Google has celebrated the 41st anniversary of Lucy's discovery - November 24 - with a Google Doodle showing the evolution of bipedalism with a simplified version of the March of Progress, the common illustration of human evolution.
She belonged to a species that shared both human and ape characteristics
Tuesday’s Google Doodle marks the discovery of “Lucy”, a skeleton found 41 years ago in Ethiopia that helped scientists understand the evolution of apes into bipedal humans.
In 1974, archaeologists Donald Johanson and Tom Gray found 47 bones, around 40 per cent of the skeleton's likely total, giving them enough information about the species to help understand the transition to homo sapiens.
Based on the skeleton's pelvic structure, they deduced that it was female, and gave it the name "Lucy", after Lucy in the Sky With Diamonds, the Beatles song that was playing back at their camp.
Although Lucy had many of the characteristics of chimpanzees, such as long arms and a protruding belly, the skeleton showed that she primarily walked upright, the earliest example of such a primate. Bipedalism is seen as one of the key distinctions between the Homo genus and Pan, the family of chimpanzee species.
Before her discovery, scientists had speculated that bipedalism came alongside the development of larger brains, but Lucy's was barely larger than those of chimpanzees.
Named after the Beatles song “Lucy in the Sky With Diamonds,” the 3.2 million-year-old remains belong to the Australopithecus afarensis family, a species that shares both human and ape characteristics, according to the Telegraph.
Almost 40% of Lucy’s skeleton remained intact — a particularly rare occurrence given most fossils of that age are found shattered and fragmented — allowing researchers to study the distinct curvature of her spine and her knees and uncover her ability to walk upright, the Independent reports.
The Doodle shows an Australopithecus afarensis walking between a chimpanzee and a human, marking the transition between the two species.
Lucy's species, known as Australopithecus afarensis, is believed to have lived between 3 million and 4 million years ago, and is the closest primate to the Homo genus.
Homo Habilis, the earliest form of Homo, is believed to have descended from Afarensis or subsequent species of Australopithecus before homo sapiens came on the scene about 200,000 years ago.
Google's Doodle shows a walking Australopithecus afarensis is placed in between an ape and modern human, showing how Lucy's discovery filled the gap between the two.
Nowadays, Lucy's bones are kept in a museum in Ethiopia, although they spent six years touring the US from 2008 to 2013. Barack Obama visited the fossil on a trip to Africa earlier this year, and was permitted to touch it, something usually reserved for scientists.
Lucy's skeleton suggests she was around 3 feet 3 inches tall, and weighed around 60 pounds. Five years ago, a discovery suggested that her species used crude stone tools to cut and eat meat, putting estimates of our ancestors' first use of technology back almost a million years.