The study found that in this particular area the Greek colonists represented 18% of the total population during the Hellenic period, compared to 82% indigenous Italians:
It concludes, moreover, that the biological composition of Southern Italy remained relatively unchanged by the Greek colonization:
In addition to being few in number in Southern Italy broadly speaking, the ancient Hellenic colonies themselves were not ethnically homogenous: that is to say, the colonies were inhabited both by Greeks and by indigenous Italians, thereby diluting the Greek element. Indeed, according to the study, the indigenous Italics far outnumbered the Greeks in the colonies, so much so that the ancient Hellenes would have been a minority even within their own city-states. It should be noted that Taras (present-day Taranto) was by far the largest Hellenic colony in ancient Southern Italy; during the Hellenistic period, therefore, the largest concentration of Greeks would have been found in this area. Yet, as per the findings, their figure is placed at only 18% in this region.
This already-low figure would have fallen considerably following the Roman conquest and establishment of Latin colonies from the 3rd century BC onward. However, this study limits itself only to the pre-Hellenic period and post-colonial Hellenic period in the Gulf of Taranto — in short, it concerns only the pre-Roman period, so it does not assess the effects which the Roman colonization brought to this area of the South. It is certain, though, that with the Roman conquest the overall percentage of Greeks would have greatly decreased, inasmuch as Latin colonies were established in part to demographically replace Greeks, facilitate Latinization and solidify Roman power over the territory.
It must be borne in mind, also, that the study concerns only the selected areas of southern Basilicata and southern Puglia shown in the maps below. It therefore does not cover Sicily, Calabria or Campania, nor does it cover the whole of Basilicata, nor the whole of Puglia, let alone all of Southern Italy. Naturally, if one were to take into account the entirety of Southern Italy, the figure of 18% would drop enormously and become minuscule, given that the entire interior of the country was densely populated by Italic peoples (see this map, taken from Sewell & Witcher 2015).
“About 18% of the people [in this area] in post-colonial times were of Greek ancestry and lived equally distributed across Greek colonies and indigenous villages.”
It concludes, moreover, that the biological composition of Southern Italy remained relatively unchanged by the Greek colonization:
“Nevertheless, the overall biological composition and variability of southern Italy remained relatively unchanged across pre- and post-colonial periods. Our results support a scenario in which only few Greek colonists migrated to southern Italy and lived in smaller numbers alongside indigenous people in Greek colonies as well as in indigenous villages. Our results contradict a scenario in which large numbers of Greek invaders founded biologically isolated and substantially homogeneous colonial enclaves within conquered territories.”
In addition to being few in number in Southern Italy broadly speaking, the ancient Hellenic colonies themselves were not ethnically homogenous: that is to say, the colonies were inhabited both by Greeks and by indigenous Italians, thereby diluting the Greek element. Indeed, according to the study, the indigenous Italics far outnumbered the Greeks in the colonies, so much so that the ancient Hellenes would have been a minority even within their own city-states. It should be noted that Taras (present-day Taranto) was by far the largest Hellenic colony in ancient Southern Italy; during the Hellenistic period, therefore, the largest concentration of Greeks would have been found in this area. Yet, as per the findings, their figure is placed at only 18% in this region.
This already-low figure would have fallen considerably following the Roman conquest and establishment of Latin colonies from the 3rd century BC onward. However, this study limits itself only to the pre-Hellenic period and post-colonial Hellenic period in the Gulf of Taranto — in short, it concerns only the pre-Roman period, so it does not assess the effects which the Roman colonization brought to this area of the South. It is certain, though, that with the Roman conquest the overall percentage of Greeks would have greatly decreased, inasmuch as Latin colonies were established in part to demographically replace Greeks, facilitate Latinization and solidify Roman power over the territory.
It must be borne in mind, also, that the study concerns only the selected areas of southern Basilicata and southern Puglia shown in the maps below. It therefore does not cover Sicily, Calabria or Campania, nor does it cover the whole of Basilicata, nor the whole of Puglia, let alone all of Southern Italy. Naturally, if one were to take into account the entirety of Southern Italy, the figure of 18% would drop enormously and become minuscule, given that the entire interior of the country was densely populated by Italic peoples (see this map, taken from Sewell & Witcher 2015).
