by Bryan Sykes
To me this is the familiar signal of maternal continuity. What we have here, I think, is the imprint of Scotland’s Pictish ancestry, on the maternal side, spread more or less uniformly across the land. This is the bedrock of Scottish maternal ancestry on which more recent events have been overlaid. The maternal gene pool is more or less the same in Pictland, in ‘Celtic’ Argyll and in the Highlands. In Orkney and Shetland, the Pictish bedrock has been overlain by a more substantial and identifiable Norse settlement than anywhere else in Scotland, but it is still there nevertheless.
On the male side, we can see plainly what must be the Pictish bedrock in Grampian and Tayside, but in Argyll it has been substantially overlain by new arrivals. The Argyll Y-chromosomes are in between the Irish and Pictish values and, although these estimates are approximate, a 30–40 per cent replacement of Pictish by Gaelic Y-chromosomes would account for this. It is much harder to be accurate in this case than it was in judging the Norse contribution to the Northern Isles because of the basic similarity between Irish and Pictish Y-chromosomes which, incidentally, makes it almost impossible to detect any genetic effect of the Ulster plantations. However, the genetic signal, as far as I can judge, points to a substantial and, by the look of it, hostile replacement of Pictish males by the Dalriadan Celts, most of whom relied on Pictish rather than Irish women to propagate their genes. The reason I cannot be more certain is itself very relevant to the myth of the Picts. It is precisely because they are genetically close to the Gaelic Irish that these estimates are so difficult. If they had been a relic people, a genetic isolate, then it would have been easy to distinguish them from Irish Gaels. But on the contrary, it is extremely difficult, from which we can confidently conclude that the Picts and the Celts have the same underlying genetic origins.
Which leaves the Hebrides. Their genetics stand out from the Picts and the Celts and the Norse of Shetland or Orkney. Their DNA-sharing scores are low for all comparisons, and for both maternal and paternal genes. Take away the attributable Norse component and the differences remain. What can be so special about the Hebrides? Let’s take a closer look.
The long line of islands of the Western Isles are battered on their western sides by the pounding of the Atlantic. These islands protect the Inner Hebridean islands of Canna, Rum, Eigg and Skye from the worst of the Atlantic swell–though when I was caught on an inter-island ferry in a gale I thought the violently bucking boat could have done with a lot more protection. The islands are the last stronghold of the Gaelic language in Scotland and had suffered from decades of depopulation even before the Highland Clearances of the eighteenth and nineteenth centuries. The sight of an abandoned village, with the outlines of stone-walled cottages collapsed and overgrown, is always a sad one. But the sheer scale of it only struck me one day last December when I was taking advantage of the few hours of sunlight to have a trip in the car around Skye.
I went, for the first time, to Glen Eynort, near the Talisker whisky distillery at Carbost. The road to Glen Eynort rises from Carbost and then crosses a low pass which leads to the glen with its two or three inhabited cottages, each with a plume of smoke rising straight up into the cold and, for once, still air. As I descended, the sun, very low in the sky, came out and lit up the hillsides which surround the glen. What I saw utterly amazed me. The low angle of the sun transformed every patch of hillside into lines of light and shade. It took me a moment to realize that these were abandoned fields, with the sun striking the ridges and casting a shadow in the furrows. This ancient landscape, glimpsed only because of the low angle of the sun and normally impossible to make out, covered hundreds of acres. The valley must once have been teeming with life but now, save for the three cottages, it was empty, the crofters dispersed to the far-flung corners of the world.
