Smallest Homo Erectus Cranium in Africa, Diverse Stone Tools Discovered in Afar Region

ENA,March 5/2020 An international research team announced that it has found the smallest Homo erectus cranium in Africa and diverse stone tools in Gona study area of Afar Regional State. 

The team led by Sileshi Semaw of the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) in Spain and Michael Rogers of Southern Connecticut State University  revealed that they discovered a nearly-complete hominin cranium about 1.5 million years old, and a partial cranium dated to about 1.26 million years ago.

The smallest Homo erectus cranium in Africa, and the diverse stone tools found at Gona, show that human ancestors were more varied, both physically and behaviorally, than previously known, according to the researchers.

This physical diversity is mirrored by the stone tool technologies exhibited by the artifacts found in association with both crania.

Instead of only finding the expected large hand axes or picks, signature tools of H. erectus, the Gona team found both well-made hand axes and plenty of less-complex Oldowan tools and cores.

This suggests that H. erectus had a degree of cultural/behavioral plasticity that has yet to be fully understood.

The toolmakers at both sites lived in close proximity to ancient rivers, in settings with riverine woodlands adjacent to open habitats.

According to the researchers, both crania assigned to Homo erectus were associated with both simple Oldowan-type (Mode 1) and more complex, Acheulian (Mode 2) stone tool assemblages.

The nearly complete cranium was discovered at Dana Aoule North (DAN5), and the partial cranium at Busidima North (BSN12), sites that are 5.7 kilometers apart.

The research team has been investigating the Gona deposits since 1999, and the BSN12 partial cranium was discovered by N. Toth of Indiana University during the first season.

The DAN5 cranium was found a year later by the late Ibrahim Habib, a local Afar colleague, on a camel trail.

Remarkably, the scientists noted that the DAN5 cranium has the smallest endocranial volume documented for H. erectus in Africa, about 590 cubic centimeters, probably representing a female.

The BSN12 partial cranium is robust and large, while the DAN5 cranium is smaller and more gracile, suggesting that H. erectus was probably a sexually dimorphic species.

Gona, the site of the discovery,  is located in the Afar Triangular of Ethiopia, adjacent to the well-known Middle Awash and Hadar study areas, where the famous skeletons “Ardi” and “Luci” were found.