A brief history of mankind (including a new chapter)

The discovery of Homo floresiensis has turned the world of anthropology upside down. Steve Connor weighs up the implications

The complicated history of man's origins has become even more complicated with the discovery of a new and extraordinary member of the human family - pygmy-sized people living in splendid isolation until at least 13,000 years ago.

The complicated history of man's origins has become even more complicated with the discovery of a new and extraordinary member of the human family - pygmy-sized people living in splendid isolation until at least 13,000 years ago.

Homo floresiensis grew no more than about 3 feet tall with a brain the size of a grapefruit, but the most startling aspect of the discovery is that the species survived for so long at a time when our own species was busy colonising every corner of the planet.

Finding a partial skeleton of a female in a limestone cave on the remote Indonesian island of Flores has overturned many of our preconceived ideas of how Homo sapiens became the only human species to dominate the Earth.

Our closest living relative is not human at all, but an ape. We last shared a common ancestor with the chimpanzee some 7 or 8 million years ago, and this species certainly evolved somewhere in Africa.

At various points in the subsequent history, our ancestors began to walk on two legs, grew larger brains, controlled fires, made tools, developed language and eventually complex culture and rituals - all essential ingredients for what makes us human.

Much of the greater part of human evolution took place in Africa, producing a surprisingly wide variety of lineages, many of which were not on the direct line leading to modern humans.

Bipedal walking, stone tools and primitive speech all evolved in Africa. Then, about 2 million years ago the first humans emerged from the continent to colonise the Asian landmass.

These were members of the Homo erectus species, whose descendents left their mark as far apart as Georgia, China and Java. They seemed to have been successful colonisers, but the conventional view is that they died out a few hundred thousand years ago, before or immediately after the second great wave of colonisation out of Africa.

This time, about 100,000 years ago, the migration was by our own species, H. sapiens. With larger brains, better language skills and increasingly sophisticated tools, it was thought that H. sapiens quickly displaced our older cousin - until now.

H. floresiensis, or Flores Man, may have been the size of a hobbit with a brain not much bigger than that of a chimpanzee, but he was intelligent enough to hunt pygmy elephants the size of ponies and to survive on his isolated island for tens of thousands of years.

The team of Australian and Indonesian scientists involved in the discovery believe that Flores Man may have evolved from a much larger group of H. erectus who somehow found their way to the island.

It begs the question of how they got there, because Flores was never connected to the Asian landmass. It is possible that H. erectus may have been smart enough to build bamboo rafts.

Bert Roberts, of Wollongong University in New South Wales, who dated the skeletal remains, said that one of the most intriguing aspects is the possibility that Flores Man may explain local folk tales about pygmy apemen.

"The tales contained the most fabulous details - so detailed that you'd imagine there had to be a grain of truth in them," Professor Roberts said.

A character called Ebu Gogo, which means "grandmother who eats everything", bears many remarkable similarities to Flores Man.

"The anatomical details were fascinating. Short, about 1 metre tall, long-haired, pot-bellied, ears that slightly stuck out, a slightly awkward gait, and longish arms and fingers - confirmed by our finds," Professor Roberts said.

"They murmured at each other and could repeat words back verbatim. They could climb slender-girthed trees, but were never seen holding stone tools or anything similar, whereas we have lots of sophisticated artefacts in the H. floresiensis levels at Liang Bua," he said.

"That's the only inconsistency," he said.