An academic team comprised of Turkish, United States and French scientists have discovered a Turkey-dominated continent that disappeared about 40 million years ago. The team has given the continent the name "Balkanatolia" ("Balkanadolu" in Turkish), as it covers the Balkans and Anatolia.
The authors of the study published in the journal Earth Science Reviews explained that the Balkanatolia continent may have allowed Asian mammals, which had previously been separated from neighboring continents, to colonize Europe about 34 million years ago, Turkish daily Akşam reported.
According to the team, a major glaciation 34 million years ago likely led to the formation of the Antarctic ice sheet, causing sea levels to drop in the process and connecting Balkanatolia to western Europe. After that, more than two-thirds of mammals in Africa and the Arabian Peninsula disappeared during the Eocene-Oligocene (55 to 34 million years ago) transition marked by global cooling and sea-level declines.
Also in Eurasia, these global environmental impacts led to the mass extinction of marine organisms, plants and land animals, known as the "Grande Coupure."
Over millions of years during the Eocene epoch, western Europe and East Asia formed two distinct landmasses with very different mammalian fauna.
For example, European forests were home to indigenous fauna such as the Palaeotheres, an extinct group distantly related to modern-day horses but more similar to modern-day tapirs, while Asia had a more diverse fauna, including mammal families today found on both continents.
In the events called the Grande Coupure, about 34 million years ago, western Europe was colonized by later Asian species, leading to a massive renewal of vertebrate fauna and extinction of native mammals.
However, fossils found in the Balkans suggest an earlier colonization, where Asian mammals were found in southern Europe between 5 and 10 million years before the Grande Coupure, confusing scientists.
The team of French, United States and Turkish paleontologists and geologists, led by researchers from the National Center for Scientific Research (CNRS), think they have found the answer.
Scientists have discovered a new fossil bed in Turkey, called Büyükteflek, dating back 38 to 35 million years. Home to mammals of Asian origin, the bed has the earliest fossils ever discovered in Anatolia. In addition, the researchers found jaw fragments of brontotheres, an animal similar to large rhinoceroses that died out at the end of the Eocene, in the area.
This led scientists to conclude that Balkanatolia was colonized by Asian mammals some 40 million years ago as a result of geographical changes that are not yet fully understood.
As a result, the researchers said, about 6 million years later, a major glaciation lowered sea levels, connecting Balkanatolia to western Europe and allowing Asian mammals to colonize the continent, the study said.
"We show that this dispersal event presumably heralded faunal transformations in western Europe that preceded the Grande Coupure, and therefore indicates that the history of the species began as early as the middle Eocene of the southern route of Eurasia," the study authors wrote.
