A newly reconstructed 1.5-million-year-old fossil from Ethiopia is offering rare insight into the earliest migrations of ancient human ancestors — and a Southern Connecticut State University researcher played a key role in the discovery.
Dr. Michael J. Rogers, professor of anthropology at Southern, is part of an international research team that has virtually reconstructed the most complete Early Pleistocene hominin cranium ever recovered from the Horn of Africa. The findings were published in Nature Communications on Dec. 16, 2025.
Rogers’ role in the project reflects Southern’s continued growth as a research-driven regional university. In 2025, Southern earned the Carnegie Classification “R2: High Research Activity,” recognizing the university’s expanding research infrastructure, faculty scholarship, and global collaborations.
The fossil, known as DAN5, was discovered at the site of Gona in Ethiopia’s Afar region and dates to approximately 1.5–1.6 million years ago. The reconstruction reveals a surprisingly archaic facial structure in Homo erectus, the species widely recognized as the first human ancestor to disperse beyond Africa.
A Rare Window into Early Human Evolution
The DAN5 fossil represents the first complete Early Pleistocene hominin cranium from the Horn of Africa. While earlier research had shown the fossil possessed a relatively small brain, the new reconstruction reveals that its face and teeth retain more primitive features than expected for Homo erectus of the same period.
According to lead author Dr. Karen L. Baab of Midwestern University, the findings suggest that some early populations of Homo erectus retained anatomical traits from earlier ancestors even after the species began migrating out of Africa.
“One explanation is that the Gona population retained the anatomy of the population that originally migrated out of Africa approximately 300,000 years earlier,” Baab said.
Cutting-Edge Virtual Reconstruction
The research team used high-resolution micro-CT scans of fossilized facial fragments and teeth recovered during fieldwork at Gona. Digital models of the fragments were reassembled virtually, then attached to an already documented fossil braincase to produce a nearly complete skull.
Baab described the process as “a very complicated 3D puzzle,” noting that the reconstruction took about a year and underwent several iterations before reaching its final form.
Southern’s Role in Global Research
Rogers is co-director of the Gona Paleoanthropological Research Project, which has uncovered hominin fossils dating back more than 6.3 million years and stone tools spanning 2.6 million years of human history. The project has provided some of the most significant evidence of early human evolution anywhere in the world.
The DAN5 fossil was also found in association with both Oldowan stone tools and early Acheulian handaxes — among the earliest evidence of these two tool traditions appearing together with a hominin fossil.
“It is remarkable that the DAN5 Homo erectus was making both simple Oldowan tools and early Acheulian handaxes,” said Dr. Sileshi Semaw, Rogers’ co-director on the project.
What Comes Next
Researchers hope to compare DAN5 with early human fossils from Europe, including those assigned to Homo erectus and Homo antecessor, to better understand how early humans adapted as they spread across continents.
“We’re going to need several more fossils dated between 2 and 1 million years ago to sort this out,” Rogers said.
