29 October 2004
A tiny species joins human family tree
Scientists have discovered a new and tiny species of human that lived in Indonesia on Flores island until at least 12,000 years ago. Details of the sensational find are described in the journal Nature. The finding on the remote island has stunned anthropologists like no other in recent memory. It is a fundamentally new creature that bears more of a resemblance to fictional, barefooted hobbits than modern humans. Yet biologically speaking, it may have been closely related to us and perhaps even shared its caves with our ancestors.
Australian archaeologists unearthed the bones while digging at a site called Liang Bua, one of numerous limestone caves on Flores. The remains of the partial skeleton were found at a depth of 5.9m. At first, the researchers thought it was the body of a child. But further investigation revealed otherwise. Wear on the teeth and growth lines on the skull confirm it was an adult, features of the pelvis identify it as female and a leg bone confirms that it walked upright like we do.
"When we got the dates back from the skeleton and we found out how young it was, one anthropologist working with us said it must be wrong because it had so many archaic [primitive] traits," said co-discoverer Mike Morwood, associate professor of archaeology at the University of New England, Australia. The 18,000-year-old specimen, known as Liang Bua 1 or LB1, has been assigned to a new species called Homo floresiensis. It was about one metre tall with long arms and a skull the size of a large grapefruit.
The researchers have since found remains belonging to six other individuals from the same species. The specimens' ages range from 95,000 to 12,000 years, meaning they lived until the threshold of recorded human history and perhaps crossed paths with the ancestors of today's islanders. Chris Stringer, head of human origins at London's Natural History Museum said the long arms were an intriguing feature and might even suggest H. floresiensis spent much of its time in the trees. Studies of its hands and feet, which have not yet been described, may shed light on this question. As modern human beings were present in the region at least 45,000 years ago, and are known to have reached Flores, it is certain that the two species encountered one another.
H. floresiensis probably evolved from another species called Homo erectus, whose remains have been discovered on the Indonesian island of Java. Homo erectus may have arrived on Flores about one million years ago, evolving its tiny physique in the isolation provided by the island. What is surprising about this is that this species must have made it to Flores by boat. Yet building craft for travel on open water is traditionally thought to have been beyond the intellectual abilities of Homo erectus.
Even more intriguing is the fact that Flores' inhabitants have incredibly detailed legends about the existence of little people on the island they call Ebu Gogo. The islanders describe Ebu Gogo as being about one metre tall, hairy and prone to "murmuring" to each other in some form of language. They were also able to repeat what islanders said to them in a parrot-like fashion. "There have always been myths about small people - Ireland has its Leprechauns and Australia has the Yowies. I suppose there's some feeling that this is an oral history going back to the survival of these small people into recent times," said co-discoverer Peter Brown, an associate professor of archaeology at New England.
The last evidence of this human at Liang Bua dates to just before 12,000 years ago, when a volcanic eruption snuffed out much of Flores' unique wildlife. Yet there are hints H. floresiensis could have lived on much later than this. The myths say Ebu Gogo were alive when Dutch explorers arrived a few hundred years ago and the very last legend featuring the mythical creatures dates to 100 years ago. But Henry Gee, senior editor at Nature magazine, goes further. He speculates that species like H.floresiensis might still exist, somewhere in the unexplored tropical forest of Indonesia. Professor Stringer said the find "rewrites our knowledge of human evolution." He added: "To have [this species] present 12,000 years ago is frankly astonishing."
Homo floresiensis might have evolved its small size in response to the scarcity of resources on the island. "When creatures get marooned on islands they evolve in new and unpredictable courses. Some species grow very big and some species grow very small," Dr Gee explained. The sophistication of stone tools found has surprised some scientists given the human's small brain size of 380cc (around the same size as a chimpanzee). "The whole idea that you need a particular brain size to do anything intelligent is completely blown away by this find," Dr Gee commented. Because the remains are relatively recent and not fossilised, scientists are even hopeful they might yield DNA, which could provide an entirely new perspective on the evolution of the human lineage. Researchers think that its intelligence was similar to Homo erectus, and “toy-size” tools discovered in the cave suggest that it used these to hunt. It is clearly a separate species from Homo sapiens, and not just a smaller version like modern pygmies: these have brains of similar size to other human beings.
For now, most researchers have been limited to examining digital photographs of the specimens. The female partial skeleton and other fragments are still stored in a laboratory in the Indonesian capital Jakarta.
Sources: Associated Press, BBC News, The Times, Yahoo! News (27 October 2004), Reuters (28 October 2004)