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May 16, 2009
German Fossil Found to Be Early Primate
By JOHN NOBLE WILFORD
Fossil remains of a 47-million-year-old animal, found years ago in Germany, have been analyzed more thoroughly and determined to be an extremely early primate close to the emergence of the evolutionary branch leading to monkeys, apes and humans, scientists said in interviews this week.
Described as the “most complete fossil primate ever discovered,” the specimen is a juvenile female the size of a small monkey. Only the left lower limb is missing, and the preservation is so remarkable that impressions of fur and the soft body outline are still clear. The animal’s last meal, of fruit and leaves, remained in the stomach cavity.
In an article to be published on Tuesday in PLoS One, an online scientific journal, an international team of scientists will report that this extraordinary fossil could be a “stem group” from which higher primates evolved, “but we are not advocating this.”
The researchers said the specimen, designated Darwinius masillae, “is important in being exceptionally well preserved and providing a much more complete understanding of the paleobiology” of a primate from the Eocene period, a time when primitive primates were starting to branch into two lineages, the prosimians and the anthropoids.
As part of a heavily promoted publicity campaign, the skeleton will be displayed at a news conference on Tuesday at the American Museum of Natural History in New York; the History Channel plans a documentary on the primate at 9 p.m. on May 25; and Little Brown is bringing out a book. The Wall Street Journal published an article on Friday giving some scientific details of the discovery.
The specimen was excavated by private collectors in 1983 from the Messel Shale Pit, a shale quarry near Darmstadt, Germany, that has yielded many fossils of Eocene life, including other primitive primates.
Jörn H. Hurum, a paleontologist at the University of Oslo and a leader of the research, said the site was “one of the real treasure troves of paleontology, like the Gobi Desert for dinosaurs.”
The skeleton was divided and sold in two parts, one of which had dropped out of sight. When Dr. Hurum learned that the missing part was for sale, he arranged for its purchase by the Natural History Museum in Oslo and two years ago rounded up a team of German and American scientists to study the bones with CT imaging and other advanced technologies.
Speaking by telephone from Norway, Dr. Hurum recalled: “I realized at first it’s a primate. It just screams primate: opposable big toes and thumbs, no evidence of claws. This is like the Archaeopteryx of primate evolution.”
The scientists estimated that the primate was about 9 months old, the equivalent of a 6-year-old human. At maturity they suggest that it would have weighed two pounds and been two feet long, most of it tail. It had a broken left wrist, healing at the time of death, and may have drowned in the volcanic lake at Messel. It was, the researchers said, something like a combination “lemur monkey.”
Philip D. Gingerich, a member of the team who is a paleontologist of Eocene life at the University of Michigan, said in an e-mail message that in the context of other fossil finds and DNA studies the primate should be considered for a place in the ancestral line leading to living higher primates, including apes and humans. "