There has been assumed that there prior to the rise of expansive civilizations (Sargon of Akkad) was much more linguistic and ethnic diversity than we currently see around us. Or, was evident even in the early Iron Age. In other words, the ancient Fertile Crescent may have resembled the highlands of Papua, with Hurrians, Akkadians, Gutians, Elamites, Sumerians, etc., all speaking mutually unintelligible dialects which diverged very far back in the mists of antiquity.
But there is a possibility that there was a great deal of demographic change between the Mesolithic and the Bronze Age, with successive waves of layering and replacement. According to another hypothesis a few groups of farmers may have expanded to swallow up thousands of hunter-gatherer groups. These homogeneous farmer societies eventually would diversify, because they were not united by the institutional forces which cemented later imperial regimes, in particular, literate elites which had a sense of consciousness which extended deep into the past because of written records. Therefore, the diversification would presumably have been similar to what we see with Romance languages, or Indo-Aryan, branching out from an common root language which replaced many competitors rapidly. Without writing and large scale polities the divergence would be more rapid, and there would be many more tips on the phylogenetic tree.
The problem with that model is that that Sumerians, and their neighbors the Elamites, as well as groups like the Hatti and Hurrians, none of these groups seem to be Indo-European or Semitic, the two dominant language families of Near East by ~ 1,000 BC. You have in the ancient Near East then a situation where the light of history reveals before us not the diversification of Indo-European and Semitic speaking farmers, but rather a host of unique and disparate peoples, all simultaneously lurching toward literate civilization, one after another.
Something just does not add up. Genetics will not solve the puzzle, but it may help in elucidating relationships. The origins of the Sumerians are murky, but many scholars have suggested that they may have arrived from the south (the oldest city, Eridu, is in the south). Others have suggested that the Sumerians descended from the mountains of the northeast. Though I presume that the people Arabia have changed a great deal since antiquity, it would be interesting if it was found that the Sumerians resembled the Qatari (at least the Eurasian component) more than they did the modern Assyrians.
Y-DNA Haplogroup J is a descendent of suprahaplogroup F, which encompasses a large group Y-DNA lineages (haplogroups F-T). Suprahaplogroup F is believed to have migrated from Africa approximately 50kya. Haplogroup J arose approximately 30kya (see Figure 4) and has been defined by a number of unique Y-chromosome polymorphisms; the 12f2a deletion and the M304 and P209 SNPs.
Haplogroup J-M172 is a Y-chromosome haplogroup which is a subclade (branch) of haplogroup J-P209. J-M172 can be classified as Mediterranean/Aegean (Di Giacomo, 2004), Greco-Anatolian, Mesopotamian and/or Caucasian and is linked to the earliest indigenous populations of Anatolia and the Aegean. It was carried by Bronze Age immigrants to Europe, and ultimately descends from the Cro-Magnon population (IJ-M429 Y-DNA) within the region spanning eastern Turkey and Persia around 35,000 years ago.
The origin of Y-DNA Haplogroup J maps to the Middle East around the ‘Fertile Crescent’, an area also known as the ‘Cradle of Civilization’ since this area saw the birth of many technological advancements that helped humans move from nomadic hunter-gatherers to an agriculture-based society living in one place. The sprouting of some the first cities and empires in human history were contingent on these developments and featured the proliferation of Haplogroup J.
The precise location for the origin of Haplogroup J is not known, but its prominence in the Near East/West Asia and the Middle East/Central Asia indicates that it likely arose in one of these regions. It is closely associated with the Fertile Crescent; an area spanning the Nile and Tigris/Euphrates River systems, with the Levant (present day Lebanon) in between.
Haplogroup J2 is thought to have appeared somewhere in the Middle East towards the end of the last glaciation, between 15,000 and 22,000 years ago. This region has encompassed many early cultures and empires from the Stone Age (Neolithic) to the Iron Age and has also been dubbed the ‘Cradle of Civilization’. Societies, dynasties and empires in this broad region include the Sumerian, Assyrian, Babylonian, Egyptian, Phoenician and Persian. Haplogroup J is also particularly abundant in Anatolia (present day Turkey) and the Y-chromosome diversity observed here suggests that this area is a possible source of this clade. Owing to these strategic locations, Y-DNA Haplogroup J is common on three continents: Asia, Europe and Africa.
