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Another hominid skull has been recovered at Dmanisi (Republic of Georgia) from the same strata in which hominid remains have been reported previously. The Dmanisi site dated to ~1.75 million years ago has now produced craniofacial portions of several hominid individuals, along with many well-preserved animal fossils and quantities of stone artifacts. Although there are certain anatomical differences among the Dmanisi specimens, the hominids do not clearly represent more than one taxon. We assign the new skull provisionally to Homo erectus (=ergaster). The Dmanisi specimens are the most primitive and small-brained fossils to be grouped with this species or any taxon linked unequivocally with genus Homo and also the ones most similar to the presumed habilis-like stem. We suggest that the ancestors of the Dmanisi population dispersed from Africa before the emergence of humans identified broadly with the H. erectus grade.
The new Dmanisi cranium (D2700) and associated mandible (D2735) were found in squares 60/65 and 60/66 (Fig. 1), embedded in the black to dark-brown tuffaceous sand immediately overlying the 1.85-million-year-- old Masavera Basalt. Sedimentary horizons above the basalt also yielded two partial crania in 1999, along with mandibles discovered in 1991 and 2000 (1-7). The new hominid remains were associated with animal fossils that include an entire skull of Stephanorhinus etruscus etruscus, a skull of Cervus perrieri with a full rack of antlers, a Dama nesti antler, two crania of Canis etruscus, a complete mandible of Equus stenonis, and the anterior portion of a Megantereon cranium. Human occupation at Dmanisi is correlated to the terminal part of the (magnetically normal) Olduvai Subchron and immediately overlying (magnetically reversed) horizons of the Matuyama Chron, and is ~1.75 million years in age (5, 6, 8). Faunal remains also support the dating of Dmanisi to the end of the Pliocene or earliest Pleistocene (8, 9).
The evidence suggests that much of the Dmanisi fauna was buried rapidly after death, in many cases with ligaments still attached, and that the bones were buried very gently, with minimal transport. The protection afforded the bones in lower layers by the overlying calcareous horizon halted further diagenetic damage and compaction that normally occur. Sedimentological information and the appearance of all the fossils found nearby reinforce the conclusion that the hominid and...