Friday 1 June 2007

Martin Jones: The Molecule Hunt - Archaeology and the Search for Ancient DNA (2001)

Published: Penguin, 2001

In the last two or three decades, modern scientific advances have led to a revolution in archaeology, much of which will be to an extent familiar to watchers of TV shows such as Time Team, which make extensive use of techniques from geophysics to investigate remains which are still buried. But the biggest change is probably due to the use of biochemistry to find out more about the minutiae of past lives and shed new light on long standing questions. This too has been the subject of television programmes; I have seen at least two which aimed to find out what proportion of the British have Celtic, Roman, Saxon, Danish or Norman ancestry. Pop science like this aside, what has the impact of modern biology been on the study of the past?

Martin Jones is in an excellent position to answer this question, as first George Pitt-Rivers Professor of Archaeological Science at Cambridge, and a pioneer of this field. Most of the book is devoted to the message that the traditional big pictures of archaeology developed in the early twentieth century (ideas about migrations, the domestication of animals, the spread of cultures and the Neolithic revolution) are massively over-simplified; this seems to be the major lesson learnt from the new techniques. These major insights are clearly explained, though the complexities of domestication events (basically answers to the question of when and where animals and plants were domesticated) are somewhat confusing due to a desire to include a large number of different scenarios for the different species.

However, I found the minute details which were previously unknowable that have been discovered with biological evidence to be much more fascinating. There was one story about a collection of bodies of medieval nobles exhumed from a German church, which it was possible to identify. There was one count who had no sons, until late in life his wife surprised him. However, DNA analysis showed that he wasn't related to his supposed son and heir. This is something that has obviously been thought about before - I remember reading one analysis that suggested that 10% of official father/son relationships were likely to be wrong, if results from twentieth century surveys on adultery were extended back into the past - but of course it makes something of a mockery of the idea of a royal or noble line of descent. There is always the possibility that the supposed father knew of the parenthood of the child, and accepted the baby as his for political reasons. Determining the real attitude of the count is something that even these new techniques cannot do.

More touching is the story of two communities, one by the sea and the other inland. Analysis of the bodies buried at the inland community showed that one man had, just before his death, been eating a seafood diet which would have been impossible if he had been living there. He must have been a recent arrival, who was buried with as much care as was reserved for the long term inhabitants despite his alien origin.

DNA is obviously the best known, and probably the most important biological molecule discussed in The Molecule Hunt. But Jones does not let his subtitle prevent him from looking at other indicators in biological remains - the second example quoted above does not depend on DNA. Generally, the science is explained clearly, and the story is well told. There is one moment which reads a little awkwardly, though I can see why Jones says what he says: he comments that in the sixties, pottery finds were carefully washed to remove the dirty residue; today, you see projects where the pottery is destroyed in order to make the residue accessible. It is a measure of just how far things have changed, but he says it in a way which is so artificial seeming that it robs it of impact. This short anecdote is atypical of the writing in the rest of this excellent book.

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