Scientists unveiled on Tuesday a 47-million-year-old primate fossil whose physical features, they believe, make it part of the common ancestry of all apes and humans.
Uncovered in Germany 26 years ago by private collectors who split and sold the two halves, the fossil has been reassembled by a team led by Norwegian fossil expert Jorn Hurum. Their findings were published Tuesday online in the Public Library of Science (PLoS).
With uncustomary hoopla for a scientific find, New York Mayor Michael Bloomberg attended the unveiling at the city's Natural History Museum, part of a publicity-building event before a film about the discovery is to air on Monday, a public US holiday, on the History Channel.
The University of Oslo said in a press release that Hurum's team of scientists has been studying for the past two years in great secrecy to complete a forensic analysis of the fossil, which was named Ida, after Hurum's daughter.
The fossil represents a new species of primates which lived in the forests of central Europe, and is "extraordinary" for its completeness, including "an entire soft body outline ... as well as contents of the digestive tract," the scientists wrote in PLoS.
Ida - its scientific name is Darwinius masillae - was acquired by Hurum in 2006 at the annual Hamburg Fossil and Mineral Fair in Germany. Ida, a young female in her first year of life, measures about 20 centimetres, and may have reached an adult weight of 600 to 900 grams.
Despite the collossal significance now accorded the fossil, it hung on the wall of the first owner for more than 20 years after it was discovered at Germany's Messel Shale pit near Frankfurt, famous for its trove of fossils. The site is on UNESCO's World Heritage list.