Hobbits Of The South Pacific

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From the start, says Morwood, "it was pretty obvious that this was not a modern human. It had a big brow and a massive nutcracker jaw," some of the telltale characteristics of H. erectus. But, he says, "it's very unlike the Homo erectus you get in Java." In fact, he believes the Hobbit most closely resembles specimens found in the Republic of Georgia that date back 1.7 million years. "It's obvious," Morwood says, "that human evolution has been much more complex than we'd realized."

It's even more obvious when you consider the Hobbit's diminutive size. The creature clearly wasn't an ape. It resembled the famous Lucy in stature and brain size, but the shape of the skull is very different; besides, Lucy is more than 3 million years older. The tiny brain also rules out the theory that this was a type of Pygmy, midget or dwarf, whose brains are all comparable in scale to those of full-size adults. But evolution does provide an explanation, known to biologists as the Island Rule: when isolated on small islands in the absence of big predators, large mammals tend to evolve toward smaller sizes. That's because they don't need to fight off attackers and because smaller individuals can get by better on limited resources. (Paradoxically, small animals on islands tend to grow larger, and Flores was populated with giant rats and lizards, including Komodo dragons.)

The Island Rule is almost certainly the reason Stegodon dwindled to the size of a water buffalo on Flores. But while examples of such shrinkage had been found in elephants, hippos and deer, it was unheard of in higher primates. "It shows that hominids are following the same evolutionary and ecological rules as other mammals," says paleontologist Tim White of the University of California, Berkeley. "Wallace and Darwin would have been delighted."

Despite their minuscule brains, the Hobbit and her kin were evidently smart enough to use fire, make tools and hunt, challenging existing notions of the relationship of brain size to intelligence. The scientists found bones of Stegodon, Komodo dragons and an assortment of rodents and other animals in the Liang Bua sediments, some of them charred by what may have been cooking fires.

The scientists also unearthed stone tools, including sophisticated points, blades, awls and tiny barbs that were probably attached to sticks to make spears. Although the evidence is circumstantial, Morwood and his team are convinced that the tools were made by H. floresiensis. Even though modern humans were living in the region at the same time, their bones don't appear in the layers with the tools. If the two species were contemporaries, of course, there is also the disturbing possibility that we killed and ate our smaller cousins — although there is no evidence to support that horrifying idea.

Besides some basic evolutionary questions, the presence of the Hobbit on Flores raises a practical one as well: How did her ancestors get there in the first place? Unlike elephants, which are surprisingly buoyant, they couldn't have swum the roughly 12 miles that separated Flores from the nearest land even when sea level was at its lowest. Rats and other small mammals could have floated over on flotsam, but if the first human settlers had hitched a ride on tree trunks or large mats of vegetation, you would expect other large mammals — pigs, deer, monkeys, tigers — to have done so as well.