We are all Africans under the skin

San Bushmen, Kalahari Desert, Namibia 

In these faces lies the secret of all our origins, if you believe geneticist Spencer Wells. It all sounds extremely plausible to me.

Wells spent 10 years, and studied 50 groups of people, trying to trace a genetic "spelling mistake" or marker in various groups of peoples, and hypothesises that a group of the San Bushmen left Africa around 50,000 years ago and followed the coastlines all the way around the Middle East, India, South East Asia and across the final stretch of water by boat to Australia. The marker was found in Australian Aborigines, as well as in the Dravidians of India.

It was probably drought that led the Bushmen to leave in the first place, and the ice age in Europe - where his Indian descendants had migrated - that led them across the great continent of Asia, crossing the iced-over Bering Straits into the two continents of America.

Wells' theory has its fair share of detractors, but it does show that we are now able to use much more sophisticated technology in the service of discovering more about our origins. In fact, there is a powerful case for a multi-disciplinary approach to the whole thorny question of the origin of homo sapiens involving the paleoanthropologists, archaeologists, geneticists and historians. You can read more in his book, "The Journey of Man" and an interview.

The attractive thing for me about Wells' theories is the belief that we are all the same underneath. Now we have scientific proof that links all races and colours.

As Wells says, "We are all much closely related than we ever expected. Racism is not only socially divisive, but also scientifically incorrect. We are all descendants of people who lived in Africa recently. We are all Africans under the skin."