| Sergei Davydov, a specialist in ancient ecosystems, holds the thigh bone of a mammoth as he stands next to a table with pre-historic bones exposed by melting permafrost in Chersky, in northeast Siberia, Aug. 29, 2007. In Siberia’s northernmost reaches, high up in the Arctic Circle, the changing temperature is thawing out the permafrost to reveal the bones of prehistoric animals like mammoths, woolly rhinos and lions that have been buried for thousands of years. |
