A jawbone estimated to be approximately 1.8 million years old has been discovered in the Republic of Georgia, potentially representing one of the earliest instances of the human species Homo erectus living outside Africa. The announcement was made on July 31, 2023, by the Georgian National Agency for Cultural Heritage Preservation, marking a significant milestone in the study of human evolution and migrations.
Located at the early Stone Age site of Orozmani, about 60 miles (100 kilometers) south of Tbilisi, the capital of Georgia, this finding is expected to provide insights into how early hominins migrated out of Africa. Giorgi Bidzinashvili, an archaeologist at Ilia State University who has been leading excavations at Orozmani since 2020, emphasized the potential implications of this discovery in an email to Live Science.
In initial excavations, researchers unearthed stone tools alongside ancient animal bones, as well as a single tooth attributed to Homo erectus in 2022. Bidzinashvili noted the significance of these findings, suggesting that they could indicate a broader distribution of Homo erectus in the region shortly after they left Africa.
Connecting the Dots of Human Migration
The evolutionary timeline of Homo erectus indicates that this species first emerged around 2 million years ago in Africa, being the first human ancestor known to have migrated beyond the continent. The earliest fossil evidence of such migrations comes from the site of Dmanisi, located just 12 miles (19 km) from Orozmani. Research conducted in 2011 confirmed that both Dmanisi and Orozmani date back to a similar time frame, between 1.825 million and 1.765 million years ago.
Excavations at Dmanisi over the past three decades have unveiled more than 100 fossil bones, including five skulls. These findings revealed that the earliest hominins to leave Africa were notably shorter and had smaller brain sizes compared to modern humans. Initially classified as a distinct species known as Homo georgicus, the Dmanisi skeletons are now recognized as among the earliest known Homo erectus individuals in Eurasia.
The recent findings at Orozmani, though not as extensive as those at Dmanisi, introduce the possibility that multiple early human groups may have settled in the Caucasus region during this period. Bidzinashvili remarked on the need for further analysis, as the jawbone has not yet been cleaned or compared with the tooth found in 2022.
Broader Implications for Human Evolution
The discovery raises intriguing questions about the patterns of early human migration. Karen Baab, a biological anthropologist at Midwestern University in Glendale, Arizona, stated that this could signify a more widespread distribution of Homo erectus during this era rather than isolated incidents.
The research team is currently focused on determining whether the fossils found at Orozmani predate those at Dmanisi or if they are from the same time period. As Bidzinashvili explained, “Until we have new dates, we can neither confirm nor deny that the Orozmani human fossils are older than Dmanisi or contemporaneous. By the end of the year, we will know.”
This recent discovery not only enhances our understanding of human ancestry but also opens up new avenues for research into the migratory patterns of our ancient relatives. The implications of this jawbone could redefine how we view the early movement of Homo species across continents.
