Two hundred years after the birth of Charles Darwin, genetic tests on his own family have reinforced his theory that the human race originated in Africa.
As part of an international genetics project, Darwin's great-great-grandson, Chris, submitted a DNA sample to an eminent team of researchers.
Their findings, announced in Sydney yesterday, shed new light on the origins of the British scientist whose works, including The Origin of Species, established the radical concepts of evolution and natural selection.
The team - which is conducting genetic tests worldwide for the Genographic Project, an attempt to fill in gaps in knowledge about man's migratory history - said yesterday that Darwin's ancestors were among a group of homo sapiens who left Africa about 40,000 years ago.
They travelled to the Middle East and Central Asia, then Europe, riding out the last Ice Age in Spain before moving north.
Chris Darwin, who moved to Australia in 1986 and lives in the Blue Mountains, west of Sydney, said he had been intrigued to discover that his forebears were among the first humans to leave Africa.
"I failed my biology exams at school, so I didn't inherit Charles's scientific ability," he said.
"But I have always clung to the hope that I had inherited his adventurous ability, his wish to go over the hill and see what's on the other side."
The 48-year-old took part in the first Round Britain Windsurf Expedition and hosted the so-called World's Highest Dinner Party, held at 6800m, on a mountain peak in Peru - an event only marred by the wine freezing and two guests suffering hypothermia during dessert.
Chris Darwin, who is a canyoning, abseiling and rock climbing guide in the Blue Mountains, said his ancestor would have been pleased to hear that his theories had been confirmed.
"He probably would have breathed a sigh of relief that he got it basically right, and maybe he would have been amazed by the amount of detail we can get by looking at our genes. Back then, genetics wasn't understood at all, and I think he would have been absolutely fascinated."
The Genographic Project, a joint initiative of National Geographic and IBM, is the largest survey of its kind. To date, it has analysed more than 350,000 DNA samples, many from indigenous groups and people with traditional lifestyles. Its aim is to direct "a zoom lens on who we are and how we moved around the world".
The Darwin family are from one of the most common European male lineages, known as Haplogroup R1b. About 70 per cent of men in southern England belong to that group.
Chris Darwin said of his own test results: "This has given me new insight into who I am, but also into the human race. We are all one big family, and like all big families there are tense moments but it's worth sticking together."