Bones of Contention

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he virulence of the invective isn't surprising given what's at stake. If proved correct, the existence of H. floresiensis would be nothing less than a revolution in the understanding of human evolution. It's not just that a new species has been claimed to be found, itself an event of seismic proportions. Conventional anthropological wisdom holds that animals, in the absence of big predators, shrink to adapt to life on small, closed habitats like Flores, a phenomenon known as island dwarfism. Humans, however, are thought to have evolved linearly, developing bigger bodies and brains. H. floresiensis, relatively modern yet small—but not a Pygmy, according to its supporters—explodes that theory. "[It'd] go completely against the flow of human evolution," says Thorne. "This would undo everything that we are." Even if the island-dwarfing process did indeed shrink H. floresiensis, says Robert Martin, curator at the Field Museum in Chicago and author of a widely cited textbook on human evolution, the grapefruit size of the brain is too small. "Brains do not shrink proportionally to bodies in a species but remain relatively large," says Martin. "That's why the heads of small dogs, for example, are proportionally large for their bodies compared with larger dogs. To get a brain this size, H. erectus would have to have shrunk to about 3% of its previous 60-kg size. That's about the size of a house cat's." Martin says one thing would persuade him—more physical evidence: "Show me eight more similar skulls from the site and I'll shut up."

The argument should have been at least partly settled by a study conducted by a group of Australian, U.S. and Indonesian scientists (including Brown and Morwood) earlier this year that used computer tomography and 3-D reconstruction techniques to model the brain of H. floresiensis. The resulting paper, published in the journal Science in March, contended that the findings supported the theory of a new species and strongly downplayed the possibility of a disease like microcephaly playing a role. But critics remained unconvinced, citing flaws in the study, such as the suitability of skulls used for comparison. Even one of the paper's authors, Washington University radiologist Charles Hildebolt, conceded that secondary microcephaly (the type not inherited but acquired during life) could not be ruled out.

Controversy over the existence of Pygmies in Indonesia's numberless islands is centuries-old. Writing in the 14th century, Marco Polo described how natives of Sumatra would try to sell the mummified bodies of Pygmies to visitors. But, wrote Polo, "'tis all a lie and cheat. Those ... little men ... are manufactured on the island. There is a kind of monkey on the island which is very small and has a face just like a man's. They take these and pluck out all the hairs except on the beard and chest and then they dry them and stuff them and daub them with saffron until they look like men."

In the village of Rampasasa, Viktor Jurubu harbors no such doubts. He has the floor again and is recounting the story of how Paju, a famous warrior, ran into one of the "normal" people in the woods one day while out hunting. "This beautiful lady lit a fire and cooked the wild boar Paju had killed," Jurubu says. "She wanted to marry him and knew she could tempt him with the taste of cooked meat. He did like the taste, so he agreed to marry her and come out of Liang Bua with the rest of the tribe, founding a new village."

And the bones in the cave? "Of course, they were our ancestors," says Jurubu, with a touch of rheumy indignation. "They must have retreated into the cave after a hunt and got caught there when the river rose. Who else could it be?" That's proving to be a question for the ages.