Science & Research

Grad unveils dinosaur wings

By
Senior Staff Writer
Friday, February 3, 2012

As an undergraduate at the University of California at Berkeley, Ryan Carney, a PhD candidate, was the lead singer and songwriter for his  own punk rock band, said Kevin Padian, Carney’s undergraduate thesis advisor and professor of integrative biology at Berkeley. As a Brown graduate student, Carney has not left his rock days behind. Now he applies his creativity to a different kind of rock — the rock that contains fossils of the archaeopteryx, a 150-million-year-old winged dinosaur that has fascinated Carney ever since he watched a TV program about it as a young boy.

This year, Carney joined the ranks of scientists responsible for demystifying the animal when he discovered that the dinosaur’s wing feathers were black in color and contained structures identical to those of birds. His work was published in the January issue of the journal Nature Communications.

Though he studied integrative biology and studio art as an undergraduate, Carney did not pursue paleontology immediately out of college. Instead, he received two master’s degrees at Yale — one in business and one in public health — while doing research on the side. Carney said it was there that his friend Jakob Vinther, who would eventually become the study’s second author, found that squid fossils from deposits in Germany contained melanin, the pigment responsible for the coloring of most organisms.

The discovery that melanin is fossilized “opened up this whole new scientific method for reconstructing the color of ancient organisms,” Carney said. He decided to apply that method to the fossils of the creature in which he had never lost interest — the archaeopteryx.

In 2010, right before Carney arrived at the University, he contacted National Geographic and traveled to Germany to examine two archaeopteryx fossils unearthed in the mid-19th century — one fossil of the entire animal known as the Berlin specimen and one of just a single feather. While there, Carney tried two different scans, hoping to see fossilized melanosomes, organelles containing melanin. But the scanners weren’t powerful enough.

The third time proved the charm. Carney returned to Germany, this time equipped with a powerful field emission gun. And this time, his team was able to see the fine details of melanosome structure.

Carney said the scan allowed his team to compare the melanosomes in the feather to those of modern birds, the last living members of the dinosaur family. “They were identical in morphology, shape, the alignment, the angles,” he said. “Even down to the microscopic level, completely identical.”

Carney’s use of technology is “very exciting,” Padian said. “As technology gets better, we’re able to return to the same hunting grounds to ask questions with more sophistications.”

The melanosome’s presence also indicates with 95 percent certainty that the feathers were black. The chemical structure of the black color indicates an increase of the strength, mobility and thickness of the feather, all of which would have helped the feather to resist fracture while the animal’s wing was flapping through the air, Carney said.

Still, the presence of these melanosomes does not mean the archaeopteryx flew, Carney said, adding that this finding has been misinterpreted in the media.

“This isn’t proof that the archaeopteryx flew,” he said. “It’s proof that its feathers were strengthened, but you can’t say that it therefore was a flyer.”

Likewise, it is still unclear whether the archaeopteryx should be considered the first bird. “It’s been very hotly debated within the past year,” Carney said. “As more and more gaps in the fossil record are found, the distinction becomes blurred.” Different studies have placed the archaeopteryx on different sides of the divide between birds and other dinosaurs.

Though some articles have called the archaeopteryx the “missing link” between dinosaurs and modern birds, both Carney and Padian said this is a misnomer. “Things in fossil records are never exact intermediates,” Padian said. Though the archaeopteryx has many intermediate structural features and may be close to the direct ancestor of birds, “we would never say it’s a direct ancestor,” he added.

To celebrate both his finding and the 150th anniversary of the naming of the archaeopteryx, Carney had an image of the feather fossil tattooed on his arm, magnified by a scale of pi. “The actual feather is fairly small (around seven centimeters),” Carney wrote in an email to The Herald. “I wanted the tattoo to be roughly the same size as my old band’s guitar tattoo on my other arm to balance it out,” he wrote. “The proportion ended up being about three times so I used the more mathematically meaningful pi for the ratio.”  

Carney scouted out different locales before settling on whom to entrust with his feather tattoo. He decided on Black Lotus on Wickenden Street when, after bringing in a picture of the feather, tattoo artist Mike immediately identified it as belonging to the archaeopteryx.

Carney said the feather may not be his final tattoo — he has potential plans to get one of the full archaeopteryx.