A Time Series of Prehistoric Mitochondrial DNA Reveals Western European Genetic Diversity Was Largely Established by the Bronze Age
This study is a further example of the importance of ancient mtDNA finds in understanding the Neolithic expansion and by extension R1b migration paths. It shows a close overlap between H expansion period and the supposed R1b expansion period.
What I have learned from this study is the importance of the Chalcolithic in the expansion and the important role played by H. It also confirmed my theory of the rapid Maritine expansion followed a slower River migration.
"A major unanswered question concerns the roles of continuity versus change in prehistoric Europe. For the first time, genetic samples of reasonable size taken at multiple time points are revealing piecemeal snapshots of European prehistory at different dates and places across the continent. Here, we pull these disparate datasets together to illustrate how human genetic variation has changed spatially and temporally in Europe from the Mesolithic through to the present day. Mitochondrial DNA (mtDNA) haplogroups were determined for 532 European individuals from four major eras: the Mesolithic, Neolithic, Chalco- lithic (late Neolithic/early Bronze Age transition) and Modern periods. The Mesolithic was characterized by low mtDNA diversity. These initial European settler haplogroups declined rapidly in the Neolithic, as farmers from the east introduced a new suite of mtDNA lineages into Western Europe. For the first time, we show that the Chalcolithic was also a time of substantial genetic change in Europe. However, rather than the arrival of new mtDNA lineages, this period was characterized by major fluctuations in the fre- quencies of existing haplogroups. Besides the expansion of haplogroup H, there were few major changes in mtDNA diversity from the Chalcolithic to modern times, thus suggesting that the basic profile of mod- ern western European mtDNA diversity was largely established by the Bronze Age."
"Current understanding emphasizes two different migra- tion routes; a relatively rapid diffusion via a southern route along the Mediterranean coast (associated with the Impressed Ware and Cardial Ware culture), together with a slower north- ern route along the Danube valley into central Europe (associ- ated with the Linearbandkeramik, or LBK, culture) (Guilaine, 1997, 2003; Gronenborn, 1999; Zvelebil, 2004; Guilaine & Manen, 2007). "
"We now have mtDNA data for >100 individuals from the Meso- lithic period (more than ~9000 years before present), the Neo- lithic period (the samples in this study are from the early Neo- lithic, ~9000 - 5500 years before present) and the Chalcolithic period (the transition from the late Neolithic to the early Bronze Age, ~5500 - 3700 years before present)."
"Apart from the ongoing expansion of hap- logroup H, there were few major changes from the Chalcolithic period to modern times, and it appears that the basic profile of modern western European mtDNA diversity was largely estab- lished by the Bronze Age. In this context, the well-documented narratives of the historic period seem to have played out on a background of European genetic diversity that was ultimately laid down thousands of years earlier."http://www.scirp.org/fileOperation/downLoad.aspx?path=AA20120100002_43394817.pdf&type=journal