Lucy (Australopithecus)

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Catalog number:	AL 288-1
Common name:	Lucy
Species:	Australopithecus afarensis
Age:	3.2 mya
Place discovered:	Afar Depression, Ethiopia
Date discovered:	1974
Discovered by:	Donald Johanson

Lucy (Amharic ድንቅነሽ dinqneš, "you are wonderful") is the common name of AL 288-1, the first Australopithecus afarensis skeleton ever discovered. It was discovered on November 30, 1974 by Donald Johanson, Maurice Taieb, Yves Coppens and Tim White in the Middle Awash of Ethiopia's Afar Depression. Lucy is estimated to have lived 3.2 million years ago.

1 Discovery
2 Notable Characteristics
3 See also
4 External links

[edit] Discovery

A team headed by Donald Johanson, an American anthropologist now head of the Institute of Human Origins of Arizona State University, was invited to join an international expedition organized by French geologist Maurice Taieb. The team surveyed Hadar, Ethiopia during the late 1970s for artifacts related to the origin of humans. On November 30, 1974 near the Awash River, Johanson abandoned a plan to update his field notes to join one of his students, Tom Gray, searching for bone fossils. Both were on the hot arid plains surveying the dusty terrain when a fossil caught Johanson's eye; arm bone fragments on a slope. As they looked further, more and more bones were found, including a jaw, arm bone, thighbone, ribs, and vertebrae. Both Johanson and Gray carefully analyzed the partial skeleton and calculated that an amazing 40% of a hominin skeleton was recovered, which, while sounding generally unimpressive, is astounding in the world of anthropology. Usually, only fossil fragments are discovered; rarely are skulls or ribs found intact. As the team analyzed the fossil further, Johanson argued it was female based on the feminine stature of the skeleton. The skeleton AL 288-1 was nicknamed Lucy, after the Beatles song "Lucy in the Sky with Diamonds", which Johanson was listening to when he discovered the first bone. Lucy was only 1.1 m (3 feet 8 inches) tall, weighed 29 kilograms (65 lb) and looked somewhat like a Common Chimpanzee, but the observations of her pelvis proved that she had walked upright and more in the manner of humans.

Johanson placed Australopithecus afarensis as the last ancestor common to humans and chimpanzees living from 3.9 to 3 million years ago. Although fossils closer to the chimpanzee line have been recovered since the early 1970s, Lucy remains a treasure among anthropologists studying Human origins. The fragmentary nature of the older fossils furthermore deter confident conclusions as to the degree of bipedality or their relation to true hominines.

Johanson brought the skeleton back to Cleveland, under agreement with the government of the time in Ethiopia, and returned it according to agreement some 9 years later. Lucy was the first fossil hominin to really capture public notice, becoming almost a household name at the time. Current opinion is that the Lucy skeleton should be classified in the species Australopithecus afarensis. Lucy is preserved at the national Museum in Addis Ababa, Ethiopia. A plaster replica is displayed instead of the original skeleton. A diorama of Australopithecus afarensis and other human predecessors showing each species in its habitat and demonstrating the behaviors and capabilities that scientists believe it had is in the Hall of Human Biology and Evolution at the American Museum of Natural History in New York City.

Further discoveries of afarensis specimens occurred during the 1970's giving anthropologists a much better appreciation of the range of variability and sexual dimorphism of the species.

[edit] Notable Characteristics

One of the most striking characteristics possessed by Lucy was that she had a bipedal knee structure, and molars and front teeth of human (rather than great ape) style and relative size, but a small skull and a small body. The image of a bipedal hominid with small skull, but teeth like a human, was quite a revelation to the paleoanthropological world at the time.

This was due to the earlier belief (1950-1970's) that increasing brain size of apes was the trigger for evolving towards humans. Before Lucy, a fossil called '1470' (Homo rudolfensis) with a brain capacity of about 800 cubic centimetres had been discovered, an ape with a bigger brain. If the older theory was correct, humans most likely evolved from the latter. However, it turned out Lucy was the older fossil, yet Lucy was bipedal (walked upright) and had a brain of only around 375 to 500 cc. These facts provided a basis to challenge the older views.