Scientists find 7.2 million year old bipedal hominid in Bulgaria

On March 4, 2026, the National Museum of Natural History, Sofia (NMNHS) gave a press conference in the BTA National Press Club in Sofia to present the article by Nikolai Spassov (NMNHS), Dionisios Youlatos (the Aristotle University of Thessaloniki, Greece), Madelaine Böhme (the Eberhard Karls University of Tübingen, Germany), Ralitsa Bogdanova (NMNHS), Latinka Hristova (NMNHS), David R. Begun (the University of Toronto, Canada): An early form of terrestrial hominine bipedalism in the late Miocene of Bulgaria, published in the journal Palaeobiodiversity and Palaeoenvironments. The conclusions reached by the authors of this study are quite unexpected and could change many aspects of the ideas about the earliest evolution of mankind.

The press conference was opened by the Director of the Museum, Prof. Pavel Stoev, who congratulated the authors on the epochal discovery and the success achieved. After him, Assoc. Prof. Ina Aneva, Scientific Secretary of the Biodiversity, Bioresources and Ecology Division of the Bulgarian Academy of Sciences, delivered a greeting on behalf of the Bulgarian Academy of Sciences. She noted that the discovery of Prof. Spasov and his team is a reason for special pride for the Academy. Decades of efforts and scientific courage to put forward hypotheses that change the framework of the debate, define the specific scientific profile of Prof. Spasov. He is a scientist who sees evolutionary trends, combining deep erudition, field experience and analytical precision and places Bulgarian paleontology at the center of the world media. Creator of a scientific school, with trained researchers, with traditions and a sustainable heritage.

“In the person of Prof. Spasov, the Bulgarian Academy of Sciences has a scientist who worthily represents our country in the global scientific dialogue, a researcher with vision, authority and contribution that goes beyond national frameworks and fits into the grand narrative of the history of life on Earth,” concluded Assoc. Prof. Aneva.

Then, Prof. Spasov presented the discovery and article, that describes a fossil femur from the late Miocene site of 7.2 million years old, Azmaka, near Chirpan (Bulgaria), tentatively attributed to the Balkan hominine Graecopithecus and may be the oldest known human. Bipedalism has long been considered a fundamental acquisition in human evolution and one of the most important of the main characteristics of hominins, the latest of which are humans. Until recently, it was considered that the first hominin capable of walking upright was the 7—6.5 Ma old Sahelanthropus, but the latest research casts doubt on the stated locomotor abilities of this hominid. Another African hominid – Orrorin, shows quite convincing signs of bipedalism, according to most researchers, but this Kenyan hominin existed more than one million years later than the hominid from Azmaka. For more than a hundred years, Africa has been considered the cradle of humanity, and the evidence for this is numerous and convincing. So convincing that it was difficult to accept any other possibility. There is indeed no doubt that the vast majority of humanity’s evolutionary path has passed on the African continent. But it seems that the first steps were taken in the Balkans. The natural environment shows a savannah landscape that was typical of the Late Miocene of the Balkans and of the Balkan-Iranian paleozoozoogeographic province of that time. The Balkans and Asia Minor are particularly important for the evolution and migration of species because they are a crossroads between three continents. There is increasing evidence that today’s savannah fauna of Africa is largely related to Eurasia in origin. Analyses from a previous study indicate that the time between approximately 8/7.5 and 5.5 million years ago was a time of mass migrations of a number of mammal species from the Balkan-Iranian-Afghan region to Africa, but there is no evidence of the reverse process at that time — migrations from the African continent to Eurasia. These migrations were caused by climate changes associated with the development of the Arabian Desert, which became a barrier to this faunal exchange between Eurasia and Africa about 5.3 million years ago. One of the migrants could be the aforementioned, already upright Balkan hominin. There is no longer any doubt that during the late Miocene, when the Balkans and the Near East were inhabited by Graecopithecus and its probable direct predecessors — Ouranopithecus from Northern Greece and Anadoluvius from Anatolia, a savannah stretched over a vast territory from Southeast Europe to Iran and Afghanistan (the so-called Balkan-Iranian paleozoogeographic province), with an appearance and fauna similar to those of today’s Africa. There is increasing evidence that with the opening of similar spaces in Africa, many of the Eurasian savannah inhabitants migrated to the African continent.

The quantitative and qualitative analysis of the features of the Azmaka femur convincingly show a unique combination of signs of terrestrial quadrupedal locomotion, with those indicating possibilities for bipedal walking. A number of morphological features of the found femur, such as the elongated femoral neck, the position of the gluteal tuberosity, the disappearance of the distal portion of the intertrochanteric crest, the presence of an intertrochanteric line, the low values of the angle between the body and the neck of the femur, the straight shaft of the bone and other features show similarity with bipedal fossil hominins and humans and distinguish it from the femora of arboreal apes. The Azmaka hominid is also distinguished from arboreal apes by the asymmetrical development of the cortex of the femoral neck, established by computed tomography scan.

Graecopithecus, first discovered at a site near Athens (Greece), lived in a savanna environment, like East Africa today, and probably needed to move bipedally to see across the horizon (scanning for both food and predators) and to carry important items. But this ape was not exactly modern human in the way it moved. The Azmaka femur combines attributes of terrestrial quadrupeds (knuckle-walkers), the African apes, and bipeds. It represents a stage in human evolution between our tree-living and ground-living ancestors that can fairly be called a missing link. Graecopithecus most likely descends from the older Balkan-Anatolian apes Ouranopithecus and Anadoluvius, which in turn evolved from ancestors in Western and Central Europe. With climate change these apes most probably moved by different waves into Africa to become the ancestors of the African apes (chimpanzees and gorillas) and humans. We know that today’s African savanna fauna largely originates from the late Miocene fauna of the Balkans and western Asia (Greece, Bulgaria, North Macedonia to Türkiye and Iran). These large scale movements of mammals to Africa, between 8 and 6 million years ago, were caused by aridification and the development of the Arabian Desert. The authors of the study suggest that Graecopithecus also migrated to Africa from the southern Balkans, which led to the origins of early human ancestors such as Ardipithecus and Lucy (Australopithecus afarensis). Work is continuing at Azmaka and other sites in the Balkans to learn more about the ecology and evolution of this surprising early biped and possible human ancestor.

Publication: Nikolai Spassov, Dionisios Youlatos, Madelaine Böhme, Ralitsa Bogdanova, Latinka Hristova, David R. Begun: An early form of terrestrial hominine bipedalism in the Late Miocene of Bulgaria. Palaeobiodiversity and Palaeoenvironments, https://doi.org/10.1007/s12549-025-00691-0.

Press conference record in Bulgarian: https://www.bta.bg/bg/pressclub/archive/34876.