The Italian Peninsula through Ancient DNA

[R.Rocca]

This topic is all over the place, so I thought I would collect the relevant abstracts of papers to-be published here:

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Steppe and Iranian ancestry among Bronze Age Central and Western Mediterranean populations - Ron Pinhasi, Daniel Fernandes, David Reich

ABSTRACT: Steppe-related ancestry is known to have reached central Europe ca. 3000 BCE, while Iran-related ancestry reached Greece by 1500 BCE. However, the time course and extent of their spread into the central/western Mediterranean remains a mystery. We analysed 48 Neolithic and Bronze Age individuals from Sicily, Sardinia and the Balearic Islands aiming to investigate when and how continental European and Aegean influences affected these insular populations. Results show that the first Balearic settlers had substantial Steppe-related ancestry which was subsequently diluted by increasing proportions of farmer-related ancestry. In Sardinia, we identified the appearance of Iran-related ancestry from the Aegean as early as the Middle Bronze Age, with no genetic influences seen from populations carrying Steppe-related ancestry despite cultural or commercial exchanges with Bell Beaker populations. In Sicily, during the Bronze Age and possibly earlier, we found evidence for admixture with groups carrying both these ancestries. These results suggest that Steppe-related migrants had a crucial role in the settlement of the Balearic Islands and their ancestry reached as far south as Sicily, and that the population movements that brought Iran-related ancestry to the Aegean also impacted the Western Mediterranean around the same time the first civilizations started to develop.

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A 12,000-year Genetic History of Rome and the Italian Peninsula - Hannah Moots

Ancient DNA has become a powerful tool for studying the human past. This talk highlights our team’s multidisciplinary approach to analyzing new genomic evidence from Rome and the Italian Peninsula in the context of the extensive archaeological and historical record of the region. We have built a time series of 134 ancient genomes that spans the last 12,000 years, from the Upper Paleolithic to the present, allowing us to present a contextually-situated discussion of genomic changes through time. This approach allows us to study changes ranging from individual traits of interest, such as lactase persistence, to broad population-level shifts. We see evidence that as Rome grew from a small city to an empire encompassing the entirety of the Mediterranean - or Mare Nostrum, ‘our sea’, as the Romans called it - and beyond, the city of Rome became a mosaic of inhabitants from across the empire and remained so even after the fragmentation of the Western Roman Empire. I will illustrate these general trends with case studies, such as paleogenomic data from Isola Sacra, the necropolis for the port towns of Ostia and Portus, in which contextualizing archaeological and textual evidence have been instrumental in understanding the genetic structure of the Roman population in our study.

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Investigating Sardinian population history with ancient DNA - J.H. Marcus

The sequencing of ancient DNA (aDNA) has provided new understanding into human movement and demography for many regions around the globe. For mainland Europe, ancient DNA studies have revealed a dynamic history, with major inferred population influxes due to Neolithic and Bronze Age expansions. The population of the Mediterranean island of Sardinia has been notable in these studies–typically aDNA samples of the early Neolithic on mainland Europe cluster with modern Sardinian samples. The standing model is that Sardinia had a high influx of Neolithic ancestry followed by relative isolation from the mainland and subsequent Bronze Age expansions. To gain further insight, we analyze genome-wide capture data (~1.2 millions SNPs) of 26 ancient Sardinians spanning the Neolithic, Copper Age, and Bronze Age, including individuals from Sardinia's Nuragic culture. Merging this novel data with 998 previously studied aDNA samples from across Europe and throughout the last ten millennia, we are able to place the ancient Sardinian samples into the broader context of the peopling of Europe. We confirm that ancient Sardinian samples show a strong affinity to early Neolithic samples and a near complete absence of the “Steppe” ancestry associated with Bronze Age expansions on the mainland. Interestingly, we also detect elevated affinities with pre-Neolithic peoples of Europe. Moreover, we studied genetic change through time within Sardinia. To this end, we analyzed whole-genome sequence data from approximately 1,500 modern Sardinian individuals, densely sampled across much of the island. Using our ancient samples enables us to detect significant signs of recent admixture, in particular with a strong influence from the Mediterranean region. We also find that populations from the more isolated mountainous provinces of Sardinia are less admixed and have experienced high levels of genetic drift. Overall, our analysis allows us to shed new light on the intriguing history of the peopling of Sardinia.

[R.Rocca]

And Ryukendo first hand summary of the Moots presentation:

Presentation by Hannah Moots. No pictures, not allowed. Paper coming out in a couple of months, done with Pinhasi and Pritchard.
134 genomes, spanning 12000s BP to Renaissance and enlightenment. 0.5-3.5X coverage. Vast majority of sampling sites concentrated in Rome and surrounds, lowlands of Latium around the Tiber River, up to Ostia, almost all restricted to Lazio. Some extend to Abruzzo, South Le Marche, none, or maybe one, in Tuscany, and on the South of Tuscany if that. Couple of samples from Sardinia. I'll give a PCA position and a ADMIXTURE description for each time period. Note that the ADMIXTURE only had Iranian, EEF, WHG, EHG and Levant_N, no CHG. Where Iran N appears, it may be a stand-in for CHG. There is something quite puzzling in the list below, mislabeling in the slides? But that doesn't explain it either.

