On 27 October 2004, a team of scientists in Australia and Indonesia revealed the discovery of a 1-metre-tall, tiny-brained relative of modern humans. They described it in two Nature papers1, 2 as a new species, Homo floresiensis. It had lived as recently as 18,000 years ago on the Indonesian island of Flores.

For the tenth anniversary of that announcement, Nature brought together four scientists to remember the discovery, which continues to boggle minds. In particular, scientists still debate the evolutionary origins of the hobbit — as the find came to be known — and some even contend that it is a diseased Homo sapiens rather than a separate species.

"It's at the wrong place, at the wrong time. It looks completely odd," says Bert Roberts, a geologist at the University of Wollongong in Australia, who helped to conceive the dig at Liang Bua cave, which began in 2001.

The four experts, in addition to Roberts, are: Thomas Sutikna, an archaeologist at the University of Wollongong who was overseeing the dig when the hobbit was discovered; Dean Falk, an evolutionary anthropologist at Florida State University in Tallahassee, who led the team that described the brain of H. floresiensis on the basis of impressions left in the fossil skull; and Chris Stringer, a palaeoanthropologist at the Natural History Museum in London, who was among the first outside scientists to learn about the discovery and has been trying to make sense of it ever since.