For starters, the bird had small feathers on its hind legs. When he began doing a feather-by-feather reconstruction of its wings, working from a fossil in Germany, he found it didn’t look like a modern bird at all. Instead of the single layer of feathers that give modern birds their dextrous flight abilities, the fossil appeared to have layers of feathers stacked on top of each other, almost like two-ply tissues.
“I realized you couldn’t really get from what the fossils showed to the way people were drawing it,” Longrich said. “People have been drawing the wing this one way for more than 100 years, and had this particular idea about what the wing would look like. And this is coming along after more than a century and saying we got it wrong.”
His painstaking study of the Archaeopteryx fossil suggested to Longrich that this Jurassic-era bird had a primitive wing, and may not have been very good at flying. But instead of publishing his observation, he decided to sit on it. He wasn’t sure that his colleagues would be convinced; it might have been something strange about the way the specimen he was studying was fossilized.
A few years later, a scientist working down the hall from him, Jakob Vinther, began studying a fossil of a feathered dinosaur that had been recently discovered in China, called Anchiornis huxleyi. Vinther was not a bird specialist—in fact, Longrich said, Vinther normally studied fossils of ancient squid, octopi, and worms. But that also meant Vinther didn’t have the same preconceptions, and when he looked at the fossil he also saw wings with multiple layers of feathers.