UPPER PALEOLITHIC
All WHG

NEOLITHIC
Mostly EEF, some WHG. Some Iran_N, quite a significant quantity, as much as WHG. PCA position Between Sardinia and Maltese, east of Sardinia, closer to Sardinia than to Maltese. Very homogeneous.

BRONZE AGE (EARLY)
Overlaps modern-day Sardinia, Iran_N percentage declines, WHG and EEF increases
(Note that this represents a Europeanisation of the gene pool!) Very homogeneous.

IRON AGE TO REPUBLICAN PERIOD (700-20BC)
Note: Separated from previous period by 1000 year gap.
Fewer samples, of those that exist 60% overlap with North Italy, 40% overlap with South Italy and Sicily, centroid of overall cluster in central Italy but no samples occur there, very wide spread.
EHG appears, Levant N Appears for the first time, sporadic and inhomogeneous distribution, Iran_N increases further.

IMPERIAL PERIOD
Dense cluster centroid between Greeks, Cypriots, South Italians/Sicilians, and Syrians, closest to Sicilians. Long tail stretching from central cluster to Syrians and Iraqi Jews. Couple of Northern-shifted samples overlapping N Italy, France, Spain.
Iran_N increases further, Levant N again sporadic and inhomogeneous.

LATE ANTIQUITY
Tight cluster centroid in S Italy, in the same place as in the previous period. Southern tail to Middle East disappears. N Italian, Northern European and NW European outliers exist.

AFTER
Resemble modern central Italians.

Lactase persistence alleles appear abruptly after 0 AD.

Heterozygosity reaches modern level after Iron Age.

No information given on uniparentals.
Isotope information not available yet, no way apart from archaeological context to tell between migrants and locals.

Represents a preliminary effort, more work coming later.

[Nino90]

A short question. How big impact did the Germanic and Vandal invaders have in late antique? And early Medieval times?

[R.Rocca]

And these blurbs from already published papers:

The Demographic Development of the First Farmers in Anatolia - Kılınc et al. 2016

We next used our data to investigate a more recent case of possible regional migration. Previous work [6] had noted genetic affinity between Kumtepe from northwest Anatolia and the Tyrolean Iceman [23] from northern Italy. We found that the three Remedello individuals from Chalcolithic northern Italy [24], largely contemporary and possibly genetically and culturally affiliated with the Iceman, also had high affinity to Kumtepe in D statistics (Figure 3B; Data S3). A similar tendency for Kumtepe allele sharing was seen for a Chalcolithic individual from Hungary, CO1 [7], but was non-significant (Figure S3E; Data S3). Intriguingly, the Iceman/Remedello group was more similar to Kumtepe than to Boncuklu, Barcın, Tepecik-C¸ iftlik, or European Neolithic individuals. We further found that both Kumtepe and the Iceman/Remedello group carried more CHG alleles than other Neolithic populations (Figure 3C). This pattern of additional CHG allele sharing simultaneously observed in Iceman/Remedello and in Kumtepe is not mirrored in convergent allele sharing with other European hunter-gatherers (Figures S3F and S3G). We also found that Tepecik-C¸ iftlik individuals were consistently closer to Iceman/Remedello and to Kumtepe than to any other Anatolian or European early Neolithic population, including their contemporary Barcın and the neighboring Boncuklu (Figure 3D). These results point to gene flow from an eastern source into Chalcolithic Kumtepe and later into Europe, which could have crossed central Anatolia already before the Chalcolithic.

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The Beaker phenomenon and the genomic transformation of northwest Europe - Olalde et al 2018

From the pre-print and final published versions:

Population discontinuity in northern Italy:
Our Beaker Complex individual from Parma is slightly shifted towards populations with steppe ancestry in the PCA (Fig 1b). We tested for symmetry between BB_Italy_Par and Remedello_CA3 (Table S2), a culture preceding the Beaker Complex in northern Italy. Several steppe-like populations such as EHG (Z=4.6) or Yamnaya_Samara (Z=3.9) share more alleles with BB_Italy_Par than with Remedello_CA, indicating that our Italian Beaker Complex individual harbors a steppe-related ancestry component not present in the previous Remedello culture.

