When Lucy the Australopithecus was unearthed in Ethiopia in 1974, she seemed to fill a gap in the human family tree. The 3.2-million-year-old hominid had both ape and human characteristics.
Lucy, of the species Australopithecus afarensis, likely walked upright like a human but had an apelike head and other features similar to chimpanzees – humans’ closest living relatives – placing her on the human lineage after the evolutionary split from other great apes.
Google honored the 41st anniversary of the discovery of this iconic specimen with a Google Doodle on Tuesday, Nov. 24, 2015.
Paleoanthropologist Donald Johanson and his graduate student Tom Gray found part of Lucy’s arm bone in ravines near Hadar in northern Ethiopia. After realizing the significance of their find, the scientists searched for more pieces of the mysterious ancient hominid female.
Ultimately a team of scientists found 47 bones, comprising nearly 40 percent of her skeleton.
Walking upright into human evolution
Lucy immediately stood out to scientists because of the structure of her knee and pelvis. These bones showed that, like humans today, this ancient hominid walked on two legs, body upright.
The tendency to walk upright on two legs, bipedalism, is a key distinction between humans and other apes. Because of her mix of traits, Lucy sits on the evolutionary line between those apes and humans.
But at three-and-a-half feet tall, Lucy wasn’t quite human. She had the long, dangly arms, short legs, and a torso much like chimpanzees and other apes. Lucy likely had a small brain and an otherwise apelike head too.
Speaking to Time Magazine in 2009, Dr. Johanson explained that it’s Lucy’s evolutionary position that makes the specimen such an important find.
“Lucy is really at a nice point on the family tree: she sits at this pivotal point between things that are more ancient and things that are more modern,” he said.
“She showed us conclusively that upright walking and bipedalism preceded all of the other changes we'd normally consider being human, such as tool-making. She gave us a glimpse of what older ancestors would look like.”
Becoming human with a name
Ancient specimens don’t always get a name like Lucy. Scientists have unearthed A. afarensis remains in half a dozen locations in Ethiopia and Kenya. But giving Lucy a name may have made her more accessible.
Lucy was named after the Beatles’ song “Lucy in the Sky with Diamonds.” A huge Beatles fan, Johanson had the whole camp of scientists listening to the band during their archaeological expedition.
When “Lucy in the Sky with Diamonds” played, inspiration sparked. “Initially I was opposed to giving her a cute little name, but that name stuck,” Johanson told Time.
It didn't just stick, it became a household name. Johanson added, “I must say, her name is one that people find easy and non-threatening. People think of her as a real personality.”