NEW YORK • A 47 million-year-old primate fossil that is so complete that scientists can even tell what its last meal was promises to shed new light on the earliest stages of evolution of the lineage that eventually led to humans, researchers said Tuesday.

The unprecedented new fossil of a lemurlike creature that probably weighed no more than 2 pounds when it was fully grown is remarkable because it is the most complete primate specimen ever obtained.

For the most part, the story of primate evolution has been pieced together from fossilized skulls, jawbones and the occasional foot - leaving large gaps in anatomy for researchers to fill in with informed speculation.

"This fossil is so complete, it is unheard of in the primate record," said paleontologist Jorn H. Hurum of the University of Oslo in Norway. "You have to get to a human burial to see something this complete."

Hurum is the lead author of a report that appeared Tuesday in the online journal PLoS One as part of a massive publicity campaign.

The information about the primate was revealed at a news conference at the American Museum of Natural History in New York, where a replica of the fossil is now on display.

A book about the discovery, called "The Link," will be published today by Little Brown and Co., and a documentary of the same name will be aired on the History Channel on Monday.

As is evident from the title of the book and documentary, the fossil is being promoted as a kind of "missing link" in the evolution of humans.

But the researchers themselves are more circumspect.

"It is a representative of an ancestral group giving rise of all kinds of higher primates," Hurum said. "We are not dealing with our great-great-great-grandmother, but perhaps our great-great-great-aunt."

Critics, however, say that it is not even that closely related.

"It's more like our third cousin twice removed," said paleontologist Chris Beard of the Carnegie Museum of Natural History at Johns Hopkins University. "It's part of the primate family tree that is about as far away from humans as you can get and still be a primate."

Regardless of the circuslike publicity and differing interpretations of researchers, the fossil itself is certainly a gem.

It is "the most completely preserved fossil primate that has ever been found," said paleontologist Tim White of the University of California, Berkeley, who was not involved in the research.

"It preserves things that are almost never preserved - stomach contents, tissues, hair. That only happens in very unique circumstances."

In this case, the unique circumstance is the Messel Shale Pit, a world-renowned source of fossils in Germany that is located about 25 miles southeast of Frankfurt.

Formed by a volcanic eruption nearly 48 million years ago, the shale in the pit has yielded a bounty of fossils from the Eocene epoch, when that region of Germany was a tropical forest.

Animals that fell into the volcanic lake sank to the bottom and lay virtually undisturbed until the present.

The cocktail of minerals in the water and sediment contributed to preservation.