Pig Domestication and Human-Mediated Dispersal in Western Eurasia Revealed through Ancient DNA and Geometric Morphometrics

Abstract

Zooarcheological evidence suggests that pigs were domesticated in Southwest Asia ∼8,500 BC. They then spread across the Middle and Near East and westward into Europe alongside early agriculturalists. European pigs were either domesticated independently or more likely appeared so as a result of admixture between introduced pigs and European wild boar. As a result, European wild boar mtDNA lineages replaced Near Eastern/Anatolian mtDNA signatures in Europe and subsequently replaced indigenous domestic pig lineages in Anatolia. The specific details of these processes, however, remain unknown. To address questions related to early pig domestication, dispersal, and turnover in the Near East, we analyzed ancient mitochondrial DNA and dental geometric morphometric variation in 393 ancient pig specimens representing 48 archeological sites (from the Pre-Pottery Neolithic to the Medieval period) from Armenia, Cyprus, Georgia, Iran, Syria, and Turkey. Our results reveal the first genetic signatures of early domestic pigs in the Near Eastern Neolithic core zone. We also demonstrate that these early pigs differed genetically from those in western Anatolia that were introduced to Europe during the Neolithic expansion. In addition, we present a significantly more refined chronology for the introduction of European domestic pigs into Asia Minor that took place during the Bronze Age, at least 900 years earlier than previously detected. By the 5th century AD, European signatures completely replaced the endemic lineages possibly coinciding with the widespread demographic and societal changes that occurred during the Anatolian Bronze and Iron Ages.

Like a pig out of water: seaborne spread of domestic pigs in Southern Italy and Sardinia during the Bronze and Iron Ages

“…The same people may have later intentionally dispersed the European haplotype into the Levant during the Iron Age. Indeed, the major turnover in the Near Eastern pig population took place around 900 BC, when the European haplotype became predominant in the Southern Levant (Meiri et al, 2013), in Anatolia (Ottoni et al, 2013) and Romania (Evin et al, 2015). A similar scenario has been proposed for the Eastern Mediterranean origin of cattle in Etruria (Central Italy) introduced in this region by navigation during the Late Bronze (Pellecchia et al, 2007).…”

Mining the pig genome to investigate the domestication process

“…In an attempt to clarify the timeline of the population dynamics of Near Eastern pigs, Ottoni et al (2013) used a powerful approach based on the analysis of ancient mitochondrial DNA and dental geometric and morphometric data obtained from 393 specimens from 48 archaeological sites. In doing so, they demonstrated that the European Neolithic pig remains carried NE2 haplotypes that are native to Anatolia, thus identifying this geographic location as the main centre of Near Eastern pig dispersal into Europe (Figure 1).…”

“…Thus, the development of techniques that allow for the high-throughput sequencing of ancient nuclear DNA would be crucial to circumvent this limitation. Currently, the number of ancient populations sampled is quite limited, and we have explored only the mitochondrial variation within these populations (Larson et al, 2007b;Ottoni et al, 2013). Third-generation sequencing platforms, which allow for the sequencing of single DNA molecules without an intermediary amplification step, may have a fundamental role in characterizing the autosomal genomes of ancient pig specimens (Rizzi et al, 2012).…”

Maintaining genetic integrity of coexisting wild and domestic populations: Genetic differentiation between wild and domestic Rangifer with long traditions of intentional interbreeding

“…However, new models of domestication suggest that while spatial separation of wild and domestic types is often sought, various domestic species ranging from pigs to horses have also been cross‐bred for specific characteristics by allowing controlled introgression from wild herds. (Ottoni, 2013; Jónsson, 2014; Frantz, 2015). For most domestic breeds, this idea remains a hypothesis as the original free‐ranging wild forms have become largely extinct or restricted to a few isolated areas (Clutton‐Brock, 1987).…”