There was quite a stir in anthropological circles when, in 1974, a new species was found in the Afar region of Ethiopia. The specimen was nicknamed Lucy and was dated at approximately 3.2 million years ago and, until now, was believed to be a unique specimen of an ancestor of our own Homo Sapiens species. Now scientists and research teams working in Kenya and Chad have found similar, but not identical fossilised skeletal remains.
     Theses fossilised bones have been dated to the same period as Lucy, between 3.7 and 3.0 million years ago. The question which now needs to be asked is, are these remains similar to Lucy and therefore contenders as her close relatives or are they so distinctly different that they could be classed as a new species? The differences found so far are quite subtle, in terms of size of teeth, shape of cheekbones and thickness of jaw.
     Johannes Haile-Selassie, the team leader & paleoanthropologist at the Cleveland Museum of Natural History, Ohio (USA) puts the differences down to diet and states that the new find "was probably adapted to harder, tougher and more abrasive dietary sources."
     The battle between the two schools of thought rages on with, in one corner, Carol Ward of the University of Missouri, Columbia (USA) claiming that the fossils "do fall outside of the range of variation of any species found so far", although she caveats that claim by stating that more examples would be needed for a true comparison.
     In the other corner is William Kimbel, a paleoanthropologist from Arizona State University (USA) who states that "the distinctions in my view are pretty subtle". A statement echoed by Tim White of the University of California (USA) who said "the slight anatomical differences noted in the case fall short of demonstrating biological species diversity".
     The debate will continue until more evidence is found to prove one or the other of the theories the most convincing.

Edited from Science Magazine, Reuters (27 May 2015)