The first fossilized signs of sequential molting support the idea that Microraptor was a flier
Such “sequential molting,” they say, suggests that Microraptor was an adept and frequent flier.Unlike many aquatic birds, modern songbirds lose only a few feathers at a time, enabling them to stay aloft year-round for foraging or to escape predators. Microraptor’s shorter feathers appear in just a small patch on one of the dinosaur’s four wings — suggesting that the dinosaur molted sequentially, too, bird ecologist Yosef Kiat at the University of Haifa in Israel and colleagues report.
All modern, adult birds molt at least once a year to replace old, damaged feathers, or to exchange their bright summer colors for drab winter camouflage. Genetic reconstructions of bird lineages have previously suggested that sequential molting has existed in birds for at least 70 million years, and was a trait of the common ancestor of all modern birds. But this is the first fossil evidence of a nonbird dinosaur exhibiting this behavior. Furthermore, the researchers say, the find would push back the estimated origins of sequential molting by 50 million years or so.
