According to University of Pittsburgh anthropology professor Jeffrey Schwartz, author of the four-volume The Human Fossil Record (Wiley-Liss, 2002-05), "the discovery of any largely complete skeleton of an ancient human relative would be unique. The fact that it is a child makes it even more exciting because of what its bones and teeth might reveal that an adult's cannot."
However, Schwartz said, there are questions about the species this specimen represents. He explained that the problem is that "Lucy" and this child specimen from Dikika have been placed in Australopithecus afarensis, which is not from Ethiopia but from Laetoli, a site in Tanzania thousands of kilometers to the south. But while other specimens from Laetoli are similar to this specimen, defined as A. afarensis, a recent study of virtually all the fossils from Lucy's region of Hadar by Schwartz and Ian Tattersall, curator of anthropology at the American Museum of Natural History in New York, has revealed that none is similar in detail to the fossils from Laetoli.
"This means, of course, that no Hadar specimen is A. afarensis," said Schwartz, a fellow of the prestigious World Academy of Arts and Science.
Just as Donald Johanson, discoverer of the 3.2 million-year old Lucy, initially suggested, Schwartz and Tattersall found there is more than one kind of hominid represented in the Hadar material.
"Since the chewing surfaces of the Dikika child's teeth have not yet been exposed, one cannot compare it with any of the Hadar specimens or with the type specimen of A. afarensis from Laetoli," Schwarz explained. "Until this can be done, one cannot tell whether the Dikika child really is the first specimen of Ethiopian A. afarensis or, if not, whether it compares favorably with one of the hominids from Hadar or it represents a different taxon altogether."
Schwartz and Tattersall's The Human Fossil Record represents the first study of the entire human fossil record. Volume 1 was recognized by the Association of American Publishers with its Professional Scholarly Publishing Award.
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