By Will Dunham

WASHINGTON, Aug 10 (Reuters) - Researchers applying modern forensic techniques to a century-old puzzle have laid bare intriguing new details about one of the most notorious scientific hoaxes on record, the so-called Piltdown Man, and are confident in the culprit's identity.

The phony fossil remains of a "missing link" between apes and humans, planted in gravel near the English village of Piltdown, were concocted using the jawbone and teeth from a single orangutan, two or three sets of old human remains and the liberal use of dental putty, the researchers said on Wednesday.

They said their findings left little doubt the perpetrator was amateur archaeologist Charles Dawson, who in 1912 "discovered" the first of the bogus Piltdown remains and has long been the chief suspect.

The study, using DNA analyses, high-precision measurements, spectroscopy and other techniques, was published in the journal Royal Society Open Science on the 100th anniversary of Dawson's death.

"This is a fascinating real-life 'whodunit' and it shows how new technology can be applied to solve old problems," said paleoanthropologist Chris Stringer of the Natural History Museum in London.

The Piltdown remains created a scientific sensation as the long-awaited "missing link" confirming Charles Darwin's evolution theory. Four decades passed before it was proven as a hoax.

"It set back studies of human evolution for many years, particularly in Britain, as some of the most prominent experts allowed themselves to be misled," Stringer said.

DNA analysis showed the original "discovery" and a second set of remains announced by Dawson included teeth, filed down to make them appear human, and a lower jaw from a single orangutan, mostly likely from southwestern Sarawak, Borneo.

Remains from two or perhaps three possibly medieval humans were used to make up the forged cranial fossils, using the same part of the back of the skull, anthropologist Isabelle De Groote of Liverpool John Moores University said.

Skull holes were filled with putty, which also was employed to reset the teeth in the jaw and reconstruct one of the teeth.

The fact a single orangutan specimen was used in both sets of remains implicates Dawson, the only person associated with both, Stringer said. There was also a consistent modus operandi in the concoction of the two sets, indicating a single forger, Stringer said.

Experts suspect Dawson's motives were winning fame and recognition from the scientific community. A recent analysis of Dawson's collection of fossils and antiques revealed other forgeries.

(Reporting by Will Dunham in Washington; Editing by Sandra Maler) ((; 1 202 898 8300; Reuters Messaging: