Man’s Place in Nature Evidence as for the early stages of human evolution

Upon the discovery of Australopithecus afarensis remains in the 1970s and the subsequent acknowledgment of the remains’ distinct taxonomic status, the new species was hailed as situated anatomically and chronologically “halfway” between an ape (the common ancestor of the chimpanzee and Homo sapiens) and modern humans. Furthermore, the primitive appearance displayed by A. afarensis, along with its age, rendered it an ideal link in the chain leading to modern human. 
Beginning in the 1990s, the intensive activity of numerous expeditions to the Hadar region of Ethiopia (site of the earlier A. afarensis finds, including the famous Lucy) and the discovery of two complete skulls, filled many gaps in our understanding of A. afarensis cranial anatomy and role of this species in human evolution.