Next week at New York City’s American Museum of Natural History, an international team of scientists will unveil a complete, 47-million year old fossil found in Germany that may be one of the most important anthropological discoveries ever made: a primate creature that could be the common ancestor of all monkeys, apes, and humans.

Anthropologists have long believed that humans evolved from ancient ape-like ancestors. Some 50 million years ago, two ape-like groups walked the Earth. One is known as the tarsidae, a precursor of the tarsier, a tiny, large-eyed creature that lives in Asia. Another group is known as the adapidae, a precursor of today’s lemurs in Madagascar.

Based on previously limited fossil evidence, one big debate had been whether the tarsidae or adapidae group gave rise to monkeys, apes and humans. The latest discovery bolsters the less common position that our ancient ape-like ancestor was an adapid, the believed precursor of lemurs.

Philip Gingerich, president-elect of the Paleontological Society in the U.S., has co-written a paper that will detail next week the latest fossil discovery in Public Library of Science, a peer-reviewed, online journal.

“This discovery brings a forgotten group into focus as a possible ancestor of higher primates,” Mr. Gingerich, a professor of paleontology at the University of Michigan, said in an interview.