Here are the areas covered by this study and the findings:
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Area examined by Rathmann et al. (2019) |
The following is a long extract which explains the results:
Finally, the authors of this study also cast explicit doubt on an earlier DNA study by Di Gaetano et al. (2009) which previously claimed that the Greek genetic contribution in Sicily amounted to 37%, on the basis — and rather questionable assumption — that E-V13 is a specifically “Greek” haplogroup:
PDF (full text): Population History of Southern Italy During Greek Colonization Inferred from Dental Remains — Rathmann et al. 2019
“One scenario, largely drawn from ancient written sources, envisages Greek colonization as a mass migration of invaders who founded biologically isolated and substantially homogeneous enclaves within conquered territories. In this scenario, indigenous populations were deprived of land, resources, and occasionally women to fulfill the colonies’ needs, while being the object of gradual acculturation (or “Hellenization”)... An alternative scenario, based on archaeological evidence and the adoption of post-colonial theory, envisages Greek colonization as a more gradual process, where only few Greek colonists (mostly traders, artisans, and adventurers) sailed to the shores of southern Italy and lived peacefully alongside a much larger indigenous population. In this scenario, close collaboration resulted in intermarriage between newcomers and locals and eventually shaped new, admixed cultures. ...
In recent years, demographers and geneticists have tried to tackle the question of Greek colonization and its impact on southern Italy from a different angle using census sizes documented in ancient texts and/or modern DNA data from present-day Italians. However, whereas some studies estimated a rather large number of Greek migrants (e.g., Scheidel, 2003), others have suggested a substantially smaller founding population (e.g., Tofanelli et al., 2016). ...
One major problem with the various arguments put forward in support of both scenarios is that they are exclusively based on indirect evidence, namely: (a) ancient texts from Greek writers; (b) archaeological objects excavated in Italy, primarily pottery; and (c) modern DNA profiles of present-day southern Italians. To rely on this evidence alone is problematic because most ancient written sources postdate Greek colonization by several centuries and portray it solely from a Greek perspective. Similarly, movements of archaeological objects do not necessarily imply migration but can also result from trade or the diffusion and adoption of stylistic fashions. Finally, present-day DNA profiles may not accurately reflect the effects of past migration events due to movements of people in more recent times. ...
Surprisingly, only a handful of studies have utilized biodistance methods to address the impact of Greek colonization on southern Italy (Henneberg, 1998; Rathmann, Saltini Semerari, & Harvati, 2017; Rubini, Bonafede, & Mogliazza, 1999). These investigations found that inhabitants of Greek colonies showed marked biological differences to indigenous Italian groups... While this is an exciting finding, these studies were limited by several factors. ... Finally, none of the previous studies used adequate comparative data from Greece, which is essential to quantifying the degree of Greek genetic contribution to southern Italy. ...
If the colonization process was driven by large groups of Greeks founding biologically isolated and substantially homogeneous enclaves within southern Italy (Scenario 1), then we would expect to see... that inhabitants of Greek colonies are biologically different from indigenous populations, with the former exhibiting lower levels of variability than the latter (due to isolation and genetic drift). Moreover, we would expect that Greek colonies are predominantly inhabited by individuals of Greek ancestry whereas indigenous villages are predominantly inhabited by individuals of Italian ancestry. Lastly, we would expect to see a general increase in biological variability and a change in the overall biological composition of southern Italy from the pre-colonial period to the post-colonial period (due to the transfer of new genes into the southern Italian gene pool). ...
Alternatively, if only few Greek colonists migrated to southern Italy and lived in small numbers alongside indigenous people in Greek colonies as well as in indigenous villages (Scenario 2), then we would expect to see... that inhabitants of Greek colonies are biologically similar to indigenous populations with both exhibiting similar levels of variability (due to the homogenizing effect of gene flow). ... Lastly, we would expect to see similar levels of biological variability and a largely unchanged overall biological composition of southern Italy from the pre-colonial to the post-colonial period (because numerically negligible gene flow will not significantly alter the southern Italian gene pool). ...
