Re: Y-DNA Warehouse Tree Tech Demo
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Elizabeth,
You asked whether Stout indicated if the whole island was affected?
What he says is 'pollen analysis? tells not only about vegetation but also about the progress of agriculture and population, At the end of the Iron Age there was a marked downturn in human agricultural activity that led to the regeneration of woodland. This Late Iron Age Lull (as it is known) must indicate a marked decline in population: on the Aran Islands it began about 100 AD and lasted for 400 years; in Sligo the lull began around 80 BC and lasted for 430 years, to AD 350; and it lasted from AD 110 to 420 at Clara Bog in the Irish midlands. Supporting evidence comes from dendrochronology. A 'strange gap' in building construction exists between 40 BC and AD 250, corresponding to the pollen analyst's Late Iron Age Lull.'
John.
The Book of Invasions (written? in the 11th century) says the Partholonians, the second group to settle in Ireland, died from a pestilence.? You can¡¯t help but wonder if a plague/pandemic (a real one) occurred during that 40 BC to 250 AD period and was incorporated into the myths.? ? Might our FGC11134¡ gents have survived?? Or might a second wave of that haplogroup arrived later? ? John, does Stout indicate if this lull affected the whole island equally?? I know you shared with me privately last month that Stout believed that Ogham was developed in west Wales rather than southern Ireland.? I¡¯m getting that book¡ ? Elizabeth ? ? ? A potential contributor to a SNP bottleneck might be the phenomenon known as the 'Late Iron Age Lull'? Discussed briefly (since it antedates his main focus) by Dr Matthew Stout in his 2017 book entitled Early Medieval Ireland 431-1169, he points to a marked downturn in human agricultural activity in Ireland from around 40 BC to 250 AD as evidenced by pollen analysis. He suggests that this must have been associated with a marked decline in population, further supported by a 'gap' in building construction over the same period. This does not seem to have been associated with a deteriorating climate - indeed the corresponding period in Britain is known as the 'Roman Warm Period'. It certainly could provide both a SNP bottleneck but also a marked incentive for some to 'investigate' opportunities on the eastern shore of the Irish Sea? ? On final point, if the archaeological evidence doesn¡¯t point to an Iron Age invasion, or if the linguistic evidence doesn¡¯t point to any significant interruption or linguistic revolution in primitive insular Goidelic, then there is a problem ¨C the sequence of events doesn¡¯t fit. The only solution to this problem of such a large continuous snip block is a significant bottleneck in CTS4466, with the modern snip block perhaps representing the survivors. As such, if the modern Irish tree branch has been interrupted by a significant bottleneck, then that implies that the first CTS4466 man in Ireland was a lot older than 250AD. The MRCA of the modern group is just descended from a branch line that survived, the collateral lines perished and as such are absent on the modern phylogenetic tree. If so, it really isn¡¯t possible to date when CTS4466 arrived in Ireland to any accurate degree. ??? ? I suspect I¡¯m not delivering any earth shattering news ¨C the conclusion is obvious. ? ? ? ? EXTERNAL EMAIL: This email originated from outside of NUI Galway. Do not open attachments or click on links in the message unless you recognise the sender's email address and believe the content is safe.
R?OMHPHOST SEACHTRACH: Th¨¢inig an r¨ªomhphost seo as ¨¢it ¨¦igin taobh amuigh de O? Gaillimh. N¨¢ clice¨¢il ar naisc agus n¨¢ hoscail ceangalt¨¢in mura n-aithn¨ªonn t¨² seoladh r¨ªomhphoist an tseolt¨®ra agus mura gcreideann t¨² go bhfuil an t-¨¢bhar s¨¢bh¨¢ilte. ? On another point, if CTS4466, particularly R-A541, Irish Type II, is the dominant snip marker in the Southwest of Ireland, 250AD might seem a little recent to establish a founder effect. The other possible chink in the armour is language ¨C Ogham stones might be identified with CTS4466, but we know they were written in primitive Irish and not in P-Celtic Brythonic, as might be expected if CTS4466 came from either Wales or Gaul. ? I take your point though, yFull estimates the TMRCA of A541 to 1750 ybd. ? Best, ? Neil ? From: O'Brien, Neil
Sent: Monday 6 September 2021 17:24
To: [email protected]
Subject: RE: [R1b-CTS4466-Plus] Y-DNA Warehouse Tree Tech Demo ? If we¡¯re agreed that CTS4466 probably didn¡¯t form on the island of Ireland, but in Wales ¨C or perhaps further afield, 250AD would be a significant date. It would mean that the arrival of the clade into Ireland coincides with the Irish Iron Age, and most Irish archaeologists have long argued that there is no evidence for any significant population incursion into Ireland in the Iron Age. Mind you, they said the same about the Bronze Age too¡¡¡ ?? ? ? EXTERNAL EMAIL: This email originated from outside of NUI Galway. Do not open attachments or click on links in the message unless you recognise the sender's email address and believe the content is safe.
R?OMHPHOST SEACHTRACH: Th¨¢inig an r¨ªomhphost seo as ¨¢it ¨¦igin taobh amuigh de O? Gaillimh. N¨¢ clice¨¢il ar naisc agus n¨¢ hoscail ceangalt¨¢in mura n-aithn¨ªonn t¨² seoladh r¨ªomhphoist an tseolt¨®ra agus mura gcreideann t¨² go bhfuil an t-¨¢bhar s¨¢bh¨¢ilte. ? The thing about the age estimates is that you only count SNPs that fall inside the regions where there has been work to study the rates of mutations.? While there are 20 equivalent SNPs only 15 are used for dating the branch. As far as the 1700 years that Elizabeth was asking about being different¡ that¡¯s in the same ballpark I¡¯m pretty sure I¡¯ve always been. ?1950 - 1700 = 250AD. James ? ? This time/SNP thing intrigues me greatly (as I assume it does others). Let¡¯s do a little kindergarden math: Elizabeth notes that James has?CTS4466 formed 3,000 ybp and its¡¯ TMRCA at 1,700 ybp. There are 20 SNPs in the CYS4466 block making the time between forming and the TMRCA yield an average SNP rate of (3000-1700)/20 = 65 yrs/SNP. There are two Lee¡¯s near me who, with their 2 private variants, are some 37 SNPs below CTS4466¡¯s TMRCA. If we assume that this takes us all the way to the ¡®present¡¯, then using James¡¯s value of 1700 ybp for that time frame, we get another estimate: 1700/37 = 45.9 yrs/SNP. Of course, the two Lee¡¯s likely do not lead us up to the present; there are more SNPs to be discovered, thus making the ¡¯37¡¯ larger and the yrs/SNP smaller. Then if we do these together, we get 3000/57 = 52.6 yrs/SNP. And that¡¯s a max number. So 50 yrs/SNP is perhaps a better guess.
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