Located under the visible remains of a medieval fortress, the Dmanisi excavation (right) has yielded artifacts from several eras of human occupation, with older material particularly well preserved under more recent volcanic deposits. Within these layers, archaeologists in 1991 discovered the oldest hominin fossil outside Africa: a 1.77-million-year-old jaw bone belonging to Homo erectus. Skulls and long bones found since then have allowed scientists to build a picture of the small, mobile human relatives living at Dmanisi. Now, interpretive analyses at the site are adding to the understanding of early human migration, adaptations, and behavior, said paleoanthropologist David Lordkipanidze, director of the Georgian National Museum, who coordinates work at Dmanisi.
“In Dmanisi, [early humans] are very well adapted to the environment,” Lordkipanidze says. “They had exactly enough brain capacity, exactly the anatomy and features to be adaptive, and the capacity to produce stone tools.”
Ferring’s work represents just one facet of ongoing efforts to interpret the finds at Dmanisi, which Harvard University archaeologist and curator Ofer Bar-Yosef likens to a paleolithic bus station. “People come to it and then spread into Eurasia, some go to Europe, some go to other parts of Asia,” says Bar-Yosef, who was not involved in Ferring’s work. He says the idea that the stones were used for driving off carnivores is compelling, but adds that there may have been other reasons why the stones were brought there. “My suggestion is that some of the stones were used to pound meat,” he says, an essential activity prior to the use of fire for cooking flesh.
Ferring agrees, explaining that the larger rocks at the site were likely tools used for pounding flesh, cutting meat, or smashing bones – but that the smaller stones might have served a different purpose: aiding in aggressive scavenging and tipping the scales toward success for the “small, first colonists of Eurasia.”
Since its discovery, Dmanisi has provided a crucial signpost for dating the human exodus from Africa. More recent work by Ferring and others now suggests the site can shed light on early social behavior and adaptations among human ancestors.
“More and more, colleagues are interested in adaptation, behaviour, social organization, evolution of the social brain,” says Bar-Yosef. “But the essentials – chronology, detailed information from the sites –- are critical if we are to evaluate or reconstruct how these hominins adapted themselves to environments entirely different from the African savanna."
Ferring says he and his colleagues will continue building the case for early stone-throwing at Dmanisi by excavating additional areas at the site – away from the gullies – and tracking associations between cobbles, flaked stones, and bones. Ferring hopes the site will answer questions about how Homo erectus found food, a missing piece in the picture of early human adaptations and behaviors. “It’s a tough nut to crack,” he says. “But Dmanisi provides us with one of the strongest chances to look at context that has ever been recovered.”
Posted by Ivan Semeniuk on April 11, 2011
http://blogs.nature.com/news/thegreatbeyond/2011/04/was_eurasia_a_stones_throw_for.html