A new article has appeared in Nature, Genetic origins of the Minoans and Mycenaeans, by Lazaridis et al. (2017), referenced by Science.
The origins of the Bronze Age Minoan and Mycenaean cultures have puzzled archaeologists for more than a century. We have assembled genome-wide data from 19 ancient individuals, including Minoans from Crete, Mycenaeans from mainland Greece, and their eastern neighbours from southwestern Anatolia. Here we show that Minoans and Mycenaeans were genetically similar, having at least three-quarters of their ancestry from the first Neolithic farmers of western Anatolia and the Aegean, and most of the remainder from ancient populations related to those of the Caucasus3 and Iran. However, the Mycenaeans differed from Minoans in deriving additional ancestry from an ultimate source related to the hunter–gatherers of eastern Europe and Siberia, introduced via a proximal source related to the inhabitants of either the Eurasian steppe or Armenia. Modern Greeks resemble the Mycenaeans, but with some additional dilution of the Early Neolithic ancestry. Our results support the idea of continuity but not isolation in the history of populations of the Aegean, before and after the time of its earliest civilizations.
Samples are scarce, and there is only one Y-DNA haplogroup of Mycenaeans, J2a1 (in Galatas Apatheia, ca. 1700-1200), which shows continuity of haplogroups from Minoan samples, so it does not clarify the potential demic diffusion of Proto-Greeks marked by R1b subclades.
Regarding admixture analyses, it is explicitly or implicitly (according to the press release) stated that:
- There is continuity between Mycenaeans and living people, so that the major components of the Greeks’ ancestry was in place already in the Bronze Age, after the migration of the earliest farmers from Anatolia.
- Anatolians may have been the source of “eastern” Caucasian ancestry in Mycenaeans, and maybe of early Indo-European languages (i.e. earlier than Proto-Greek) in the region.
- The “northern” steppe population (speaking a Late Indo-European dialect, then) had arrived only in mainland Greece, with a 13-18% admixture, by the time studied.
- Samples before the Final Neolithic (ca. 4100 BC) do not possess either type of ancestry, suggesting that the admixture detected occurred during the fourth to second millennium BC.
- Admixture from Levantine or African influence (i.e. Egyptian or Phoenician colonists) cannot be supported with admixture.
All in all, there is some new interesting information, and among them the possibility of obtaining ancient DNA from arid regions, which is promising for future developments in the field.
EDIT (20/8/2017): The article received widespread media attention, and two blog posts were linked to by the main author in his Twitter account: Who are you calling Mycenaean?, and On genetics and the Aegean Bronze Age. Apart from the obviously wrong reductio ad Hitlerum that pops up in any discussion on Indo-Europeans or genetics (even I do it regarding fans of admixture analysis), I don’t know why these created so much fuss (and hate) among geneticists. There seems to be a war brewing between Archaeology and Genetics.
Razib Khan writes The Revolution Which Came To Archaeology Without Archaeologists?, and I guess this is how many people feel in the field, but if they had studied some minimal archaeology of the samples they are studying they would know that their conclusions would come as no surprise, in any case. They can solve old archaeological questions, and they can help create new hypothesis. That’s it. Regarding the study Mr. Khan believes did come as a surprise to archaeologists, that on Bell Beakers, I would like to remind him of the predictions Volker Heyd did about genetics already in 2007, based only on Archaeology.
Featured map: samples studied, from the article.