Did our species do them in?
The new analysis dramatically pushes back the time of disappearance of the Hobbits and associated unique animals from the site.
Before now, it was thought that these little archaic humans (Homo floresiensis) died out around 12,000 years ago, but new excavations at Liang Bua cave show that the Hobbits, as well as many other animals, disappeared 38,000 years earlier -- at about the exact same time our species first arrived in the wider region.
The timing, say scientists, is suspicious.
Bert Roberts of the University of Wollongong and co-author of the study, which appeared in Nature, told Discovery News: "The earliest known evidence of modern humans on Flores is from about 11,000 years ago and after, but we do know that modern humans were on other islands in the region around this time and had reached Australia by 50,000 years ago. So it is certainly a possibility to be considered, but solid evidence is needed in order to demonstrate it."
Climate shifts and volcanoes might have also led to the sudden demise of species in and around Liang Bua, co-lead author Matt Tocheri of Lakehead University and the Smithsonian Institution's Human Origins Program added.
Another possibility is that the tiny elephant relative, pygmy Stegodon, might have been hunted to death, leading to a devastating chain reaction.
"Pygmy Stegodon is the only large-bodied herbivore known on Flores during the Late Pleistocene, and it was clearly a primary food source for these other species," Tocheri explained. "If something happened to cause the pygmy Stegodon to crash, then it more than likely would have had an adverse effect on these other species."
The confusion about when the Hobbits and associated animals died out at Flores had to do with the depth and complexity of the cave site's geological layers.
The scientists discovered that an eroded surface sloped steeply toward the cave entrance. Much younger sediments covered it during the past 20,000 years. These newer sediments were at first attributed to the Hobbit remains, but the recent and more extensive analysis disproved that idea.
The latest excavation, instead, found that the Hobbits' skeletal remains date from 100,000 to 60,000 years ago, but stone tools consisting of hammered flakes and cores that were made by the Hobbits continue until about 50,000 years ago.
The earliest evidence of humans on Flores comes from an area called the Soa Basin, lead author Thomas Sutikna of the University of Wollongong and the National Research Center for Archaeology said. One million-year-old stone tools were found at Soa Basin and could have been made by the Hobbits or their ancestors.
The Hobbit's origins are murky, but it is suspected that they either evolved from Homo erectus, or descended from another, unknown, species of human that might have left Africa 1 to 2 million years ago.
Their skeletons, first reported in 2004, reveal that they had extremely small, chimpanzee-sized brains and that adults only stood about 3.5 feet tall. They resembled fossil human species that lived in Africa and Asia 1 to 3 million years ago.
Donald Johanson, founding director of the Institute of Human Origins at Arizona State University, said, "The exact cause of the demise of the hominids and associated animals is not yet understood, but in my view, may be related to the appearance in the area of the most aggressive of all hominin species, Homo sapiens, modern humans."
Bernard Wood of George Washington University's Center for the Advanced Study of Human Paleobiology said, "What we need now are other sites that preserve Homo floresiensis to see if their demise, and the demise of the animals and birds found with them at Liang Bua, can be linked in any way with the arrival of modern humans. Watch this space!"
Read more at Discovery News
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