A group of French, American, and Turkish palaeontologists and geologists headed by CNRS researchers1 uncovered the presence of a long-forgotten continent known as Balkanatolia, which now encompasses the Balkans and Anatolia. They think it allowed animals from Asia to colonize Europe 34 million years ago because it was formerly home to a very unique fauna. Their results will be published in Earth Science Reviews in March 2022.
Western Europe and Eastern Asia formed two distinct land masses with very different mammalian faunas for millions of years during the Eocene Epoch (55 to 34 million years ago): European forests were home to endemic fauna such as Palaeotheres (an extinct group distantly related to modern horses but more like today’s tapirs), whereas Asia was populated by a more diverse fauna including the mammalian families found today on both continents.
We know that Asian animals colonized Western Europe some 34 million years ago, resulting in a large renewal of vertebrate fauna and the loss of its native mammals, a dramatic event known as the “Grande Coupure.” Surprisingly, fossils discovered in the Balkans reveal that Asian animals were in southern Europe long before the Grande Coupure, implying earlier colonization.
A group of CNRS researchers has now proposed an answer for this puzzle. To do so, scientists looked back at older palaeontological finds, some of which date back to the 19th century, and re-dated them based on new geological evidence. For most of the Eocene, the area corresponding to today’s Balkans and Anatolia had a terrestrial fauna that was homogenous yet different from that of Europe and eastern Asia, according to the study. Exotic fauna includes South American marsupials and Embrithopoda (giant herbivorous mammals resembling hippopotamuses) that were previously only seen in Africa. As a result, the area must have formed a singular land mass independent from the neighboring continents.
The scientists also uncovered a new fossil deposit in Turkey (Büyükteflek) that dates from 38 to 35 million years ago and contained animals with strong Asian affinities, which are the oldest mammals ever identified in Anatolia. They discovered jaw remains from Brontotheres, enormous rhinocerose-like creatures that went out at the end of the Eocene.
With all of this material, the team was able to sketch out the history of Balkanatolia, the third Eurasian continent wedged between Europe, Africa, and Asia. The continent, which had previously existed 50 million years ago2 and was home to a distinct fauna, was colonized by Asian animals 40 million years ago as a consequence of geographical changes that are yet unknown. A significant glacial 34 million years ago, which resulted in the construction of the Antarctic ice sheet and lowered sea levels, is thought to have linked Balkanatolia and Western Europe, resulting in the ‘Grande Coupure.’
1 Working at the CNRS/Aix-Marseille Université/IRD/INRAE Centre for Research and Teaching in Environmental Geoscience (CNRS/Aix-Marseille Université/IRD/INRAE) and the CNRS/Museum national d’Histoire naturelle/Sorbonne Université Centre for Research on Palaeontology (CNRS/Museum national d’Histoire naturelle/Sorbonne Université). Geosciences Rennes (CNRS/Université Rennes 1), as well as Kütahya Dumlupnar and Eskişehir Osmangazi Universities in Turkey, and the universities of Washington, Connecticut, Kansas, and Chicago, all participated to this study (USA).
2 Balkanatolia might be a vestige of Greater Adria, another of the Mediterranean region’s ‘lost continents,’ which formed over 200 million years ago and was discovered by Douwe van Hinsbergen et al. in a 2019 research based on tectonic plate reconstructions.