JERUSALEM — Israel may not be the most obvious place to study pigs, given that religious strictures in both Judaism and Islam forbid their consumption.
But Israeli researchers involved in a lengthy project whose goal is to reconstruct ancient Israel have now established that the pigs here are of European stock, unlike their Middle Eastern counterparts elsewhere in the region, and that they probably arrived with the non-kosher Philistines about 3,000 years ago.
In the highlands west of the Jordan River associated with the early Israelites, archaeological studies have shown that there are almost no ancient pig bones. The exceptionally high number of pig bones found in the lowlands, at what were urban Philistine sites like Ashkelon and Ekron, have given rise to the theory that the Philistines, sea people who migrated here from the Aegean basin, brought their culinary and husbandry habits with them.
A new study based on DNA testing of modern and ancient pigs has revealed that the European emigrant pigs became prominent during the Iron Age, around 900 B.C., and eventually took over the entire wild boar population in the area that is now Israel.
The study, published Monday in the journal Scientific Reports, is part of a long-term project in which Israeli researchers are examining the large migrations, trade, climate changes and other forces that shaped and changed the Levant in antiquity.
Understanding human and animal movement is crucial to that process, said Israel Finkelstein, a professor at Tel Aviv University’s Institute of Archaeology, who directs the project. “We archaeologists know that pigs and pork consumption are two very good markers of ethnicity and identity,” Professor Finkelstein said, given the pig taboo in ancient Israel.
Waste-eating pigs may have been good for keeping ships clean, he said, but they could not move great distances over land, so raising pigs might have become a marker distinguishing the Israelites, who were originally pastoral nomads, from sedentary societies. At the time when animosity developed between the highlands and the lowlands, as depicted in biblical stories like the battle between David and the Philistine giant Goliath, pigs could have symbolized a “we and they” theme, Professor Finkelstein said, as in, “They eat pork, and we don’t.”
(To complicate matters, archaeologists have found pig bones at later Israelite sites from around 800 B.C., indicating that not all Israelites were strictly kosher.)
The researchers began more than two years ago by mapping the modern wild boar population of Israel. Meirav Meiri, an expert in ancient DNA, tested preserved pig samples from all over the country — a piece of an ear, a sliver of skin — and found that all possessed the European gene signature. That came as a surprise, she said, given that studies of pigs in nearby countries like Egypt, Iran, Iraq, Syria and Turkey had shown they were all of a Middle Eastern gene type.
European and Middle Eastern pigs do not look much different, but the DNA results raised the question of how the “Ashkenazi” pigs of European stock got here.
Working back through centuries of pig bones and teeth gathered from various collections and archaeological sites, Dr. Meiri painstakingly tested 177 ancient samples, including 34 with DNA preserved well enough to determine their genetic origin.
Large numbers of European pigs appeared in Israel around 900 B.C. and became more and more dominant until they had taken over completely. “Once we had a local signature,” Dr. Meiri said of the genetic makeup of the pigs found here in antiquity, but that “no longer exists.”
The researchers assume that the Philistines brought domesticated pigs with them and that some of those pigs may have run off into the wild and mixed with the local population. But for the European pigs to have taken over so completely, the experts say, there may have been more waves of emigrant pigs from Europe, from the time of the Romans onward.
“Here, there’s an island of pigs with European ancestry,” said Steve Weiner, a professor at the Weizmann Institute of Science in Rehovot, Israel, who is a partner in the project, which is funded by a grant from the European Research Council. “We don’t know if Napoleon brought pigs, or the Crusaders, or if they all did.”
“Archaeologists,” he concluded, “take pigs very seriously.”
