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paoloferrari
07-26-2017, 05:43 PM
Contacts in the last 90,000 years over the Strait of Gibraltar evidenced by genetic analysis of wild boar (Sus scrofa)

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0181929

"Abstract

Contacts across the Strait of Gibraltar in the Pleistocene have been studied in different research papers, which have demonstrated that this apparent barrier has been permeable to human and fauna movements in both directions. Our study, based on the genetic analysis of wild boar (Sus scrofa), suggests that there has been contact between Africa and Europe through the Strait of Gibraltar in the Late Pleistocene (at least in the last 90,000 years), as shown by the partial analysis of mitochondrial DNA. Cytochrome b and the control region from North African wild boar indicate a close relationship with European wild boar, and even some specimens belong to a common haplotype in Europe. The analyses suggest the transformation of the wild boar phylogeography in North Africa by the emergence of a natural communication route in times when sea levels fell due to climatic changes, and possibly through human action, since contacts coincide with both the Last Glacial period and the increasing human dispersion via the strait."

"In any case, the North African wild boar (Sus scrofa) is closely related to the European wild boar, which indicates a strong gene flow [20,21], but no studies exist have focused on the possible routes of these contacts"

"The role of the Strait of Gibraltar as a marine permeable barrier between Europe and Africa

The results are interesting because it would be more logical for North African wild boars to share their haplotypes with those of Egypt, Sudan, or even with those of the Near East, due to connectivity by land. However, all their haplotypes are European, except for CR182"

"Contacts across the Strait of Gibraltar could have been possible during glacial periods when sea level fell and it was easier to cross. The Last Glacial Maximum, the maximum extent of glaciation during the Last Glacial period, occurred during the interval between 25,000 and 18,000 years ago [17,19], and the Last Glacial period finished 11,700 years ago. The Late Glacial, the beginning of the modern warm period, began approximately 13,000 years ago [58], but the rise in temperatures was gradual. During cold periods, the currents in the strait would have been minimal or inexistent, which would have facilitated crossing the strait"

"it would appear that the South region of the Iberian Peninsula and North Africa form part of a refugial subcentre denominated Atlanto-Mediterranean, from which species could have recolonised areas in North of Europe at the beginning of the post-glacial periods "