Researchers have located chemical remains of the oldest known bird from fossils recovered 150 years ago, a new study claims.
The discovery of the Archaeopteryx feathers appears this week in the journal Proceedings of the National Academy of Sciences.
The researchers say the sample contains "portions of the feathers are not merely impressions of long-decomposed organic material as was previously believed".
"Instead, they include fossilised fragments of actual feathers containing phosphorous and sulfur, elements that compose modern bird feathers," write researchers led by geochemist Dr Roy Wogelius of the University of Manchester.
"We talk about the physical link between birds and dinosaurs, and now we have found a chemical link between them," says Wogelius.
"In the fields of palaeontology and geology, people have studied bones for decades. But this whole idea of the preservation of trace metals and the chemical remains of soft tissue is quite exciting."
British and US researchers found that trace amounts of copper and zinc were also found in the 'dino-bird' bones: like modern birds, the Archaeopteryx may have needed them to flourish.
"Archaeopteryx is to palaeontology what Tutankhamen is to archaeology. It's simply one of the icons of our field," says University of Manchester palaeontologist Dr Phil Manning.
"You would think after 150 years of study, we'd know everything we need to know about this animal. But guess what, we were wrong."
Wogelius says, "We talk about the physical link between birds and dinosaurs, and now we have found a chemical link between them.
Researchers made the game-changing discovery by subjecting the Archaepteryx fossil to super-strong x-rays at the Stanford Synchrotron Radiation Lightsource (SSRL) in California.
Dr Uwe Bergmann, who led the x-ray scanning experiment, says, "People have never used a technique this sensitive on Archaeopteryx before.
"Because the SSRL beam is so bright, we were able to see the teeniest chemical traces that nobody thought were there."
CMW Institute researcher Bob Morton says, "The discovery that certain fossils retain the detailed chemistry of the original organisms offers scientists a new avenue for learning about long-extinct creatures."