Dmanisi Hominid Archaeological Site

Description

Recent excavations of Dmanisi have revealed an extraordinary record of the earliest hominid dispersal beyond Africa (1,75 million years ago). Several hominid individuals along with abundant well-preserved remains of fossil animals and stone artefacts have been found. The Dmanisi specimens are the most primitive and small-brained humans found outside of Africa to be attributed to Homo erectus sensu lato, and they are the closest to the presumed Homo habilis-like stream. It is widely recognized that Dmanisi discoveries have changed scientist's knowledge concerning the migration of homo from Africa to the European continent.

Dmanisi is located about 85 km south-west of Tbilisi buried below the ruins of the medieval town of Dmanisi, in the Mashavera River Valley, which drains the Javakheti volcanic chain to the west of the site. The site is situated on a promontory elevated about 80 m above the confluence of the Mashavera and Pinezaouri River valleys. Just prior to the occupations at Dmanisi, the Mashavera Valley was filled by 80-100 m of mafic lavas that formed the Mashavera Basalt. This basalt dammed the Pinezaouri Valley, forming a lake ca. 1 km long immediately south of the site.

The hominid and artefact-bearing deposits (up to 3 m thick) directly cover the original surface of basalt layer (Mashavera basalt) and are magnetically normal, dated ca. 1.8±0.01 Ma and correlated with Olduvai subchron. No evidence of erosion and minimal weathering of its surface suggest that the basalt was quickly buried by volcanic ash and fossiliferous sediments.

Presently two main stratigraphic units are distinguished in the exposed sections:

• Stratum A, bearing vast majority of the faunal materials and all hominid remains - consisting of pyroclastic silt and fine sand with weak pedogenic structure and pedogenic carbonates in the upper part.
• Stratum B, with highest densities of stone artefacts but poorer with fossils - consisting of weathered volcanic silts and sands, with dark grey ash in the middle of the unit and prominent basal grey ash.

These two layers are separated by calcareous horizon that has halted further diagenetic damage and compaction in stratum A thus allowing remarkable fossil preservation. The structure and thickness of calcareous horizon is variable in different locations and is posing questions concerning sedimentation process that need to be clarified.

Central geographic location, dramatic biodiversity, and the extremely dynamic geologic evolution of the Caucasus region on the Neogene-Quaternary boundary, permits to generate not only new geologic information, but also new protocols for expanding stratigraphic studies and archaeological site surveys by teams working in the important adjacent regions of the Levant, south-eastern Europe, and south-central Asia.

Dmanisi archaeological material is well dated by science-based methods to about 1.75 million years ago. The Lower Palaeolithic site has the fascinating and unusual context of being located underneath the medieval ruins of an ancient town and fortress frequently visited by tourists. In fact, the Palaeolithic excavations have all been conducted from within the walls of ancient structures. From point of view of the early palaeontology, the site has been known since 1983 when fossilized bones of extinct animals were found by medieval archaeologists in the walls of household pits of the Dmanisi medieval town. Immediately, it was clear that we were dealing with late-middle Villafranchian fauna, of approximately 1.8-1.7 million years in age. Then in 1984, with the discovery of primitive stone tools, a new page started not only in the history of the site excavations, but of one of the major events in human evolution: the peopling of the northern latitudes and eventually the entire globe. Dmanisi is the key to deciphering Homo's origins and for tracing the earliest Pleistocene hominid migrations. Dmanisi have an iconic position in the discovery and demonstration of human evolution.

Recent excavations of Dmanisi have revealed an extraordinary record of the earliest hominid dispersal beyond Africa. Several hominid individuals (4 skulls, 3 of them with maxillas, 4 mandibles, 16 isolated teeth and 24 post-cranial elements), along with abundant well-preserved remains of fossil animals and stone artefacts have been found. In 2003-04 field season another new hominid mandible, with fascinating pathologies having implications for the evolution of human disease and also social behaviour has been discovered. It was also found a new tibia and talus (ankle) bone, which will allow accurate estimations of body size, body proportions and locomotory behaviour. This is the richest and most complete collection of indisputable early Homo remains outside of Africa with good stratigraphic context, now well dated to about 1.75 million years ago. At Dmanisi, there is also clear potential to define and compare records of serial occupations in single locality.

Dmanisi discoveries are most ancient in whole Eurasia and are dated to 1.75 million years ago. There is the great potential for further finds as well.

Déclarations d’authenticité et/ou d’intégrité

The palaeoarchaeological site of Dmanisi is completely authentic: several hominid individuals along with abundant remains of fossil animals and stone artefacts are well-preserved and there is no evidence of erosion and minimal weathering of hominid and artefact-bearing deposits surface.

Comparaison avec d’autres biens similaires

Dmanisi corresponds to all criteria defined in the ICOMOS comparative study for Hominid sites: good chronologies; number of fossils; antiquity of finds; potential for further finds; groups of closely related sites; and discovery and demonstration of human evolution. ICOMOS study divides human evolution into four periods, the earliest of which is from 5 million to 1 million years BP. Among Hominid sites on the World Heritage List Dmanisi can be compared with the Atapuerca Archaeological Site in Spain and Sterkfontein Valley in South Africa. The earliest Hominid remains in Atapuerca are dated from circa 800 000 BP, while Dmanisi specimens are dated to 1.75 million years ago. Thus, Dmanisi is the only European site belonging to the first period defined in ICOMOS study.