Donald Johanson: Unearthing Lucy changed my life and the world

When palaeoanthropologist Donald Johanson discovered a bone fragment at the Hadar fossil site in Ethiopia in 1974, he knew it was an extraordinary find, but little did he know just how much it would alter our understanding of human evolution. More fossils were unearthed; a complete lower jaw, parts of a ribcage, pelvis and shin bones, ultimately resulting in a 40 per cent complete skeleton.

Johanson’s find became known as Lucy – named after the Beatles song Lucy in the Sky With Diamonds – a 3.2 million-year-old female skeleton that gave an unprecedented picture of her species, Australopithecus afarensis. “We knew that because it was so complete it was important, but I didn’t realise it would actually launch a new species,” says Johanson.

Lucy’s anatomy provided evidence that this relatively small-brained species was bipedal, walking upright, suggesting that not only was she a human ancestor, but that our bipedalism preceded brain expansion. 50 years on, Johanson remains humbled, reflecting on Lucy’s continual impact on the world of science, his life and career. “If I’d looked to my left, I would’ve missed her and my life would’ve been incredibly different,” he says.

Read more: What is a human? Why the split from our ancestors is so hard to define