BY TSEGAI MEDIN
Let’s imagine for a moment on the present scenery of the Danakil Depression of Eritrea, the now place of the proud Afar people but home to our Human ancestor a million years from the present. What would you think? Would you think this area was once covered by forest with adjacent savannas and lake environment where large and medium-sized animals and humans inhabited? Would you think, that different types of animals – later extinct – from the once we know now, were living in this area. Would you think that this area was the most favorable place to live and evolve for any living creature before a million years or more?
Off course not, it is hard to imagine such environmental history really existed in the Danakil. Especially after knowing the Danakil is the hottest and most arid places on earth today.
Let’s continue envisaging even more. Can anyone imagine at this desert and hottest areas of the Danakil Depression of Eritrea a girl living along several animals, with no clothing and house to own but a sharp stone tool? This could be miraculous to many and at some point, senseless. But, for anthropologists, she is the mother of Eritreans and the present human population across the globe. I am referring her in this paper as “the lady of Buia”, a pretty and fearless girl inhabited the Buia Basin of the Danakil part of the Rift Valley a million years back from the present. The Eritrean Danakil which is part of African Rift Valley is preserving immense and unimaginable testimonies of our evolutionary history.
Majority of the Africa sites with evidence related to the evolution of our species are found alongside the extended African rift valley. A rift valley is a valley that is created by the splitting of the earth’s crust. Two major rift valleys occur on the land surface, or in the continental crust: the Baikal Rift Valley in Siberia and the African Rift. The East African rift valley is mainly created by the separating of the Nubian plate and the Somalian Plate, which together comprise the African plate of the African continent.
The East African Rift valley developing during the Miocene that is 22-25 Million years ago and stretches thousands of kilometers across, Eritrea, Ethiopia, Kenya, Uganda, Rwanda, Burundi, Zambia, Tanzania, Malawi, and Mozambique.
As part of the northernmost end part of the rift valley, the land of Eritrea has contributed unparalleled evidence related to the evolution of our ancestors and other mammals. The now inhospitable place of Danakil Depression of Eritrea was home to our ancestors about 1.0 million years before present.
The Eritrean Danakil Depression which is part of the vast Depression of the Danakil located at the intersection of the Red Sea, the Gulf of Aden and the East African Rifts was Home to our human ancestors and different animals dated to about 1.0 million years ago.
More than two decades of fieldwork at the Eritrean Danakil depression resulted with a discovery of over 200 sites within about 1000 meters thick sedimentary succession, which is so unique in the African context. The sedimentary deposits that preserve the fossil specimens of our human ancestors and the large mammalian fauna are dated to around 1.0 million years before present. Amongst these the most prominent localities include: Maebele, Dioli, Aalad, Aalad-Amo, Mulhuli-Amo…etc. These are the most prominent localities with the evidence of well-preserved fossils of humans in association with stone tools and large mammals.
The discovery of the almost complete human skull (~1.0 million years old) from Aalad (also called Homo-site) was exceptionally a scientific breakthrough. This cranium is attributed to a female individual, and researchers nicknamed her, “the Lady of Buia”.
While some others like to call her “Eve” as it is the first female discovery in the region. Therefore, in this paper, “the Lady of Buia” refers to the woman with the age of about 24 – 28 years, found near the village of Buia (in Eritrea) in 1995 and having an age of about one million years. This is the first ever evidence related to our direct ancestors from a place just about 31 km far from the Gulf of Zula.
In association, to the Buia skull, two teeth and fragments of a pelvis were found. According to anthropologists, Buia skull is the first intact hominin skull found from the period between 1.4 million and 650,000 years ago. So far, this is the earliest known appearance of an individual with Homo sapiens traits.
To date, evidence of a complete skull of Homo between 1.4 million years to 650,000 years is scarce in Africa. This unique fossil finding from Buia filled the gap between Homo erectus and Homo heidelbergensis. The original fossil find is housed in the National Museum of Eritrea.
The lady of Buia presents both typical Homo erectus and Homo sapiens characters. It blends features of Homo erectus- a tool-using hominid predating modern humans – with those of Homo sapiens. This has given birth to some new hypotheses that would move back the appearance of the sapiens species back in time.
The lady of Buia skull has interesting features and these include; massive brow-ridges which is a long and oval shape and pointed at the back and relatively small brain capacity. All these are typical characteristic features of Homo erectus. Where the skull differs from Homo erectus is in the parietal bones, which form the curved sides and top of the skull. They are much wider at the top than those of Homo erectus and are typical of Homo sapiens.
From an anthropological point of view, these characteristic features mark to the exceptional position of the lady of Buia in Human evolution research; which has paramount importance and contribution in understanding the evolutionary account of humanity.
The huge accumulation of stone tool artifacts found in Buia today shows that the lady of Buia was an efficient hunter and was responsible for the accumulation of all the dismembered bones found in Buia today. Not only this, this exceptionally and huge accumulation of stone tools show the human technological thrive in the area and existing competition with other carnivores. This hypothesis is evident referring to the association of the fossil remains of the terrestrial vertebrates – elephants, hippopotamus, hyenas, pigs, rhinos, … etc – to the Buia Lady skull.
The Buia basin has also great significance in understanding mammalian diversification, turnover, dispersal, and extinction. The animals surviving to the present day are evident testimonies of the long and harsh evolutionary process. This mammal evidence is found at the same geological layer formed in the fluvial-lacustrine environment. Based on paleo-environmental studies the Buia basin was a savanna with wide green spaces, streams, ponds, and lakes. It is quite different from the harsh environment of the present day.
The most interesting of all is what the cranium of the lady of Buia tells us of our own evolution. Prior to this find, the earliest fossils with Homo sapiens features date to a mere 700,000 to 600,000 years ago. The age of this skull indicates that morphology like that of Homo sapiens had begun to differentiate in Africa 1 million years ago, which is 300,000 years earlier than previously estimated. Hence, she is the oldest direct ancestor of to the only and existing Human species populating the earth.
In this context, the lady of Buia is proving the need to appreciate our origin and harmony regardless of our present-day diversity. The Eritrean society owns incredible prehistory that goes back to the origin of humanity. That is a base to the present-day social make and diversity. Regardless of the social dynamism and cultural evolutions that follows we all are children of the lady of Buia. She is Eritrea’s paramount evidence for our founding identity, unity, and development.
TSEGAI MEDIN (PhD) is a researcher at the Institut Català de Paleoecologia Humana i Evolució Social