In 2003, archaeologists excavating in a cave on the Indonesian island of Flores made a discovery that forced scientists to completely rethink conventional theories of human evolution. They reported the discovery of a new species of human, one that lived as recently as 12,000 years ago, at the same time as modern humans. But others disagreed, arguing the one-metre-high skeleton was a modern human that suffered from a deformity known as microcephaly.
     The debate has raged ever since. But Debbie Argue, a PhD student from the Australian National University's Department of Archaeology and Anthropology, believes she has settled the question by comparing bone fragments from the hobbits to other hominids. "We discovered that Homo floresiensis ranged off the family tree almost at the beginning of the evolution of our genus, Homo. So that would have been over two million years ago, and as such a very, very primitive being." The team used 'cladistic' analysis - the first time this has been used in relation to Homo floresiensis. Ms Argue and her colleagues compared up to 60 characteristics from a range of early hominins, including H. erectus, and modern humans. They used two different computer-based modelling systems, testing relationships between the species to find the most parsimonious, or simplest, evolutionary line. The results have been published in the Journal of Human Evolution.
     Ms Argue describes the work as a paradigm shift in archaeology, overturning the notion that Homo sapiens were the only hominids on the planet after the extinction of Homo erectus and the Neanderthals. "We know that Homo floresiensis was, in Flores at least, from 100,000 years ago to about 12,000 years ago. And at that time, or at least from 40,000 years ago, we had modern humans in Asia and New Guinea and Australia. So here we were sharing the planet where we thought we'd been the only people that survived after the end of the Neanderthals."

Sources: ABC.net.au (2 August 2009), Science Alert (5 August 2009)