At 2000m of altitude in Ethiopia, Melka Kunture provides a unique opportunity of understanding human evolution outside the savanna environments known elsewhere in Africa. Paleobotanical studies evidenced all over the Pleistocene mountains vegetation of the Dry evergreen afromontane forest and grassland complex. The rich archaeological sequence starts at 1.8 million years with the Oldowan, then the Acheulean, the Middle Stone Age and the Late Stone Age. Lithic raw materials, including obsidian, were abundantly available. The archaeological record also includes human and animal fossils, with footprints providing further direct evidence of animal and human life.
The ongoing project is aimed at: 1) defining into detail the environment, in order to better assess the limits of hominin adaptation to demanding conditions, with contrasted warm day temperatures and cold nights; 2) checking the evolving human capacities, through a techno-economic approach to well-dated lithic industries which takes into account the suitability and availability of raw materials; 3) re-assessing the taxonomic status of fossil hominin remains in relation with the lithic productions.
This year the focus will be on the Garba IV mandible, discovered in an Oldowan layer, published as of Homo erectus type. This is in contrast with the view that it was H. habilis who produced the Oldowan. The mandible was temporarily exported to Europe for micro-scanning, and this will allow a full re-assessment of the taxonomy. Fieldwork will be at Garba I Delta, a recently discovered layer of 1,300,000 years, a time so far poorly documented; at Simbiro III, more than 900,000 years old, with a unique specialization on obsidian use; and at Gombore II OAM, 850,000 years old, where ichnological excavations are planned. Communication and on line virtualization activities will be implemented in the framework of the candidature of Melka Kunture to Unesco's World Heritage List, as planned by the Ethiopian Authorities.
Melka Kunture is located at 2000m asl, at 8°N of the Equator, on the shoulder of the Main Erhiopian Rift. Paleobotanical analysis evidenced that Pleistocene vegetation was not of savanna-type, but belonged instead to the montane floristic domain ¿Dry Evergreen Afromontane Forest and Grassland Complex¿. Elsewhere in the Rift Valley at lower elevation, the climate all over the Pleistocene was much drier and hotter. Furthermore, in this volcanic area a number of different lithic raw materials were available to hominins, including obsidian largely in use ever since the Oldowan, 1,800,000 years ago. Hominin remains were discovered within well-excavated archaeological layers providing a firm association with lithic industries ¿ an information not available at many African sites. Recently, the excavations also revealed animal and human footprints, adding an ichnological record.
Accordingly Melka Kunture provides information not available elsewhere, which allow testing the characteristics, capabilities and adaptation capacities of the various hominin species.
The current research develops as follows:
- re-assessment of the hominin remains including: a) the stratigraphic sequences; b) the associated archaeological record; c) taphonomy; d) taxonomic status. The ongoing study of stratigraphic sequences and lithic industries is made clear in the section ¿Scientific Report for the last funding obtained¿. There is currently a focus on Garba IV juvenile mandible, from a 1,800,000 year-old layer. The taphonomy is studied by archaeozoologist Sabine Gaudzinksi; a permit was awarded for temporarily export for non-destructive analysis by high-resolution µCT, which was performed at the European Synchrotron Radiation Facility in Grenoble, France; the resulting high resolution micro-tomographic data are being elaborated by Adeline Le Cabec, combining techniques of 3D rendering and virtual paleohistology at the Max-Planck Institut in Leipzig, Germany, where comparative material is available. The outcome will be a full reassessment of the taxonomic status of the fossil, which could be either a Homo habilis, or a H. erectus sensu lato as mentioned so far in the literature. In the first case, H. habilis was the only maker of the Oldowan; in the second case, H. erectus produced not only Acheulean tools, as usually understood, but also Oldowan industries.
- testing hominin adaptation, a part of the project linked to the re-analysis of the hominin fossils. At 2000 m asl large diurnal temperature variations and nighttime frost may occur. If Garba IV was a H. habilis, this will be the first direct evidence that this species was able to adapt to the highlands. If not, H. erectus was the first expanding outside the savanna, with implications on the peopling of higher latitudes outside Africa, including Europe. Raw material availability and use is another aspect of adaptation to the local environment. The many different lithic resources, including obsidian, were differently exploited throughout the Pleistocene, as evidenced in published papers. The recent discovery of Garba I Delta, dated at c. 1,300,000 years, will allow investigating human capabilities and technological development in a time-period when there is a dearth of well-dated sites not just at Melka Kunture, but also in East Africa at large. The site and collections of Simbiro, predating 900.000 years, with Acheulean bifaces exclusively in obsidian, will also be under review.
- refining the environmental reconstruction. Footprints are a first-hand source to reconstruct past environments, but are quite rare in the Pleistocene record. This is the first time they are reported from Ethiopia. They provide direct evidence of the behavioral patterns of extinct species, including hominins, that happen to be underrepresented or not represented at all in the fossil record. The faunal record of Melka Kunture is always dominated by hippos, while many more species printed tracks. Accordingly ichnosurfaces allow producing a different picture of the prevailing animals in the general environment. Papers on the ichnosurfaces at Melka have been published or are under submission, but a larger record will be produced by the foreseen operation at Gombore II OAM.
To improve the communication of scientific discoveries at Melka Kunture we plan to make available to the scientific comunità a repository of data. As a first step, we will proceed with 3D re-elaborations of files produced by laser scanning during previous field seasons. We will also design a digitalized archive, which will supersede the present one, made of plans, maps, pictures etc. produced over the last 50 years. We will eventually also disseminate the results to a wider audience, through a communication plan that differentiates both horizontally and vertically: that is, adapting to the local public, as schoolchildren, and to the international one, i.e. tourists, through the main social media and diversified educational brochures.