A Jawbone in a Bunker
In 1944, as German forces constructed a wartime bunker in Pyrgos Vassilissis, northwest of Athens, they unearthed a fossilized lower jawbone, or mandible. This specimen, later named Graecopithecus freybergi, would sit for decades as a poorly understood piece of the hominid puzzle. A 2017 analysis, however, dated the mandible to 7.175 million years ago and proposed a controversial identity for its owner, nicknamed 'El Graeco': not an ape, but perhaps the oldest known pre-human, or hominin.
The evidence is within the jaw. A research team led by Madelaine Böhme and Nikolai Spassov used computer tomography to visualize the internal structure of the teeth. They discovered that the roots of the fourth premolar were partially fused. While great apes almost always have two or three separate, diverging roots on this tooth, fused roots are a distinctive feature of early and modern humans, including hominins like Ardipithecus and Australopithecus. This single anatomical detail places Graecopithecus as a candidate for a direct human ancestor.
The Savannahs of Miocene Europe
The case for Graecopithecus is supported by a second fossil, an upper premolar found in Azmaka, Bulgaria, dated to be slightly older at 7.24 million years. Together, these fossils suggest a population of early hominins living in southeastern Europe during the late Miocene epoch. Geological analysis of the fossil sites in both Greece and Bulgaria indicates an environment very different from today's. Microscopic plant particles and charcoal fragments show that Graecopithecus lived in a savanna biome, with C4-grasses and woodlands.
This environment matters because a leading theory of human evolution, the "savanna hypothesis," suggests that our ancestors were prompted to walk upright as African forests receded and grasslands expanded. A potential hominin in a European savanna complicates this narrative. The researchers behind the claim have dubbed their theory the "North Side Story." They argue that dramatic climate shifts, including the formation of the Sahara desert and the partial desiccation of the Mediterranean Sea during a period known as the Messinian Salinity Crisis, drove the evolutionary split between the ancestors of chimpanzees and humans in the Mediterranean, not Africa. Many paleoanthropologists, however, remain skeptical, arguing the evidence is too scarce and that fused roots could be an example of convergent evolution. The consensus still points to an African origin for the human lineage.