fossilized bones a few years earlier (SN: 1/4/75, p. 4). That spectacular moment 50 years ago quickly upended how many scientists thought about human evolution. Until then, the history of our species was drawn as an orderly progression, with one member of the big-brained Homo species leading to the next. The famed anthropologists Louis and Mary Leakey, and later their son Richard, had spent decades excavating fossils that they said supported that theory.