Final answer:
Lucy, the famous fossil, belonged to the species Australopithecus afarensis. Discovered in Ethiopia in the mid-1970s, she provided important insights into bipedalism and human evolutionary biology.
Step-by-step explanation:
The famed bipedal hominid fossil known as "Lucy" was a member of the species Australopithecus afarensis. Discovered in the mid-1970s in Ethiopia, Lucy's fossil remains showed evidence of bipedalism and had a mixture of ape-like and human-like characteristics. This species is a significant link in the study of human evolution as it displayed both a smaller brain size akin to modern chimpanzees and a reduction in tooth and jaw size compared to earlier primates.
Lucy's discovery in 1973 by American paleoanthropologist Donald Johanson provided insight into the evolutionary transition that led from early hominins to the genus Homo, including later species like Homo erectus. With about 40 percent of her skeleton recovered, Lucy's fossil offered unprecedented evidence of how early human ancestors may have lived around 3 million years ago. Consequently, Lucy's species, Australopithecus afarensis, represented a crucial stage in human evolution, characterized by the development of bipedalism and reduction in tooth and jaw size while maintaining a small brain capacity.