Fifty years ago, the discovery of the Lucy fossil

This November 24, 1974, in the desert region of Hadar, in the northeast of Ethiopia, an international team of paleoanthropologists is working on the fossil sites. Among them, Donald Johanson and Tom Gray, one of his students. After a long morning under the blazing sun, the two men decide to change their usual route to return to their vehicle. Destiny, it seems, chooses this moment to reveal its secrets. Among the rocks and sand, Johanson's keen eye is drawn to something unusual…

A fragment of bone – a right proximal numerus ulna – then a skull, a femur, a few ribs, part of the pelvis. After weeks of diligent work, the team was able to identify and catalog nearly 42 bones belonging to a single individual, an Australopithecus. This skeleton, affectionately named Lucy by the team who listened to the Beatles song, is remarkably complete for its age. The discovery of Lucy, fifty years ago, marks a new era in our understanding of the origins of humanity. This fossil, 3.2 million years old, has become one of the centerpieces of the great story of human evolution, popularized by paleoanthropologist Yves Coppens.

“Such a complete skeleton is extraordinary!”

The geologist and palynologist (pollen specialist) Raymonde Bonnefille, honorary research director at the CNRS, is one of the rare women to have participated in explorations in the region where Lucy was discovered, on the initiative of her colleague Maurice Taieb. “I was aware that we were bringing something new and important to the knowledge of the ancient evolution of hominids, but I did not think that I would be talking to you about it fifty years later!”

“It's extraordinary to have such a complete and ancient skeleton, explains paleoanthropologist Sandrine Pratt. Even if at the time, in 1974, there was no precise dating, we knew that we were over 3 million years old.“Although Lucy's skeleton is not complete, the 52 fragments discovered, corresponding to 42 bones, made it possible to represent approximately 40% of the skeleton. “We were able to estimate her stature, between 1.05 and 1.10m, roughly the equivalent of a 6-year-old child currently. In terms of weight, she is between 25 and 30 kilos, so she is a little female.”

Yves Coppens: “Not yet a man, just before man”

Thanks to a wisdom tooth, and knowing that ancient hominids grew a little earlier, scientists deduce that Lucy was 12 or 13 years old. Analysis of its pelvis and elements of the femur also indicate that it is bipedal, and that it is also capable of climbing.

But it was not until 1978 that this new species of Australopithecus was named Australopithecus afarensisof which Yves Coppens will say: “Lucy represents the hominid, the member of the human family who is not yet a man, just before man”. As for the reasons for Lucy's death and extinction, several hypotheses are still discussed and the question remains open…

Guests

• Raymonde Bonnefille, normalienne, biologist, trained geologist and palynologist (specialist in the study of pollen). Author of In Lucy's footsteps (Odile Jacob), she participated in the expeditions preceding the discovery of Lucy. Having worked with French and American teams, she will link Yves Coppens, Donald Johanson, Maurice Taieb and Jon Kalb, who will create the International Afar Research Expedition (IAER) in 1972. C onference on Saturday, November 16 at the Musée de l'Homme at 12 p.m., on the occasion of the special weekend.
• Sandrine Pratpaleoanthropologist, CNRS research director at the Natural History of Prehistoric Man laboratory. Conference on Saturday, November 16 at 4:30 p.m.: Lucy and her family. What did Lucy and her loved ones look like? What was their diet like? When and where did they live?