Melka Kunture and Balchit

Description

Melka Kunture, as it can be seen today, is part of a gently undulating landscape of the Upper Awash Valley, in the highlands of Ethiopia, at c. 2000m asl. All over the Upper Pliocene and the Pleistocene, tectonic activities led to the deepening of the demi-graben depression were the meandering paleo-Awash deposited alluvia. Through time, parts of the paleo-landscape were buried again and again, blanketed both by alluvial deposits, and by volcanic deposits produced by the nearby volcanoes. Accordingly, past surfaces, littered with archaeological implement and prehistoric animal remains, were covered by sediments and escaped destruction. They are now evidenced by natural erosion on the banks of the little gullies of the local tributaries of the Awash.

Archaeological excavations allowed for the recovery of the prehistoric heritage and of related scientific information. More than 80 archaeological layers have been identified during 50 years of archaeological research; 30 of them have been extensively excavated over surfaces ranging from 50m² to 250m². Tens of thousands of lithic tools, faunal and sometime human remains (Homo erectus sensu lato and archaic Homo sapiens) have been discovered. Many more are preserved in an area of more than 100 km², and wait for future research and for future generations of scholars.

The visible thickness of these deposits is around 30 m, but the cumulative thickness of the various levels is about 100 m. The archaeological deposits of Melka Kunture are a unique archive of human evolution, spanning over more than 1.7 million years, from Oldowan layers, to a very long and complex sequence of Acheulean layers, to Middle Stone Age and eventually by Late Stone Age layers. All over this sequence, a diversified range of lithic raw materials of volcanic origin were available for knapping by humans: each had different properties and qualities, all were carefully tested and, when found suitable, eventually exploited. The volcanic rocks utilized for knapping were different types of basalts, ignimbrites, trachytes and trachybasalts on one hand, and obsidian on the other hand. These two groups of raw materials present completely different qualities for stone knapping. Accordingly, Melka Kunture can be seen as a laboratory for human evolution, where the requisites for trial and error procedures were naturally available, fostering the development of cognitive capabilities in humans.

Obsidian is specially important, and appears at virtually each site, starting in the archaeological record with the Oldowan at 1.7 million years. At some sites obsidian is the only material used. The primary source is Balchit, a dome-flow which is also part of the archaeological area. Erosion of the Balchit outcrops and redeposition by the tributaries of the Awash eventually led to the formation of rich and numerous secondary sources, which did not escape the attention of prehistoric humans. Obsidian exploitation was still under way in recent historic times, when this naturally occurring volcanic glass was used in every day activities, as in curing animal hides. The obsidian dome-flow of Balchit is spotted by extensive flaking areas. Cores, flakes, blades and debris have accumulated on thousands of square meters since prehistory and well into historic times.

Justification of Outstanding Universal Value

Criterion (iii): The archaeological record of Melka Kunture spans over 1.7 million years, and ends in historic times. Prehistoric human groups made a living out of natural resources, both in terms of vegetables, which rarely survive, and in terms of wild animal resources, which left ample archaeological evidence. Obsidian and other locally available volcanic rocks were knapped and used to prepare implements. Lithic implements littered past landscapes are retrieved from scientific excavations, allowing to reconstruct prehistoric human activity. The success history of human evolution and adaptations which shaped modern humankind is beautifully evidenced at the many archaeological sites. Thanks to sedimentary processes which allowed preservation, there is a continuous record over the Middle and Upper Pleistocene. Such a preservation is exceptional, and documents through an extremely long span of time the ways of life of little nomadic human groups.

Criterion (iv): Paleo-landscapes rarely survive erosion, and when existing are often hidden by a load sediments deposited after they were not any more in existence. In the case of Melka Kunture, there was a subtle balance of processes leading to preservation and destruction, and fragments of very ancient, fossil landscapes are evidenced by ongoing, if limited erosion in the gullies of the Awash tributaries. Visibility, in turn, allows scientific research and the reconstruction of past events. But the whole area is better described as a palimpsest of superimposed fragments of fossil paleo-landscapes, on top of which rural activity nowadays goes on. Melka Kunture is a repository and archive of well preserved fragments of landscapes of Pleistocene age, which include great amounts of archaeological remains documenting the environment and ways of life of prehistoric human groups.

There is also evidence of the development of a very special landscape at Balchit, up to very recent times. Due to the continuous exploitation of the obsidian dome-flow to produce cutting and scraping implements, the modern landscape of the area is littered by millions of flakes, blades, cores and debris, which accumulated in late prehistoric and historic times. Heaps of by-products of obsidian knapping activities alternate with natural exposures, and with glittering stretches of land. This is an impressive sight over thousands of square meters, where randomly abandoned volcanic-glass implements reflect the light of the sun. The relationship between modern human groups and obsidian sources is in full sight.

Criterion (v): Most of the archaeological evidence of Melka Kunture belongs to times when neither farming nor herding was practiced. Humans belonging both to Homo erectus (sensu lato) and, later, to Homo sapiens were invariably organised in little groups, which walked from place to place to make full use of naturally available resources. The latter ones were closely monitored, when occurring seasonally, as vegetable and animal resources; and systematically tested, when locally outcropping, as rocks suitable for knapping. The building-up of a vast knowledge of the qualities and potential use of any kind of naturally occurring resources is reflected by the successful and long-term adaptation to the highlands of Ethiopia. This, in turn, is fully evidenced in the very long archaeological record of Melka Kunture, over 1,7 million years.

Criterion (viii): The highlands of Ethiopia, 1500m to 4500m asl, are close to the equator but enjoy a temperate climate because of the altitude. Melka Kunture, at 2000-2200m asl, with its extremely long fossil record, allows understanding the development through time of the distinctive Afromontane fauna and flora of the Ethiopian highlands. The multiple fragments of Pleistocene paleo-landscapes buried and preserved below volcanic and sedimentary deposits provide an exceptional window to understand past association of surviving and extinct species, including hominin ones, as well as the development of botanical associations.

