Powerful X-ray reveals archaeopteryx feather’s hidden colors

A powerful X-ray machine, that shines a light brighter than the sun, has helped science detectives determine the color of a 150-million-year-old feather that once belonged to an archaeopteryx, an ancient animal that shared traits with both birds and dinosaurs.

In an article published in the Journal of Analytical Atomic Spectrometry, scientists say the archaeopteryx feather was patterned: light in color with a black tip, rather than all black, as previously thought.

The archaeopteryx, sometimes called a “dinobird,” is thought to be a transitional species between dinosaurs and birds. It has the feathered wings and wishbone of a bird, and the tail, teeth and heavy, slow-growing bones of a dinosaur.

Just 11 archaeopteryx fossils have been collected since the first one was discovered 150 years ago.

To discern the true colors of the dinobird’s plumage, the researchers scanned a well-preserved fossil of an archaeopteryx’s feather with the powerful synchrotron radiation light source at Stanford University. The synchrotron shone an X-ray light on the fossil brighter than a million suns, said Phil Manning of the University of Manchester, who led the study.

That blindingly bright light revealed chemical traces on the fossil that had been preserved for 150 million years, and those traces provided clues to the color of the prehistoric animal’s feathers.

Manning and his team worked for two years to decipher what the chemistry of the fossil was telling them about the color of the archaeopteryx’s feathers, mostly by studying feathers of modern birds.

“We had to start looking at live animals to see what the different elements we saw in the fossil might mean,” he said. “It was like learning a whole new language.”

Last year, researchers at Brown University published a study that said the archaeopteryx’s feather was black. They came to this conclusion after using a scanning electron microscope on the feather fossil that revealed melanosomes -- the pigment-producing parts of a cell -- that produced a black color.

“It’s actually quite a beautiful paper, but they took just tiny samples of the feather, not the whole thing,” Uwe Bergmann of the SLAC National Accelerator Laboratory at Stanford University said in a statement.

For this study, Manning said, his team was able to scan the entire feather.

In an interview with the Los Angeles Times, Manning said the techniques he used to determine the color of the archaeopteryx’s feather could be used to tell us other things from dinosaur fossils as well.

“We’ve only just begun this journey,” he said. “It’s like a whole new field of science.”

I asked whether fossils might be able to tell us something about the color of dinosaur skin.

“Ask me that question in a few more months,” he said. “That’s all I can say for now.”