Great apes survived in Europe for two million years longer than previously thought, study of a tooth has revealed.
Scientists from Germany, Bulgaria and France say the hominid pre-molar, discovered near the Bulgarian town of Chirpan, is seven million years old.
The discovery may mean that scientists need to re-evaluate theories about some major steps in hominid evolution.
Up to now, it's been assumed that great apes became extinct in Europe at least nine million years ago because of changing climatic and environmental conditions.
Until now, the most recent hominid fossil found in Europe was that of a 9.2 million year old specimen of Ouranopithecus macedonensis from Greece. Back then, European terrestrial ecosystems had changed from lush, evergreen forests to savannah-like landscapes with a seasonal climate.
It had been thought that great apes, which typically eat fruit, hadn't survived because of a lack of food.
However, alongside the hominid tooth, the scientists found the remains of animals typical of a savannah - several species of elephant, giraffes, gazelles, antelopes, rhinos, and saber-toothed cats. The implication is that the hominids had adapted efficiently.
And the theory's backed up by electron microscope analysis of the tooth, which shows the hominid had been eating abrasive objects such as grass, seeds, and nuts.
The discovery may even cast doubt on the 'out of Africa' theory of human evolution, which suggests that humans evolved in Africa before migrating to the rest of the world.
"We now also need to rethink where the origin of humans took place," says Professor Madelaine Böhme of the University of Tübingen. "There is increasing evidence... that a significant part of human evolution happened outside Africa, in Europe and western Asia."