This article was first published in the September 2006 ABR Electronic Newsletter.
In 2004, the world of paleontology was rocked by the news that Michael J. Morwood of the University of New England in Australia and his colleagues had discovered on the Indonesian island of Flores the remains of half-sized human ancestors that belonged to a separate species, an evolutionary offshoot of the human race, which was give the scientific name Homo floresiensis ("Flores Man"). The remains of nine individuals were uncovered, none taller than about 1 yard, and Morwood theorized that the species died out 12,000 years ago (Bower 2005: 244-5).
One of Morwood’s chief colleagues was Australian anthropologist Peter Brown, who actually made the announcement to the world. Originally he had speculated that the species died out 18,000 years ago, but, as mentioned above, Morwood moved the estimate up to 12,000 years ago. The first H. floresiensis specimen, an almost complete skeleton, was unearthed in Liang Bua cave in 2003 and given the designation LB1. The bones were shipped to the Indonesian Center for Archaeology in Jakarta, but soon after Brown's announcement Indonesian scientist Teuku Jacob took charge of LB1 and moved the remains to his own laboratory elsewhere in Indonesia (Zorich 2005: 17).
Soon thereafter, according to the science journal Discover, Flores Man "became mired in scientific controversy" (Zorich 2005: 17). Many paleontologists did not share Morwood and Brown's confidence that H. floresiensis represented an evolutionary offshoot of the human race. According to Science News: - Some scientists argue that the island population might not constitute a new branch of the human tree, but rather represent a population in which everyone had genetic defects that produced abnormally small brains and bodies...[Some researchers] now suspect that Morwood's team has mistakenly classified H. sapiens fossils as a new species (Bower 2005: 245).
A leading skeptic is anthropologist Robert D. Martin of the Field Museum in Chicago. He contends that such a small-brained creature as H. floresiensis could not have manufactured the sophisticated stone tools that have been found among the Liang Bua remains. Such tools have been found only at Stone Age H. sapiens sites. Martin has proposed that the single skull found amid the remains Morwood and Brown discovered was abnormally tiny because its fully human owner suffered from microcephaly, a genetic condition that dramatically reduces brain size and causes other developmental abnormalities (ibid.).
Another leading doubter is anthropologist Robert B. Eckhardt of Penn State University. Eckhardt examined the Flores remains and determined that Morwood and Brown's estimates of H. floresiensis' brain and body size were too low. He agreed with Martin's assessment that H. floresiensis most likely suffered from microcephaly. "I'm absolutely, totally confident that H. floresiensis will not last," Eckhardt stated (ibid.).
The most vocal representative of this position has been Teuku Jacob himself. After taking charge of LB1, he denied Brown, Morwood and others access to the fossil. He also stated, in agreement with Martin and Eckhardt, that the Flores remains represented human pygmies with microcephaly. When he measured LB1, he confirmed what Eckhardt had said: the initial estimates made by the Australian team had been too small. In fact, Jacob determined that LB1 was a foot taller, and its skull 50 cubic centimeters larger, than Brown's original assessment. Moreover, he discovered modern groups of pygmies living in isolated villages in the thick jungles near Liang Bua cave. Jacob logically concluded that the remains of Flores Man represent the direct ancestors of these small but fully modern human beings (Zorich 2005: 17).
Despite these discoveries, Brown remains firm in his belief that Flores Man evolved from an isolated group of Homo erectus that developed smaller bodies to cope with the island’s limited resources (Zorich 2005: 17). The controversy continues.
Recommended Resources for Further Study
References:
Bower, B. 2005. "“Encore for Evolutionary Small-Timers." Science News 168, no. 16.
Zorich, Z. 2005. "The Latest Flap over Flores Man." Discover 26, no. 3.