Its present geographic distribution argue in favour of a Neolithic expansion from the Fertile Crescent. This expansion probably correlated with the diffusion of domesticated of cattle and goats (starting c. 8000-9000 BCE) from the Zagros mountains and northern Mesopotamia, rather than with the development of cereal agriculture in the Levant (which appears to be linked rather to haplogroups G2 and E1b1b).
A second expansion of J2 could have occured with the advent of metallurgy, notably copper working (from the Lower Danube valley, central Anatolia and northern Mesopotamia), and the rise of some of the oldest civilisations.
Quite a few ancient Mediterranean and Middle Eastern civilisations flourished in territories where J2 lineages were preponderant. This is the case of the Hattians, the Hurrians, the Etruscans, the Minoans, the Greeks, the Phoenicians (and their Carthaginian offshoot), the Israelites, and to a lower extent also the Romans, the Assyrians and the Persians. All the great seafaring civilisations from the middle Bronze Age to the Iron Age were dominated by J2 men. J2 (M172+) along with T (M70+) and G (M201+) are to be associated with Nahrain’s pre-Semitic civilizations (Sumer, Hurrians, etc…).
There is a distinct association of ancient J2 civilisations with bull worship. The oldest evidence of a cult of the bull can be traced back to Neolithic central Anatolia, notably at the sites of Çatalhöyük and Alaca Höyük. Bull depictions are omnipresent in Minoan frescos and ceramics in Crete. Bull-masked terracotta figurines and bull-horned stone altars have been found in Cyprus (dating back as far as the Neolithic, the first presumed expansion of J2 from West Asia). The Hattians, Sumerians, Babylonians, Canaaites, and Carthaginians all had bull deities (in contrast with Indo-European or East Asian religions).
The sacred bull of Hinduism, Nandi, present in all temples dedicated to Shiva or Parvati, does not have an Indo-European origin, but can be traced back to Indus Valley civilisation. Minoan Crete, Hittite Anatolia, the Levant, Bactria and the Indus Valley also shared a tradition of bull leaping, the ritual of dodging the charge of a bull. It survives today in the traditional bullfighting of Andalusia in Spain and Provence in France, two regions with a high percentage of J2 lineages.
Haplogroup J-M172 has been shown to have a more northern distribution in the Middle East, although it exists in significant amounts in the southern middle-east regions, a lesser amount of it was found when compared to its brother haplogroup, J-M267, which has a high frequency southerly distribution. It was believed that the source population of J-M172 originated from the Levant/Syria (Syrid-J-M172), and that its occurrence among modern populations of Europe, Central Asia, and South Asia was a sign of the neolithic agriculturalists. However, as stated it is now more likely to have originated in regions farther to the north, with the first metallurgists of the Middle East.
Anthropologist Carleton S. Coon is quoted as saying The Iraqi population is without doubt much the same today as it was in Sumerian, Akkadian, Assyrian and Babylonian times. The Iraqi people are a Caucasian people. It has been found that Y-DNA Haplogroup J2 originated in northern Iraq (Ancient Assyria).
In spite of the importance of this region, genetic studies on the Iraqi people are limited and generally restricted to analysis of classical markers due to Iraq’s modern political instability, although there have been several published studies displaying the genealogical connection between all Iraqi people and the neighbouring countries, regardless religious and linguistic barriers (Iraq contains Semitic peoples such as Arabs, Assyrians and Mandeans, Turkic peoples such as Turcomans,Indo-European peoples such as Kurds, Armenians, Shabaks and North Caucasian speakers such as Circassians). One such study reveals a close genetic relationship between all Iraqis, Kurds, Caspian Iranians and Svani Georgians.
