The archaeological sites of the Awash and Omo valleys, the Konso Gardulla, Melka Kunture are living witnesses to the fact that Ethiopia is the origin of mankind and human technologies as findings confirmed they existed in the country longer than almost anywhere else in the world.
Particularly, the Awash Valley is the early home of human ancestors, the hominids. It is one of the best open-air museums in the world in which the early direct human ancestors lived before millions of years. Moreover, it is the place of early human technologies-the Stone Age technologies-for the handyman lived there before millions of years.
Recently, a team of researchers discovered a remarkable new complete cranium of a 3.8 million-year-old early human ancestor referred to as MRD from the Woranso-Mille paleontological site located in Afar region of Ethiopia.
Dr. Yohannes Haile-Sellasie, Cleveland Museum of Natural History Curator and Adjunct Professor at Case Western Reserve University and his team of researchers stated that working for the past 15 years at the site, the team discovered the cranium (MRD-VP-1/1) in February 2016. MRD represents a time interval between 4.1 and 3.6 million years ago when early human ancestor fossils are rare especially outside the Woranso-Mille area.
MRD shows Lucy species and its hypothesized ancestor. An anamenesis co-existed for approximately 100,000 years, challenging previous assumptions of a linear transition between these two early human ancestors, Yohannes said. “This is a game-changer in our understanding of human evolution during Pliocene.”
Beverly Saylor of Case Western Reserve University and her colleagues determined the age of the fossil as 3.8 million years by dating minerals in layers of volcanic rocks nearby.
The discovery will help to offer new information on the earliest development of the Australopithecus group. Australopithecus anamensis and its descendent species, the well-known Australopithecus afarensis, co-existed for a period of at least 100 thousand years. This finding contradicts the long-held notion of anagenetic relationship between these two taxa, whereby one species disappears only by giving rise to a new species in a linear fashion.
In the years following their discovery, paleoanthropologists of the project conducted extensive analyses of MRD, while project geologists worked on determining the age and context of the specimen. It is stated that MRD generates new information on the overall craniofacial morphology of Australopithecus anamensis, a species that is widely accepted to have been the ancestor of Lucy’s species, Australopithecus afarensis.
The Woranso-Mille project has been conducting field research in the central Afar region of Ethiopia since 2004. The project has collected more than 12,600 fossil specimens representing about 85 mammalian species. The fossil collection includes about 230 fossil hominine specimens dating to between 3.0 and greater than 3.8 million years ago.
The first piece of MRD, the upper jaw, was found by Ali Bereino (a local Afar worker) on February 10, 2016, at a locality known as Miro Dora. The specimen was exposed on the surface and further investigation of the area resulted in the recovery of the rest of the cranium. “I couldn’t believe my eyes when I spotted the rest of the cranium. It was eureka moment and a dream comes true”, said Yohannes.
Beverly Saylor of Case Western Reserve University and her colleagues mapped the dated levels to the fossil site using field observations and the chemistry and magnetic properties of rock layers. They combined the field observations with analysis of microscopic biological remains to reconstruct the landscape, vegetation, and hydrology where MRD died.
Australopithecus anamnesis is the oldest known member of the genus Australopithecus. The species was previously only known through teeth and jaw fragments, all dated to between 4.2 and 3.9 million years ago. The similarities between the preserved dentition of the 3.8-million-year-old MRD and the previously known teeth and jaw fragments of A.anamensis led to a positive identification of MRD as a member of A. anamensis.
Additionally, due to the cranium’s rare near-complete state, the researchers identified never-before-seen facial features in the species. “MRD has a mix of primitive and derived facial and cranial features that I didn’t expect to see on a single individual”, Yohannes said.
Some characteristics were shared with its descendant species, Australopithecus afarensis, while others differed significantly and had more in common with those of even older and more primitive early human ancestor groups such as Ardipithecus and Sahelanthropus.
The Ethiopian Herald September 5, 2019
BY TSEGAYE TILAHUN