Luckily the depopulation was not complete and the Hebrides are once again thriving. But why are the genetics so unusual? On the maternal side, the striking thing, compared to other regions, is the much higher proportions of clans that, though they certainly occur elsewhere, are much less frequent. These are the two clans of Jasmine and Tara. And these clans carry the unmistakable signature of agriculture. As we saw in an earlier chapter, Jasmine herself lived in the Middle East and her descendants accompanied the spread of farming into Europe. The clan divided into two around the Balkans. One branch followed the Mediterranean and Atlantic coasts, the other crossed Europe overland. The two branches can be told apart by a series of mutations which must have happened after the split. Both branches have the characteristic mutation of all members of Jasmine’s clan of 069 and 126, plus two others at 145 and 261. On its way round the Mediterranean, one branch acquired two more changes at 172 and 222, while on its trek through Europe the other branch gained one extra change at position 231. It is still amazing to me that these tiny changes can tell us so much about the journeys of our ancestors. How one line, hugging the Mediterranean coast, reached Spain then headed north up the Atlantic coast of France, while the other forced its way through the forests and valleys of continental Europe. These mutations illuminate such different journeys. In Ireland, and all along the west coast of Scotland, only the Mediterranean branch of Jasmine is found. The same is true of the Hebrides, and the concentration of these Mediterranean Jasmines in Skye and the Western Isles explains one of the differences.
The other difference is in the clan of Tara. When I first discovered the clan, with my colleagues, it had all the characteristics of a hunter-gatherer origin: a founding date of 17,000 years ago, and a location to the north of Italy among the hills of Tuscany.
When my research group were defending our conclusions about the human past in Europe, and had gathered lots more samples in the process, it gradually became clear that the clan of Tara had, within it, a branch that looked much younger than the rest of the clan. As well as the signature Taran changes at 126 and 294, this branch had additions at 296 and 304. We dated this branch at slightly younger than Tara herself, possibly just within the scope of the spread of agriculture, possibly at the end of the Mesolithic. And it is this Taran branch that dominates the Hebrides.
It seemed to be these two young branches of the two clans, Jasmine and Tara, that were responsible for the unusual genetics of the Hebrides. And both of these branches, the Mediterranean Jasmines and the younger Tarans, had a distinctly seaborne flavour about them. They are spread all along the Atlantic fringe, but rarely inland. This was a definite clue, but the solution was not yet clearly visible. The Hebrides are also unusual in having a very high concentration of members of the Katrine clan, especially on Lewis, where they reach the highest frequency of anywhere in Scotland.
It was during my research on Skye that I stumbled across a genetic phenomenon which, with hindsight, I should have investigated much sooner. At that stage I had already discovered the link between my own surname and a particular Y-chromosome profile. Foolishly imagining that such a link to a common founder would only be found in comparatively uncommon English surnames, it took another year before I realized the same might be true, albeit in diluted form, among Scottish clans as well. My research student Jayne Nicholson and I found a rare Y-chromosome profile in our Skye samples and, when we compared it to others collected at donor sessions elsewhere in Scotland, we noticed that we found it almost exclusively among men with the surnames Macdonald, McDougall and Macalister. It was Jayne who remarked that all three names were said to be descended, according to traditional clan genealogies, from Somerled, the Celtic hero whom we have already encountered. It was Somerled who was responsible for ending the power of the Norse earls of Orkney in Argyll and the Hebrides, and who died at Renfrew during his ill-fated invasion of Scotland in 1164. Jayne set about writing to men with these three names asking for DNA samples, while I contacted the five living clan chiefs whose genealogies traced back to Somerled. They all agreed to help and, I’m very glad to report, all five had inherited the same Y-chromosome that we had seen in the men with the three surnames. Somerled’s Y-chromosome had done extrem
ely well and, thanks to its association with a powerful and wealthy clan, has become very common indeed in the Highlands and Islands, and among Highlanders who have emigrated overseas. Roughly a quarter of Macdonalds, a third of McDougalls and 40 per cent of Macalisters are direct paternal descendants of Somerled. This is not just true in Scotland, but throughout the world; it has been estimated that there are 200,000 men who carry Somerled’s Y-chromosome as proof of their descent from the man who drove the Norse from the Isles.
