A PROPOSED SECOND AVENUE FOR THE INTRODCTION OF STEPPE ANCESTRY INTO SOUTH- WESTERN EUROPE.

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M. Sally McGrath [email protected].

Studies of ancient DNA and the use of Strontium Isotope Analyses (SIA) have become proxy for the absence of written records for European Pre-History. A comparison between the DNA signatures of modern European populations and that of ancient populations has allowed broad stroked insights into the movements of different populations in Eurasia. As more ancient DNA is sequenced, a more detailed picture will be revealed, but the impetus for such movements and the role of individual agency still needs investigation. The use of SIA however is only significant for identifying first generation migrants.

Furthermore, the similarities of some geological formations across Europe creates uncertainty in pinpointing the original homelands of migrants. Therefore, this technology can only signify an origin outside of the final resting place of ancient individuals.

The present state of research suggests a one-time massive influx of steppe individuals off the

Eurasian steppe region north of the Black Sea into Western Europe at the beginning of the Bronze Age

(Haak et al, 2015). Here, I intend to investigate a second possible avenue for the introduction of steppe ancestry into southern Europe. The y haplogroups R1a and R1b, have been associated with this massive one-time influx of steppe individuals. Today, these form the most common lineages in

Western European. In Haak et al, 2015 study, 7 Yamnaya males belonged to R1b, subclade M269 and one hunter-gatherer from the Samara regions also displayed R1b but not the M269 subclade. These steppe migrants also carried traces of genetic material similar to that found in the Caucasus and South

Asia (Caucasus Hunter Gatherers and Eastern Hunter-gatherers) which is absent in an early wave of

Anatolian Neolithic farmers migrants. The population of Europe prior to this second migration was a mixture of Neolithic (Anatolian) farmers and Western Hunter Gatherers.

Today, again according to Haak et al,2015, Spanish and Sardinian populations display 75% or more of the Neolithic farmer genes and ancient samples from pre-Bronze Age Spanish individuals

1 revealed only one individual with R1b steppe ancestry. There is however a problem with the relative smallness of the number of samples and the absence of studies in some geographical regions. The present state of knowledge suggests a steady decline in steppe ancestry from east to west across mainland Western Europe with the smallest proportion of steppe ancestry in the south-west. Such a descending scale is not evident however in all present day Atlantic coastal populations. Contrary to this perception, the R1b-M269 and its subgroups actually demonstrate a different scale ranging from

41% in Germany to 83% in Ireland and similar high occurrence among the Basque (Sole-Morata et al,

2017; Cassidy et al, 2016). The continued presence today of the non-Indo-European Basque language among a population with high steppe R1b-M269 haplogroup ancestry is an anomaly given that steppe ancestry is supposedly associated with the introduction of the Indo-European language group. This raises the possibility of another avenue for the introduction of this steppe ancestry. One note of caution however, when examining modern population it must be kept in mind that east to west movements of people continued down through the Iron Age and the 1st millennium AD.

Martiniano et al,2017 suggest the finds of three Iberian Bronze Age males carrying the R1b haplogroup was the result of small-scale migration in contrast to that seen in central and northern

Europe. The authors furthermore suggest that this occurrence of steppe ancestry in Portugal is related to the emergence of the Bell Beaker phenomenon in southwestern Iberia. The people who transported this set of material culture established wide ranging networks that could have facilitated a back- migration to Iberia.

The Bronze age (2500-1000BC) is a period of unprecedented interconnectedness with the movement of both groups of males and whole families as demonstrated by SIA. This is the period in southern Europe which is preceded by the Bell Beaker phenomenon.

2 This phenomenon relates to a group of material remains, mainly found in mortuary contexts.

These remains include; a distinctive beaker pot; wrist guards associated with archery; arrows; daggers made from flint, obsidian or copper/bronze and a change from group burials to single cist burials. It must be noted that not all these items are found in every Beaker burial but in general there was present a beaker type vessel. The earliest confirmed C14 dating of Beaker pottery comes from the

Tagus estuary on the Atlantic Iberian coast and is dated 2750 BC (Olaide et al, 2018). Sometime later this material horizon appears around the Rhine delta in association with Corded Ware material (Price,

Knipper, Grupe & Smrcka, 2004). This second appearance of Bell Beaker material has, according to radiocarbon dating, been assigned a date shortly before 2500 BC (Lanting and van der Waals, 1976). It is theorized that the Rhine delta Bell Beakers individuals introduced this set of material culture to eastern England and Scotland (Case, 2001). It was Gordon Childe in the early 1920’s who first suggested that these Bell Beaker remains were associated with copper exploitation. He interpreted the widespread occurrence of this phenomenon to a small-scale movement of individuals searching for gold, copper and other desirable scarce resources.

