by Bryan Sykes
I made the settlement date calculations, as I had in Ireland, for both the paternal and the maternal ancestors. There was still a wide gap between the male and the female side. The ages of the mDNA clans varied between Ursula at 9,200 years, slightly older than in Ireland, and Jasmine, again the youngest at 5,000 years. The paternal clans were slightly older than in Ireland, but still much younger than the maternal dates. There was no immediate answer to what this meant; indeed by this time I had more or less decided to wait until I had surveyed the entire Isles before trying to make sense of it all. But to what extent had the Picts been replaced by the Dalriadan Celts, the Gaels from Ireland? To try to find out we need to move away over the mountains that separate Pictland from our next destination – the Celtic west.
The gradual colonization of the west from the Irish kingdom of Dál Riata during the first half of the first millennium AD, and the consolidation of their Gaelic kingdom in Scotland following their defeat by the Ui Neill, had an immense cultural impact in Scotland. As we have seen, the language changed from the P-Gaelic of the Picts to the Q-Gaelic of the Irish and, on the accession of Kenneth MacAlpin in 843, Gaelic political dominance was complete.
In the west, one question which our genetic analysis could hope to answer was the degree to which the arrival of the Dalriadan Celts from Ireland displaced the Pictish inhabitants of the region. But there is also another factor to bear in mind, and that is our old friends the Vikings. The whole of the west coast and the Hebrides were repeatedly raided by Vikings from the first attack on the monastery of Iona in 795. If the experience in Orkney and Shetland is anything to go by, we should expect to see evidence of a Viking presence among today’s inhabitants of the west coast and the islands.
When we were collecting our samples from the west coast and from the Hebrides, there was a distinctly different response to my questions about people’s own ancestry. In Shetland the last thing men, in particular, wanted to see in their genes was the signal of an Irish ancestry. In the Western Isles, and along the west coast, there was still a certain arcane thrill at the possibility of a Viking ancestry, but this was eclipsed by an affiliation with a Celtic past, whatever that actually meant. People were keen to expose an Irish ancestry, if there was one, but most showed no real interest in the prospect of being of Pictish descent. And yet that was the most likely outcome, since it is almost always, in my experience, the earliest occupants who dominate the gene pool of a region. The later arrivals may get all the headlines, but it takes a lot to displace indigenous genes, especially on the female side. Thanks to the Scottish Blood Transfusion Service, we travelled to donor sessions from Thurso in the far north, along the west coast to Ullapool, Gairloch and Fort William, then south to Oban, Lochgilphead at the top of the Kintyre peninsula and right down to Campbeltown at the very end. We travelled over the sea to the Western Isles and across the bridge to Skye. We saw the land in all its moods, from brilliant sunny days when the bright hills shone in the sunlight to furious tempests when wind and rain lashed along streets and through doorways.
Not even the foulest weather prevented the calm progression of the donor sessions, even when the rain was coming in through the windows of community centres that had seen better days. Attendance by the donors was just as high in the bad weather as in the good. In Grampian, almost everyone coming to the donor sessions had been born nearby, and so had their grandparents. In this respect, the most stable place we visited was Huntly in rural Aberdeenshire, where 78 per cent of donors had all four grandparents born close by. In the west this figure was quite a bit lower, and there was a noticeable proportion who had moved into the area in the recent past, mainly from the towns of the central lowlands or from England. Since the project covered the whole of Britain, practically everybody could contribute to the outcome, even if they had only recently arrived in their current locality. It also worked both ways. In and around Glasgow, Edinburgh and London we often encountered donors whose ancestors had come from the west of Scotland and where, for the purposes of the genetic map, they could be confidently placed.
What of the results? We were becoming very adept at identifying Viking DNA and, sure enough, we found plenty of it. In Caithness and along the stunningly beautiful north coast from the Kyle of Tongue to Loch Eribol and Durness we found, by the same tests we had used in Orkney and Shetland, that 15 per cent of the DNA was Norse in origin. Like the Northern Isles, this was true both of Y-chromosomes and of mitochondrial DNA, so it looked as though it was by establishing family-based communities that the Vikings came to settle here, however unlikely this sounds in relation to their folk memory as bloodthirsty plunderers. However, in the Western Isles and Skye, the genetic evidence for a more typecast male-dominated Viking colonization began to emerge when we looked at the results.
There are twice as many Norse Y-chromosomes in Skye and the Western Isles as there are Norse mitochondria; 22 per cent of Hebridean Y-chromosomes, but only 11 per cent of mitochondrial DNAs, had a Norse origin. The further down the west coast, the lower the Viking component became until, in Argyll, it was down to 7 per cent for Y-chromosomes and only 2 per cent for mitochondria.
The diminishing Viking input and its increasing asymmetry between the sexes as we travel down the west coast seems to me best explained by a gradual process of Viking settlement from the early bases in Orkney and Shetland. Some men took their women with them, or returned to Orkney to bring their families once they had laid claim to a plot of land; others intermarried with local Gaelic or Pictish women. In general we found the same detailed Norse Y-chromosomes along the west coast and in the Hebrides as we had already discovered in the Northern Isles. It really didn’t look as though there had been a rush of fresh arrivals from Scandinavia.
If that was the level of Norse DNA, what of the rest? Could we assign this to Celtic or Pictish origin? For this, I made a start by comparing our results from the Pictish regions of Grampian and Tayside with the west coast locations. I could tell straightaway that they were substantially different. Not only that – there was also a big difference between the three regions of the west. Much as I had divided Pictland into Grampian and Tayside, so I split the west into three. They were the Highlands from Durness to Fort William, then from Oban south to Kintyre, which I grouped together as Argyll, and, thirdly, the Hebrides, which combined Skye and the Western Isles.
On clan comparisons alone, the Hebrides stood out as very different from the other two. Argyll, at this crude level, was far more like the Pictland regions of Grampian and Tayside than the Hebrides. The Highland coast was somewhere in between. Even when I removed the Norse DNA, the picture was the same. At the greater level of detail revealed by the precise sequences, in the case of the mitochondria or the profiles of the Y-chromosomes, the stark differences between the regions still stood out. For the mitochondrial comparisons, on the scoring system of similarity that I introduced in Pictland, which goes from 0–100 (the higher the score, the greater the similarity), Argyll vs Pictland scored 60, the same score as Argyll vs Highlands but much higher than the Hebrides scored in this equation of similarity with either of them. However, the Y-chromosomes told a different story. The Argyll Y-chromosomes were much more like their Hebridean counterparts than those in the Highlands.
If your head is spinning, you are feeling just as I did when I first tried to decipher these results. It seemed to be going so well. We had identified the genetic legacy of the Vikings and we had found that, just as the archaeology and history leads us to expect, they did not settle in Pictland to any extent. We had seen their diminishing genetic impact as we travelled further and further away from their forward bases in Orkney and Shetland. Until then everything made good sense. But then, the simple story, based on our historical assumption, began to unravel. Far from Pictland being genetically distinct from the Celtic heartlands of Dalriada and Argyll, they were remarkably close, on the maternal side at least. However, this similarity is not reproduced by the Y-chromosome, where Argyll has a low gene-sharing sco
re with Grampian, even after the Norse component has been subtracted.
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 extremely 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.