I am only summarizing here what was an exhilarating search for the legacy of this illustrious Celtic hero because I have written about it at length in Adam’s Curse. Soon after this discovery–which was also paralleled by the Macleods of Skye, though there the linkage was to a different chromosome–I heard about the research on Genghis Khan’s profligate genetic legacy. His Y-chromosome, passed down through generations of emperor sons, is now found in an estimated 16 million male descendants. This might put Somerled’s 200,000 descendants in the shade, but the feeling has grown among geneticists that the Genghis effect could be an important factor in the rise and fall of Y-chromosomes, not only in Asia but in other parts of the world, including the Isles. Recently Brian McEvoy and Dan Bradley from Dublin have found an Irish equivalent to the Macdonalds and the Macleods. Again starting with an unusual Y-chromosome, they noticed its occurrence in a related set of surnames that were linked to branches of the Ui Neill, the clan that had held the High Kingship at Tara, and had expelled the Dál Riata to Argyll. The Ui Neill equivalent of Somerled was Niall Noigiallach, better known as Niall of the Nine Hostages, who lived in the second half of the fourth century AD. This was a time when the Romans were beginning to withdraw from mainland Britain. According to legend, Niall raided and harassed western Britain and specialized in capturing and then ransoming high-ranking hostages, hence his soubriquet. His most famous captive was one Succat, who went on to become St Patrick. Niall’s military exploits carried him over the sea to Scotland, where he fought the Picts who were trying to retake the recent Irish colonies of Dalriada. It was during a raid even further afield, in France, that an arrow from the bow of an Irish rival killed Niall on the banks of the River Loire in AD 405.
Niall was succeeded in the High Kingship by his nephew, Dathi, his father’s brother’s son. This was typical of the Gaelic tradition of derbhfine, the rules of inheritance that chose the new king from among the direct male relatives of the old. This served to ensure the patrilineal inheritance of the High Kingship itself and of the whole clan of Ui Neill. Their hold on the High Kingship was remarkably durable, lasting from the seventh to the eleventh century AD. Brian McEvoy’s and Dan Bradley’s Y-chromosome tests on the Irish showed that a high proportion of men with Ui Neill surnames–names like Gallacher, Boyle, Doherty, O’Connor and even Bradley, as well as O’Neill–shared an identical or very closely related Y-chromosome signature, strongly indicative of direct descent from Niall himself. In the parts of Ireland most strongly associated with the Ui Neill, mainly in the north-west, the proportion of these Y-chromosomes reaches almost one quarter of the male population.
These bursts of Y-chromosome success over a few generations are something to be aware of in our interpretations of the genetic evidence from the Isles. The predictable effect will be to distort the Y-chromosome profile of a region in favour of the local chieftains and also to exaggerate the differences between the regions. We have already seen how this may be happening in that Y-chromosome similarity scores between regions are usually lower than the same comparative score for mitochondria. The only regions that we have so far encountered where the Y-chromosome similarity score is almost as high as the mitochondrial are the two Pictland regions of Tayside and Grampian. If inheritance and succession really were matrilineal, then this practice would indeed neutralize the Genghis effect, since no Y-chromosome could be linked to wealth and power for generation after generation. Another effect will be to reduce the age of a patrilineal clan. If one or a few Y-chromosome signatures come to predominate in a region due to the Genghis effect, they can do so only at the expense of others. These, it follows, are eliminated either because the men who carry them are actually killed, as was the case in the Mongol Empire, or because they do not have their fair share of children, since the Genghis male monopolizes the women in one way or another. The Genghis effect can substantially reduce the variety of Y-chromosomes, so the normal way of estimating the age of a clan in a region by averaging the number of mutations will be distorted. The fewer different Y-chromosomes there are, the fewer mutations will be found, the average will drop, and the age estimate will become artificially younger. The more pronounced the Genghis effect, the greater the distortion and the greater the difference between the true age of a clan and the estimate. To take things to extremes just to illustrate the point, were Genghis Khan’s Y-chromosome the only one to have survived from thirteenth-century Mongolia, only the mutations along his line would have accumulated and the age estimates of Mongolian Y-chromosomes would come out around 800 rather than thousands of years.