All the archaeological sites of Melka Kunture yield vertebrate fossils and a few invertebrates in addition to the prehistoric artefacts, the richest fossil sites being Garba IV, Gombore I and Gombore II, dating back from 1. 7 to 0. 7 million years ago. Overall, the animal species remind of those of the present-day African savannahs, but with some special characters. The hippopotamus is by far the most common animal and mostly belongs to a form close to the modern East African hippo. However, the species found up to 0.8 million years ago have teeth that are less high than those of the modern form, suggesting a less abrasive diet, an adaptation unknown elsewhere in Ethiopia at that period. Some of the mammal species are new and not found anywhere else. This is the case of Damaliscus strepsiceras, with spiraled horns as well as of a wildebeest, Connochaetes gentryi leptoceras, with very long, slender horns very different from those of its modern relative. An extinct equid of the three-toed genus Hipparion persists here until about 0.7 Ma, thus later than elsewhere. These differences point to some isolation of the Ethiopian highlands at that time, and Melka Kunture is one of the very few sites that document this biogeographic distinction. This points towards an isolation of some part of the Ethiopian highlands during parts of the Pleistocene, when mammal faunas were evolving.

The preservation of fossil pollen allowed palynological analysis and a detailed reconstruction of past vegetation. At 1.7 million years ago, when early hominids settled at Melka Kunture with an Oldowan lithic industry, the vegetation was already rather similar to the modern "Dry evergreen Afromontane forest and grassland complex", currently covering the highlands of Ethiopia between 1800m and 3000m asl. This vegetation remained of the same mountain character afterwards, even if fluctuations between low and high tree cover densities have been evidenced.

Melka Kunture also is one of the earliest evidence of human occupation of high altitudes, and accordingly hominids are part of this landscape with mountain vegetation. Long before any evidence of fire domestication, early hominids of the Melka Kunture region had already adapted to mountain tropical climatic conditions, including great daily temperature range between days and nights, as well as some uncommon animal species. Accordingly, the record provides unprecedented evidence of flexibility and adaptability since an early stage of human evolution.

Statements of authenticity and/or integrity

Melka Kunture has been the focus of long-term archaeological, palaeontological, and geological research over the last 50 years. The results have been disseminated in the scientific community following the standard procedures of participation to international congresses; publication in scientific journals of recognized reputation; publication of a comprehensive monograph; publication online. The wealth of accumulated information has been used for the "Description" and "Justification of Outstanding Universal Value", which are fully supported by scientific evidence properly published and made available in approximately 100 scientific papers. This includes the age of the deposits, the determination of the human remains, the determination of the fossil animal species, the analysis of the technical achievements of prehistoric human groups, as reflected m the archaeological record, the reconstruction of the general environment.

The collections made during the many excavation campaign are kept and curated at the National Museum in Addis Ababa, where they are available for further scientific analysis.

Outside the scientific circles, the information has been disseminated to a wide public, which can visit the website, as well as the museum built in the archaeological area.

Comparison with other similar properties

Archaeological and paleontological properties or sites with long stratigraphic sequences related to the earliest developments of humankind exist in Ethiopia and elsewhere.The Lower Valley of the Awash in Ethiopia is characterized by fossiliferous deposits of Miocene age, including the well-known find spot of "Lucy", 3.2 million years old. The many remains which have been discovered allow to traces early stages of hominin evolution.

The Lower Valley of the Omo in Ethiopia, including Lake Turkana, is also characterized by fossiliferous deposits bearing hominin remains, later in age if compared to those of the Lower Awash Valley. There is also some of the earliest evidence of lithic industries, with archaeological sites dating back to 2-2.3 million years.

Olduvai Gorge, in the Ngorongoro Conservation Area of Tanzania, is where Louis and Mary Leakey first discovered Homo habilis. There is a very long archaeological sequence, as in Melka Kunture. Much of the efforts and attention have been for the sites in Bed I and Bed II, with Oldowan and Acheulean layers, between 1.85 and 1.2 million years ago. The sediments overlying Beds I and II date to between 1.2 million years ago and 60,000-40,000 years ago. Comparisons can also be established with the archaeological record of the Nachukui Formation, a PlioPleistocene sedimentary Formation located in the northern part of Kenya, west of lake Turkana. The geological sequence offers a set of Oldowan and Acheulean sites, aged between 2.34 and 0.70 million years.

Broadly comparable depositional sequences also exist outside Africa in the Jordan Valley of Israel, where two multi-layered site, Ubadiyya (Ubeidiya) and Gesher Benot Ya'akov date back to 1.4 and 0.8 million years respectively. Rich assemblages were unearthed, while human remains were not discovered.

The archaeological and palaeontological evidence embedded in the area of Melka Kunture refers to a time-range when the capability of producing stone tools was fully developed, i.e. it is later than in the Lower Awash Valley and in the Lower Omo Valley. It is better compared to the sequences of Olduvai and of the Nachukui Formation, and to the record from the Jordan Valley. It differs from all of them for the very high density of archaeological, multi-layered sites, at a few km from each other; for the adaptation to a different natural environment, where elephants, a prominent part of African past and present landscapes, were notably absent; for the early exploitation of obsidian, a raw material with specific knapping qualities which was used at a much larger scale than at any other site of Middle Pleistocene age; for the positive evidence of continuity between Homo erectus and Homo sapiens, seen in remains of a 1.5 million years Homo erectus child which suffered of amelogenesis imperfecta, a genetically-controlled disorder still existing today; for the rich record of obsidian use up to historic times, in the area close to the obsidian outcrop of Balchit.