Harsher words come from Brown, who retorts that the paper "provides absolutely no evidence that the diagnostic features in H. floresiensis are replicated in modern humans." All modern humans have chins, he insists, including microcephalics and the living Flores pygmies to whom Jacob and his co-authors refer. Neither is Brown persuaded by the analysis of LB1's facial asymmetry. "The skeleton was buried under nine meters of sediment and there was some slight distortion. I know because I put it together," he comments. "Their claims about the asymmetry being the result of abnormal growth are fiction."
Other researchers who have studied the remains are likewise critical of the new study. Susan Larson of Stony Brook University, who is analyzing the shoulder anatomy of the Liang Bua bones, disputes the authors' contention that LB1's limb bone muscle markings signify underdeveloped shoulder muscles. The authors suppose that impoverished muscles are part of the reason why LB1's upper arm bone is so straight, instead of being twisted between the elbow and shoulder like a normal modern human's humerus. But "it has been demonstrated that there is no simple relationship between size or complexity of muscle markings and the size or strength of the muscles," Larson observes. "There is no evidence that [Homo floresiensis] had weak muscles." Furthermore, she notes, most of the twisting of the humerus seen in modern humans develops in the womb, before any muscular forces can influence it. Larson's own work suggests that LB1's relatively straight humerus is a primitive characteristic, held over from a time when hominids were still transitioning from a shoulder built for quadrupedal locomotion to one possibly optimized for throwing and/or bipedal endurance running.
William Jungers, also at Stony Brook, calls the skeptics' description of the skeletal remains "a flimsy house of cards." Not only do the stature and limb proportions evident in the Liang Bua remains distinguish Homo floresiensis from all other known hominids, he says, but contrary to the claims that cross sections of the leg bones reveal pathological abnormalities, his own analyses indicate that they are normal.
For his part, Brown points out that he has since moved away from the idea that Homo floresiensis evolved its bantam body and brain proportions as a result of being isolated on a small island. More likely, he suggests, its ancestors were already small when they arrived on Flores. He notes that a paper upholding the new species interpretation, by Debbie Argue of the Australian National University and her colleagues, was recently accepted for publication in the Journal of Human Evolution.
Complicating matters is the fact that only one skull has been found at Liang Bua--LB1's. The other bones from the site fit the same small body size profile (in fact, some appear to come from individuals even smaller than LB1), but body size reveals nothing about brain size. Indeed, although modern pygmies have small bodies, their brains are comparable in size to those of large-bodied people. Paleoanthropologists mostly agree that the discovery of another small-brained hominid at Liang Bua would erase any doubts about the new species interpretation. But the Indonesian government has closed the cave to further excavation for the time being, following a bitter dispute between the discoverers and rival scientists, including Jacob. DNA retrieval and analysis, too, seems unlikely, because DNA tends to degrade rapidly under warm, wet conditions.
Morwood is thus searching for other sites in the Indonesian archipelago that could contain Homo floresiensis remains. Clues may also come from comparisons with fossils of small-bodied Homo erectus that have been recovered at a site called Dmanisi in the Republic of Georgia. Meanwhile, the skeptics will continue their quest for a specific syndrome that fits LB1's particular constellation of traits. That is to say, the Hobbit wars will doubtless continue for quite some time to come.



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