Initially, the early Bell Beaker period over-laps the use of Megalithic monuments associated with collected burials. These monuments and their locations argue for a pan-European belief system, with ceremonial centres attracting people from a distance. The location of these centres suggests that groups of individuals travelled over long distances and specifically by water. While single cist burials are associated with the steppe migration, in the Atlantic region group burials in association with Bell

Beaker materials were common (Fitzpatrick, 2015), as too the use or re-use of dolmens (Vazquez Liz,

Nonat & Martinez, 2015).

Around the Mediterranean, dolmens, another form of megaliths, are found in Sardinia, southern Italy, Malta, North Africa and as far east as Naxos in the Aegean and Mani in southern

3 Peloponnese (Moutsopoulos & Dimitrokallis, 1977; 1976). An association between Bell Beaker individuals and the builders of these dolmens is possible. Furthermore, such journeys could have facilitated interaction between the adventurers and existing populations with an exchange of knowledge about regions at a distance. The appearance of copper daggers in the Aegean which according to the German scholar Schuhmacher (2004) occurred 300 years earlier in Iberia, could be evidence of such contacts.

When finds of Bell Beaker remains are placed on a map, it demonstrates just how widespread this phenomenon was and how it could have been related to water transport. Using an analogy from

the Roman period where water transport of goods used both sea-lanes and European rivers for north to south, and east to west movement, it is possible the transmission of the Bell Beaker phenomenon followed a similar pattern.

Evidence for a genetic alignment with Iberian populations is found in some middle European

Bell Beaker individuals from Mittelelbe-Saale, Germany (Brotherton et al,2013). In general, however it has not been proven that a single group was responsible for the spread of this cultural horizon.

Individuals found in Bell Beaker type cemeteries located on river terraces in Central Europe were examined using SIA. On average these cemeteries contained the remains of four generations with a high proportion of both males and females of non-local origin. These sites date between 2500-2150 BC.

In a more recent study of DNA from Bell Beaker associated individuals from a variety of sites, Olaide et al, 2018 determined that those from Iberia revealed a higher percentage of Neolithic genes. These

Iberian Bell Beaker individuals were found to carry three main genetic components; European Hunter-

Gatherers; Neolithic genes from Anatolia and the Levant; and Neolithic individuals from Iran. The last group is also present in an admixed form in steppe populations. Steppe ancestry is usually modelled as a mixture of Eastern Hunter Gatherers, Caucasus hunter-gatherers and farmers from northern Iran

4 (Mathieson et al, 2018). Outside of Iberia and Sicily, all other Bell Beaker associated individuals tested carried a higher degree of steppe ancestry.

When Gunther et al, 2015 sequenced the DNA from eight individuals excavated from a cave in north central Spain and dated between 5500-3500 BP they found that all 8 individuals (4 males and 4 females) carried mt DNA associated with early farmers and hunter gatherers. When comparisons of these results were made with modern day Europeans, it was found that all modern-day Iberians have varying degrees of ancestry from four groups: early farmers, hunter-gatherers, North African and

Caucasus/Central Asia which indicates an influx of genes sometime after the end of the Neolithic.

Olalde et al, 2019 examined a larger sample of DNA from ancient Iberian Peninsula individuals and suggested that steppe ancestry while arriving in the last two centuries of the 3rd millennium BC only started to admix with local Iberians after 2000 BC. It is at this point that the R1b-M269 haplogroup enters with an influx of males only.

The evidence presented above suggests that there may have been two avenues for the arrival of steppe ancestry in western Europe. Just as Shennan (2018) showed that Anatolian Neolithic farmers entered Europe by two routes so too is it possible that individuals carrying steppe ancestry entered

Western Europe by the same two different routes. One difference however is in the motivation behind these two different trajectories.

The Bronze Age takes its name from the use of copper alloyed with tin that was used to make high status items. Copper itself was also used to make tools and weapons. On the Iberian Peninsula there is widespread evidence for the local extraction and use of copper during the 3rd millennium BC

(Cortizas et al, 2016). In fact, the Tagus delta with the earliest evidence of the Bell Beaker phenomenon was a centre for smelting and distribution of copper. The Irish Bronze Age individuals associated with

5 Beaker material were also associated with copper mining and smelting. Copper and tin ores are however only found and exploited in certain regions of Eurasia.