Iraqi mitochondrial DNA (mtDNA) haplogroup distribution is similar to that of Iran, Syria, Israel, Palestine, Georgia, and Armenia, whereas it substantially differs from that observed in the Arabian Peninsula and North Africa. Iraqi Y-chromosome DNA (Y-DNA) haplogroup distribution is similar to that of Lebanon, Turkey, and Syria. No significant differences in Y-DNA variation were observed among Iraqi Arabs, Assyrians, or Mandeans.
For both mtDNA and Y-DNA variation, the large majority of the haplogroups observed in the Iraqi population (H, J, T, and U for the mtDNA, J2 and J1 for the Y-DNA) are those considered to have originated in Western Asia and to have later spread mainly in Western Eurasia. The Eurasian haplogroups R1b and R1a represent the second most frequent component of the Iraqi Y-chromosome gene pool, the latter suggests that the population movements from Central Asia/Eastern Europe into modern Iran also influenced Iraq to some degree.
Many historians and anthropologists provide strong circumstantial evidence to posit that Iraq’s Maʻdān people share very strong links to the ancient Sumerians, – the most ancient inhabitants of southern Iraq, and that Iraq’s Mandaeans and Assyrians share the strongest ethnic links to the Sumerians and Babylonians.
The Arabic speaking Beni Delphi (sons of Delphi) tribe of Iraq is believed to have Greek origins, from the Macedonian soldiers of Alexander the Great and the colonists of the Seleucid Empire.
The Assyrian Christian population are fairly closely related to other Iraqis, and also to modern Jordanians and some Near Eastern Jewish populations, yet due to religious and cultural endogamy have a very distinct genetic profile that distinguishes their population. “The Assyrians are a fairly homogeneous group of people, believed to originate from the land of old Assyria in northern Iraq [..] they are Christians and are bona fide descendants of their ancient namesakes.”
The relatively close genetic link with the indigenous Pre Arab Mesopotamian Assyrians and Mandeans indicates that many Iraqis who today speak Arabic are also to a great extent originally of Mesopotamian roots,as opposed to being ethnic Arabs.
In a 2011 study focusing on the genetics of the Maʻdān people of Iraq, researchers identified Y chromosome haplotypes shared by Marsh Arabs, Arabic speaking Iraqis, Assyrians and Mandeans “supporting a common indigenous local background.”
Studies have reported that most Irish and Britons are descendants of farmers who left modern day Iraq and Syria 10,000 years ago. Genetic researchers say they have found compelling evidence that four out of five (80% of) white Europeans can trace their roots to the Ancient Near East.
In another study, scientists analysed DNA from the 8,000 year-old remains of early farmers found at an ancient graveyard in Germany. They compared the genetic signatures to those of modern populations and found similarities with the DNA of people living in today’s South Eastern Turkey and Iraq.
Evidence of genetic stratification ascribable to the Sumerian development was provided by the Y-chromosome data where the J1 P58-branch reveals a local expansion, almost contemporary with the Sumerian City State period that characterized Southern Mesopotamia. On the other hand, a more ancient background shared with Northern Mesopotamia is revealed by the less represented Y-chromosome lineage J1-M267*.
Overall the results indicate that the introduction of water buffalo breeding and rice farming, most likely from the Indian sub-continent, only marginally affected the gene pool of autochthonous people of the region. Furthermore, a prevalent Middle Eastern ancestry of the modern population of the marshes of southern Iraq implies that if the Marsh Arabs are descendants of the ancient Sumerians, also the Sumerians were most likely autochthonous and not of Indian or South Asian ancestry.
Different from the Iraqi control sample, the Marsh Arab gene pool displays a very scarce input from the northern Middle East (Hgs J2-M172 and derivatives, G-M201 and E-M123), virtually lacks western Eurasian (Hgs R1-M17, R1-M412 and R1-L23) and sub-Saharan African (Hg E-M2) contributions.
Rather than “Sumerian”, it seems that the Marsh Arabs have rather preserved a more pristine Semitic patrilineal gene pool compared to the cosmopolitan Iraqi samples that have absorbed pre-Arab and pre-Semitic population elements.