Fifty million years ago, Balkanatolia was a separate continent from Europe and Asia, formed by various islands and covering the territories of the present Balkans and Anatolia.
The existence of this third Eurasian continent, sandwiched between Europe, Africa and Asia, was proposed by a group of French, American and Turkish paleontologists and geologists in the March issue of Earth-Science Reviews. He explains the transition of land animals from Asia to Europe during the transition between the Eocene and Oligocene, that is, about thirty-four million years ago.
During the Eocene, between 50 and 34 million years ago, Asia and Europe were two very different continents, where for millions of years there was no possibility of contact and exchange between animals.
Many fossils found in the region corresponding to today’s Balkans and Anatolia show that it was inhabited by a very specific terrestrial fauna found nowhere else. We are talking about “endemic fauna”. There were, for example, large herbivorous mammals resembling hippos and marsupials.
For researchers, the discovery of this unique fauna, not found in Europe or Asia, indicates that the region was a single landmass separated from neighboring continents.
Balkanatolia became associated with them as a result of, among other things, tectonic movements that occurred between 40 and 34 million years ago. These events led to the formation of a corridor through which the Asian fauna was able to conquer Europe.
Balkanatolia, the missing link explaining the distribution of Asian fauna? This is the most plausible scenario to date (read “Point from…” below). Paleontologists have also found evidence of early settlement of Asian animals in central Turkey.
There, more precisely in Buyukteflek, they found very specific fossils dating back 35-38 million years ago, that is, before the conquest of the west by Asian animals. These fossils, the oldest found to date in Anatolia, are fragments of the jaws of animals resembling large rhinos, brontotheres, undeniably Asian mammals.
geography and life
Here is a new example that not only sheds light on the trajectory of mammals, but also shows how geographic modifications shape the evolution of living beings and make it possible to understand what we have before our eyes today. Like the collision of Africa with the southern edge of Asia twenty million years ago, which brought elephants to Asia and rhinos to Africa.
Gregoire Mete, paleontologist at the Center for Paleontological Research (MNHN/Sorbonne University/CNRS)
“Sudden climate change”
What different mammals inhabited Asia and Europe over 40 million years ago when the two continents were completely separated?
In Europe, there were paleotheria—animals distantly related to our horses, primates, rodents, or even anoploters—like small cows, none of which have left direct descendants today. In Asia, the more modern fauna consisted of primitive forms of rhinos and ruminants, as well as great apes and various rodents, including the ancestors of our rats and mice.
Why didn’t European animals cross Balkanatolia to disperse into Asia?
It is true that paleontologists have never found paleotera or anoplothera fossils in Asia until now. Balkanatolia first came into contact with Asia, but, on the other hand, for a long time remained separated from Western Europe by a very deep sea. In addition, 40 million years ago, thanks to continental connections, Asian animals first settled in Balkanatolia, whose highly endemic fauna is replaced by these Asian aliens. It is for the second time, 34 million years ago, when the global cooling of the Earth occurs, that Balkanatolia is connected to Europe. This then allows Asian animals to enter Western Europe where they compete with endemic European animals.
How has dramatic climate change given Asian mammals an advantage?
European mammals have had to face the cumulative effects of severe climate change and competition from animals that perform better in drier environments with more distinct seasons. Let me explain: 34 million years ago, in addition to tectonic changes between Balkanatolia and Europe, there was an establishment of a cold ocean current around Antarctica, when south of South America separated from Antarctica. The climate in Europe became colder and the environment changed radically from forested and tropical to more open with more pronounced seasons, which favored the spread of Asian animals more familiar with this type of habitat.
Is there an alternative hypothesis for the existence of Balkanatolia that explains the appearance of Asian animals in Europe?
An alternative hypothesis suggests migration across the North Pole, but this hypothesis is not supported by any paleontological evidence. On the other hand, a very minor phenomenon of “rafting” probably took place to explain the origin of the endemic fauna of Balkanatolia. Indeed, small primates of Asian origin have been found in Balkanatolia, which probably arrived on natural rafts, a phenomenon currently observed in the tropics, when the banks of rivers in estuaries (and the animals living there!) break off and float across the sea from the current for hundreds kilometers. Rodents and primates often participate in dispersal phenomena through this fusion phenomenon. So, for example, Madagascar seems to have been colonized.