Archaeopteryx’s newly discovered black wing ideal for flight

An international team of researchers, including Dr. Matthew Shawkey, University of Akron associate professor of biology, and Dr. Liliana D'Alba, UA postdoctoral fellow, has discovered that the fossilized feather of the Archaeopteryx — arguably the most famous fossil species in the world — was black. The researchers' finding indicates that the iconic "first bird" was well suited for flying.

Until now, the type of feather and its location on the prehistoric bird, dating from the Jurassic period, were unknown. However, the feather's newly discovered black color reveals it was a wing feather, and was likely rigid against wear and ideal for flight. Nature Communications presents findings by the team, led by Brown University biologist Ryan Carney, Jan. 24, 2012, in New evidence on the colour and nature of the isolated Archaeopteryx feather.

Shedding light on ancient mystery

 "Feather color tells us a lot about birds’ communication, protection mechanisms and mechanical attributes," Shawkey says. "Before our previous research, we didn’t have any idea of the colors of primitive birds or dinosaurs."

Shawkey refers to his and D'Alba's earlier role in determining the predominantly reddish-brown color of the extinct, 155-million-year-old feathered dinosaur Anchiornis huxleyi, in 2010. Shortly afterward, the two researchers and their colleagues revealed that the 36-million-year-old giant penguin, Inkayacu paracasensis, was reddish brown and gray.

In all three studies, researchers statistically compared the shape and size of melanosomes, the pigment-containing sacs in feathers of living birds, with melanosomes in the fossil feathers, to reconstruct their colors. The melanosomes' shapes indicate color. For instance, a rod-shaped melanosome typically denotes black and a spherical shape, brown.

Shawkey and D'Alba compared the Archaeopteryx's melanosomes with some 115 samples, nearly doubling the amount of samples performed for the first two studies and broadening the depth of their sampling to include a variety of birds, from common singing birds (used for the previous two studies) to primitive birds such as ostriches, birds of prey and seabirds.

"The increased diversity improves confidence in our finding," Shawkey says. "We show, with 95 percent certainty, that the feather was a black wing feather with denser distribution of black melanin at the tips."

D'Alba adds that because maximum turbulence occurs at a bird's wing tips during flight, the increased density of melanin at the feather tips protected the Archaeopteryx's feathers against damage during flight.

Media contact: Denise Henry, 330-972-6477 or henryd@uakron.edu.