DNA ties us all together; we share ancestry with barracuda and bacteria and mushrooms, if you go far enough back.

Imagine you're copying a very long document, and occasionally you'll put an A where there should be a C. And that mistake has been translated down through the generations, and more mistakes have accumulated. So the longer the lineage has been in existence, the more mistakes the sequence is going to have.

Taken with the archaeological data, we can say that the old hypothesis of an invasion of people - not merely their language - from the steppe appears to be true.

Every drop of human blood contains a history book written in the language of our genes.

DNA ties us all together; we share ancestry with barracuda and bacteria and mushrooms, if you go far enough back.

We are all Africans under the skin.

The greatest history book ever written is the one hidden in our DNA.