Haplogroup I – North Europe, Balkans
Haplogroup I represents the largest and oldest haplogroup throughout Europe with few exceptions. The origins of haplogroup I are thought to begin with haplogroup IJ — from the Middle East as far back as 40,000 years ago. The mutation of Haplogroup I occurred some 25,000 years after the formation of haplogroup IJ. I includes Cro-Magnons who were also thought to belong to IJ.
In short, some 40,000-30,000 years ago, the central ancestors from haplogroup IJ migrated to what is now Scandinavia and Finland and then mutated into haplogroup I about 25,000 years ago.
Haplogroup I and its Major Subclades
There is a lot of information that the subclades provide. They tell the story of geologic events such as glaciation and other barriers to migration. They also tell the story of cultural shifts in humanity.
Haplogroup I1 — Northern Europe
Populations in Scandinavia and Finland often hold more than 35 percent of the mutation that makes up I1 and the Norse ethnicity. The I1-subclade is the Viking and Germanic story and follows in relationship to the Germanic language.
In terms of time, I1 began some 20,000 years ago. Genetically, I1 holds 25 plus mutations within the Y chromosome; a sign that genetic bottleneck events occurred. Life, in those early years, was not easy for the people who made up I1.
To paint a picture of I1’s life, understand, that much of Scandinavia was glaciated. The last glacial period for that area began some 100,000 years ago during the Pleistocene and ended 12,000 years ago. So haplogroup I experienced the last ice age and during that time, conditions caused their gene pool to bottleneck — shrinkage of available genetic stock. This is what led to the rise of the subclade I1 and its 25 mutations.
Distribution of I1
From DNA testing, it is clear that I1 migrated. The Y-Chromosome markers show up the heaviest in Scandinavia and spread outwards to include the British Isles, the lowlands of Europe, and down into Germany, Italy, and even Spain. There is also evidence that I1 were hunter gathers, especially during the ice age. As the ice receded migration occurred and I1 mixed with G2a clades — Neolithic farmers from the Linear Pottery Culture (LBK.) That is important because it represents a shift in genetics. The bonding of cultures helped I1 and I2 to survive for there is also evidence that I2 integrated with G2a. Much of the dispersion of I1 and I2 likely occurred during the Mesolithic while the G2a clade also expanded as the ice sheets receded.
Haplogroup I2 – Balkans
The I2 subclade appeared during the Late Paleolithic. It has three major mutations, L460, L416, and L596 or I2a, I2b, and I2c. I2b and I2c appear to have died out before the Mesolithic era began. I2A, however survived and became mutated twice in to I2a2 and I21. I2a2 which dispersed throughout Northwestern Europe and Central Europe. Whereas, I21 dispersed throughout Western Europe and Eastern Europe both during the Mesolithic. By the time the Neolithic era began, the mutations for I2a2a remained in Northwestern Europe and entered the British Isles as L126, and L1193 during the Bronze age. I2a1 continued to spread within Western Europe during the Neolithic as I2a1a and continues through the Bronze age with the last clade being Z106. I2a1c was last noted at L1295 and ended sometime before the Bronze age. I2a1b, in Eastern Europe also hit the British Isles as L161.1 during the Neolithic and died out. While I2a1b had three mutations, L161.1, L621, and L41.2. L41.2 mutated to L147.5 and died out at the beginning of the Bronze Age. L621 mutated to CTS4002 at te beginning of the Bronze age and mutated again to L147.2. L147.2 mutated to CTS1028 and died out during the Bronze Age in Eastern Europe.
What all of this shows us is the rise of anatomical modern man. I2a were Cro-Magnon or homo sapiens sapiens and range from 35,000 to 10,000 years ago. 10,000 years ago was almost the time when farming became a major trait within humanity. Prior to that humans were hunter-gatherers until the Neolithic.
Clade IJ came from the Middle East and became I1 in Scandinavia and I2 around modern day Croatia. The mutation tell a wonderful story some of which is fictionalized in the novel “Clan of the Cave Bears.” To read this history from bits of data, bone, and DNA is to wittiness the power of evolution, natural selection, and survival of the fittest. Both I1 and I2 survived against incredible odds, and yet not all of the mutations made it. That is the power of natural selection on an individual basis and evolution on a societal basis. Such a story points out that as a species we are ever changing. The question is now, who do we become next?
15 Sep 2016 / rarikola / 4
Tags: Balkans, British Isles, Bronze Age, Cro-Magnon, Europe, genetic bottleneck, genetics, Germanic, Germany, Haplogroup I, Haplogroup I1, haplogroup IJ, I2 Subclade, ice age, Italy, Mesolithic age, Middle East, Neolithic farmers, Northern Europe, Scandinavia, Viking