Ancestry heterogeneity in Via Guidorossi (Parma, northern Italy):
Two Beaker-associated individuals from Parma (BK_Italy_Gui2 and BK_Italy_Gui3) are slightly shifted towards populations with steppe ancestry in the PCA (Fig 1c), while the remaining individual (BK_Italy_Gui1) is not. We tested for symmetry between BK_Italy_Gui1 and both BK_Italy_Gui2 and BK_Italy_Gui3 (Table S2). Neolithic and Copper Age European populations share more alleles with BK_Italy_Gui1 than with BK_Italy_Gui2 or BK_Italy_Gui3. Furthermore, Steppe populations share more alleles with BK_Italy_Gui3 than with BK_Italy_Gui1, showing that individuals from this site did not form a genetically homogeneous group. This is especially interesting since BK_Italy_Gui1 (a woman) and BK_Italy_Gui3 (a man) were buried together in the
same tomb.

We find that in areas outside of Iberia, with the exception of Sicily, a large majority of the Beaker complex-associated individuals that we sampled derive a considerable portion of their ancestry from steppe populations (Fig. 2a).

[LTG]

A short question. How big impact did the Germanic and Vandal invaders have in late antique? And early Medieval times?

We know that during Late Antiquity the Romans all densely clustered with South Italians. After this, they all appear to densely cluster with Central Italians. This would indicate that the northern invasions had quite a significant impact.

[Cascio]

I can't see how they could have a significant impact because Rome and its immediate vicinity were never conquered or settled by the Langobards, the most important Germanic settlers of early medieval Italy.

[LTG]

I can't see how they could have a significant impact because Rome and its immediate vicinity were never conquered or settled by the Langobards, the most important Germanic settlers of early medieval Italy.

An alternative theory would be if a more North Italian population remained isolated in the north for most of the Imperial Period and Antiquity, before eventually migrating down the peninsula at the beginning of the Medieval Period. If mixing between a North Italian and South Italian type population occurred on a large scale, the next generation would logically cluster like that of Central Italians.

LATE ANTIQUITY
"Tight cluster centroid in S Italy, in the same place as in the previous period. Southern tail to Middle East disappears. N Italian, Northern European and NW European outliers exist".

[Erikl86]

First of all, this study:

"Steppe and Iranian ancestry among Bronze Age Central and Western Mediterranean populations

Iran-related ancestry reached Greece by 1500 BCE. However, the time course and extent of their spread into the central/western Mediterranean remains a mystery. "

Is verified by the Moots presentation as described by Ryukendo:

NEOLITHICMostly EEF, some WHG. Some Iran_N, quite a significant quantity, as much as WHG. PCA position Between Sardinia and Maltese, east of Sardinia, closer to Sardinia than to Maltese. Very homogeneous.


BRONZE AGE (EARLY)
Overlaps modern-day Sardinia, Iran_N percentage declines, WHG and EEF increases
(Note that this represents a Europeanisation of the gene pool!) Very homogeneous.

While by EBA the Iran_N percentage declines, it's still there.


Now, as for the enigma of what exactly North-shifted Central Italians from Sicilian/Aegean-like in Late Antiquity to modern day Central Italians after that, it is tempting to believe these are the Germanic tribes such as the Goths and Lombards.

BUT, now one has another problem... since there appears to be a genetic continuity (of a sort) in Northern Italy, from the Bell Beaker samples through the Collegno samples and all the way to contemporary North Italians, PLUS now we know that pre-IA Central Italians were similar to North Italian BB (EEF, WHG and some Iran_N/CHG-like) and that even after the Aegean-shift began in the IA around ~60% of the Central Italian samples were North Italian-like, it seems rather unlikely that any North-shifting geneflow would just skip North Italians and affect ONLY central Italians after Late Antiquity. So by that logic, there shouldn't be any genetic continuity for Northern Italians, and they should all plot much Northern that what they do (unless the Aegean-shifting event spread all the way to North Italy, which I doubt, and then indeed a Germanic influx after Late Antiquity North-shifted Northern Italians back to where they are today).

Now since the Aegean/Sicilian cluster of Imperial Romans seems to give credibility to the Roman ethnogenesis myth of them descending from Greeks (Trojans), all bets are off. My bet? After the Gothic War in the 6th century, when the East Roman Empire recaptured the Italian peninsula, there have been substantial destruction in most urban centers in the Italian peninsula. 5 years after Justinian died, the Lombards occupied most of Italy but the Southern tip (Calabria, Puglia and Sicily). Perhaps they've encouraged the relatively less affected Northern regions to resettle in the rest of Italy, thus bringing Northern Italians to resettle in Central Italy. At the same time, the Southern parts of the Italian peninsula, still under Byzantine rule, was resettled by Hellenic people from the rest of the Byzantine Empire.

It's just a theory, but I'm open now to pretty much anything after this new findings.

[Sikeliot]

First of all, this study:



Is verified by the Moots presentation as described by Ryukendo:



While by EBA the Iran_N percentage declines, it's still there.