In the more advanced societies of the Middle East there was a great demand for copper and tin but no ready source. Initially, in the 3rd millennium BC copper and tin was supplied to the

Mesopotamian cities from the north east. The copper appears to have come from the Samara steppe region, north of the Caspian Sea. Here, the DNA analysis from ancient individuals (5200-4000 BC) reveals an ancestry that is a mixture of Eastern Hunter Gatherers and Caucasus Hunter-gatherers with

Iranian farmers (Wang et al, 2018). This same region is the homeland of the Yamnaya who introduced steppe ancestry into Northern Europe. Here copper was easily extracted from sandstone but there is only evidence of small-scale smelting in nearby communities, which suggests that most of the copper was exported un-processed. Mining using a burn process, continued over 500 years, but so great an amount was extracted that wood supplies became exhausted and copper supplies dwindled with settlements abandoned by 1400 BC (Diaz Del Rio et al, 2006). Evidence for actual smelting and metalwork occurs further south in the Caucasus regions of Armenia and Georgia (Tedesco, 2006).

The east to west trade route across northern Mesopotamia would appear to be connected with the Hurrians, a people who arrive from the east off the Iranian plateau sometime in the 3rd millennium

BC. That they knew horses and donkeys and perhaps used them is attested to by the numerous three- dimensional clay statues found in their centres (Hauser, 1998; Ivanov, 1998).

By the mid 2nd millennium new sources of copper were required, especially for weapons needed by competing Mesopotamian, Levantine and Egyptian kingdoms. Tin was also required to produce bronze and initially it too was sourced further east either in Afghanistan or in the Pamirs mountain range (Kohl & Lyonnet, 2008) but as the supply chain for copper was disrupted, so too was the supply of eastern tin. Recent isotope examination of tin ingots from Israel point to Cornish mines as

6 the source of tin in the second half of the 2nd millennium BC (Berger et al, 2019). While by the mid 2nd millennium BC, Cyprus became a source of copper as evidenced from the Hittite records. Finds of Kura-

Araxes related hearth stands on Cyprus suggests the presence of migrants from the Caucasus region

(Frankel, 2000).

Ores must have moved in the company of traders and smiths who, when they died were buried in places far from their original homes. Often then evidence of metal working comes from the mortuary deposits. These include not only large quantities of metal objects, but also metalworking tools and moulds. The Amesbury Archer, radiocarbon dated 2895+/-32 BC, was found buried not only with weapons but also stone metalworking tools. SIA of his remains revealed that he originated from the Alpine region but may have moved several times before arriving in south eastern England

(Fitzpatrick, 2015). Buried in a collective grave nearby were five males. Radiocarbon dating indicated they had died at different times. SIA of three of these individuals indicated they had moved twice as young individuals and originated from a location characterized by Pre-Cambrian rocks. Possible locations could be Wales, Brittany, Portugal, Massif Central (France) and the Black Forest. The first of these men died sometime between 2500 – 2350 BC. Therefore, they arrived in England prior to the appearance of Bell Beaker materials on the Rhine Delta. SIA of human remains buried on the Isle of

Thanet in the Thames estuary reveal the presence of both individuals from Scandinavia and from the

Western Mediterranean (McKinley et al, 2013). While on the Maltese archipelago at the megalithic temple of Tarxien several burials circa 2000-1500 BC, contain numerous daggers, axes, awls and lumps of copper (Tanasi, Tykot, Hassam & Vianello, 2019). The daggers and axes show similarities to Sicilian ones. As there is no evidence for the mining of copper in Sicily prior to the late Bronze Age, the smelting and production as attested to by the presence of moulds there, must have used copper from off island.

7 It is possible that small groups of primarily men, fanned out in search of extractable ores that they either worked on site or transported to other locations where smelting occurred. Extractable ores were found in Anatolia, eastern and western Northern Italy, and of course in Iberia and on the western

Atlantic seaboard. It may be no accident that non-Indo-European languages were still in use in some of these regions down to the Roman period (Anthony & Ringe, 2015). When individuals or groups of single men settle in a new location, they seek relationships with indigenous women who raise the offspring and pass on their own language. In this way indigenous languages persist.1

It is now possible, using lead isotope analysis (LIA) to chart the circulation of ores. Cypriot copper smelting started in the late 3rd millennium BC, a date earlier than indicated from Hittite records.

In addition, there is evidence on Cyprus of the use of foreign copper sourced from a wide variety of regions. These include Sardinia and the Central Massif, France (Stos-Gale & Gale, 2010). Analysis of

Cypriote bronzes items suggest a tin source in Southern France or further west.

