The Scots: A Genetic History BY Alistair Moffat and James F Wilson Birlinn, 256pp, £16.99
The trouble with prehistory, as far as most historians are concerned, is first of all that there's such a lot of it, and secondly that there's so little that one can definitively say about the people who lived in it.
Since the 1960s, the application of genetics to history has allowed us to say a little bit more: since the 1990s we've learnt that we're all Africans, if we go back far enough, and since 2,000 studies of mitochondrial DNA have allowed us to find out the route most of us took to get from there to wherever we live now. Left in the hands of the geneticists, however, this would be science, not history. Without writers able to imagine the past the first peoples walked through, their lives would be dead on the page: indeed, they wouldn't be lives at all, merely a splattering of pie-charts showing distributions of Y-chromosome groups and abstruse patternings of mtDNA variations.
What prehistory needs is someone with the seemingly contradictory abilities of being able to explain cutting-edge research in layman's terms and an imagination strong enough to think beyond a merely modern mindset.
Add in a knowledge of how time has altered the landscape, an awareness of the latest archaeological discoveries, an understanding of how ancient languages offer extra clues to the deep past and you are beginning to get close to what is required. As far as the general reader is concerned, even that mightn't be enough. Having an eye for a good story and a keen ear for the telling phrase can count for just as much as everything else.
In books such as The Faded Map and Before Scotland, Alistair Moffat has already synthesised a variety of disciplines to show with the required verve and stylishly demonstrated that the paucity or complete absence of the written record doesn't prevent us knowing quite a lot about our distant ancestors' lives. Here, guided by James Wilson's researches into Scottish genetic history, he tackles one of the biggest stories possible: linking up the story of the earliest Scots to the earliest men.
It helps that he is a great phrasemaker. So DNA markers are "a chemical archive of our history", its codes "like the letters in the words on this page", and Doggerland, now submerged beneath the North Sea but once a land with its own lakes and river systems, is "an Atlantis in the East". But he is also wonderfully able to communicate the epic element to this story - which matters because that's precisely what man's survival has been.
For survival has been a close-run thing - never more so than in the aftermath of the supervolcano eruption in Sumatra 70,000 years ago, "the worst in 25 million years" which might have wiped out all but 5,000 human beings on the planet.I'm not sure how the numbers of survivors are worked out, but they are impressively small. All people that on earth do dwell - apart from those in Africa - are apparently descended from a mere 300 who made the journey out of our home continent. Again, the numbers are unexplained but a cause of wonder.
As is the peopling of Scotland. All Scots, Moffat reminds us, are immigrants, but DNA evidence allows us for the first time to be more precise about from where. It must be hard, you can't help thinking, for any geneticist to be a racist, given that we're all originally African. But even racist nostalgia for a once-pure bloodstock takes a battering from genetics. In Scotland's case, for example, the people here longest were originally from either side of the Pyrenees, while most of the rest of us are basically Irish. As far as the Romans are concerned, they came, saw and conquered most of Britain, but genetically speaking, they hardly left much of a trace behind.
In years to come, when more people know (as Jim Wilson already does) the full six-billion letters of their genetic code, we might be able to be very specific about the places that we come from. We only have a few signposts at the moment, but they are important ones.
And in placing them firmly on the landscape of Scottish pre-history, Moffat and Wilson have marked out a truly fascinating route that many more people interested in this mongrel nation's past will follow in the future.