Validation of the naïve Bayes ancestry classification model revealed that Italians and Greeks of known ancestry in the training data were correctly classified in 80% of cases, which corresponds to a misclassification rate of 20%... The model misclassified Greeks more often (23%) than Italians (17%). ... Overall, classification identified the majority of the test individuals as Italian (82%) and only a few as Greek (18%). ...In this study, we aimed at evaluating competing scenarios regarding the ancient Greek colonization of southern Italy. For this purpose we applied a set of individual-level biodistance analyses to a comprehensive dataset of archaeological human dental remains from several Greek colonies and indigenous settlements along the Gulf of Taranto. We found that... About 18% of the people in post-colonial southern Italy [ed.: in the Gulf of Taranto area, not all of Southern Italy] were of Greek ancestry (revealed by naïve Bayes classification). These people lived equally distributed across Greek colonies and indigenous settlements. Nevertheless, we found that the overall biological composition and variability of southern Italy remained relatively unchanged across pre- and post-colonial periods (as measured by PERMANOVA and Betadisper analyses). ...Taken together, our results support a colonization scenario in which few Greek colonists settled in southern Italy and lived in small numbers alongside indigenous people in Greek colonies as well as in indigenous settlements. This scenario is favored by scholars inspired by post-colonial theory who have challenged the traditional colonial narratives surviving in ancient Greek texts and consider the colonization process as an interplay of actions of both colonizers and colonized. It is also supported by several archaeological discoveries associated with the early phases of Greek colonization, indicating close interaction between the first generations of Greek newcomers and local Italic populations. For example, settlement and burial data from Siris suggest that the early colony was an open, dispersed village with burial plots including a mix of Greek- and indigenous-style funerary practices. A similar conclusion was drawn from the archaeological evidence from the early colony of Taras. ...
Our results contradict a colonization scenario in which large numbers of Greek invaders founded biologically isolated and substantially homogeneous colonial settlements in hostile native lands. This more traditional interpretation of Greek colonization is largely based on ancient written sources from Greek writers. ... In this framework, the role of local populations, if at all considered, is essentially passive. ...
We estimated an overall Greek contribution of 18% to the population of southern Italy along the Gulf of Taranto during the post-colonial period (700–200 BC). Our estimated Greek contribution is close to the size spectrum proposed by historical demographers, who suggested 10% Greeks in pre-Roman southern Italy (Beloch, 1886). Our finding is also in line with preliminary strontium isotopic evidence, indicating that 10% (n = 20) of the post-colonial individuals in the study region are of non-local origin (Vos, 2018). Interestingly, our results also broadly agree with biodistance and isotopic studies conducted at other Greek colonies across the Mediterranean Basin (Keenleyside, Schwarcz, & Panayotova, 2011; McIlvaine et al., 2014; Stallo, Schepartz, Grimes, & Richards, 2010), which suggest that colonized territories were generally characterized by few Greek newcomers living alongside a much larger indigenous population.”
Finally, the authors of this study also cast explicit doubt on an earlier DNA study by Di Gaetano et al. (2009) which previously claimed that the Greek genetic contribution in Sicily amounted to 37%, on the basis — and rather questionable assumption — that E-V13 is a specifically “Greek” haplogroup:
“Our estimated Greek contribution of 18% differs from genomic estimates of the ancient Greek contribution to southern Italy derived from present-day DNA profiles. Di Gaetano et al. (2009) used the haplogroup lineage E-V13 to estimate a Greek contribution of 37% to the population of Sicily and attributed the migration influx to the Classical period (2,380 years before present, with a 95% confidence interval ranging between 6,940 and 675 years ago). A potential explanation for the discrepancy between our estimate and their genomic reconstruction could be that proportions of specific genetic lineages surviving in present-days populations may not be good proxies for assessing the effects of past migration events (Tofanelli et al., 2016). Moreover, their genomic estimate of the timing of the migration influx has a wide confidence interval spanning several millennia. The estimate provided in this study is directly derived from archaeological human remains and may therefore be a more accurate reconstruction of the initial Greek genetic contribution to southern Italy (but see further discussion below).”
PDF (full text): Population History of Southern Italy During Greek Colonization Inferred from Dental Remains — Rathmann et al. 2019
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