Now, as for the enigma of what exactly North-shifted Central Italians from Sicilian/Aegean-like in Late Antiquity to modern day Central Italians after that, it is tempting to believe these are the Germanic tribes such as the Goths and Lombards.

BUT, now one has another problem... since there appears to be a genetic continuity (of a sort) in Northern Italy, from the Bell Beaker samples through the Collegno samples and all the way to contemporary North Italians, PLUS now we know that pre-IA Central Italians were similar to North Italian BB (EEF, WHG and some Iran_N/CHG-like) and that even after the Aegean-shift began in the IA around ~60% of the Central Italian samples were North Italian-like, it seems rather unlikely that any North-shifting geneflow would just skip North Italians and affect ONLY central Italians after Late Antiquity. So by that logic, there shouldn't be any genetic continuity for Northern Italians, and they should all plot much Northern that what they do (unless the Aegean-shifting event spread all the way to North Italy, which I doubt, and then indeed a Germanic influx after Late Antiquity North-shifted Northern Italians back to where they are today).

Now since the Aegean/Sicilian cluster of Imperial Romans seems to give credibility to the Roman ethnogenesis myth of them descending from Greeks (Trojans), all bets are off. My bet? After the Gothic War in the 6th century, when the East Roman Empire recaptured the Italian peninsula, there have been substantial destruction in most urban centers in the Italian peninsula. 5 years after Justinian died, the Lombards occupied most of Italy but the Southern tip (Calabria, Puglia and Sicily). Perhaps they've encouraged the relatively less affected Northern regions to resettle in the rest of Italy, thus bringing Northern Italians to resettle in Central Italy. At the same time, the Southern parts of the Italian peninsula, still under Byzantine rule, was resettled by Hellenic people from the rest of the Byzantine Empire.

It's just a theory, but I'm open now to pretty much anything after this new findings.

I think that if we view South Italians and Aegean islanders as the "base" then we can see a gradient as you move north in Italy caused by Germanic influence, and a gradient throughout Greece caused by Slavic ancestry.

I think there was Germanic and Slavic input in Sicily/Aegean/Calabria/etc. but that the Levantine influence shifted them back south, and that's how we can reconcile everything.

[Camulogène Rix]

As Latin is an Indo-European language and as there is no language without original speakers, it is useful to read this short text from Mallory (Encyclopaedia of IE culture) to put things into perspective from both linguistic and archaeological points of view.
Sorry, no DNA consideration here but pluridisciplinary approach is often necessary to get the big picture. I hope that the release of Iron Age uniparental haplogroups will give us some clues on this puzzle.

One of the most popular of the traditional models for IE -migrations into Italy has been sometimes dismissed as pigoriniana, a term coined after its major proponent.
L.Pigorini suggested that the Italic-speaking peoples came across the Alps during the Bronze Age and introduced the Terramare culture (c 1500-1100 BC) in northern Italy. This model was consciously an extension of the historically attested movement of Celtic peoples in the Iron Age who also penetrated (and pillaged) Italy from the north. This model sees the IndoEuropeanization of the peninsula essentially in terms of a north to south movement. While there is no question that northern Italy was in close contact with developments north of the Alps, the spread of bronze metalworking traditions from the north or indeed across Europe need not be explained in terms of the movement of an ethno-linguistic group. Moreover, the
pattern of language distributions in Italy, especially with non IE Etruscan lying athwart central Italy, renders a simple north south movement of language and people an unconvincing explanation for all the IE languages of the peninsula, unless linked to the evidence for other movements as well.

Later migrations from the north are proposed in the formation of both the Proto-Villanovan and Villanovan horizons. These horizons see the widespread distribution of bronze artifacts of general central European types coupled with the expansion of cremation cemeteries clearly associated with the Urnfield phenomenon north of the Alps. The problem with seeing these cultural horizons as reflections of IE immigrations down the Italian peninsula is the fact that both the Proto-Villanovan (1100-900 BC) and Villanovan (c 900- 500 BC) cultures clearly coincide with the distribution of the historical Etruscans as well as the IE Italic groups (hence some
would still argue that the Etruscan represents a late intrusion into Etruria, perhaps coincident with the spread of east Mediterranean artistic styles). On the other hand, the Urnfield culture does provide a convenient background for the emergence of the Celts·of western Europe, the Celtic-speaking Lepontians of the Golasecca culture of northern Italy, and it is also dispersed down the length of Italy where we might expect to find the ancestors of the Italic groups. Such a model of Italic origins would at least accommodate those linguists who suggest that Italic and Celtic shared a particularly close dialectal association before their emergence as separate stocks.
But the problem of non-IE Etruscans participating in the same cultural phenomenon as well argues that there is no clear archaeological model in which one can discern either IE intrusions or differentiate IE-speakers from non-Indo-Europeans in the immediate- protohistoric period.