A new study seems to solve what is considered as a paradox concerning the evolutionary history of pigs. The latter has in fact been domesticated for the first time in the Near East and therefore today’s pigs should resemble genetically wild boars in this area. However, this is not the case: today’s European pigs resemble, at a genetic level, mostly European boars rather than those of the Near East.
The researchers analyzed the DNA signatures of more than 2,000 ancient pigs, traces collected over the years in the areas of the Near East and Europe and dating back to the last 10,000 years.
The results show that pigs arrived in Europe 8000 years ago and at that time showed genetic correlations with those of the Near East. However, with the passage of time, there has also been a hybridization with the European boar and this has meant that the traces of the DNA changed so much that they could no longer find, or almost today, traces of the wild boars of the East.
This study, therefore, declares that the traces of wild boar originating from the Near East have instead remained in the DNA of today’s European pigs and this would also be explained in some particular characteristics relating to the color of the coat.
The researchers also found that higher levels of similarity with boars from the Near East were found in pigs on Mediterranean islands, which could be explained by the fact that the populations of these places had minor exchanges with other populations of the European mainland, which has also seen in parallel also minor hybridizations between the wild boars of these islands and the European ones.
This research is also important because it shows that with today’s techniques it is now possible to see the history of the entire genome of a species in the “slow motion” and with a large level of detail.
Laurent Frantz, lead author of the study and researcher at Queen Mary University in London states the following: “We have all been taught that the great change was the initial process of domestication, but our data suggest that almost none of the human selection compared to the first 2,500 years of domestication of pigs have been important in the development of modern European commercial pigs.”