New evidence from an examination of lead isotopes in copper and bronze items from Denmark suggests that copper in use there could have originated from the Great Orme mine on the northern coast of Wales, and also from eastern Italian Alps and Iberia (Melheim et al.2018). However, just as SIA can only determine non-local identity, LIA only shows from where copper did not originate.

Both ancient Minoan and Mycenaeans derive ancestry from Anatolian farmers, but they also carry a lesser degree of ancestry from Caucasus/Iran sources (Lazaridis et al, 2016). This latter ancestry is associated with steppe ancestry but the evidence from Crete suggests this arrived separately and without Eastern Hunter-gatherer ancestry. DNA analysis did not reveal the presence of the R1b haplogroup, but it did reveal another y haplogroup associated with Caucasus Hunter-gatherers. There

1 Personal conversation with C. Runnels at the 2012 AIA annual meeting concerning the continuation of the Greek language after the Frankish invasion. 8 was no ore mining on Crete, but the presence of ox-hide ingots indicates that the island was involved in the metal trade (Liard, 2010; Soles, 2004). Furthermore, the large piles of swords2 found as votive items at peak sanctuaries argues for the presence of sword workshops at the various centres on the island.

On Sicily, 3 out of 5 Bronze Age DNA samples carried the R1b-M269 haplogroup. Fernandes et al,2020 suggests this steppe ancestry was introduced from Iberia. Interestingly, Iranian related ancestry is detected in Sicily and appears to have arrived there by the Middle Bronze Age but did not spread to Sardinia or the Balearic Islands. Modern southern Italians along with Sicilians carry a

Levantine and Caucasus related ancestral component which their share with the populations of the

Greek islands and Cyprus (Sarno et al. 2017). It is theorized that this form of ancestry reached Sicily and southern Italy prior to Greek colonization.

Sardinia was a source of copper and Levantine and eastern ancestry has been detected there in two individuals dated 2345-2146 BC. A female associated with Beaker remains from the Balearic

Islands dated 2400 BC revealed ancestry related to steppe-Samara. Two later individuals from the

Balearic Islands also revealed steppe ancestry but to a lesser degree so indicating admix. Today the R1b y chromosome is common in the Balearic population.

Archaeological evidence of contact between Sardinia and southern Iberia is attested to by the discovery of an El Argar sword on the island (Balmuth, 1986). While in the El Argar region archaeological evidence shows intensification of contacts with the eastern Mediterranean from the early 2nd millennium BC.

2 On display at the Heraklion Museum. 9 When considering personal agency, the individual males who transmitted steppe ancestry around the Mediterranean must be considered a ‘special’ group. They were risk takers who for whatever reason had left their original home to seek new opportunities. They may have possessed special skills such as smiths or the ability to conduct trade. SIA studies suggest they shared a willingness to move, not once but perhaps several times and assimilate into foreign communities (Desideri et al,

2010; Fitzpatrick, 2015). The motivation for such movements must presumably have been economic.

For Levantine travellers to set out westward, there must have been prior knowledge of the possible advantages to be gained, and furthermore knowledge of which routes to follow. The transmission of such knowledge might have been the role played by the Bell Beaker people.

Conclusion:

Working with copper, tin and gold are individual acts. Mortuary evidence suggests this was gender specific to males. Skills associated with metal working must be practiced repeatedly which suggests that the transfer of this technology was probably not by diffusion but by the mobility of specific individuals who had learnt this skill within the confines of a close group, ie a family and had the opportunity to practice it regularly.

Allentoft et al,2015 demonstrated that Caucasus ancestry was actually steppe ancestry and not derived from the Southern Caucasus. Conformation of this comes from Iranian archaeologists who have shown that the Caucasus region was more porous that previously thought (Iravani Ghadim &

Eeikzadeh, 2018) with both north to south and south to north movements. Therefore, given the need to find new sources of copper and tin in the 2nd millennium BC, it is possible that individuals carrying steppe ancestry moved westward, island hoping across the Mediterranean. They may have been prospectors and traders, as well as metal smiths. Ore bodies in Cyprus, Sardinia and further west in

Iberia, France and England would have offered new opportunities. Steppe ancestry first arrives in Iberia

10 prior to 2000 BC. While in both Sardinia and Sicily contact with Bell Beaker associated individuals is evident prior to this date. A dependence on sea voyages and the early dates in associated with Bell

Beaker remains strongly suggests that this set of material remains was associated with travellers who interacted in the lands bordering the eastern end of the Mediterranean with individuals carrying steppe ancestry. These travellers would have disseminated knowledge of distant lands and in so doing spurred adventurous individuals to sail west. In this manner a second stream of steppe ancestry was introduced to southern European populations on the peripheral of the European landmass.

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