Scotland has shown us a bit of everything. Vikings, Picts, Celts, the erratic effects of patrilineal kingship and the ancient bedrock of maternal ancestry. We have discovered that the Viking settlement of Orkney and Shetland was very substantial but also much more peaceful than was previously thought, with as many Norse women as men among the settlers. We now know how to identify a Norse Viking genetic presence anywhere in the Isles. Orkney and Shetland aside, there is a very close genetic affinity between Scotland and Ireland. There has certainly been a substantial settlement from Ireland at some time in the recent past, and the Irish Y-chromosome infiltration into the west of Scotland is almost certainly the signal of the relocation of the Dál Riata from Ulster to Argyll in the middle of the first millennium. We have also made an important discovery about the Picts. Their descendants are still in Scotland in force, yet they are not the weird prehistoric relics that were once imagined. They fit very comfortably into the Celtic bedrock of the Isles and they have been here a very long time. The Y-chromosomes are more diverse in the Pictland regions of Grampian and Tayside than in, say, Argyll or Ireland, and the explanation may have something to do with the tradition of matrilineal inheritance. The Western Isles stand out as being a little different from the mainland. There are Viking genes there for sure, but also strange ratios of the maternal clans. The Western Isles have the highest concentration of Katrines in the whole of Scotland, twice that of the Pictish heartland of Grampian, along with large numbers of a maritime branch of the clan of Tara which has travelled from the Mediterranean.
We now have a very good idea of the basic genetic structure of Scotland and Ireland, two of the three regions of the Isles that are most closely identified with a Celtic ancestry. The third is Wales and to reach it we go south down the west coast, through the North Channel and into the Irish Sea. We sail past the Norse outpost of the Isle of Man and head further south to the distant peaks of Snowdonia, the highest point in the land of the Red Dragon.
13
WALES
The smallest in land area of the four regions of the Isles, Wales has a population of just under 3 million, occupying a country of 8,000 square miles. Like Scotland, Wales is a mountainous country, with a broad upland spine running down the centre from the high mountains surrounding the summit of Snowdon (1,085 metres) to the Brecon Beacons, which rise to 886 metres in the south. Between these, the upland plateaux of the Cambrian Mountains are intercut by river valleys radiating in all directions and emptying the abundant rainfall into the Irish Sea and the Bristol Channel. Like Scotland, Wales is bounded on three sides by the sea, backed by coastal lowlands, and shares a land boundary with England. And, also like Scotland, this border, the Welsh Marches, has moved backwards and forwards according to the successes and ambitions of the rulers on either side.
The archaeological evidence for the earliest settlers is comparatively thin on the ground. There is the ancient tooth from the cave at Pontnewydd in north W
ales that we met in Chapter 1, but at 300,000 years it is far too old to be from a modern human species. At the other end of the country, at Paviland Cave on the Gower Peninsula, the remarkable burial of the ochre-tinted body of the Red Lady showed that Homo sapiens had reached Wales before the last Ice Age, but had been forced to retreat south as the temperature dropped and the great herds left the slowly freezing land.
Precisely when humans returned to Wales is uncertain, but considering how close it is to the Cheddar Caves across the Severn, it is surely likely that Palaeolithic hunters got that far, though they left no trace. There are just a handful of late, coastal Mesolithic sites around the Irish Sea, where conditions were similar to sites in Ireland and on the west coast of Scotland. Life for the early Welsh followed the familiar pattern we have already seen elsewhere in the Isles: a life of gathering shellfish, offshore fishing in coracles and hunting in the wooded slopes behind the seashore. There are Neolithic megaliths in Wales, though none matches the magnificence of the Irish passage graves at Newgrange or the great monuments in Orkney or at Stonehenge. Neither have any neolithic villages like Skara Brae yet been discovered. The earliest houses, round in outline, are isolated. There is some evidence of communal activities around the sites of chambered tombs, the cromlechs, whose stark stones have been stripped of their protective mounds of earth.
The history of Wales reads like a catalogue of struggle and resistance against invasion. The Romans were the first to make a serious attempt to subdue the Welsh after the Claudian invasion of Britannia in AD 43. There were, of course, no national boundaries in those days. There was no country called Wales, nor Scotland, nor England. The only defined territories were those occupied by Celtic tribes, in Wales the Silures in the south, the Demetae in the south-west, the Cornovii in mid-Wales, the Deceangli on the north coast and the Ordovices in the mountains of Snowdonia and Cader Idris. Our only knowledge of these tribes and the lands they occupied comes from what the Romans themselves recorded on their campaigns. How accurate this is, we cannot know.
