Washington, March 3 (ANI): New research work by scientists has indicated that a fossil that was celebrated last year as a possible "missing link" between humans and early primates is actually a forebearer of modern-day lemurs and lorises.
Four scientists present evidence that the 47-million-year-old Darwinius masillae is not a haplorhine primate like humans, apes and monkeys, as the 2009 research claimed.
They also note that the article on Darwinius published last year in the journal PLoS ONE ignores two decades of published research showing that similar fossils are actually strepsirrhines, the primate group that includes lemurs and lorises.
"Many lines of evidence indicate that Darwinius has nothing at all to do with human evolution," said Chris Kirk, associate professor of anthropology at The University of Texas at Austin.
"Every year, scientists describe new fossils that contribute to our understanding of primate evolution. What's amazing about Darwinius is, despite the fact that it's nearly complete, it tells us very little that we didn't already know from fossils of closely related species," he added.
Last spring's much-publicized article on Darwinius was released in conjunction with a book, a History Channel documentary, and an exhibit in the American Museum of Natural History.
"Just because it's a complete and well-preserved fossil doesn't mean it's going to overthrow all our ideas," said anthropologist Blythe Williams, the lead author.
The scientists who last year formally described Darwinius concluded that it was an early haplorhine, and even suggested that Darwinius and other adapiform fossils "could represent a stem group from which later anthropoid primates evolved."
For example, they note that Darwinius has a short snout and a deep jaw - two features that are found in monkeys, apes, and humans.
However, Kirk, Williams and their colleagues point out that short snouts and deep jaws are known to have evolved multiple times among primates, including several times within the lemur/loris lineage.
They further argue that Darwinius lacks most of the key anatomical features that could demonstrate a close evolutionary relationship with living haplorhines (apes, monkeys, humans, and tarsiers).
For instance, haplorhines have a middle ear with two chambers and a plate of bone that shields the eyes from the chewing muscles.
"There is no evidence that Darwinius shared these features with living haplorhines," said Kirk. "And if you can't even make that case, you can forget about Darwinius being a close relative of humans or other anthropoids," he added. (ANI)