New evidence highlights failure to respect good scientific practice
When scientists found 18,000-year-old bones of a small, humanlike creature on the Indonesian island of Flores in 2003, they concluded that the bones represented a new species in the human family tree that they named Homo floresiensis. Their interpretation was widely accepted by the scientific community and heralded by the popular press around the world. Because of its very short stature, H. floresiensis was soon dubbed the "Hobbit."
Increasingly, however, this controversial conclusion is being questioned. In a Technical Comment to be published in the May 19, 2006, issue of Science magazine, scientists led by Robert D. Martin, PhD, Field Museum Provost and world-class primatologist, say that the bones in question do not represent a new species at all. A far more likely explanation is that the bones belonged to a modern human who suffered from microcephaly, a pathological condition that causes small brain size, often associated with short stature.
Keys: -- "Body size can shrink considerably, but brain size always shrinks moderately. At 400 cubic centimeters LB1's brain is simply too small to follow this universal law. In fact, for LB1 to be a dwarfed form of H. erectus, it would have to have been just one foot tall with a body weight of only four pounds to explain such a diminutive brain."
-- Based on their size, style, and workmanship, these tools [found with the remains] belong to types that are consistently associated with modern humans, or Homo sapiens, according to James Phillips, PhD, Adjunct Curator of Anthropology at The Field Museum, Professor of Anthropology at the University of Illinois at Chicago, and co-author of the Technical Comment. Such tools have never been associated with H. erectus or any other early hominid, he says. "These tools are so advanced that there is no way they were made by anyone other than Homo sapiens."
-- In research published last year that attempted to exclude this possibility, a team led by Dean Falk, PhD, studied a virtual brain cast from a single microcephalic skull – even though microcephaly can take dozens of different forms.
Furthermore, the skull from which the brain cast was made was that of a 10-year-old child, whereas LB1 was an adult and should have been compared with human microcephalics with a relatively mild condition that would have permitted survival into adulthood. Finally, the skull from which the virtual brain cast was generated is a poor-quality, plaster copy comprised of two parts that do not match up!
Not lookin' good for Homo hobbitus.
Update: John Hawks has more here and here.