For Immediate Release Contact: Greg Borzo (312) 665-7100 gborzo@fieldmuseum.org Scientists scuttle claims that "Hobbit" fossil from Flores, Indonesia, is a new hominid New evidence highlights failure to respect good scientific practice CHICAGO—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. The proposed new hominid species is based primarily on a specimen known as LB1 consisting of a diminutive adult skull and partial skeleton about three feet tall. Initially, H. floresiensis was claimed to be a dwarf derived from Homo erectus (“upright man”), a human ancestor that lived as far back as 1.8 million years ago. This seemed like an appealing explanation because islands are known to play tricks on the evolution of animals, sometimes causing them to shrink due to limited food supplies and the reduced presence of predators. But all mammals that have shrunk due to the constraints of an island’s resources – or any other reasons, such as selective breeding – have done so within certain parameters: 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. “The tiny cranial capacity of LB1, which is smaller than in any other known hominid younger than 3.0 million years old, is demonstrably far too small to have been derived from Homo erectus by normal dwarfing,” Dr. Martin says. Series of problems Small brain size is just one of several problems with the science behind claims that LB1 represents a new species, according to Dr. Martin and his colleagues. The primary problem, clashing directly with the tiny brain size, is the sophisticated nature of the stone tools found in the same cave deposits where the fossils were discovered. Based on their size, style, and workmanship, these tools 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.” Continue>>